WO2022034294A1

WO2022034294A1 - Foam stabilisation

Info

Publication number: WO2022034294A1
Application number: PCT/GB2021/052031
Authority: WO
Inventors: James Jennings; Anthony J. Ryan; Steven P. Armes
Original assignee: The University Of Sheffield
Priority date: 2020-08-14
Filing date: 2021-08-05
Publication date: 2022-02-17
Also published as: GB202012750D0

Abstract

The present invention relates to the use of copolymer surfactants in foam stabilisation. Copolymers, especially random or statistical copolymers, containing a statistical ensemble both solvophilic and solvophobic monomers perform particularly well in foam stabilisation applications, especially in the context of hand-sanitising foams, firefighting foams, and polymeric foams, such as polyurethane foams.

Description

FOAM STABILISATION

INTRODUCTION

[0001] The present invention relates to copolymer surfactants, compositions containing the same, and the use of such surfactants in foam stabilisation. In particular, the invention relates to the use of such copolymer surfactants in the context of hand-sanitising foams, firefighting foams, and polyurethane foams.

BACKGROUND

[0002] The stabilisation of foams in non-aqueous liquids (i.e. organic solvents) enables a diverse range of applications from hand sanitisers to firefighting, but preparation of these foams poses significant physicochemical challenges. One major requirement for the stabilisation of foams is that the surfactant must impart a surface tension gradient between air and the liquid to be foamed (i.e. Y_{surfactant-air} < Y_liquid-air). Foam stabilisation in water-rich mixtures is relatively easy to achieve using conventional small molecule and polymeric surfactants, owing to the relatively high water-air surface tension (Y_water-air = 72.8 mNm^-1 at 20 °C). However, the majority of organic solvents have Y_liquid-air in the region of 20-35 mNm^-1. Stabilising foams within these liquids necessitates a surfactant with extremely low surface energy, beyond the range accessible to most conventional organic surfactants. Conventionally, silicone and fluorine-containing surfactants are effective at foaming organic liquids, and are widely used in the aforementioned foam-based applications.

[0003] FIG. 1 shows surface tension values for ethanol/water mixtures, plotted alongside typical values for typical small molecule surfactants with different chemistries, taken from the literature (“Micellar Structure of Silicone Surfactants in Water from Surface Activity, SANS and Viscosity Studies”, Soni et al, J. Phys. Chem. B 2002, 106, 2606-2617; “Fluoro- vs hydrocarbon surfactants: Why do they differ in wetting performance?”, Kovalchuk etal, Adv. Colloid Interface Sci. 2014, 210, 65-71 ; “Physico-chemical properties of siloxane surfactants in water and their surface energy characteristics”, Srividhya et al, Polymer 2007, 48, 1261 -1268). The black box encompasses the mixtures typically adopted for hand sanitisation applications.

[0004] In the field of hand sanitisation, high alcohol formulations are commonplace, and may exist in the form of liquids, gels, or foams. There is evidence to suggest that foams provide superior efficacy in two ways. Firstly, the foam structure helps provide optimal dosage and retention on the hands, where liquid or gels may spill through the fingers. Secondly, the experience of using a foam is considered by many to be more pleasant, owing to the creamy skin feel. Typical hand sanitiser formulations contain 50-90% alcohol by weight (ethanol and/or isopropyl alcohol), with the remainder consisting of water. The low Y_liquid-air values of these high-alcohol mixtures (FIG. 1) makes foam formation difficult, and therefore unconventional surfactants must be employed to achieve foaming. To date, hand sanitiser foaming surfactants have typically been silicone- based. However, evidence of potentially harmful effects of silicone-based materials within the environment have emerged, thereby providing a need for silicone-free surfactants. Furthermore, when current surfactants remain deposited on the skin after alcohol evaporation they have been found to leave an unpleasant greasy layer. As such, a surfactant providing a more pleasant experience, for instance by depositing a moisturising layer onto the hands, would help to increase compliance in healthcare workers and the like.

[0005] In the context of firefighting, foams offer a favourable method of extinguishing flammable liquid (i.e. fuel) fires. A firefighting foam acts as a low density medium that spreads water across the surface of the fuel, cooling and smothering the fire by starving the underlying fuel of oxygen. Amongst the key properties of an effective firefighting foam are stability in the presence of the flammable liquid (e g., alkanes, alcohols), and the ability to solidify or precipitate to form a film on top of the liquid. Although typical firefighting foams are dispensed from predominantly aqueous solutions, they must be stable when mixed with organic liquids, and thus the physicochemical requirements are somewhat closely related to high alcohol sanitising foams (i.e, Y_{surfactant-air} < Y_liquid-air)- Currently, the most common foam-stabilising agents used in firefighting are small molecule fluorosurfactants. However, there are negative health effects associated with exposure to fluorosurfactants, and their ability to accumulate in the environment poses further problems. [0006] The foam-stabilisation properties required for the aforesaid applications are also applicable to the stabilisation of foam expansion during polyurethane (PU) synthesis. The prepolymer formula for PU foam synthesis is a complex mixture of organic liquids (principally polyisocyanates and polyols) with a small fraction of water as the blowing agent. Therefore, a successful PU foam surfactant must be surface active in liquids with low y^ua-air- Surfactants for PU foams are most commonly fluorinated or silicone-based materials, both of which are undesirable for both environmental and health reasons. Furthermore, silicone-based polymers can be highly mobile within polymer foams and thus may leach out, leading to loss of product quality over time.

[0007] It is an object of the invention to address one or more of the aforesaid problems or to address one of more other problems inherent in the prior art.

[0008] An object of the invention is to develop and/or deploy a class of surfactants that can exhibit comparable or improved performance to those currently in use, especially in the context of the aforesaid applications. Preferably this class of surfactants would exhibit fewer adverse properties than those currently in use. For instance, this class of surfactants may exhibit fewer adverse health impacts and/or fewer adverse environmental impacts.

SUMMARY OF THE INVENTION

[0009] According to an aspect of the present invention there is provided a copolymer compound, suitably as defined herein. The copolymer compound is preferably a statistical copolymer, preferably a substantially random copolymer.

[0010] According to a further aspect of the present invention there is provided a foamable composition, suitably as defined herein. The foamable composition preferably comprises the aforementioned copolymer compound. The foamable composition preferably comprises a polar solvent system. The foamable composition preferably comprises some water, though suitably less than 40 wt% water.

[0011] According to a further aspect of the present invention there is provided a foamable composition dispenser, comprising a reservoir, a dispensing nozzle, and a fluid connection (or conduit) between the reservoir and the dispensing nozzle.

[0012] According to a further aspect of the present invention there is provided a foamed composition, suitably as defined herein. The foamed composition may alternatively be termed “a foam”. The foamed composition preferably comprises the aforementioned copolymer compound. The foamed composition is suitably a foamed form of the aforementioned foamable composition, though suitably said foamed composition may additionally comprises a gas (e g. within the structure of the foam, e.g. within bubbles therein). The foam may be a wet foam or a (substantially) dry foam.

[0013] According to a further aspect of the present invention there is provided a foamable personal care composition, suitably as defined herein. Suitably, the aforementioned foamable composition is a foamable personal care composition. Suitably the foamable personal care composition is a hand-sanitizer.

[0014] According to a further aspect of the present invention there is provided a foamable hand-sanitizer, suitably as defined herein. Preferably, the foamable hand-sanitizer comprises at least 45%, preferably at least 50%, preferably at least 55%, more preferably at least 60%, and most preferably at least 65% sanitizing solvent. The sanitizing solvent is suitably an alcohol, suitably a (2-3C)alcohol, suitably ethanol or isopropanol, most suitably ethanol.

[0015] According to a further aspect of the present invention there is provided a hand-sanitizer dispenser, comprising a reservoir, a dispensing nozzle, and a fluid connection (or conduit) between the reservoir and the dispensing nozzle.

[0016] According to a further aspect of the present invention, there is provided a firefighting concentrate composition, suitably as defined herein. The firefighting concentrate suitably comprises a copolymer compound as defined herein, suitably instead of or in addition to one or more other surfactants. The firefighting concentration may suitably further comprise further firefighting composition ingredients. [0017] According to a further aspect of the present invention, there is provided a foamable firefighting composition. The foamable firefighting composition is suitably formed by mixing the aforesaid firefighting concentrate with a solvent system (suitably water). The aforementioned foamable composition may be a foamable firefighting composition.

[0018] According to a further aspect of the present invention, there is provided a foamed firefighting composition. The foamed firefighting composition is suitably formed by aspirating (whether by primary or secondary aspiration) the aforesaid foamable firefighting composition, suitably with a gas, for example, air.

[0019] According to a further aspect of the present invention there is provided a (foamed or foamable) firefighting composition dispenser (or a fire-extinguisher), comprising a reservoir, a dispensing nozzle, and a fluid connection (or conduit) between the reservoir and the dispensing nozzle. The reservoir may contain a foamed firefighting composition (i.e. pre-foamed) or a foamable firefighting composition (i.e. a composition that will be transformed into a foam). Fire- extinguishers or fire-hoses may dispense either “aspirated” (or primary aspirated) foam or “non-aspirated” (or secondary aspirated) foam, depending on the circumstances. The former means the dispenser contains a pre-foamed mix (i.e. foamed composition rather than foamable composition) whereas the latter means the dispenser contains an unfoamed but foamable composition.

[0020] According to a further aspect of the present invention there is provided a polymeric foam (or solid foam), suitably as defined herein. Suitably, the aforementioned foamable composition is a polymeric foam (or solid foam).

[0021] According to a further aspect of the present invention there is provided a foamable polymeric composition or foamable polymerizable composition (e g. comprising polymerizable monomer(s)), suitably as defined herein. Suitably, the aforementioned foamable composition is a foamable polymeric composition or foamable polymerizable composition. Suitably the foamable polymeric composition or foamable polymerizable composition may be used to form the aforementioned polymeric foam.

[0022] According to a further aspect of the present invention there is provided a polyurethane foam, suitably as defined herein. Suitably, the aforementioned foamable composition is a polyurethane foam.

[0023] According to a further aspect of the present invention there is provided a foamable polyurethane composition or polyurethane precursor composition (e g. comprising polymerizable monomers, for instance, (di)isocyanate monomer(s) and polyol monomer(s)), suitably as defined herein. Suitably, the aforementioned foamable composition is a foamable polyurethane composition or polyurethane precursor composition. Suitably the foamable polyurethane composition or polyurethane precursor composition may be used to form the aforementioned polyurethane foam.

[0024] According to a further aspect of the present invention there is provided a blowing agent composition, suitably for use in the production of polymeric foams, such as polyurethane foams.

[0025] According to a further aspect of the present invention there is provided a method of manufacturing a copolymer compound, suitably as defined herein.

[0026] According to a further aspect of the present invention there is provided a method of manufacturing a foamable composition, suitably as defined herein.

[0027] According to a further aspect of the present invention there is provided a method of manufacturing a foamed composition, suitably as defined herein.

[0028] According to a further aspect of the present invention there is provided a method of manufacturing a foamable personal care composition, a foamable firefighting composition, a polymeric foam (or solid foam), a foamable polymeric composition, foamable polymerizable composition, a polyurethane foam, a foamable polyurethane composition, or a polyurethane precursor composition, suitably as defined herein.

[0029] According to a further aspect of the present invention there is provided a method of generating a foam, suitably as defined herein. Such a method preferably comprises foaming the aforesaid foamable composition.

[0030] According to a further aspect of the present invention there is provided a method of stabilising a foam, suitably as defined herein. Such a method preferably comprises incorporating the aforementioned copolymer compound within the foam or precursor foamable composition. [0031] According to a further aspect of the present invention there is provided a use of a copolymer compound for stabilising a foam, suitably as defined herein. Preferably such a use comprises incorporating the aforementioned copolymer compound within the foam or precursor foamable composition.

[0032] Any features, including optional, suitable, and preferred features, described in relation to any particular aspect of the invention may also be features, including optional, suitable and preferred features, of any other aspect of the present invention unless incompatible therewith.

BRIEF DESCRIPTION OF THE DRA WINGS

[0033] For a better understanding of the invention, and to show how embodiments of the same are put into effect, reference is now made, by way of example, to the following diagrammatic drawings, in which:

[0034] FIG. 1 shows surface tension values for ethanol/water mixtures, plotted alongside minimal reported values for typical small molecule surfactants with different chemistries, taken from the literature. The black box encompasses the mixtures typically adopted for hand sanitisation applications.

[0035] FIG. 2 shows schematic representations of a wet and dry foam, with gas bubbles amongst a solvent system. The left image may be considered a substantially wet foam since the gas bubbles are separated by a reservoir of solvent. The right image corresponds to a dry foam where gas bubbles are closer together with less solvent in between. As a foam dries, gas bubbles may be susceptible to coalescence and bursting, which results in foam reduction. As such, it is desirable to stabilise these gas bubbles and mitigate coalescence, Ostwald ripening and bursting. As such, the invention seeks to stabilise such foams using particular copolymer surfactants.

[0036] FIG. 3 is a schematic representation of block-copolymer surfactant molecules arranged at the surface of a gas bubble. Here, the solvophobic portions of the block copolymer (and said block’s polymeric backbone) are oriented towards the gas bubble, whilst the solvophilic portions of the block copolymer (and its corresponding polymeric backbone) lie substantially within the solvent surrounding the gas bubble. In this manner the surfactant molecules inhibit coalescence, Ostwald ripening, and bursting of gas bubbles via steric and/or electrostatic interactions, and other mechanisms.

[0037] FIG. 4 is a schematic representation of a statistical, random, or alternating copolymer surfactant molecules arranged at the surface of a gas bubble. In contrast to the block copolymer surfactants illustrated in FIG. 3, the backbones of these statistical, random, or alternating copolymers effectively align at the gas bubble interface such that solvophobic moieties (of solvophobic monomers) are oriented towards the gas bubble and solvophilic moieties (of solvophilic monomers) lie substantially within the solvent surrounding the gas bubble. The surfactant molecules inhibit coalescence, Ostwald ripening, and bursting of gas bubbles via steric and/or electrostatic interactions, and other mechanisms. As such, the statistical, random, or alternating copolymer molecules may act as a surfactant by adsorbing to bubble interfaces, albeit they align differently to the aforesaid block copolymers.

[0038] FIG. 5 is a schematic representation of the multi-molecular micelles formed by block copolymers in solution and single-molecule micelle thought, by the inventors, to be formed by statistical, random, or alternating copolymer surfactant molecules in solution. For block copolymer surfactants to act as foam stabilisers, they must first dissociate from their micellar state, diffuse through solvent and thereafter collect at a gas bubble interface. This poses a kinetic barrier, and may also pose a thermodynamic barrier depending on the relative Gibbs Free Energy of the micelle solution vs stabilised foam. For statistical, random, or alternating copolymer surfactants to act as foam stabilisers, they must first unfold from their micellar state and thereafter collect at a gas bubble interface. Though this poses a kinetic barrier, it is not as onerous as that for multimolecular micelles, as per block copolymers. It is difficult to assess thermodynamic barriers, since solvent-based entropic factors are difficult to model.

[0039] FIG. 6 is an array of overlapping GPC traces (Rl detector) from 6 different TMHA-stat-PEGA copolymers synthesised from the high throughput study as described in Table 4.

[0040] FIG. 7 is a graph showing water loss against time from a study of PES membranes coated with either the incumbent PDMS-PEO block copolymer surfactants (open squares) or TMHA-stat-PEGA (closed triangles). [0041] FIG. 8 shows snapshots from videos taken during PU foaming in the presence of TMHA-PEGA surfactant (top row), a conventional TEGOstab silicone-based surfactant (middle row), and without surfactant (bottom row). Image columns are labelled with time elapsed after adding the pre-polymer mixture to the empty vessel.

[0042] FIG. 9 shows various stages of foaming for a MAA-HFBMA copolymer solution (1.5 wt%) in 2:1 waterethanol (by volume) using an air stone pump: (A) the air stone is lowered into solution within a measuring cylinder; (B) after foaming for 5 s, after which the foam filled the volume of the measuring cylinder; (C) 5 min after foaming, where ca. 65% foam volume remained; (D) after applying the foam to a petri dish filled with heptane; (E) 3 min after applying the foam to heptane; (F) demonstration of the solid film forming properties of PMAA-PHFBMA upon drying on a de Nuoy ring 2 min after a ring tensiometry experiment (highlighted by white arrow).

[0043] FIG. 10 shows (A) Example of bubble pressure tensiometry data for 50% ethanol (solid line) and in the presence of multiple concentrations of surfactant C (increasing concentration with greyscale). (B) Concentration dependence of surface tension measured at a surface age of 1 s for copolymers C-F in 60% ethanol. Data from (B) was used to calculate diffusion constants using Equation 3, which are plotted for A-F as a function of concentration in (C). (D) Table describing characteristics of copolymer surfactants A-F, where y_min values were recorded at 50% ethanol for A & B, 60% ethanol for C- F.

[0044] FIG. 11 shows (A) stacked SAXS plots (subtracted) for a number of statistical copolymer surfactants in an ethanol/water mixture (2/1 by mass). (B) The copolymer compositions are listed in order (top to bottom) in the table, alongside the measured scattering minima and radius of dispersed nanoparticles. The very small radii of the micelles is indicative of single molecule micelles or micelles with very low aggregation numbers. (C) A schematic diagram showing the proposed mechanism by which copolymer surfactants change conformation at the interface to stabilise foam formation.

[0045] FIG. 12 shows: A) variation of interfacial tension at the solvent-air interface with different ethanol-water mixtures (ethanol mass fractions provided) containing fixed concentrations (5 g/dm³) of each of TMHA-stat-PEGA and PTMHA-block-PPEGA copolymers; B) variation of interfacial tension at the solvent-air interface with different concentrations (0.1-5 g/dm³) of TMHA-stat-PEGA and PTMHA-block-PPEGA copolymers present at different concentrations in ethanol/water (61.2% w/w ethanol); and C) variation of interfacial tension at the solvent-air interface (Y_solvent/air) with different ethanol-water mixtures (ethanol mass fractions provided) containing a fixed concentration (5 g/dm³) of TMHMA-stat-PEGMA, a methacrylic analogue of TMHA-stat-PEGA that has a significantly higher glass transition temperature (7g). In each figure, blue triangles represent statistical copolymer, orange squares represent block copolymer, and the dotted line represents the solvent system without any copolymers present.

DETAILED DESCRIPTION OF THE INVENTION

DEFINITIONS

[0046] Unless otherwise stated, the following terms used in the specification and claims have the following meanings set out below.

[0047] Throughout the description and claims of this specification, the words “comprise” and “contain” and variations of them mean “including but not limited to”, and they are not intended to (and do not) exclude other moieties, additives, components, integers or steps. Throughout the description and claims of this specification, the singular encompasses the plural unless the context otherwise requires. In particular, where the indefinite article is used, the specification is to be understood as contemplating plurality as well as singularity, unless the context requires otherwise.

[0048] Preferably, unless stated otherwise, where reference is made to a parameter (e g. pH, pKa, etc.) or state of a material (e g. liquid, gas, etc.) which may depend on pressure and/or temperature, preferably in the absence of further clarification such a reference refers to said parameter at standard ambient temperature and pressure (SATP). SATP is a temperature of 298.15 K (25 °C, 77 °F) and an absolute pressure of 100 kPa (14.504 psi, 0.987 atm). [0049] According to the Pharmacopeia of the United States of America (USP), the following descriptive terms are used to describe varying degrees of solubilities (measured as parts by mass of solvent required to dissolve 1 part by mass of solute) of a given solute in a given solvent:

[0050] Solubility and molecular lipophilicity may also be defined by reference to “log P” values, which may be experimentally determined our calculated by ways well known in the art. “Calculation of molecular lipophilicity: State-of-the- art and comparison of log P methods on more than 96,000 compounds”, Mannhold et al, J. Pharm. Sci. 2009, 98, 861 -893, provides further details.

[0051] Terms such as “HLB” or “HLB values” are well understood in the art, and referto the hydrophilic-lipophilic balance (HLB) of a surfactant. HLB values are on a scale of 0 to 20, and are calculable using Griffin’s method, where:

where M is the molecular mass of the entire molecule and M_h is the molecular mass of the hydrophilic portion thereof.

[0052] Unless stated otherwise, references herein to a “pKa” should be construed as a pKa value in water at standard ambient temperature and pressure (SATP), preferably of the conjugate acid of the relevant species.

[0053] Herein, amounts stipulated for components and ingredients, whether specified in terms of “parts”, ppm (parts per million), percentages (%, e g. wt%), or ratios, are intended to be by weight, unless stated otherwise.

[0054] The term "substantially free" when used in relation to a given component of a composition, refers to a composition to which essentially none of said component has been added. When a composition is “substantially free” of a given component, said composition preferably comprises no more than 0.1 wt% of said component, preferably no more than 0.01 wt% of said component, preferably no more than 0.001 wt% of said component, preferably no more than 0.0001 wt% of said component, preferably no more than 0.00001 wt%, preferably no more than 0.000001 wt%, preferably no more than 0.0000001 wt% thereof, most preferably no more than 0.0001 parts per billion (by weight).

[0055] The term "entirely free" when used in relation to a given component of a composition, refers to a composition containing none of said component.

[0056] Where the quantity or concentration of a particular component of a given composition is specified as a weight percentage (wt% or %w/w), said weight percentage refers to the percentage of said component by weight relative to the total weight of the composition as a whole. It will be understood by those skilled in the art that the sum of weight percentages of all components of a composition (whether or not specified) will total 100 wt%. However, where not all components are listed (e g. where compositions are said to “comprise” one or more particular components), the weight percentage balance may optionally be made up to 100 wt% by unspecified ingredients (e g. a diluent, such as water, or other non-essentially but suitable additives).

[0057] Where a composition is said to comprise a plurality of stipulated ingredients (optionally in stipulated amounts of concentrations), said composition may optionally include additional ingredients other than those stipulated. However, in certain embodiments, a composition said to comprise a plurality of stipulated ingredients may in fact consist essentially of or consist of all the stipulated ingredients, optionally in the amounts specified. In either circumstance, an individual component may itself comprise, consist essentially of, or consist of a sub-component or one or more sub-components. Herein, wherever the term “comprise” is used it may, where compatible with the context, be replaced by “consists essentially of” or “consists of".

[0058] Herein, where a composition is said to “consists essentially of’ a particular component, said composition preferably comprises at least 70 wt% of said component, preferably at least 90 wt% thereof, preferably at least 95 wt% thereof, most preferably at least 99 wt% thereof. Preferably, a composition said to “consist essentially of” a particular component consists of said component save for one or more trace impurities.

[0059] Herein, unless stated otherwise, all chemical nomenclature may be defined in accordance with IUPAC definitions.

[0060] Herein, the term “hydrocarbon” is well understood in the art, and refers to compounds containing carbon and hydrogen only. The term “hydrocarbyl” general refers any aliphatic, acyclic, or cyclic (including aryl) hydrocarbon group, suitably with no heteroatoms. Such compounds include, inter alia, alkanes, alkenes, alkynes, arenes, and cyclic versions thereof. The term “hydrocarbon” anthracene, naphthalene, benzene, and/or derivatives thereof (e g. toluene).

[0061] Herein, the term "carbocyclyl", “carbocycle” or "carbocyclic" refers to a radical of a non-aromatic cyclic hydrocarbon group, generally having from 3 to 10 ring carbon atoms (i.e. (3-10C)carbocyclyl) and zero heteroatoms in the non-aromatic ring system. Suitably, carbocyclyl groups include (3-nC)cycloalkyl and (3-nC)cycloalkenyl. Exemplary embodiments include: cyclobutyl, cyclobutenyl, cyclopentyl, cyclopentenyl, cyclohexyl, cyclohexenyl, cyclohexadienyl, cycloheptyl, cycloheptenyl, cycloheptadienyl, cycloheptatrienyl, cyclooctyl, cyclooctenyl, bicyclo[2.2.1]heptanyl, bicyclo[2.2.2]octanyl, and the like.

[0062] In this specification the term “alkyl” includes both straight and branched chain alkyl groups. References to individual alkyl groups such as “propyl” are specific for the straight chain version only and references to individual branched chain alkyl groups such as “isopropyl” are specific for the branched chain version only. For example, “(1 -6C)alkyl” includes (1 -4C)alkyl, (1 -3C)alkyl, propyl, isopropyl and t-butyl. A similar convention applies to other radicals, for example “phenyl(1- 6C)alkyl” includes phenyl(1 -4C)alkyl, benzyl, 1 -phenylethyl and 2-phenylethyl.

[0063] The term "(m-nC)" or "(m-nC) group" used alone or as a prefix, refers to any group having m to n carbon atoms.

[0064] An “alkylene,” “alkenylene,” or “alkynylene” group is an alkyl, alkenyl, or alkynyl group that is positioned between and serves to connect two other chemical groups. Thus, “(1 -6C)alkylene” means a linear saturated divalent hydrocarbon radical of one to six carbon atoms or a branched saturated divalent hydrocarbon radical of three to six carbon atoms, for example, methylene, ethylene, propylene, 2-methylpropylene, pentylene, and the like.

[0065] “(2-6C)alkenylene” means a linear divalent hydrocarbon radical of two to six carbon atoms or a branched divalent hydrocarbon radical of three to six carbon atoms, containing at least one double bond, for example, as in ethenylene, 2,4- pentadienylene, and the like.

[0066] “(2-6C)alkynylene” means a linear divalent hydrocarbon radical of two to six carbon atoms or a branched divalent hydrocarbon radical of three to six carbon atoms, containing at least one triple bond, for example, as in ethynylene, propynylene, and butynylene and the like.

[0067] “(3-8C)cycloalkyl” means a hydrocarbon ring containing from 3 to 8 carbon atoms, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl or bicyclo[2.2.1 ]heptyl.

[0068] “(3-8C)cycloalkenyl” means a hydrocarbon ring containing at least one double bond, for example, cyclobutenyl, cyclopentenyl, cyclohexenyl or cycloheptenyl, such as 3-cyclohexen-1-yl, or cyclooctenyl.

[0069] “(3-8C)cycloalkyl-(1-6C)alkylene” means a (3-8C)cycloalkyl group covalently attached to a (1 -6C)alkylene group, both of which are defined herein.

[0070] The term “halo” refers to fluoro, chloro, bromo and iodo.

[0071] “Heteroaryl(1 -6C)alkyl” means a heteroaryl group covalently attached to a (1-6C)alkylene group, both of which are defined herein. Examples of heteroaralkyl groups include pyridin-3-ylmethyl, 3-(benzofuran-2-yl)propyl, and the like. [0072] The term “aryl” means a cyclic or polycyclic aromatic ring having from 5 to 12 carbon atoms. The term aryl includes both monovalent species and divalent species. Examples of aryl groups include, but are not limited to, phenyl, biphenyl, naphthyl and the like. In particular embodiment, an aryl is phenyl.

[0073] The term “aryl(1-6C)alkyl” means an aryl group covalently attached to a (1-6C)alkylene group, both of which are defined herein. Examples of aryl-(1-6C)alkyl groups include benzyl, phenylethyl, and the like

[0074] This specification also makes use of several composite terms to describe groups comprising more than one functionality. Such terms will be understood by a person skilled in the art. For example heterocyclyl(m-nC)alkyl comprises (m-nC)alkyl substituted by heterocyclyl.

[0075] Wherever groups with large carbon chains are disclosed (e g. (1 -12C)alkyl, (1-8C)alkenyl, etc ), such groups may optionally be shortened, for instance containing a between 1 and 5 carbons (e g. (1 -5C)alkyl or (1-5C)alkenyl), or contain between 1 and 3 carbons (e.g. (1 -3C)alkyl or (1-3C)alkenyl instead of (1 -12C)alkyl or (1-8C)alkenyl).

[0076] The term "optionally substituted" refers to either groups, structures, or molecules that are substituted and those that are not substituted.

[0077] Where optional substituents are chosen from “one or more” groups it is to be understood that this definition includes all substituents being chosen from one of the specified groups or the substituents being chosen from two or more of the specified groups.

GENERAL POINTS AND ADVANTAGES REGARDING THE INVENTION

[0078] The present invention deploys a new class of copolymeric surfactants in the stabilisation of foams, especially foams that are formed from or exist within or in contact with a semi-organic medium (e g. alcoholic hand-sanitizers, firefighting foams, and polyurethane foams). Such surfactants are generally less harmful to health and/or the environment than those currently in use, especially foaming surfactants used with semi-organic media (e g. alcoholic hand-sanitizers, firefighting foams, and polyurethane foams for lightweight materials).

[0079] Statistical (especially random) or alternating copolymers, formed from a mixture of solvophilic and solvophobic monomers, have been found to be surprisingly excellent foam stabilising surfactants. Such a finding is completely unexpected, especially in the context of semi-organic media, in light of the prior art. Such statistical (especially random) or alternating copolymers have also proved surprisingly more efficacious in foam stabilisation than block copolymers.

[0080] The present invention is an advantageous by-product of problems experienced when trying to synthesise and purify the relevant copolymers in an ethanolic media, wherein excess foaming was found to occur. Such foaming proved to be a significant obstacle to the task in hand, but was seen as an opportunity by the present inventors. As such, the present invention is the consequence of a problematic experience repurposed for advantageous deployment in an entirely different context.

[0081] These surfactants can impart ultra-low surface energy at the solvent-air interface, and thereby effectively stabilise bubbles that constitute the foam. SAXS analysis reveals that these surfactants can fold into single molecule micelles within the solvent system, and the mechanism by which the inventive surfactants operate is thought to mirror the action of foamstabilising proteins adopted by nature to create ultra-stable aqueous foam nests, which protect eggs from harsh environmental conditions.

COPOLYMER COMPOUND

[0082] According to an aspect of the present invention there is provided a copolymer compound, suitably as defined herein. The copolymer compound is alternatively referred to herein as a “copolymer surfactant”. The copolymer compound is suitably a synthetic compound - i.e. not a natural product or a product isolated from nature. The copolymer compound suitably comprises, consists of, or is formed from (polymerisation of) a mixture of solvophobic monomer(s) and solvophilic monomer(s). [0083] The copolymer compound is preferably a non-block copolymer - i.e. a copolymer that is not specifically organised into distinct blocks. The copolymer compound is preferably selected from the group consisting of a statistical copolymer (most preferably a random or substantially random copolymer), a gradient copolymer (i.e. where average monomer composition changes gradually along the copolymer chain), an alternating copolymer, and a periodic copolymer. More preferably the copolymer compound is a statistical copolymer. Most preferably the copolymer is a (substantially) random copolymer. A random copolymer is considered a subset of statistical copolymers.

[0084] The polymeric backbone (backbone chain) of the copolymer compound may be any suitable polymeric backbone. The polymeric backbone may be a mixed backbone or a homogeneous backbone. Suitably the advantages of the invention stem from the moieties (e g. pendent groups) present in the respective monomers rather than any given backbone. Suitably the polymeric backbone has sufficient conformational freedom to orientate solvophobic (typically hydrophobic) groups away from solvophilic (typically hydrophilic) groups to thereby furnish sufficient amphiphilicity for surfactant behaviour.

[0085] Preferably, the copolymer compound has an HLB value between 3 and 17, preferably between 4 and 16, preferably between 5 and 15, more preferably between 6 and 14, most preferably between 6.5 and 13.5.

[0086] In an embodiment, the copolymer compound is free of fluorine atoms. In an embodiment, the copolymer compound is free of silicon atoms. In an embodiment, the copolymer compound is free of fluorine atoms and silicon atoms.

[0087] In an embodiment, the copolymer compound is free of fluorine-containing moieties. In an embodiment, the copolymer compound is free of silicon-containing moieties (e g. siloxane moieties). In an embodiment, the copolymer compound is free of fluorine-containing moieties and silicon-containing moieties.

[0088] If the copolymer compound comprises any fluorine atoms, those fluorine atoms are suitably part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide.

[0089] If the copolymer compound comprises any silicon atoms, those silicon atoms are suitably part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide.

[0090] The copolymer compound comprises (or is formed from) two or more different monomers (or monomeric units), optionally termed Mi, M₂, and M_n, most preferably two different monomers, optionally termed and M₂.

[0091] In an embodiment, suitably embodiments wherein the copolymer compound is a statistical copolymer, the copolymer compound is defined by Formula I: poly(M₁-co-M₂-co-M_n) wherein is a first monomer, M₂ is a second monomer, and M_n is an nth monomer (where said polymer comprises three or more monomers; if not M_n may be absent).

[0092] Herein, the copolymer compound of Formula I may be represented more simply as Formula la: poly(M₁-co-M₂) wherein, unless stated otherwise, said copolymer implicitly includes the option for an nth monomer as per Formula I. However, the copolymer compound of Formula la may comprise at most two monomers, and M₂ (i.e. is free of or substantially free of an nth monomer).

[0093] In an embodiment, the copolymer compound of Formula I is a statistical copolymer further sub-defined by Formula II: poly(M1-stat-M₂-stat-M_n) wherein is a first monomer, M₂ is a second monomer, and M_n is an nth monomer (where said polymer comprises three or more monomers).

[0094] In an embodiment, the copolymer compound of Formula la is a statistical copolymer further sub-defined by Formula Ila: poly(M₁-stat-M₂). [0095] In an embodiment, the copolymer compound of Formula II is a random statistical copolymer (or random copolymer) further sub-defined by Formula III: poly(M₁-ran-M₂-ran-M_n) wherein M₁ is a first monomer, M₂ is a second monomer, and M_n is an nth monomer (where said polymer comprises three or more monomers).

[0096] In an embodiment, the copolymer compound of Formula Ila is a random copolymer further sub-defined by Formula Illa: poly(M₁-ran-M₂).

[0097] As per the copolymer compounds of Formula la, unless stated otherwise, the copolymers of Formulae Ila and Illa implicitly includes the option for an nth monomer. However, such copolymer compounds may comprise at most two monomers, M₁ and M₂ (i.e. is free of or substantially free of an nth monomer). Unless the context dictates otherwise, the same applies to any later representations of the same or similar such formulae.

[0098] In a particular embodiment, the copolymer compound is an alternating copolymer (and any embodiments defined herein in relation to statistical or random copolymers may be applied to alternating copolymers), which may be represented by the formula: poly(M₁-a/f-M₂).

[0099] In another embodiment, the copolymer compound is a gradient copolymer (and any embodiments defined herein in relation to statistical or random copolymers may be applied to alternating copolymers), which may be represented by the formula: poly(M₁-grad-M₂).

[00100] Preferably, the monomers M₁ and M₂ of the aforesaid copolymer compounds constitute at least 70% of the monomer units of the copolymer, more preferably at least 90%, most preferably (substantially) 100% of the monomer units of the copolymer (i.e. the copolymer consists of only monomers M₁ and M₂).

[00101] Preferably, the aqueous solubility of monomer M₁ (as a free unpolymerized monomer or as a monomeric unit within a polymer or copolymer) is different to monomer M₂. Preferably, monomer M₁ is a solvophobic monomer and M₂ is a solvophilic monomer - i.e. suitably M₁ is less soluble in a specified solvent system or solvent medium (e g. foaming medium) than M₂.

[00102] Preferably M₁ is substantially insoluble in the specified solvent system and M₂ is substantially soluble in the same specified solvent system.

[00103] Preferably M₁ (or the solvophobic monomer) is either slightly soluble, very slightly soluble, or practically insoluble in a specified solvent system (which is suitably pure water at SATP). Such solubility terms are used in accordance with the relevant USP definitions (see above). As such, preferably at least 100 parts by mass of a specified solvent system (e g. water) are required to dissolve 1 part by mass of M₁. More preferably, M₁ is either very slightly soluble or practically insoluble in a specified solvent system (suitably pure water at SATP). As such, preferably at least 1000 parts by mass of a specified solvent system (e.g. water) are required to dissolve 1 part by mass of M₁.

[00104] Preferably M₂ (or the solvophilic monomer) is either very soluble, freely soluble, or soluble in a specified solvent system (which is suitably pure water at SATP). As such, preferably at most 30 parts by mass of a specified solvent system (e g. water) are required to dissolve 1 part by mass of M₂. More preferably, M₂ is either very soluble or freely soluble in a specified solvent system (suitably pure water at SATP). As such, preferably at most 10 parts by mass of a specified solvent system (e.g. water) are required to dissolve 1 part by mass of M₂.

[00105] Preferably M₁ (or the solvophobic monomer) is substantially insoluble in a specified solvent system (which is suitably pure water at SATP). Such solubility may be defined in accordance with the logP value of the monomer. As such, M₁ preferably has a logP value of at least 1.5. More preferably, M₁ preferably has a logP value of at least 3.0. More preferably, M₁ preferably has a logP value of at least 4.0. [00106] Preferably M₂ (or the solvophilic monomer) is substantially soluble in a specified solvent system (which is suitably pure water at SATP). Such solubility may be defined in accordance with the logP value of the monomer. As such, M₂ preferably has a logP value of less than 1.5. More preferably, M₂ preferably has a logP value of less than 1 . Most preferably, M₂ preferably has a logP value of less than 0.

[00107] In an embodiment, M₁ has a logP value of at least 2.0 and M₂ has a logP value of less than 1 . In an embodiment, M₁ has a logP value of at least 3.0 and M₂ has a logP value of less than 1. In an embodiment, M₁ has a logP value of at least 3.0 and M₂ has a logP value of less than 0.5. In an embodiment, M₁ has a logP value of at least 4.0 and M₂ has a logP value of less than 0.

[00108] Where the copolymer compound includes additional monomer, such additional monomers may be grouped with either monomer M₁ or M₂ in terms of its solubility properties - e g. an additional monomer may be solvophobic or solvophilic.

[00109] The solvophobic monomer (M₁) suitably has the structure RT-QT-BT, wherein RT represents one or more (most preferably one) pendent solvophobic (typically hydrophobic) groups, QT represents the remainder of the monomer molecule except for BT which represents an unpolymerized backbone portion of the monomer. The solvophilic monomer (M₂) suitably has the structure R₂-Q₂-B₂, wherein R₂ represents one or more (preferably one) pendent solvophilic (typically hydrophilic) groups, Q₂ represents the remainder of the monomer molecule except for B₂ which represents an unpolymerized backbone portion of the monomer. Whilst RT and R₂ are preferably substantially different, BT and B₂ are preferably similar or identical. Where further monomers are present within the copolymer compound, such an additional monomer(s) (M_n) may have the structure R_n-Q_n-B_n, wherein R_n represents one or more (most preferably one) pendent solvophobic (typically hydrophobic) groups, Q_n represents the remainder of the monomer molecule except for B_n which represents an unpolymerized backbone portion of the monomer.

[00110] Suitably the copolymer compound has is defined by Formula IV:

wherein R_{1 :} QT, R₂, Q₂, R_n, and Q_n, are defined as per above, whereas BT’, B₂’, and B_n’, are reacted (polymerised) backbone portions corresponding with the aforementioned BT, B₂, and B_n, wherein R_{1 :} QT, BT’, BT, R₂, Q₂, B₂’, B₂, R_n, Q_n, B_n’, and B_n, correspond to monomers M_{1 :} M₂, and M_n respectively, where M_n is an nth monomer (where said polymer comprises three or more monomers; if not M_n may be absent).

[00111] In line with the above, the copolymer compound of Formula IV may be further sub-defined by Formula V:

which itself may be further sub-defined by Formula VI:

[00112] Also in line with the above definitions, the copolymer compound of Formulas IV, V, and VI may be further subdefined by Formulas IVa, Va, and Via:

Formula Va

Formula Via

[00113] Additional definitions for copolymer compounds for alternating and gradient copolymer compounds may be represented thus:

[00114] As per the copolymer compounds of Formula la, unless stated otherwise, the copolymers of Formulas Iva, Va, and Via implicitly include the option for an nth monomer. However, such copolymer compounds may comprise at most two monomers, M₁ and M₂ (i.e. is free of or substantially free of an nth monomer).

[00115] Suitably RT comprises a continuous carbon chain (i.e. uninterrupted by heteroatoms, or interrupted by at most one heteroatom, such as an optionally substituted nitrogen atom) comprising at least 3 carbon atoms wherein at most one of said carbon atoms is attached to a heteroatom other than fluorine or silicon. Suitably RT comprises a continuous carbon chain comprising at least 3 carbon atoms wherein no more than one of said carbon atoms is attached to an oxygen or nitrogen atom. Suitably RT comprises a continuous carbon chain (i.e. uninterrupted by heteroatoms) comprising at least 4 such carbons atom, suitably at least 5 such carbon atoms, suitably at least 6 such carbon atoms. RT may comprise one or more fluorine substituents, though most suitably RT is free of any fluorine substituents. RT may comprise one or more siloxane substituents, though most suitably RT is free of any siloxane substituents. RT suitably comprises one or more branched hydrocarbyl moieties. RT suitably comprises at least one methyl (CH₃) group. RT may suitably comprise two or more methyl (CH₃) groups. In an embodiment, RT comprises three or more methyl (CH₃) groups. Preferably RT is a nonpolar group, suitably less polar than R₂. Most preferably, RT comprises a continuous carbon chain comprising at least 3 carbon atoms and at least one methyl group (or perfluoromethyl group). Preferably, the carbon chain length of any of the aforementioned carbon chains comprises at most 30 carbons, most preferably at most 25 carbons.

[00116] Suitably R₂ is free of any continuous carbon chains as defined in relation to RT . Suitably, where R₂ comprises a continuous carbon chain comprising 3 or more carbon atoms, at least two of said carbon atoms are attached to a heteroatom other than fluorine or silicon, suitably attached to oxygen atom(s) and/or nitrogen atom(s). R₂ suitably comprises one or more polar groups. R₂ suitably comprises at least one hydroxyl group, at least one amine group, a plurality of ether groups, a plurality of ester groups, or a plurality of amide groups. R₂ suitably comprises at least one hydroxyl group or a plurality of ether groups. R₂ is suitably free of any fluorine substituents. R₂ is suitably free of any siloxane substituents. R₂ is suitably free of any branched hydrocarbyl moieties. R₂ preferably comprises no more than one methyl group. Most preferably, R₂ is free of methyl groups (optionally except for a single terminal methyl group such as may be the case for PEGA or PEGMA groups; or optionally except where said methyl group is attached to a heteroatom). Preferably R₂ is a polar group, preferably more polar than RT . Preferably, R₂ is either H or a group comprising one or more heteroatoms, and suitably R₂ is free of any methyl groups (or perfluoromethyl groups). Most preferably, R₂ is either H or a group that is free of any methyl groups (or perfluoromethyl groups), free of any continuous carbon chains comprising 3 or more carbon atoms, and comprises one or more heteroatoms (preferably one or more oxygen atoms). However, larger hydrophilic groups can be beneficial to foamability, so suitably R₂ is not merely H, but comprises one or more hetero atoms (e g. O or N, most suitably O), suitably two or more hetero atoms, suitably three or more hetero atoms. For this reason, polyethyleneoxide/PEG R₂ groups may be particularly beneficial. Where R₂ comprises a PEG moiety, preferably said PEG moiety contains 2-100 monomeric (ethylene glycol) units, more preferably 3-50 monomeric units, most preferably 5-25 monomeric units. [00117] Herein, wherever R₂ is said to be free of methyl or perfluoromethyl groups, where the context allows this may be with the optional exception of a methyl or perfluoromethyl group attached to a heteroatom; or with the optional exception of a terminal methyl or perfluoromethyl group, suitably attached to a heteroatom, such as may be the case for PEGA or PEGMA. Suitably this optional exception applies where there exists a single terminal methyl group attached to a heteroatom.

[00118] BT and B₂ of monomers M₁ and M₂ suitably copolymerise to respectively form B< and B₂’ groups which together form a polymeric backbone of the copolymer. The copolymer compound may comprise a heterogeneous backbone, but most preferably comprises a homogeneous backbone, since the former may lead to gradients within the copolymer and reduce randomness. As such, most suitably, BT and B₂ are identical. Suitably, BT and B₂ are backbone portions independently selected from suitably a group consisting of acrylic, alkylacrylic, vinyl, alkyl-substituted vinyl, aryl-substituted vinyl groups. Preferably, BT and B₂ are backbone portions independently selected from suitably group consisting of acrylic and alkylacrylic groups. Most suitably, both BT and B₂ are acrylic groups.

[00119] The copolymer compound may comprise (or BT and B₂ are selected so as to form BT and B₂’ groups which together provide) a polyvinyl backbone, a polystyrene backbone, a polyester backbone, a polyvinylester backbone, a polyvinylamide backbone, a polyalkylene (e g. polyethylene, polypropylene, or polyisobutylene) backbone, a polyanhydride backbone, a polydiester or polydicarboxylate backbone (e g. hydrolysed form of polyanhydride), a polyacrylic backbone, a polyalkylacrylic (e g. polymethacrylic) backbone, polyoxyalkylene (e g. polyoxyethylene or polyoxypropylene) backbone, or mixed (heterogeneous) backbone comprises a combination of two or more of the aforesaid (e g. mixed polyacrylic-polymethacrylic backbone, such that one of BT or B₂ is an acrylic group, and the other of BT or B₂ is a methacrylic group). Preferably, the copolymer compound has a homogeneous polyacrylic backbone or a homogeneous polyalkylacrylic backbone, most preferably a polyacrylic backbone (i.e. suitably BT and B₂ are both acrylic groups).

[00120] Suitably, M₁ is a monomer having the formula M_1A:

wherein R_BT is either H or a (1 -2C)alkyl (e g. methyl), XT is O or NH, and RT is a pendent solvophobic (typically hydrophobic) group, suitably as defined hereinbefore or hereinafter. Most preferably, R_BT is H or CH₃, most preferably H. Most preferably, XT is O. Preferably RT is a non-polar group. Most preferably, RT comprises a continuous carbon chain comprising at least 3 carbon atoms and at least one methyl group (or perfluoromethyl group).

[00121] Suitably, M₂ is a monomer having the formula M_a:

wherein R_B2 is either H or a (1 -2C)alkyl (e g. methyl), X₂ is O or NH, and R₂ is a pendent solvophilic (typically hydrophilic) group, suitably as defined hereinbefore or hereinafter. Most preferably, R_B2 is H or CH₃, most preferably H. Most preferably, X₂ is O. Preferably R₂ is a polar group, preferably more polar than RT. Preferably, R₂ is either H or a group comprising one or more heteroatoms, and suitably R₂ is free of any methyl groups (or perfluoromethyl groups), with the optional exception of a single terminal methyl group attached to a heteroatom. Most preferably, R₂ is either H or a group that is free of any methyl groups (or perfluoromethyl groups) , with the optional exception of a single terminal methyl group attached to a heteroatom, free of any continuous carbon chains comprising 3 or more carbon atoms, and comprises one or more heteroatoms (preferably one or more oxygen atoms).

[00122] Suitably, the copolymer compound comprises a monomer M_1A and monomer M_2A, wherein R_B1 and R_B2 are independently H or CH₃ (though preferably R_B1 and R_B2 are the same), X1 and X₂ are both O, RT comprises a continuous carbon chain comprising at least 3 carbon atoms and at least one methyl group (or perfluoromethyl group), and R₂ is either H or a group that is free of any methyl groups (or perfluoromethyl groups), with the optional exception of a single terminal methyl group attached to a heteroatom, free of any continuous carbon chains comprising 3 or more carbon atoms, and comprises one or more heteroatoms (preferably one or more oxygen atoms). [00123] Suitably, the copolymer compound comprises a monomer M_1A and monomer M_a, wherein R_BT and R_B2 are independently H or CH₃ (though preferably R_B1 and R_B2 are the same), one of XT and X₂ is O whilst the other is NH, RT comprises a continuous carbon chain comprising at least 3 carbon atoms and at least one methyl group (or perfluoromethyl group), and R₂ is either H or a group that is free of any methyl groups (or perfluoromethyl groups) , with the optional exception of a single terminal methyl group attached to a heteroatom, free of any continuous carbon chains comprising 3 or more carbon atoms, and comprises one or more heteroatoms (preferably one or more oxygen atoms).

[00124] RT may comprise a (perfluorocarbon group that is part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide, suitably wherein the copolymer compound is otherwise free of fluorine atoms. M₁ may comprises a (per)fluorocarbon ester wherein the alcohol portion of the ester comprises or consists of a (per)fluorocarbon group whilst the carboxylic acid portion of the ester is free of any fluorine atoms.

[00125] RT may comprise a siloxane (suitably methyl siloxane moiety or perfluoromethyl siloxane moiety) group that is part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide, suitably wherein the copolymer compound is otherwise free of fluorine atoms. M₁ may comprise an ester whose alcohol portion of the ester comprises or consists of a siloxane group whilst the carboxylic acid portion of the ester is free of any silicon atoms.

[00126] In an embodiment, M₁ is selected from the group consisting of TMHA, TMHMA (the methacrylate analog of TMHA), EHA, iOA, TMSMA, HFBMA, or a combination thereof, wherein TMHA, EHA, iOA, TMSMA, and HFBMA have the structures:

[00127] In an embodiment, M₁ is selected from the group consisting of TMHA, EHA, iOA, TMSMA, and HFBMA. In an embodiment, M₁ is selected from the group consisting of TMHA, EHA, and iOA. In a preferred embodiment, M₁ is TMHA. In a particular embodiment, M₁ is TMHMA.

[00128] In an embodiment, M₂ is selected from the group consisting of PEGA, AA, PEGMA, MAA, GMA, or a combination thereof, wherein PEGA, AA, PEGMA, MAA, and GMA have the structures:

[00129] In an embodiment, M₂ is selected from the group consisting of PEGA, AA, PEGMA, MAA, and GMA. In a preferred embodiment, M₂ is PEGA.

[00130] In an embodiment, M₁ is selected from the group consisting of TMHA, TMHMA, EHA, iOA, TMSMA, and HFBMA, and M₂ is selected from the group consisting of PEGA, AA, PEGMA, MAA, and GMA. In an embodiment, M₁ is selected from the group consisting of TMHA, TMHMA, EHA, and iOA, and M₂ is selected from the group consisting of PEGA, AA, PEGMA, MAA, and GMA. In a preferred embodiment, M₁ is TMHA and M₂ is PEGA. In an alternative embodiment, M₁ is TMHMA and M₂ is PEGMA. [00131] Suitably the weight ratio of M₁ to M₂ in the copolymer compound (which may be calculated by reference to inputs into a corresponding polymerisation reaction (i.e. feed ratio), or by reference to NMR spectra to assess the mass fractions in the actual products) is between 20:1 and 1 :20, preferably between 10:1 and 1 :10, preferably between 5:1 and 1 :5, more preferably between 3:1 and 1 :3, most preferably between 2:1 and 1 :2.

[00132] Suitably, the copolymer compound has a number average molar mass (Mn) between 0.5 and 200 kg/mol, preferably between 1 and 100 kg/mol, preferably between 2 and 50 kg/mol, more preferably between 5 and 30 kg/mol, most preferably between 9 and 21 kg/mol. In a particular embodiment, the number average molar mass (Mn) was between 15 and 20 kg/mol.

[00133] In an embodiment, the copolymer compound has a number average molar mass (Mn) between 1 and 30 kg/mol, suitably between 2 and 20 kg/mol.

[00134] In a particular embodiment, the copolymer compound has a number average molar mass (Mn) between 10 and 15 kg/mol, especially where the copolymer is TMHA-stat-PEGA. In a particular embodiment, the copolymer compound has a number average molar mass (Mn) between 8 and 13 kg/mol, especially where the copolymer is TMHA-stat-PEGA.

[00135] Suitably, the copolymer compound has a dispersity (D, D-stroke) value between 1 and 5, suitably between 1.5 and 3, most preferably between 1 .9 and 2.6. In a particular embodiment, dispersity value is between 2.25 and 2.45. In a particular embodiment, the copolymer compound has a dispersity (D, D-stroke) value between 1 and 3, suitably between 1 .2 and 2.5. Suitably the dispersity (DM) is calculated as follows:

where M_w is the weight average molar mass and M_n is the number-average molar mass.

[00136] In a particular embodiment, the polydispersity is between 1 and 2.2. In a particular embodiment, the polydispersity is between 1.5 and 2.1.

[00137] According to a further aspect of the present invention there is provided a method of manufacturing a copolymer compound. The method suitably comprises mixing together polymerizable monomers to form a reaction mixture, and initiating polymerisation. The method suitably comprises mixing together solvophobic monomer(s) with solvophilic monomer(s) (suitably in a desired ratio to furnish a desired solvophilic-solvophobic balance) and initiating polymerisation thereof. The method suitably comprises mixing together monomers of formula M₁ (suitably as defined herein) with monomers of formula M₂ (suitably as defined herein), optionally with further monomers of formula M_n (suitably as defined herein), to form a reaction mixture, an initiating polymerisation thereof. The reaction mixture suitably further comprises a solvent system. The solvent system may be a polar solvent system, such as an alcoholic solvent system (e g. ethanolic). Suitably, the monomers are present within the reaction mixture at a combined concentration of between 1 wt% and 50 wt%, more preferably between 5 wt% and 30 wt%, most preferably between 15 and 25 wt%. In an embodiment, the monomers are present within the reaction mixture at a combined concentration of about 20 wt%.

[00138] Initiation and polymerisation conditions may be judiciously chosen by those skilled in the art based inter alia on the nature of the relevant monomers (including the nature of the polymer backbone formed therefrom).

[00139] In an embodiment, initiating polymerisation is caused by thermal initiation, redox initiation, and/or photolytic initiation. In an embodiment, initiating polymerisation is caused by thermal initiation. Suitably, in addition to the monomers, the reaction mixture may be provided with an initiator (suitably mixed with the monomers) to facilitate initiation of polymerisation. Said initiator may be a thermal initiator, a redox initiator, and/or a photolytic initiator. The initiator is suitably present within the reaction mixture at a concentration of between 0.0001 wt%% and 5 wt%, preferably at a concentration of between 0.01 wt% and 2 wt%, most preferably between 0.5 wt% and 1.5 wt%. In an embodiment, the initiator is present within the reaction mixture at a concentration of about 1 wt%. In an embodiment, the initiator is a thermal initiator such as, for example, azobisisobutyronitrile (AIBN).

[00140] Polymerisation suitably involves statistical or random polymerisation of the monomers in the reaction mixture. The polymerisation is suitably performed at elevated temperatures, suitably at a temperature between 25 and 200°C, 40 and 150 °C, more suitably between 50 and 100°C, most suitably between 60 and 80°C. Prior to elevating the temperature of the reaction mixture to induce polymerisation, the reaction mixture is homogenised, suitably via stirring.

[00141] Polymerisation may suitably be free-radical polymerisation (FRP). Alternatively, polymerisation may suitably be a reversible deactivation radical polymerisation (RDRP) - for instance polymerisation may be atom transfer radical polymerisation (ATRP) or reversible addition-fragmentation chain-transfer polymerisation (RAFT).

[00142] Following polymerisation, which may take at least 2 hours at elevated temperature, suitably at least 4 hours at elevated temperature, the copolymer compound is isolated from the reaction mixture, suitably via removal of the solvent system. The copolymer compounds may then be optionally further purified.

[00143] The copolymer compounds are suitably dried, suitably before any subsequent use. However, copolymer compounds may be used, for instance in hand-sanitizers, directly from their reaction-formation mixtures, for instance when the reaction solvent is or comprises ethanol, wherein said reaction-formation mixture may optionally be concentrated (e g. in vacuo) or further diluted (e g. with ethanol and/or water) prior to subsequent use.

[00144] The copolymer compounds may be suitably characterised by ¹H NMR and/or GPC.

[00145] In an embodiment, the copolymer compound is a compound of Formula la: poly(M₁-co-M₂), wherein is or is derived from a solvophobic monomer comprising a solvophobic pendent group, R_1: wherein at least 100 parts by mass of water is required to dissolve 1 part by mass of Mi, and M₂ is or is derived from a solvophiilic monomer comprising a solvophiilic pendent group, R₂, wherein at most 30 parts by mass of water is required to dissolve 1 part by mass of M₂; wherein the copolymer compound optionally comprises further monomers, M_n, on the proviso that monomers and M₂ constitute at least 70% of the monomer units of the copolymer compound.

[00146] In an embodiment, the copolymer compound is a compound of Formula la: poly(M₁-co-M₂), wherein is or is derived from a solvophobic monomer comprising a solvophobic pendent group, R_{1 :} wherein has a logP value greater than 1 .5 (suitably greater than 3), and M₂ is or is derived from a solvophilic monomer comprising a solvophilic pendent group, R₂, wherein M₂ has a logP value less than 1.5 (suitably less than 0); wherein the copolymer compound optionally comprises further monomers, M_n, on the proviso that monomers and M₂ constitute at least 70% of the monomer units of the copolymer compound.

[00147] The following numbered paragraphs A1 to A28 disclose specific embodiments of the copolymer compound.

A1. A copolymer compound of Formula la: poly(M₁-co-M₂), wherein is (or in the context of the polymer is derived from) a solvophobic monomer and M₂ is a solvophiilic monomer.

A2. The copolymer compound of A1 further defined by Formula Ila: poly(M₁-stat-M₂).

A3. The copolymer compound of A1 or A2, wherein and M₂ have complementary mass fractions (which together total 1) of 0.25-0.75 for and 0.75-0.25 for M₂, more preferably 0.33-0.66 for and 0.66-0.33 for M₂.

A4. The copolymer compound of A1 to A3, wherein the weight ratio of to M₂ in the copolymer compound is between 3:1 and 1 :3, most preferably between 2:1 and 1 :2.

A5. The copolymer compound of any of A1 to A4, wherein the copolymer compound has a number average molar mass (M_n) between 2 and 30 kg/mol, most preferably between 9 and 21 kg/mol.

A6. The copolymer compound of any of A1 to A5, wherein the copolymer compound has a dispersity (D, D-stroke) value between 1.3 and 3, most preferably between 1.9 and 2.6.

A7. The copolymer compound of any of A1 to A6, wherein the monomers and M₂ constitute at least 90% of the monomer units of the copolymer compound, more preferably (substantially) 100% of the monomer units of the copolymer compound.

A8. The copolymer compound of any of A1 to A7, wherein the copolymer compound has an HLB value between 5 and 15.

A9. The copolymer compound of any of A1 to A8, wherein has a logP value greater than 1.5 (suitably greater than 3, more suitably greater than 4) and M₂ has a logP value less than 1.5 (suitably less than 1 , more suitably less than 0). A10. The copolymer compound of any of A1 to A9, wherein at least 1000 parts by mass of water are required to dissolve 1 part by mass of Mi, and at most 10 parts by mass of water are required to dissolve 1 part by mass of M₂.

A11 . The copolymer compound of any of A1 to A10, wherein the copolymer compound comprises a polymeric backbone selected from the group consisting of a polyvinyl backbone, a polyester backbone, a polyalkylene (e g. polyethylene or polypropylene) backbone, a polyacrylic backbone, a polyalkylacrylic (e g. polymethacrylic) backbone, and a polyoxyalkylene (e g. polyoxyethylene or polyoxypropylene) backbone, or mixed (heterogeneous) backbone comprising two or more of the aforesaid backbones (e g. mixed polyacrylic- polymethacrylic backbone).

A12. The copolymer compound of A11 , wherein the copolymer compound has a homogeneous polyacrylic backbone or a homogeneous polyalkylacrylic backbone.

A13. The copolymer compound of any of A1 to A12, wherein the copolymer compound is defined by Formula Iva or Formula Va:

wherein RT is a pendent solvophobic group (suitably a non-polar group), R₂ is a pendent solvophilic group (a polar group, especially relative to RT), BT and B₂’ are reacted (polymerised) backbone portions, and Q1 and Q₂ represent the remainder of the respective monomeric units.

A14. The copolymer compound of any of A1 to A13, wherein M₁ is a monomer having the formula M_1A:

wherein R_B1 is either H or a (1 -2C)alkyl (e g. methyl), XT is O or NH, and RT is a pendent solvophobic (typically hydrophobic) group, suitably as defined hereinbefore or hereinafter; and M₂ is a monomer having the formula M_a:

wherein R_B2 is either H or a (1 -2C)alkyl (e g. methyl), X₂ is O or NH, and R₂ is a pendent solvophilic (typically hydrophlic) group, suitably as defined hereinbefore or hereinafter.

A15. The copolymer compound of any of A13, and A14, wherein RT comprises at least one methyl (CH₃) group.

A16. The copolymer compound of any of A13 to A15, wherein RT comprises a continuous carbon chain comprising at least 3 carbon atoms and at least one methyl group (or perfluoromethyl group).

A17. The copolymer compound of any of A13 to A16, wherein R₂ is free of methyl groups (optionally with the exception of terminal methyl groups, especially where attached to a heteroatom and especially where there is only a single terminal methyl group, such as may be the case for PEGA and PEGMA; or optionally except where said methyl group is attached to a heteroatom).

A18. The copolymer compound of any of A13 to A17, wherein R₂ is either H or a group that is free of any methyl groups (or perfluoromethyl groups), with the optional exception of a single terminal methyl group attached to a heteroatom, free of any continuous carbon chains comprising 3 or more carbon atoms, and comprises one or more heteroatoms (preferably one or more oxygen atoms).

A19. The copolymer compound of any of A13 to A18, wherein R₂ comprises at least one heteroatom (e.g. O or N, preferably O, such as OH, ester, or ether moieties), suitably at least two heteroatoms, more suitably at least three heteroatoms, most suitably at least four heteroatoms, suitably wherein R₂ has a chain length of at least 3, suitably at least 5, suitably at least 7.

A20. The copolymer compound of A14 or any of A15 to A19 when dependent on A14, wherein R_B1 and R_B2 are independently H or CH₃ (though preferably R_B1 and R_B2 are the same), and X₂ are both O, comprises a continuous carbon chain comprising at least 3 carbon atoms and at least one methyl group (or perfluoromethyl group), and R₂ is either H or a group that is free of any methyl groups (or perfluoromethyl groups), with the optional exception of a single terminal methyl group attached to a heteroatom, free of any continuous carbon chains comprising 3 or more carbon atoms, and comprises one or more heteroatoms (preferably one or more oxygen atoms).

A21. The copolymer compound of A13 to A20, wherein comprises a (perfluorocarbon group that is part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide, suitably wherein the copolymer compound is otherwise free of fluorine atoms.

A22. The copolymer compound of A1 to A21 wherein comprises a (perfluorocarbon ester wherein the alcohol portion of the ester comprises or consists of a (per)fluorocarbon group whilst the carboxylic acid portion of the ester is free of any fluorine atoms.

A23. The copolymer compound of A13 to A22, wherein comprises a siloxane (suitably methyl siloxane moiety or perfluoromethyl siloxane moiety) group that is part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide, suitably wherein the copolymer compound is otherwise free of silicon atoms.

A24. The copolymer compound of A1 to A23, wherein comprises an ester whose alcohol portion of the ester comprises or consists of a siloxane group whilst the carboxylic acid portion of the ester is free of any silicon atoms.

A25. The copolymer compound of any of A1 to A24, wherein is selected from the group consisting of TMHA, TMHMA, EHA, iOA, TMSMA, and HFBMA.

A26. The copolymer compound of any of A1 to A25, wherein is TMHA.

A27. The copolymer compound of any of A1 to A26, wherein M₂ is selected from the group consisting of PEGA, AA, PEGMA, MAA, and GMA.

A28. The copolymer compound of any of A1 to A27, wherein M₂ is PEGA.

[00148] The following numbered paragraphs B1 to B13 are specific embodiments of the copolymer compound (NB. as a skilled person will appreciate, the formulas are generally formatted to correspond to poly(M₂-stat-M₁), i.e. with and M₂ reversed compared to other notations), which may in addition (and where applicable) have additional features as defined in any of A1 to A28:

B1. A copolymer compound of Formula poly(PEGA-stat-EHA). In an embodiment, the weight ratio of PEGA:EHA is 1 :1. In another embodiment, the weight ratio of 3:2.

B2. A copolymer compound of Formula poly(PEGA-stat-EHMA). In an embodiment, the weight ratio of PEGA:EHMA is 1 :1. EHMA is the methacrylate corresponding to the acrylate of EHA.

B3. A copolymer compound of Formula poly(PEGA-stat-TMHA). In an embodiment, the weight ratio of PEGA:TMHA is 2:1. In an embodiment, the weight ratio of PEGA:TMHA is 3:2. In an embodiment, the weight ratio of PEGA:TMHA is 1 :1 . In an embodiment, the weight ratio of PEGA:TMHA is 2:3. In an embodiment, the weight ratio of PEGA:TMHA is 1 :2. In an embodiment, the weight ratio of PEGA:TMHA is between 2:1 and 1 :2.

B4. A copolymer compound of Formula poly(PEGMA-stat-TMHA). In an embodiment, the weight ratio of PEGMA:TMHA is 1 :1.

B5. A copolymer compound of Formula poly(PEGMA-stat-TMHMA). In an embodiment, the weight ratio of PEGA:TMHMA is 2:1. In an embodiment, the weight ratio of PEGA:TMHMA is 3:2. In an embodiment, the weight ratio of PEGA:TMHMA is 1 :1 . In an embodiment, the weight ratio of PEGA:TMHMA is 2:3. In an embodiment, the weight ratio of PEGA:TMHMA is 1 :2. In an embodiment, the weight ratio of PEGA:TMHMA is between 2:1 and 1 :2.

B6. A copolymer compound of Formula poly(PEGA-stat-iOA). In an embodiment, the weight ratio of PEGA:iOA is 1 :1. B7. A copolymer compound of Formula poly(GMA-stat-TMHA). In an embodiment, the weight ratio of GMA:TMHA is 3:2. In an embodiment, the weight ratio of GMA:TMHA is 1 :1 . In an embodiment, the weight ratio of GMA:TMHA is 2:3.

B8. A copolymer compound of Formula poly(AA-stat-TMHA). In an embodiment, the weight ratio of AA:TMHA is 3:2. In an embodiment, the weight ratio of AA:TMHA is 1 :1. In an embodiment, the weight ratio of AA:TMHA is 2:3.

B9. A copolymer compound of Formula poly(PEGMA-stat-TMSMA). In an embodiment, the weight ratio of PEGMA:TMSMA is 2:3. In an embodiment, the weight ratio of PEGMA:TMSMA is 3:2.

B10. A copolymer compound of Formula poly(MAA-stat-TMSMA). In an embodiment, the weight ratio of MAA:TMSMA is 2:3. In an embodiment, the weight ratio of MAA:TMSMA is 1 :1. In an embodiment, the weight ratio of MAA:TMSMA is 3:2.

B11 . A copolymer compound of Formula poly(MAA-stat-HFBMA). In an embodiment, the weight ratio of MAA: HFBMA is 2:3. In an embodiment, the weight ratio of MAA: HFBMA is 1 :1. In an embodiment, the weight ratio of MAA: HFBMA is 3:2. In an embodiment, the weight ratio of MAA: HFBMA is 1 :2.

B12. A copolymer compound of Formula poly(PEGMA-stat-HFBMA). In an embodiment, the weight ratio of PEGMA: HFBMA is 1 : 1 . In an embodiment, the weight ratio of PEGMA: HFBMA is 1 :2.

B13. A copolymer compound of Formula poly(PEGA-stat-LA), where LA is lauryl acrylate. In an embodiment, the weight ratio of PEGA: LA is 1 :1.

[00149] It will be appreciated that any of the aforesaid weight ratios may be represented as mass fractions for each respective monomer where the sum of mass fractions for the two stipulated monomers total 1. For example, a max fraction of 3:2 equates to a mass fraction for the first-referenced monomer of 0.6 and a mass fraction for the second-referenced monomer of 0.4.

[00150] An example of a copolymer compound of the invention having a non-acrylate-based polymer backbone is PEO- stat-PBO (i.e. polyethyleneoxide-stat-polybutyleneoxide). Another example is poly(styrene-co-maleic anhydride).

FOAMABLE COMPOSITION and FOAMED COMPOSITION

[00151] The present invention provides a foamable composition, and a foamed composition, suitably as defined herein. Suitably the foamed composition is formed by causing the foamable composition to foam, for instance, by introducing a gas (such as air) or other bubble-forming substance into the foamable composition. Sometimes the foamed composition is formed from the foamable composition after, during, or before dispensation.

[00152] The present invention also provides a foamable concentrate composition, which may suitably act as a precursor to the foamable composition or indeed the foamed composition. The foamable concentrate composition comprises the copolymer compound, as defined herein. The foamable concentrate composition suitably comprises all ingredients present within the ultimate foamable composition, optionally excluding (or with a relatively reduced quantity of) the solvent system of the foamable composition. The foamable composition is suitably formed by mixing together the foamable concentrate composition and the solvent system. In some embodiments, mixing together the foamable concentrate and the solvent system is performed simultaneously with, or just prior to, foaming (or aspiration with a gas), such that the foamed composition may be formed (substantially) directly.

Foamable Composition

[00153] According to a further aspect of the present invention there is provided a foamable composition, suitably as defined herein. The foamable composition is suitably a liquid or a gel prior to foaming. Most suitably the foamable composition is a liquid, albeit the liquid may be a viscous liquid. In an embodiment, the foamable composition is a free-flowing liquid composition. The foamable composition preferably comprises the aforementioned copolymer compound. The foamable composition preferably comprises a foaming medium or solvent system. Preferably the solvent system is a polar solvent system. In an embodiment, the foamable composition comprises one or more foamable components and a copolymer compound. The one or more foamable components may comprise a foaming medium or solvent system. The one or more foamable components may comprise a mixture of components, optionally comprising a foaming medium or solvent system. The foamable components may comprise a foamable polymer or one or more foamable polymerizable monomer(s).

[00154] The copolymer surfactants are suitably copolymer compounds as defined herein. The foamable composition preferably comprises a copolymer compound. Whilst the copolymer compound may in fact be one or more, possibly two or more copolymer compounds, most preferably the copolymer compound is a single copolymer compound (i.e. suitably the foamable composition comprises a single copolymer compound).

[00155] Suitably the copolymer compound is as defined hereinbefore in the section entitled “COPOLYMER COMPOUND”. The copolymer compound is preferably a copolymer as defined in any of numbered paragraphs A1 to A28. In particular embodiments, the copolymer compound is defined in numbered paragraphs B1 to B13, and optionally further defined as per any of numbered paragraphs A1 to A28.

[00156] The copolymer compound is suitably present in the foamable composition at a concentration between 0.01 and 20 wt%, preferably between 0.1 and 10 wt%, more preferably between 0.5 and 5 wt%, most preferably between 1.5 and 4 wt%. In a particular embodiment, the copolymer compound is present in the foamable composition at a concentration between 2 and 4 wt%. In a particular embodiment, the copolymer compound is present in the foamable composition at a concentration between 2 and 3 wt%. In an embodiment, the copolymer compound is suitably present in the foamable composition at a concentration between 0.5 and 2 wt%.

[00157] Suitably the copolymer compound is dissolved within and/or dispersed within the polar solvent system. Most suitably, dissolved and/or dispersed copolymer compound exists in solution (and/or in dispersion) as a single-molecular micelle, though suitably the copolymer compound may be present at any surface interfaces in non-micellular form. Preferably at least 50 wt% of the dissolved (or dispersed) copolymer compound exists as a single-molecular micelle, more preferably at least 70 wt%, more preferably at least 90 wt%, most preferably at least 95 wt%. Preferably at most 50 wt% of the dissolved (or dispersed) copolymer compound exists as a multi-molecular micelle, more preferably at most 30 wt%, more preferably at most 10 wt%, most preferably at most 5 wt%.

[00158] Suitably, when stabilising foams, the copolymer compound migrates to a surface interface and self-assembles (e g. through unfolding and/or refolding) so as to orientate solvophilic groups (e g. pendant groups of a solvophilic monomer, M₂, such as R₂ groups thereof) towards or into the solvent system and to orientate solvophobic groups (e g. pendant groups of a solvophobic monomer, Mi, such as RT groups thereof) away from the solvent system, generally into a gas bubble.

[00159] The exact solvent system and copolymer compound may vary according to the specific application envisaged for the foamable compositions. Suitably, the foamable composition is a personal care composition (e g. hand-sanitizer), a firefighting composition, or a foamable polymerizable composition (e g. a precursor composition for forming polyurethane foams).

[00160] The foaming medium or solvent system suitably constitutes the balance of any foamable composition, once the copolymer compound any other additives are accounted for. Suitably, the solvent system is present within the foamable composition at a concentration of 50 to 99.99 wt%, 60 to 99.5 wt%, more suitably 70 to 99 wt%, more suitably 80 to 99 wt%, most suitably 90 to 98 wt%.

[00161] The solvent system suitably comprises at least 10 wt% water, more suitably at least 20 wt% water, most suitably at least 30 wt% water. The solvent system suitably comprises 10-100 wt% water, suitably 20-95 wt%, suitably 30 to 90 wt% water.

[00162] In an embodiment, the solvent system comprises 25 to 50 wt% water. In an embodiment, the solvent system comprises 30 to 40 wt% water.

[00163] In an embodiment, the solvent system comprises 70 to 95 wt% water. In an embodiment, the solvent system comprises 80 to 90 wt% water.

[00164] In an embodiment, the solvent system consists of water. [00165] In an embodiment, the solvent system comprises water and an organic solvent, suitably a polar organic solvent or an organic solvent that is substantially miscible in water (suitably without the aid of additives, such as surfactants). The polar organic solvent suitably has a dielectric constant (or relative permittivity) greater than or equal to 5, suitably greater than or equal to 10, more suitably greater than or equal to 15, most suitably greater than or equal to 20. The polar organic solvent may suitably be an aprotic or protic polar organic solvent. The polar organic solvent is suitably selected from the group consisting of methanol, ethanol, n-propanol, /so-propanol, n-butanol, acetic acid, acetone, dimethylformamide, acetonitrile, dimethylsulphoxide, nitromethane, glycerol, ethylene glycol, propylene glycol, and propylene carbonate. Most suitably, the polar organic solvent is a protic organic solvent. The protic organic solvent is most suitably selected from the group consisting of methanol, ethanol, n-propanol, /'so-propanol, n-butanol, and acetic acid. In an embodiment, the protic organic solvent is an alcohol, most suitably a (1-4C)alcohol, most suitably a (2-3C)alcohol. In an embodiment, the polar organic solvent is ethanol, n-propanol, or /'so-propanol. In a preferred embodiment, the polar organic solvent is ethanol.

[00166] Suitably, the solvent system is an alcoholic solvent system. The solvent system may suitably comprise 10-90 wt% alcohol (e.g. ethanol), more suitably 40-80 wt% alcohol, more suitably 50-75 wt% alcohol, more suitably 60-70 wt% alcohol (e.g. ethanol). In an embodiment, the solvent system comprises 53-73 wt% alcohol. In an embodiment, the solvent system comprises 60-70 wt% alcohol. Suitably the balance of any of these alcoholic solvent systems is water.

[00167] The solvent system comprising water and an organic solvent suitably comprises water at a concentration as defined herein. The organic solvent may be one or more organic solvents, though most preferably the organic solvent is a single organic solvent.

[00168] The solvent system comprising water and an organic solvent is suitably a solvent system consisting of water and an organic solvent.

[00169] The solvent system comprising water and an organic solvent may suitably comprise water and the organic solvent in a weight ratio of between 1 :99 and 99:1 (i.e. between 1 wt% water and 99 wt% water), more suitably between 1 :9 and 9:1 , more suitably between 3:7 and 7:3, most suitably between 3:7 and 1 :1.

[00170] Surface tensions (y) defined herein are suitably given in mN/m (millinewtons per meter)) at SATP unless otherwise stated. The solvent system suitably has a higher surface tension than the foamable composition (i.e. when the solvent system is mixed with a copolymer compound, suitably as defined herein). As such, the copolymer compound suitably lowers the surface tension of the solvent system, when the copolymer compound is mixed therewith. The surface tension of the solvent system is suitably between 5 and 90 mN/m. The surface tension of the solvent system is suitably at or below 90 mN/m, suitably at or below 80, suitably at or below 60, suitably at or below 40, suitably at or below 30. The surface tension of the solvent system is suitably at least 5 mN/m, suitably at least 10, suitably at least 15, suitably at least 20, suitably at least 25. In a particular embodiment, the solvent system has a surface tension between 20 and 35 mN/m, suitably between 25 and 30 mN/m.

[00171] The surface tension of the foamable composition is suitably between 5 and 90 mN/m. The surface tension of the foamable composition is suitably at or below 80 mN/m, suitably at or below 70, suitably at or below 50, suitably at or below 40, suitably at or below 30. The surface tension of the foamable composition is suitably at least 5 mN/m, suitably at least 10, suitably at least 15, suitably at least 20, suitably at least 25.

[00172] The copolymer compound suitably lowers the surface tension of the solvent system, when mixed therewith to furnish a foamable composition with a relevant concentration of said copolymer compound (suitably as defined herein), by between 0.1 and 50 mN/m, suitably by between 1 and 20 mN/m, suitably by between 2 and 10 mN/m.

[00174] Suitably, the advantageous properties of foamable compositions of the invention are substantially unaffected by ionic strength, especially ionic strengths between 0 and 1.0 M (e.g. between 0 and 1 M NaCI). [00175] According to a further aspect of the present invention there is provided a foamable composition dispenser (or a foam dispenser), comprising a reservoir or reservoir inlet (connectable to a reservoir), a dispensing nozzle, and a fluid connection (e g. conduit, pipe, or tube) between the reservoir or reservoir inlet and the dispensing nozzle. The reservoir suitably comprises a foamable composition (suitably as defined herein), and the dispensing nozzle is suitably operable or configured (manually or automatically, optionally in response to a detection signal) to dispense the foamable composition from the reservoir or reservoir inlet and out through the dispensing nozzle.

[00176] According to a further aspect of the present invention there is provided a foamable composition dispenser, comprising a reservoir, a dispensing nozzle, and a fluid connection (or conduit) between the reservoir and the dispensing nozzle. The reservoir suitably comprises a foamable composition (suitably as defined herein), and the dispensing nozzle is suitably operable or configured (manually or automatically, optionally in response to a detection signal) to dispense the foamable composition from the reservoir and out through the dispensing nozzle. The dispensing nozzle may be manually actuated, for example by pump action. Alternatively, the dispensing nozzle may be manually actuated by releasing a valve so that the foamable composition is dispensed out of the dispensing nozzle under pressure (suitably under pressure by a pressurized reservoir). The dispensing nozzle may be specially adapted to promote foaming of the foamable composition as the latter is dispensed through the nozzle. Alternatively or additionally, the dispenser may comprise a foam-forming component, suitably en route between the reservoir and the nozzle, which causes the foamable composition to transform (partially or completely) into a foamed composition, suitably prior to exiting (and/or prior to reaching) the nozzle.

[00177] According to a further aspect of the present invention there is provided a method of manufacturing a foamable composition, suitably as defined herein. The method suitably comprises mixing a copolymer compound with a solvent system, optionally with any other additives required in the foamable composition (which, in the case of PU foams may include a polymer, such as PU polymer, suitably in a hot liquid state). The method may comprise initially forming a foamable concentrate composition, wherein said concentrate comprises the copolymer compound, and suitably also comprises all other relevant ingredients that may desirably be present in the final composition, and mixing said foamable concentrate composition with the solvent system to thereby form the foamable composition.

[00178] The following numbered paragraphs C1 to C14 disclose specific embodiments of the foamable composition:

C1. A foamable composition comprising a copolymer compound (suitably as defined herein) and a solvent system (suitably as defined herein).

C2. The foamable composition of C1 , wherein the copolymer compound is a single copolymer compound.

C3. The foamable composition of C1 , or C2, wherein the copolymer compound is as defined in any of numbered paragraphs A1 to A28.

C4. The foamable composition of C1 , C2, or C3, wherein the copolymer compound is as defined in numbered paragraphs B1 to B13, and optionally further defined as per any of numbered paragraphs A1 to A28.

C5. The foamable composition of C1 , C2, C3, or C4, wherein the copolymer compound lowers the surface tension of the solvent system, when mixed therewith to furnish a foamable composition with a relevant concentration of said copolymer compound (suitably as defined herein), by between 1 and 50 mN/m.

C6. The foamable composition of C1 , C2, C3, C4, or C5, wherein the surface tension of the solvent system is between 20 and 35 mN/m, preferably between 25 and 30 mN/m.

C7. The foamable composition of C1 , C2, C3, C4, C5, or C6, wherein the solvent system comprises 10-100 wt% water.

C8. The foamable composition of C1 , C2, C3, C4, C5, C6, or C7, wherein the solvent system comprises water and an organic solvent.

C9. The foamable composition of C8, wherein the organic solvent is a single organic solvent.

C10. The foamable composition of C8 or C9, wherein the solvent system comprises water and the organic solvent in a weight ratio of between 1 :9 and 9:1 , preferably between 3:7 and 7:3.

C11. The foamable composition of C8, C9, or C10, wherein the organic solvent is a polar organic solvent having a dielectric constant greater than or equal to 15.

C12. The foamable composition of C8, C9, C10, or C11 , wherein the polar organic solvent is an alcohol.

C13. The foamable composition of C12, wherein the alcohol is a (2-3C)alcohol, preferably ethanol. C14. The foamable composition of C12 or C13, wherein the solvent system comprises 50-75 wt% alcohol, wherein suitably the balance of the solvent system is water.

[00179] In a particular embodiment, the foamable composition is a liquid comprising a copolymer compound and a solvent system, wherein the composition is (substantially) free of foam or, if a small amount of foam is present, said foam is present in a volumetric ratio of foam to liquid of 1 :10 or lower (i.e. 0-1 :10), more suitably 1 :100 or lower, more suitably 1 :1000 or lower.

[00180] In a particular embodiment, the foamable composition is a liquid comprising 0.1-5 wt% copolymer compound, and a solvent system.

[00181] In a particular embodiment, the foamable composition is a liquid comprising 0.1-10 wt% copolymer compound, a solvent system which comprises at least 20 wt% water (suitably at least 25 wt% water), and one or more further additives at a concentration of at least 0.1 wt%, suitably at most 1 wt%.

[00182] The embodiments and features disclosed in this section may preferably be combined with any of embodiments A1 to A28 and/or B1 to B13. The embodiments and features disclosed in this section may preferably be combined with any embodiments and features disclosed in any other section herein.

Foamed Composition

[00183] According to a further aspect of the present invention there is provided a foamed composition, suitably as defined herein. The foamed composition may alternatively be termed “a foam”. The foamed composition preferably comprises the aforementioned copolymer compound.

[00184] Suitably, the foamed composition is a foamed form of the aforementioned foamable composition.

[00185] In terms of formulation (or ingredients), the foamed composition is suitably (substantially) identical to the foamable composition as defined herein. The foamed composition is suitably identical to the foamable composition but with bubbles, suitably gas bubbles. However, the foamed composition or foam may be a wet foam or a (substantially) dry foam. As such, the foamed composition may be (substantially) identical to the foamable composition but with between 0 and 100 wt% of the solvent system removed, suitably between 0 and 80 wt%, suitably between 0 and 50 wt%, suitably between 0 and 30 wt%. As such, the foamed composition is suitably defined as per the foamable composition, suitably as defined in any of numbered paragraphs C1 to C14, suitably additionally comprising bubbles (suitably gas bubbles), and optionally with between 0 and 100 wt% of the solvent system removed.

[00186] According to a further aspect of the present invention there is provided a method of manufacturing a foamed composition, suitably as defined herein. According to a further aspect of the present invention there is provided a method of generating a foam, suitably as defined herein, suitably from a foamable composition. Such a method preferably comprises foaming the aforesaid foamable composition.

[00187] Foaming of the foamable composition, to form the foamed composition, may be suitably performed by contacting the foamable composition with a bubbling agent. The bubbling agent is suitably a liquid or a gas (or a substance capable of producing said liquid orgas, suitably in situ) capable of forming bubbles within the foamable composition under the prevailing conditions. Foaming may be caused by aspirating the foamable composition, for instance by aerating or otherwise introducing air into the foamable composition. Suitably, surface active agents facilitate foaming. The copolymer compound may be a surface active agent that facilitates foaming. Suitably, foam-stabilising agents stabilise the foam, once it has formed or during its formation. Suitably, the copolymer compound is a foam-stabilising agent that stabilises the foam.

[00188] According to a further aspect of the present invention there is provided a foamed composition dispenser, comprising a reservoir, a dispensing nozzle, and a fluid connection (or conduit) between the reservoir and the dispensing nozzle. The reservoir suitably comprises a foamed composition (suitably as defined herein), and the dispensing nozzle is suitably operable or configured (manually or automatically, optionally in response to a detection signal) to dispense the foamed composition from the reservoir and out through the dispensing nozzle. Alternatively, the reservoir suitably comprises a foamable composition (suitably as defined herein), and the dispenser is operable (optionally via the nozzle) to dispense a foamed composition or a foamable composition that foams during or after exiting the dispenser. The dispenser may be comprise a foam-forming component (e g. foaming-forming branch), suitably en route between the reservoir and the nozzle, which causes the foamable composition to foam and thereby (partially or completely) transform into a foamed composition, suitably prior to exiting (and/or prior to reaching) the nozzle.

[00189] The foam suitably subsists for at least 2 seconds, suitably for at least 5 seconds, suitably for at least 20 seconds, suitably for at least 60 seconds.

[00190] The foam may comprise substantial quantities of foamable composition in between the bubbles of the foam (e g. a wet foam). A quantity of unfoamed foamable composition may still be present after dispensing the foamed composition.

Personal Care Composition / Hand-Sanitizing Composition

[00191] According to a further aspect of the present invention there is provided a foamable personal care composition, suitably as defined herein. Suitably, the aforementioned foamable composition is a foamable personal care composition. Suitably the foamable personal care composition is a hand-sanitizer (or hand-sanitizing composition).

[00192] According to a further aspect of the present invention there is provided a hand-sanitizer dispenser, comprising a reservoir, a dispensing nozzle, and a fluid connection (or conduit) between the reservoir and the dispensing nozzle. The reservoir suitably comprises a hand-sanitizing composition (suitably as defined herein), and the dispensing nozzle is suitably operable or configured (manually or automatically, optionally in response to a detection signal) to dispense the handsanitizing composition from the reservoir and out through the dispensing nozzle. The dispensing nozzle may be manually actuated, for example by pump action. The dispensing nozzle may be specially adapted to promote foaming of the handsanitizing composition as the latter is dispensed through the nozzle.

[00193] Whilst the foamable personal care composition (or hand-sanitizing composition) may be defined by any of the features or embodiments disclosed herein in relation to a foamable composition, including those of numbered paragraphs C1 to C14, the following numbered paragraphs D1 to D41 disclose specific embodiments of the foamable personal care composition (or hand-sanitizing composition):

D1 . The foamable personal care composition (or hand-sanitizing composition) comprises a copolymer compound and a solvent system, wherein the solvent system comprises water and an organic solvent.

D2. The foamable personal care composition (or hand-sanitizing composition) of D1 , wherein the solvent system is present within the foamable composition at a concentration of 50 to 99.99 wt%, preferably 80 to 99 wt%.

D3. The foamable personal care composition (or hand-sanitizing composition) of D1 or D2, wherein the copolymer compound is present in the composition at a concentration between 0.5 and 5 wt%, preferably between 1 .5 and 4 wt%.

D4. The foamable personal care composition (or hand-sanitizing composition) of D3, wherein the copolymer compound is present in the composition at a concentration between 2 and 4 wt%.

D5. The foamable personal care composition (or hand-sanitizing composition) of D4, wherein the copolymer compound is present in the composition at a concentration between 2 and 3 wt%.

D6. The foamable personal care composition (or hand-sanitizing composition) of D1 to D5, wherein the composition comprises 0.5 and 5 wt% copolymer compound and 80 to 99 wt% solvent system.

D7. The foamable personal care composition (or hand-sanitizing composition) of D1 to D6, wherein the organic solvent is a polar organic solvent having a dielectric constant (or relative permittivity) greater than or equal to 10.

D8. The foamable personal care composition (or hand-sanitizing composition) of D1 to D7, wherein the organic solvent is a polar organic solvent selected from the group consisting of methanol, ethanol, n-propanol, /so-propanol, n- butanol, acetic acid, acetone, dimethylformamide, acetonitrile, dimethylsulphoxide, nitromethane, and propylene carbonate.

D9. The foamable personal care composition (or hand-sanitizing composition) of D1 to D8, wherein the solvent system is an alcoholic solvent system. D10. The foamable personal care composition (or hand-sanitizing composition) of D9, wherein the alcoholic solvent system comprises a (1-4C)alcohol.

D11. The foamable personal care composition (or hand-sanitizing composition) of D10, wherein the alcohol is a (2- 3C)alcohol.

D12. The foamable personal care composition (or hand-sanitizing composition) of D11 , wherein the alcohol is ethanol.

D13. The foamable personal care composition (or hand-sanitizing composition) of D10 to D12, wherein the composition comprises 10-90 wt% alcohol (e.g. ethanol).

D14. The foamable personal care composition (or hand-sanitizing composition) of D13, wherein the composition comprises 50-75 wt% alcohol.

D15. The foamable personal care composition (or hand-sanitizing composition) of D14, wherein the composition comprises 60-70 wt% alcohol (e.g. ethanol).

D16. The foamable personal care composition (or hand-sanitizing composition) of D10 to D15, wherein the composition comprises comprise water and the alcohol (e.g. ethanol) in a weight ratio of between 3:7 and 7:3, most preferably between 3:7 and 1 :1.

D17. The foamable personal care composition (or hand-sanitizing composition) of D1 to D16, wherein the solvent system has a surface tension between 20 and 35 mN/m, preferably between 25 and 30 mN/m.

D18. The foamable personal care composition (or hand-sanitizing composition) of D1 to D17, wherein the copolymer compound is defined according to any of A1 to A28 and/or any of B1 to B13.

D19. The foamable personal care composition (or hand-sanitizing composition) of D1 to D18, wherein the copolymer compound is defined by Formula la: poly(M₁-co-M₂) or by Formula Ila: poly(M₁-stat-M₂), wherein the weight ratio of M₁ to M₂ in the copolymer compound is between 3:1 and 1 :3, preferably between 2:1 and 1 :2.

D20. The foamable personal care composition (or hand-sanitizing composition) of D19, wherein at least 1000 parts by mass of water are required to dissolve 1 part by mass of M₁ and at most 10 parts by mass of water are required to dissolve 1 part by mass of M₂.

D21. The foamable personal care composition (or hand-sanitizing composition) of D1 to D18, wherein the copolymer compound comprises a solvophobic monomer M₁ and a solvophilic monomer M₂, suitably as defined herein, wherein M₁ has a logP value greater than 1.5 (suitably greater than 3, more suitably greaterthan 4) and M₂ has a logP value less than 1 .5 (suitably less than 1 , more suitably less than 0).

D22. The foamable personal care composition (or hand-sanitizing composition) of D19 to D21 , wherein M₁ comprises pendent groups (RT) comprising a continuous carbon chain comprising at least 3 carbon atoms, one or more branched hydrocarbyl moieties, and at least one methyl (CH₃) group; whereas M₂ comprises pendent groups (R₂) having a chain length of at least 3, suitably at least 5, suitably at least 7, comprising two or more hetero atoms, that are free of any methyl groups, with the optional exception of a single terminal methyl group attached to a heteroatom.

D23. The foamable personal care composition (or hand-sanitizing composition) of D19 to D22, wherein M₁ comprises pendent groups (RT) comprising a continuous carbon chain comprising at least 5 carbon atoms and at least two methyl (CH₃) groups; whereas M₂ comprises pendent groups (R₂) comprising at least one polyether or polyester moiety, preferably at least one polyoxyalkylene (preferably polyoxyethylene) moiety comprising at least two oxyalkylene (preferably oxyethylene) monomeric units.

D24. The foamable personal care composition (or hand-sanitizing composition) of D19 to D23, wherein the copolymer compound has a homogeneous polyacrylic backbone or a homogeneous polyalkylacrylic backbone.

D25. The foamable personal care composition (or hand-sanitizing composition) of D24, wherein the copolymer compound has a polyacrylic backbone.

D26. The foamable personal care composition (or hand-sanitizing composition) of D19 to D25, wherein M₁ is selected from the group consisting of TMHA, TMHMA, EHA, iOA, and M₂ is selected from the group consisting of PEGA, AA, PEGMA, MAA, and GMA.

D27. The foamable personal care composition (or hand-sanitizing composition) of D26, wherein M₁ is TMHA and M₂ is PEGA. D28. The foamable personal care composition (or hand-sanitizing composition) of D27, wherein the copolymer compound has the Formula poly(PEGA-stat-TMHA).

D29. The foamable personal care composition (or hand-sanitizing composition) of D28, wherein the weight ratio of PEGA:TMHA is between 2:1 and 1 :2.

D30. The foamable personal care composition (or hand-sanitizing composition) of D1 to D29, wherein the composition is free of silicon and/or fluorine-containing surfactants.

D31 . The foamable personal care composition (or hand-sanitizing composition) of D1 to D30, wherein the composition is free of silicon and/or fluorine-containing compounds.

D32. The foamable personal care composition (or hand-sanitizing composition) of D1 to D31 , wherein the composition leaves no greasy-feeling residues following dispensation.

D33. The foamable personal care composition (or hand-sanitizing composition) of D1 to D32, wherein the composition further comprises an emollient, suitably 0.1-2 wt% emollient.

D34. The foamable personal care composition (or hand-sanitizing composition) of D33, wherein the emollient is or comprises glycerol, and suitably the composition comprises 0.4-1.6 wt% glycerol.

D35. The foamable personal care composition (or hand-sanitizing composition) of D1 to D34, wherein the composition further comprises a sporicide, suitably about 0.0003-0.03 wt% sporicide.

D36. The foamable personal care composition (or hand-sanitizing composition) of D35, wherein the sporicide is an oxidising agent, suitably hydrogen peroxide, so suitably the composition comprises 0.0015-0.006 wt% hydrogen peroxide (or 0.05-0.2 wt% of 3% hydrogen peroxide solution).

D37. The foamable personal care composition (or hand-sanitizing composition) of D1 to D36, wherein the composition further comprises an additional antisceptic agent.

D38. The foamable personal care composition (or hand-sanitizing composition) of D37, wherein the antisceptic agent is a quaternary ammonium compound or chlorhexidine.

D39. The foamable personal care composition (or hand-sanitizing composition) of D1 to D38, wherein the composition further comprises an additional foaming agent.

D40. The foamable personal care composition (or hand-sanitizing composition) of D39, wherein the composition further comprises a fragrance D1 to D39.

D41 . The foamable personal care composition (or hand-sanitizing composition) of D1 to D40, wherein the composition further comprises a colourant.

[00194] In a particular embodiment, the foamable personal care composition (or hand-sanitizing composition) composition comprises 0.5 and 5 wt% copolymer compound and 80 to 99 wt% alcoholic solvent system, wherein the alcoholic solvent system comprise water and the alcohol (e g. ethanol) in a weight ratio of between 3:7 and 1 :1. In a particular embodiment, the foamable personal care composition (or hand-sanitizing composition) composition comprises 0.5 and 5 wt% copolymer compound and 80 to 99 wt% alcoholic solvent system, wherein the alcoholic solvent system comprise water and the alcohol (e.g. ethanol) in a weight ratio of between 1 :9 and 1 :1.

[00195] In a particular embodiment, the foamable personal care composition (or hand-sanitizing composition) composition comprises 0.5 and 5 wt% copolymer compound and 80 to 99 wt% alcoholic solvent system, wherein the alcoholic solvent system comprise water and the alcohol (e g. ethanol) in a weight ratio of between 3:7 and 1 :1 ; wherein the copolymer compound is poly(M₁-stat-M₂), wherein the weight ratio of M₁ to M₂ in the copolymer compound is between 3:1 and 1 :3, wherein M₁ comprises pendent groups (RT) comprising a continuous carbon chain comprising at least 5 carbon atoms and at least two methyl (CH₃) groups; whereas M₂ comprises pendent groups (R₂) comprising at least one polyether or polyester moiety, preferably at least one polyoxyalkylene (preferably polyoxyethylene) moiety comprising at least two oxyalkylene (preferably oxyethylene) monomeric units.

[00196] In a particular embodiment, the foamable personal care composition (or hand-sanitizing composition) composition comprises 0.5 and 5 wt% copolymer compound and 80 to 99 wt% alcoholic solvent system, wherein the alcoholic solvent system comprise water and the alcohol (e g. ethanol) in a weight ratio of between 3:7 and 1 :1 ; wherein the copolymer compound has the Formula poly(PEGA-stat-TMHA), wherein the weight ratio of PEGA:TMHA is 2:1 between 2:1 and 1 :2. [00197] Whilst the foamed personal care composition (or foamed hand-sanitizing composition) may be defined by any of the features or embodiments disclosed herein in relation to a foamed composition, including those of numbered paragraphs C1 to C14 (in relation to which the foamed composition may be defined), or defined by any of the features or embodiments disclosed herein in relation to the foamable person care composition (or foamable hand-sanitizing composition), including those of numbered paragraphs D1 to D41 , the following numbered paragraphs E1 to E11 disclose specific embodiments of the foamed personal care composition (or foamed hand-sanitizing composition):

E1 . A foamed personal care composition (or foamed hand-sanitizing composition) comprising the foamable personal care composition (or foamable hand-sanitizing composition) and bubbles.

E2. The foamed personal care composition (or foamed hand-sanitizing composition) of E1 , wherein the bubbles are gas bubbles, suitably air bubbles.

E3. The foamed personal care composition (or foamed hand-sanitizing composition) of E2, wherein the (gas) air bubbles are introduced to the foamable personal care composition (or foamable hand-sanitizing composition) during dispensation, suitably via a specially-adapted nozzle.

E4. The foamed personal care composition (or foamed hand-sanitizing composition) of E1 to E3, wherein the foamable personal care composition (or foamable hand-sanitizing composition) is transformed into the foamed personal care composition (or foamed hand-sanitizing composition) by pumping air through the foamable personal care composition (or foamable hand-sanitizing composition) during dispensation, suitably through a aerating nozzle.

E5. The foamed personal care composition (or foamed hand-sanitizing composition) of E1 to E4, wherein the composition comprises a mixture of liquid (or unfoamed) foamable personal care composition (or foamable handsanitizing composition) and foam, suitably wherein the foam floats on top of the liquid.

E6. The foamed personal care composition (or foamed hand-sanitizing composition) of E1 to E5, wherein at least 50% of the foam, by volume, persists for at least 2 seconds, suitably for at least 5 seconds, suitably for at least 10 seconds - NB. this can be measured by observing the behaviour over time of the foam in a cylindrical vessel of constant diameter (such as a measuring cylinder).

E7. The foamed personal care composition (or foamed hand-sanitizing composition) of E6, wherein at least 50% of the foam, by volume, persists for at least 20 seconds, suitably for at least 30 seconds. In an embodiment, at least 50% of the foam, by volume, persists for at least 100 seconds. In an embodiment, at least 50% of the foam, by volume, persists for at least 300 seconds.

E8. The foamed personal care composition (or foamed hand-sanitizing composition) of E1 to E7, wherein the composition exhibits a foam ratio (suitably at time = 0, when the foam is dispensed) between 0.1 and 100 - NB. a foam ratio is a volumetric ratio between the foam and liquid (where the foam typically floats on top of the liquid), for instance as observed when said foamed composition (and any residual unfoamed, foamable composition) is placed in or dispensed into a measuring cylinder of constant diameter, where the relevant foam ratio would be measurable as the height of the foam divided by the height of the liquid.

E9. The foamed personal care composition (or foamed hand-sanitizing composition) of E8, wherein the composition exhibits a foam ratio between 0.2 and 10.

E10. The foamed personal care composition (or foamed hand-sanitizing composition) of E9, wherein the composition exhibits a foam ratio between 0.3 and 2.

E11 . The foamed personal care composition (or foamed hand-sanitizing composition) of E10, wherein the composition exhibits a foam ratio between 0.4 and 1.8.

[00198] The embodiments and features disclosed in this section may be combined with any of embodiments A1 to A28, B1 to B13, and/or C1 to C14. The embodiments and features disclosed in this section may preferably be combined with any embodiments and features disclosed in any other section herein.

[00199] According to a further aspect of the present invention, there is provided a firefighting concentrate composition, suitably as defined herein. The firefighting concentrate suitably comprises a copolymer compound as defined herein, suitably instead of or in addition to one or more other surfactants. The firefighting concentration may suitably further comprise further firefighting composition ingredients. Firefighting concentrates are well known in the art, for instance in US4060489A, US20020030176A1 , US5207932A and documents referenced therein. The copolymer compound of the invention is thought to provide foam stabilisation, especially in the presence of hydrophobic solvents which may be the target of firefighting efforts. The copolymer compound may also aid formation of a solid barrier upon fuel, especially where the relevant firefighting composition comprise a precipitating or gelling polymer, such as a polysaccharide.

[00200] According to a further aspect of the present invention, there is provided a foamable firefighting composition. The foamable firefighting composition is suitably formed by mixing the aforesaid firefighting concentrate with a solvent system (suitably water). The aforementioned foamable composition may be a foamable firefighting composition.

[00201] According to a further aspect of the present invention there is provided a (foamed or foamable) firefighting composition dispenser (or a fire-extinguisher), comprising a reservoir, a dispensing nozzle, and a fluid connection (or conduit) between the reservoir and the dispensing nozzle. The reservoir may contain a foamed firefighting composition (i.e. pre-foamed) or a foamable firefighting composition (i.e. a composition that will be transformed into a foam). Fire- extinguishers or fire-hoses may dispense either “aspirated” (or primary aspirated) foam or “non-aspirated” (or secondary aspirated) foam, depending on the circumstances. The former means the dispenser contains a pre-foamed mix (i.e. foamed composition rather than foamable composition) whereas the latter means the dispenser contains an unfoamed but foamable composition. The dispensing nozzle is suitably operable or configured (manually or automatically, optionally in response to a detection signal) to dispense the (foamed or foamable) firefighting composition from the reservoir and out through the dispensing nozzle. The foamable firefighting composition may become a foamed firefighting composition before or as it exits the nozzle or en route to the nozzle. The dispensing nozzle may be manually actuated, for instance by releasing or opening a valve, suitably so that the foamable firefighting composition is dispensed out of the dispensing nozzle, suitably under pressure (suitably under pressure by a pressurized reservoir).

[00202] Foamable firefighting compositions are generally formed by mixing a firefighting concentrate with a solvent system (generally water) to form the foamable firefighting composition, suitably in appropriate proportions that provide sufficient foam production and good firefighting performance. Such proportions are generally between 0.1 and 10 wt firefighting concentrate in the foamable firefighting composition, though manufacturers generally provide (foamed or foamable) firefighting compositions with either 1 wt%, 3 wt%, or 6 wt% firefighting concentrate in water. This foamable firefighting composition is, in general, a premixture that will then be transformed into a foamed firefighting composition, suitably by aspirating the premixture, suitably by adding a (bubble-forming) gas (such as air). Such aspirating may comprise primary aspiration (e g. aspiration prior to a foamed composition leaving, or potentially even reaching, the nozzle) or secondary aspiration (e g. aspiration during or after the foamable composition leaves the nozzle). However, since the foamed composition is essentially the same composition as the foamable composition, except for the aspirating gas, the foamed composition may in some embodiments be considered the same as the foamable composition.

[00203] Whilst the firefighting concentrate composition may be defined by any of the features or embodiments disclosed herein in relation to a foamable composition (albeit suitably without or with a reduced amount ofthe solvent system), including those of numbered paragraphs C1 to C14, the following numbered paragraphs F1 to F73 disclose specific embodiments of the firefighting concentrate composition:

F1 . A firefighting concentrate composition comprising a copolymer compound.

F2. The firefighting concentrate composition of F1 , wherein the concentrate composition is for forming a foamable firefighting composition or a foamed firefighting composition as defined herein.

F3. The firefighting concentrate composition of F1 to F2, wherein the concentrate composition further comprises one or more ingredients selected from the group consisting of: a solvent system (e g. comprising an organic solvent and/or water), a film-forming agent (e.g. one or more fluorinated and/or silicon surfactants), a water-soluble polymer that precipitates or forms a gel upon contact with a water-miscible flammable organic solvent (e g. polysaccharide), an anti-freeze agent, a corrosion inhibitor, an inorganic compound, a chelating agent, a buffering agent, a fuel emulsifier, and a combination of any two or more of the aforesaid.

F4. The firefighting concentrate composition of F1 to F3, wherein the copolymer compound is defined according to any of A1 to A28 and/or any of B1 to B13. F5. The firefighting concentrate composition of F1 to F4, wherein the copolymer compound is defined by Formula la: poly(M₁-co-M₂) or by Formula Ila: poly(M₁-stat-M₂), wherein the weight ratio of M₁ to M₂ in the copolymer compound is between 4:1 and 1 :4, preferably between 3:1 and 1 :3, most preferably between 2:1 and 1 :2.

F6. The firefighting concentrate composition of F4 to F5, wherein M₁ has a logP value greaterthan 1 .5 (suitably greater than 3, more suitably greater than 4) and M₂ has a logP value less than 1.5 (suitably less than 1 , more suitably less than 0).

F7. The firefighting concentrate composition of F4 to F6, wherein at least 1000 parts by mass of water are required to dissolve 1 part by mass of M₁ and at most 10 parts by mass of water are required to dissolve 1 part by mass of M₂.

F8. The firefighting concentrate composition of F4 to F6, wherein M₁ comprises pendent groups (RT) comprising a continuous carbon chain comprising at least 3 carbon atoms, and at least one methyl (CH₃) group or perfluoromethyl (CF₃) group; whereas M₂ comprises pendent groups (R₂) that are either H or a group that is free of any methyl groups (or perfluoromethyl groups) (with the optional exception of a methyl or perfluoromethyl group attached to a heteroatom; or with the optional exception of a terminal methyl or perfluoromethyl group, suitably attached to a heteroatom, such as may be the case for PEGA or PEGMA, especially where there is only a single such terminal methyl), free of any continuous carbon chains comprising 3 or more carbon atoms, and comprises one or more heteroatoms (preferably one or more oxygen atoms).

F9. The firefighting concentrate composition of F4 to F8, wherein M₁ comprises pendent groups (RT) comprising a continuous carbon chain comprising at least 3 carbon atoms and either at least two methyl (CH₃) groups, suitably attached to a silicon atom, or at least one perfluoromethyl group; whereas M₂ comprises pendent groups (R₂) that are hydrogen.

F10. The firefighting concentrate composition of F4 to F9, wherein M₁ comprises pendent groups (RT) comprising a continuous carbon chain comprising at least 3 carbon atoms and either at least two methyl (CH₃) groups, suitably attached to a silicon atom, or at least one perfluoromethyl group; whereas M₂ comprises pendent groups (R₂) comprising at least one polyether or polyester moiety, preferably at least one polyoxyalkylene (preferably polyoxyethylene) moiety comprising at least two oxyalkylene (preferably oxyethylene) monomeric units.

F11. The firefighting concentrate composition of F4 to F10, wherein RT of the copolymer compound comprises a (perfluorocarbon group that is part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide, suitably wherein the copolymer compound is otherwise free of fluorine atoms.

F12. The firefighting concentrate composition of F4 to F11 , wherein M₁ of the copolymer compound comprises a (per)fluorocarbon ester wherein the alcohol portion of the ester comprises or consists of a (per)fluorocait>on group whilst the carboxylic acid portion of the ester is free of any fluorine atoms.

F13. The firefighting concentrate composition of F4 to F12, wherein RT of the copolymer compound comprises a siloxane (suitably methyl siloxane moiety or perfluoromethyl siloxane moiety) group that is part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide, suitably wherein the copolymer compound is otherwise free of silicon atoms.

F14. The firefighting concentrate composition of F4 to F13, wherein M₁ of the copolymer compound comprises an ester whose alcohol portion of the ester comprises or consists of a siloxane group whilst the carboxylic acid portion of the ester is free of any silicon atoms.

F15. The firefighting concentrate composition of F4 to F14, wherein the copolymer compound has a homogeneous polyacrylic backbone or a homogeneous polyalkylacrylic backbone. The copolymer compound may have a polyacrylamide backbone, suitably a polyacrylamide backbone.

F16. The firefighting concentrate composition of F4 to F15, wherein the copolymer compound has a homogeneous polymethacrylic backbone.

F17. The firefighting concentrate composition of F4 to F16, wherein M₁ is selected from the group consisting of TMHA, TMHMA, EHA, iOA, TMSMA, and HFBMA, and M₂ is selected from the group consisting of PEGA, AA, PEGMA, MAA, and GMA. In a particular embodiment, M₁ is TMHMA and M₂ is GMA. F18. The firefighting concentrate composition of F17, wherein M₁ is selected from the group consisting of TMSMA and HFBMA, and M₂ is selected from the group consisting of PEGA, AA, PEGMA, MAA, and GMA.

F19. The firefighting concentrate composition of F18, wherein M₁ is selected from the group consisting of TMSMA and HFBMA, and M₂ is selected from the group consisting PEGMA and MAA.

F20. The firefighting concentrate composition of F19, wherein M₁ is TMSMA and M₂ is PEGMA.

F21 . The firefighting concentrate composition of F19, wherein M₁ is TMSMA and M₂ is MAA.

F22. The firefighting concentrate composition of F19, wherein M₁ is HFBMA and M₂ is PEGMA.

F23. The firefighting concentrate composition of F19, wherein M₁ is HFBMA and M₂ is MAA.

F24. The firefighting concentrate composition of F19, wherein the copolymer compound has the formula poly(PEGMA- stat-TMSMA), suitably in a weight ratio of PEGMA:TMSMA between 4:1 and 1 :4, suitably between 3:2 and 2:3.

F25. The firefighting concentrate composition of F19, wherein the copolymer compound has the formula poly(MAA- stat-TMSMA), suitably in a weight ratio of PEGMA:TMSMA between 4:1 and 1 :4, suitably between 3:2 and 2:3.

F26. The firefighting concentrate composition of F19, wherein the copolymer compound has the formula poly(PEGMA- stat-HFBMA), suitably in a weight ratio of PEGMA: HFBMA between 4:1 and 1 :4, suitably between 3:2 and 2:3.

F27. The firefighting concentrate composition of F19, wherein the copolymer compound has the formula poly(MAA- stat- HFBMA), suitably in a weight ratio of PEGMA: HFBMA between 4:1 and 1 :4, suitably between 3:2 and 2:3.

F28. The firefighting concentrate composition of F1 to F27, wherein the copolymer compound is free of silicon and/or fluorine atoms.

F29. The firefighting concentrate composition of F1 to F28, wherein the copolymer compound is present within the concentrate composition at a concentration of between 0.1 and 30 wt%.

F30. The firefighting concentrate composition of F29, wherein the copolymer compound is present within the concentrate composition at a concentration of between 1 and 15 wt%.

F31. The firefighting concentrate composition of F30, wherein the copolymer compound is present within the concentrate composition at a concentration of between 2 and 10 wt%, most preferably between 1 and 5 wt%.

F32. The firefighting concentrate composition of F1 to F31 , further comprising a film-forming agent.

F33. The firefighting concentrate composition of F32, wherein the film-forming agent is present within the concentrate composition at a concentration of between 0.1 and 15 wt%, most preferably between 1 and 6 wt%.

F34. The firefighting concentrate composition of F32 to F33, wherein the film-forming agent consists of or comprises the copolymer compound.

F35. The firefighting concentrate composition of F32 to F34, wherein the film-forming agent consists of or comprises a fluorinated surfactant, a fluorocarbon surfactant, and/or a silicone surfactant.

F36. The firefighting concentrate composition of F1 to F35, wherein the concentrate composition comprises at most 5 wt% fluorinated surfactants, more suitably at most 2 wt%, preferably at most 1 wt%, most preferably at most 0.1 wt%, wherein suitably said fluorinated surfactants are otherthan as defined in relation to the copolymer compound (e g. a fluorinated surfactant with perfluorocarbon groups within the carboxylic acid part of said surfactant).

F37. The firefighting concentrate composition of F1 to F36, wherein the concentrate composition comprises at most 5 wt% perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), and/or any fluorotelomers, more suitably at most 2 wt%, preferably at most 1 wt%, most preferably at most 0.1 wt%.

F38. The firefighting concentrate composition of F1 to F37, wherein the concentrate composition comprises at most 5 wt% silicone surfactants, more suitably at most 2 wt%, preferably at most 1 wt%, most preferably at most 0.1 wt%, wherein suitably said silicone surfactants are otherthan as defined in relation to the copolymer compound (e g. a polysiloxane substituted with hydrophilic groups, such as polyoxyethylene groups)..

F39. The firefighting concentrate composition of F1 to F38, wherein the concentrate composition comprises at most 5 wt% fluorinated and silicone surfactant combined, more suitably at most 2 wt%, preferably at most 1 wt%, most preferably at most 0.1 wt%.

F40. The firefighting concentrate composition of F1 to F39, wherein the concentrate composition is (substantially) free of any fluorinated surfactants. F41 . The firefighting concentrate composition of F1 to F40, wherein the concentrate composition is (substantially) free of perfluorooctanoic acid (PFOA), perfluorooctanesulfonic acid (PFOS), and any fluorotelomers.

F42. The firefighting concentrate composition of F1 to F41 , wherein the concentrate composition is (substantially) free of any silicone surfactant.

F43. The firefighting concentrate composition of F1 to F42, wherein the concentrate composition is (substantially) free of any fluorinated and silicone surfactant.

F44. The firefighting concentrate composition of F1 to F43, further comprising a foaming agent.

F45. The firefighting concentrate composition of F44, wherein the foaming agent is present within the concentrate composition at a concentration of between 0.1 and 12 wt%.

F46. The firefighting concentrate composition of F44 to F45, wherein the foaming agent is or comprises one or more surfactants (anionic, cationic, or non-ionic) other than the copolymer compound.

F47. The firefighting concentrate composition of F46, wherein the foaming agent is or comprises sodium decyl sulphate.

F48. The firefighting concentrate composition of F1 to F47, further comprising a foam stabiliser.

F49. The firefighting concentrate composition of F48, wherein the foam stabiliser is present within the concentrate composition at a concentration between 0.1 and 15 wt%.

F50. The firefighting concentrate composition of F48 to F49, wherein the foam stabiliser is or comprises the copolymer compound.

F51 . The firefighting concentrate composition of F48 to F50, wherein the foam stabiliser is or comprises lauryl alcohol.

F52. The firefighting concentrate composition of F1 to F51 , further comprising a corrosion inhibitor.

F53. The firefighting concentrate composition of F52, wherein the corrosion inhibitor is present within the concentrate composition at a concentration between 0.01 and 3 wt%, more suitably between 0.1 and 2 wt%.

F54. The firefighting concentrate composition of F1 to F53, further comprising an inorganic compound.

F55. The firefighting concentrate composition of F54, wherein the inorganic compound is present within the concentrate composition at a concentration between 0.01 and 3 wt%, more suitably between 0.1 and 2 wt%.

F56. The firefighting concentrate composition of F54 to F55, wherein the inorganic compound is or comprises magnesium sulphate.

F57. The firefighting concentrate composition of F1 to F56, further comprising a chelating (or sequestering) agent.

F58. The firefighting concentrate composition of F57, wherein the chelating agent is present within the concentrate composition at a concentration between 0.001 and 2 wt%, more suitably between 0.1 and 2 wt%.

F59. The firefighting concentrate composition of F1 to F58, further comprising a buffering agent.

F60. The firefighting concentrate composition of F59, wherein the buffering agent is present within the concentrate composition at a concentration between 0.01 and 3 wt%, more suitably between 0.1 and 2 wt%.

F61 . The firefighting concentrate composition of F1 to F60, further comprising one or more preservatives, suitably that preserve against the propagation of bacteria and/or fungi moulds.

F62. The firefighting concentrate composition of F61 , wherein the one or more preservatives are present within the concentrate at a concentration between 0.001 and 2 wt%, more suitably between 0.1 and 1 wt%

F63. The firefighting concentrate composition of F1 to F62, further comprising one or more antifreeze agents.

F64. The firefighting concentrate composition of F63, wherein the one or more antifreeze agents are selected from the group consisting of a glycol ether, ethylene glycol, glycerine, propylene glycol, butyl carbitol, trimethyl-trimethylene glycol, hexylene glycol, and any combination thereof.

F65. The firefighting concentrate composition of F63 to F64, wherein the one or more antifreeze agents are present within the concentrate at a concentration between 0.1 and 20 wt%, more suitably between 1 and 10 wt%.

F66. The firefighting concentrate composition of F1 to F65, further comprising one or more solvents, suitably to reduce viscosity and enhance foaming.

F67. The firefighting concentrate composition of F66, wherein the one or more solvents comprise an organic solvent and/or optionally water. F68. The firefighting concentrate composition of F67, wherein the one or more solvents comprise an organic solvent.

F69. The firefighting concentrate composition of F68, wherein the organic solvent is selected from the group consisting of glycol, a glycol, a glycol ether, an alkylene glycol, ethylene glycol, propylene glycol, trimethyl-trimethylene glycol hexylene glycol, glycerine, a glyceryl ether, butyl carbitol, N-methyl-pyrrolidone, 2-(2-butoxyethoxy)ethanol, diethylene glycol butyl ether, and any combination thereof. In a particular embodiment, the organic solvent is diethylene glycol.

F70. The firefighting concentrate composition of F68 to F69, wherein the one or more solvents, most particularly the organic solvent(s), are present within the concentrate at a concentration between 3 and 70 wt%, more suitably between 4 and 50 wt%, most suitably between 5 and 40 wt%.

F71. The firefighting concentrate composition of F1 to F71 , wherein concentrate comprises 1 -90 wt% water, more suitably 2-50 wt%, most suitably 5-30 wt% water.

F72. The firefighting concentrate composition of F1 to F71 , wherein concentrate has a pH of pH 6-9, more suitably pH 6.5-8, most suitably pH 7-7.8.

F73. The firefighting concentrate composition of F1 to F72, wherein the firefighting concentrate is a hazmat foam concentrate.

[00204] In a particular embodiment, the firefighting concentrate composition comprises 0.1 and 30 wt% copolymer compound of Formula Ila: poly(M₁-stat-M₂), wherein M₁ is (or in the context of the polymer is derived from) a solvophobic monomer and M₂ is a solvophilic monomer; wherein the weight ratio of M₁ to M₂ in the copolymer compound is between 3:1 and 1 :3, most preferably between 2:1 and 1 :2; wherein M₁ comprises pendent groups (RT) comprising a continuous carbon chain comprising at least 3 carbon atoms, and at least one methyl (CH₃) group or perfluoromethyl (CF₃) group; whereas M₂ comprises pendent groups (R₂) that are either H or a group that is free of any methyl groups (or perfluoromethyl groups), with the optional exception of a single terminal methyl group attached to a heteroatom, free of any continuous carbon chains comprising 3 or more carbon atoms, and comprises one or more heteroatoms (preferably one or more oxygen atoms).

[00205] In a particular embodiment, the firefighting concentrate composition comprises 1 and 15 wt% copolymer compound of Formula Ila: poly(M₁-stat-M₂), wherein M₁ is (or in the context of the polymer is derived from) a solvophobic monomer and M₂ is a solvophilic monomer; wherein the weight ratio of M₁ to M₂ in the copolymer compound is between 3:1 and 1 :3, most preferably between 2:1 and 1 :2; wherein M₁ comprises pendent groups (RT) comprising a (perfluorocarbon group that is part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide, suitably wherein the copolymer compound is otherwise free of fluorine atoms; whereas M₂ comprises pendent groups (R₂) that are either H or a group that is free of any methyl groups (or perfluoromethyl groups), with the optional exception of a single terminal methyl group attached to a heteroatom, free of any continuous carbon chains comprising 3 or more carbon atoms, and comprises one or more heteroatoms (preferably one or more oxygen atoms).

[00206] In a particular embodiment, the firefighting concentrate composition comprises 1 and 15 wt% copolymer compound of Formula Ila: poly(M₁-stat-M₂), wherein M₁ is (or in the context of the polymer is derived from) a solvophobic monomer and M₂ is a solvophilic monomer; wherein the weight ratio of M₁ to M₂ in the copolymer compound is between 3:1 and 1 :3, most preferably between 2:1 and 1 :2; wherein M₁ comprises pendent groups (RT) comprising a siloxane (suitably methyl siloxane moiety or perfluoromethyl siloxane moiety) group that is part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide, suitably wherein the copolymer compound is otherwise free of silicon atoms; whereas M₂ comprises pendent groups (R₂) that are either H or a group that is free of any methyl groups (or perfluoromethyl groups) , with the optional exception of a single terminal methyl group attached to a heteroatom, free of any continuous carbon chains comprising 3 or more carbon atoms, and comprises one or more heteroatoms (preferably one or more oxygen atoms).

[00207] In a particular embodiment, the firefighting concentrate composition is as defined in any one of the preceding particular embodiments, wherein the firefighting concentrate composition further comprises a corrosion inhibitor, suitably at a concentration of 0.01 and 3 wt%, and an organic solvent, suitably an organic solvent selected from the group consisting of glycol, a glycol, a glycol ether, an alkylene glycol, ethylene glycol, propylene glycol, trimethyl-trimethylene glycol hexylene glycol, glycerine, a glyceryl ether, butyl carbitol, N-methyl-pyrrolidone, and any combination thereof. In a particular embodiment, the organic solvent is diethylene glycol. [00208] Whilst the foamable firefighting composition may be defined by any of the features or embodiments disclosed herein in relation to a foamable composition, including those of numbered paragraphs C1 to C14, the following numbered paragraphs G1 to G37 disclose specific embodiments of the foamable firefighting composition:

G1 . A foamable firefighting composition comprising a copolymer compound, as defined herein, and a solvent system.

G2. A foamable firefighting composition comprising a copolymer compound, a solvent system, and any other relevant ingredients defined in relation to the firefighting concentrate composition, suitably as defined herein in relation to the firefighting concentrate composition as defined in any of F1 to F73, suitably in relevant concentrations determinable by reference to the concentration of the firefighting concentrate composition within the foamable firefighting composition (e g. taking account of dilution factors, for instance, by reference to relative amounts of the solvent system and the concentrate).

G3. A foamable firefighting composition obtained by (or directly obtained by) mixing a firefighting concentrate composition, as defined herein, suitably as defined in any of F1 to F73, with a solvent system.

G4. A foamable firefighting composition comprising a firefighting concentrate composition and a solvent system, wherein the firefighting concentrate composition is suitably as defined herein, suitably as defined herein in relation to the firefighting concentrate composition as defined in any of F1 to F73.

G5. The foamable firefighting composition of G1 to G4, wherein the composition comprises or consists of, or is obtained by mixing together, 0.1 -20 wt% firefighting concentrate composition and 80 to 99.9 wt% solvent system.

G6. The foamable firefighting composition of G1 to G4, wherein the composition comprises or consists of, or is obtained by mixing together, 0.1 -20 vol% firefighting concentrate composition and 80 to 99.9 vol% solvent system.

G7. The foamable firefighting composition of G1 to G4, wherein the composition comprises or consists of, or is obtained by mixing together, 0.5-10 wt% firefighting concentrate composition and 90 to 99.5 wt% solvent system.

G8. The foamable firefighting composition of G1 to G4, wherein the composition comprises or consists of, or is obtained by mixing together, 0.5-10 vol% firefighting concentrate composition and 90 to 99.5 vol% solvent system.

G9. The foamable firefighting composition of G1 to G4, wherein the composition comprises or consists of, or is obtained by mixing together, 0.5-1 .5 wt% firefighting concentrate composition and 98.5 to 99.5 wt% solvent system.

G10. The foamable firefighting composition of G1 to G4, wherein the composition comprises or consists of, or is obtained by mixing together, 0.5-1.5 vol% firefighting concentrate composition and 98.5 to 99.5 vol% solvent system.

G11. The foamable firefighting composition of G1 to G4, wherein the composition comprises or consists of, or is obtained by mixing together, 2.5-3.5 wt% firefighting concentrate composition and 96.5 to 97.5 wt% solvent system.

G12. The foamable firefighting composition of G1 to G4, wherein the composition comprises or consists of, or is obtained by mixing together, 2.5-3.5 vol% firefighting concentrate composition and 96.5 to 97.5 vol% solvent system.

G13. The foamable firefighting composition of G1 to G4, wherein the composition comprises or consists of, or is obtained by mixing together, 5.5-6.5 wt% firefighting concentrate composition and 93.5 to 94.5 wt% solvent system.

G14. The foamable firefighting composition of G1 to G4, wherein the composition comprises or consists of, or is obtained by mixing together, 5.5-6.5 vol% firefighting concentrate composition and 93.5 to 94.5 vol% solvent system.

G15. The foamable firefighting composition of G1 to G4, wherein the composition comprises or consists of, or is obtained by mixing together, 0.5 to 15 parts by weight firefighting concentrate composition and 85 to 99.5 parts by weight solvent system.

G16. The foamable firefighting composition of G1 to G4, wherein the composition comprises or consists of, or is obtained by mixing together, 0.5 to 15 parts by volume firefighting concentrate composition and 85 to 99.5 parts by volume solvent system. G17. The foamable firefighting composition of G1 to G4, wherein the composition comprises or consists of, or is obtained by mixing together, about 1 part by weight firefighting concentrate composition and about 99 parts by weight solvent system.

G18. The foamable firefighting composition of G1 to G4, wherein the composition comprises or consists of, or is obtained by mixing together, about 1 part by volume firefighting concentrate composition and about 99 parts by volume solvent system.

G19. The foamable firefighting composition of G1 to G4, wherein the composition comprises or consists of, or is obtained by mixing together, about 3 parts by weight firefighting concentrate composition and about 97 parts by weight solvent system.

G20. The foamable firefighting composition of G1 to G4, wherein the composition comprises or consists of, or is obtained by mixing together, about 3 parts by volume firefighting concentrate composition and about 97 parts by volume solvent system.

G21. The foamable firefighting composition of G1 to G4, wherein the composition comprises or consists of, or is obtained by mixing together, about 6 parts by weight firefighting concentrate composition and about 94 parts by weight solvent system.

G22. The foamable firefighting composition of G1 to G4, wherein the composition comprises or consists of, or is obtained by mixing together, about 6 parts by volume firefighting concentrate composition and about 94 parts by volume solvent system.

G23. The foamable firefighting composition of G1 to G22, wherein the solvent system is or comprises water.

G24. The foamable firefighting composition of G23, wherein the solvent system is or comprises at least 70 wt% water, more suitably at least 80 wt% water, more suitably at least 90 wt% water, most suitably at least 95 wt% water.

G25. The foamable firefighting composition of G24, wherein the solvent system (substantially) is water.

G26. The foamable firefighting composition of G25, wherein the water of the solvent system is provided by a fire-engine or fire-hydrant.

G27. The foamable firefighting composition of G1 to G26, wherein the composition is protein-based.

G28. The foamable firefighting composition of G27, wherein the composition is a fluoroprotein (FP) firefighting composition.

G29. The foamable firefighting composition of G27, wherein the composition is a film-forming fluoroprotein (FFFP) firefighting composition.

G30. The foamable firefighting composition of G1 to G29, wherein the composition is an aqueous film-forming foam (AFFF) firefighting composition.

G31. The foamable firefighting composition of G30, wherein the composition is an alcohol-resistant aqueous filmforming foam (AFFF-AR) firefighting composition.

G32. The foamable firefighting composition of G31 , wherein the composition comprises a water soluble polymer (e g. a polysaccharide) that precipitates upon contact with a water miscible fuel (e g. alcohol).

G33. The foamable firefighting composition of G32, wherein the water soluble polymer (e g. polysaccharide) is present within the concentrate.

G34. The foamable firefighting composition of G32, wherein the water soluble polymer (e g. polysaccharide) is present within the solvent system.

G35. The foamable firefighting composition of G1 to G34, wherein the composition is a synthetic-based (SYNDET) firefighting composition.

G36. The foamable firefighting composition of G1 to G35, wherein the composition is for primary aspiration.

G37. The foamable firefighting composition of G1 to G35, wherein the composition is for secondary aspiration.

[00209] The foamable firefighting composition is suitable for forming a foamed firefighting composition. As such, features relating to the foamed firefighting composition may be inherited by the foamable firefighting composition. [00210] Whilst the foamed firefighting composition (or indeed methods of manufacturing of forming a foamed firefighting composition) may be defined by any of the features or embodiments disclosed herein in relation to a foamed composition, including a foamed composition defined by reference to its parent foamable composition as per numbered paragraphs C1 to C14, the following numbered paragraphs H1 to H21 disclose specific embodiments of the foamed firefighting composition (which may be extrapolated to methods of manufacturing, generating, or forming said foamed firefighting compositions):

H1. A foamed firefighting composition comprising (or formed by mixing together) a foamable firefighting composition and bubbles (i.e. foam bubbles).

H2. A foamed firefighting composition, comprising (or formed by mixing together) a foamable firefighting composition and a gas (wherein the gas suitably forms bubbles).

H3. A foamed firefighting composition, comprising (or formed by mixing together) a firefighting concentrate composition, a solvent system (suitably as defined in relation to the foamable firefighting composition, suitably in G1 to G37) and a gas (wherein the gas suitable forms bubbles).

H4. The foamed firefighting composition of H1 to H3, wherein the foamable firefighting composition is as defined in any of G1 to G37.

H5. The foamed firefighting composition of H1 to H4, wherein the bubbles are gas bubbles, suitably air bubbles.

H6. The foamed firefighting composition of H1 to H5, wherein the bubbles are formed by primary aspiration.

H7. The foamed firefighting composition of H6, wherein primary aspiration comprises actively causing foaming of a foamable firefighting composition.

H8. The foamed firefighting composition of H7, wherein actively causing foaming comprises channelling the foamable firefighting composition through a foam-making facility, or simultaneously channelling both a firefighting concentration composition and solvent system through said foam-making facility, wherein said foam-making facility is operable or configured to introduce gas (e g. air) into the relevant feedstocks.

H9. The foamed firefighting composition of H8, wherein the foam-making facility comprises a turbulator, suitably for causing turbulent flow of feedstocks passing therethrough.

H10. The foamed firefighting composition of H8 to H9, wherein the foam-making facility comprises a gas injector, suitably for bubbling gas (e g. air) through feedstocks passing therethrough.

H11 . The foamed firefighting composition of H8 to H10, wherein the foam-making facility comprises both the turbulator and the gas injector, suitably to mix the feedstocks with an aspirate (e g. gas, e g. air) and agitate so as to produce a substantially uniformly sized bubbles within the resulting foam.

H12. The foamed firefighting composition of H8 to H11 , wherein the foam-making facility comprises a foam-making branchpipe through which the relevant feedstocks pass, suitably en route to a dispensing nozzle.

H13. The foamed firefighting composition of H1 to H5, wherein the bubbles are formed by secondary aspiration.

H14. The foamed firefighting composition of H13, wherein secondary aspiration comprises passive foaming of a foamable firefighting composition.

H15. The foamed firefighting composition of H14, wherein passive foaming comprises foam formation during mixing of a firefighting concentration composition and water, suitably under turbulent flow.

H16. The foamed firefighting composition of H14 to H15, wherein passive foaming comprises foam formation as the foamable firefighting composition travels through air (e g. after leaving a relevant dispenser).

H17. The foamed firefighting composition of H14 to H16, wherein passive foaming comprises foam formation as the foamable firefighting composition contacts a target object.

H18. The foamed firefighting composition of H1 to H17, wherein the foam is a low-expansion (LX) foam, wherein suitably the volumetric ratio of the foam (i.e. foamed firefighting composition) to the foamable firefighting composition (or mixture of concentrate composition with solvent system) is less than or equal to 20:1 .

H19. The foamed firefighting composition of H1 to H17, wherein the foam is a medium-expansion (MX) foam, wherein suitably the volumetric ratio of the foam (i.e. foamed firefighting composition) to the foamable firefighting composition (or mixture of concentrate composition with solvent system) is greater than or equal to 20:1 and less than or equal to 200:1. H20. The foamed firefighting composition of H1 to H17, wherein the foam is a high-expansion (HX) foam, wherein suitably the volumetric ratio of the foam (i.e. foamed firefighting composition) to the foamable firefighting composition (or mixture of concentrate composition with solvent system) is greater than 200:1 (though generally less than or equal to 1000:1).

H21. The foamed firefighting composition of H1 to H20, wherein the foam forms a solid precipitate, suitably a polysaccharide precipitate, upon contact with water-miscible flammable liquids.

[00211] According to a further aspect of the present invention there is provided a (foamed or foamable) firefighting composition dispenser (or a fire-extinguisher). Such dispensers suitably comprise a reservoir, a dispensing nozzle, and a fluid connection (or conduit) between the reservoir and the dispensing nozzle. The reservoir may contain a foamed firefighting composition (i.e. pre-foamed), a foamable firefighting composition (i.e. a composition that will be transformed into a foam), or a firefighting concentrate composition (that requires mixing with a solvent system to furnish a foamable firefighting composition). The latter is often preferable from a volume-efficiency perspective, especially where a solvent system (water) supply is provided externally. Fire-extinguishers or fire-hoses may dispense either “aspirated” (or primary aspirated) foam or “non-aspirated” (or secondary aspirated) foam, depending on the circumstances. The former means the dispenser contains a pre-foamed mix (i.e. foamed composition rather than foamable composition) whereas the latter means the dispenser contains an unfoamed but foamable composition. The dispensing nozzle is suitably operable or configured (manually or automatically, optionally in response to a detection signal) to dispense the (foamed or foamable) firefighting composition out through the dispensing nozzle. The foamable firefighting composition may become a foamed firefighting composition before or as it exits the nozzle or en route to the nozzle. The dispensing nozzle may be manually actuated, for instance by releasing or opening a valve, suitably so that the foamable firefighting composition is dispensed out of the dispensing nozzle, suitably under pressure (suitably under pressure by a pressurized reservoir). The dispensing nozzle or other part of the dispenser may be specially adapted to promote foaming of the foamable firefighting composition as the latter is dispensed through the nozzle.

[00212] Whilst the firefighting composition dispenser may be defined by any of the features or embodiments disclosed herein in relation to a foamable or foamed composition dispenser, the following numbered paragraphs 11 to 117 disclose specific embodiments of the firefighting composition dispenser:

11. A firefighting composition dispenser comprising a firefighting composition pipe (be it for conveying a foamable, foamed, or concentrate composition) and a dispensing nozzle in fluid connection with the firefighting composition pipe, wherein the dispenser is operable or configured to convey a firefighting composition (be it for conveying a foamable, foamed, or concentrate composition) to and out of the dispensing nozzle from the firefighting composition pipe.

12. A firefighting composition dispenser, comprising a reservoir or reservoir inlet connectable to the reservoir for a firefighting composition (be it a foamable, foamed, or concentrate composition) and a dispensing nozzle fluidly connected, suitably via a firefighting composition pipe, to the reservoir or reservoir inlet.

13. The firefighting composition dispenser of 11 to I2, wherein the reservoir contains the firefighting composition (be it a foamable, foamed, or concentrate composition).

14. The firefighting composition dispenser of 11 to I3, wherein the dispenser dispenses either “aspirated” (or primary aspirated) foam or “non-aspirated” (or secondary aspirated) foam.

15. The firefighting composition dispenser of I4, wherein the dispenser dispenses “aspirated” (or primary aspirated) foam, wherein the foam is aspirated during (or en route to) dispensation.

16. The firefighting composition dispenser of I5, wherein the dispenser dispenses “aspirated” (or primary aspirated) foam, wherein aspirated foam is stored (e g. in the reservoir) prior to operation of the dispenser.

17. The firefighting composition dispenser of 11 to I3, wherein the dispenser dispenses “non-aspirated” (or secondary aspirated) foam - for instance, raw foamable firefighting composition is dispensed without being previously transformed into a foamed firefighting composition. Such non-aspirated foams (foamable firefighting composition) may nonetheless foam after or whilst exiting the nozzle, for instance, as it travels through the air (e g. due to turbulence produced by a flowing stream of foamable firefighting composition), or when it strikes an object (again due to turbulence). 18. The firefighting composition dispenser of 11 to I7, wherein the dispenser is operable to convey the firefighting composition to and out of the dispensing nozzle, suitably via pumping (or under pressure).

19. The firefighting composition dispenser of 11 to I8, wherein the dispensing nozzle is operable or configured (manually or automatically, optionally in response to a detection signal) to dispense the (foamed or foamable) firefighting composition from the dispensing nozzle.

110. The firefighting composition dispenser of 11 to I9, wherein the firefighting composition is a foamed firefighting composition as defined herein. Where a foamed firefighting composition is stored, for instance in a reservoir, prior to dispensation, the foamed firefighting composition may be stored under pressure (e g. compressed).

111. The firefighting composition dispenser of 11 to I9, wherein the firefighting composition is a foamable firefighting composition as defined herein.

112. The firefighting composition dispenser of 11 to I9, wherein the firefighting composition is a firefighting concentrate composition as defined herein, though suitably said firefighting concentrate is transformed into a foamable or foamed firefighting composition prior to exiting the nozzle.

113. The firefighting composition dispenser of 112, wherein the dispenser comprises a water pipe and a mixing chamber (or mixing point) into or through which the water pipe and firefighting composition pipe feed to mix the firefighting concentrate composition and water en route to the nozzle.

114. The firefighting composition dispenser of 112 to 113, wherein the dispenser comprises a second reservoir or second reservoir inlet connectable to a second reservoir, wherein the second reservoir comprises water, and wherein the dispenser further comprises a mixing chamber through which firefighting concentrate composition and water can be simultaneously conveyed en route to the nozzle.

115. The firefighting composition dispenser of 11 to 114, wherein the dispenser comprises a foam-making facility in line with the dispensing nozzle, though optionally parallel to other feed lines (e g. a foam-making branch), and through which foamable firefighting composition is conveyed en route to the dispensing nozzle, and within which foamable firefighting composition is transformed into foamed firefighting composition, suitably via aspiration (e g. primary aspiration).

116. The firefighting composition dispenser of 11 to 115, wherein the dispenser is a fire-extinguisher, such as a handheld fire-extinguisher.

117. The firefighting composition dispenser of 11 to 115, wherein dispenser comprises a fire-hose or fire-hose outlet, for instance, such as those used with a fire-engine. Suitably the dispenser is a part of or integrated with a larger infrastructure suppling pressurized water, which may be fed through a water pipe, and later caused to mix with a firefighting composition (e g. concentrate), for instance, to form a foamed or foamable firefighting composition in situ. As such, formation of the foamable or foamed firefighting composition may be performed upstream, suitably via upstream apparatus connected to the dispenser, or within the disperser.

[00213] Further features of the firefighting composition dispenser will be self-evident from relevant method features described in numbered paragraphs H1 to H21 relating to the foamed firefighting composition. Moreover, aspects of the invention related to a method of manufacturing a foamed composition and a method of generating a foam, especially firefighting foams, will likewise be self-evident and derivable from the features of numbered paragraphs H1 to H21 and 11 to 117.

[00214] According to an aspect of the present invention there is provided a polymeric foam (or solid foam), suitably as defined herein. Suitably, the aforementioned foamable composition is a polymeric foam (or solid foam). In a particular embodiment, the polymeric foam is a polyurethane foam. The polymeric foam suitably comprises foam cells (or bubbles). The polymeric foam suitably comprises a copolymer compound as defined herein. Suitably the copolymer compound is present at the internal surfaces of the foam cells (or bubbles) within the polymeric foam. Suitably said copolymer compound stabilises the foam, suitably during and/or after foam generation. [00215] Polymeric foams, especially polyurethane foams, can be produced with a wide range of properties and thus have a wide variety of applications. As such, various different aspects of the present invention provide:

• A solid material comprising or consisting of a polymeric foam.

• A cleaning product (e g. a sponge) comprising or consisting of a polymeric foam. In such aspects, the polymeric foam is suitably a flexible polyurethane foam.

• A furniture item (e g. an upholstered furniture, a cushion, a mattress, a seat, a headrest, an armrest, a roof liner) comprising or consisting of a polymeric foam. In such aspects, the polymeric foam is suitably a flexible polyurethane foam.

• A building material or decoration material (e g. ceiling material, wall material) comprising or consisting of a polymeric foam.

• An insulation material, such as a thermal insulation material, comprising or consisting of a polymeric foam.

• A space-filling material comprising or consisting of a polymeric foam.

• A spray foam comprising or consisting of a polymeric foam.

• A sealant comprising or consisting of a polymeric foam.

• An adhesive comprising or consisting of a polymeric foam.

• A wound dressing comprising a polymeric foam.

• A synthetic soil comprising a polymeric foam

[00216] A polymeric foam is suitably a cellular polymeric matrix. The polymeric foam suitably thus exhibits a cellular structure. The cellular polymeric matrix suitably comprises cells distributed within a polymeric matrix. The cells are suitably holes, suitably gas-containing holes or liquid-containing holes. The cells are suitably gas-containing holes, especially once the polymeric foam is substantially dried (e g. by heating and/or evacuation). The cells are suitably bubbles, suitably gas bubbles. As such, the polymeric foam suitably comprises bubbles distributed within a polymeric matrix. Suitably copolymer compound, as defined herein, is present at the internal surfaces of the cells (or bubbles).

[00217] The cells or bubbles may be interconnected (e g. open cell), suitably such that the polymeric foam is porous. The cells or bubbles may be fluidly connected to the exterior of the polymer foam. The polymer foam may suitably comprise cells or bubbles fluidly connected to the exterior of the polymer foam. In an embodiment, at least 50 wt% of the cells or bubbles (or at least 50 wt% of the total volume of all of the cells or bubbles within the polymeric foam) are fluidly connected with the exterior of the polymer foam, more suitably at least 70 wt%, more suitably at least 90 wt%. In an embodiment, the polymeric foam is an open-cell foam. In an embodiment, the polymeric foam has from 50 to 95 % open-cell content, suitably 60-95% open-cell content. Open cell foams tend to be softer and more flexible than corresponding closed cell foams.

[00218] The cells or bubbles may be (substantially) isolated from each other (e g. closed cell) - for instance, each cell or bubble may be entirely surrounded by polymeric matrix. The polymeric foam may comprise isolated cells or bubbles, or comprise cells or bubbles with no fluid connection with the exterior of the polymeric foam. In an embodiment, at least 50 wt% of the cells or bubbles (or at least 50 wt% of the total volume of all of the cells or bubbles within the polymeric foam) are isolated cells or bubbles (i.e. with no fluid connection with the exterior of the polymeric foam), more suitably at least 70 wt%, more suitably at least 90 wt%. In an embodiment, the polymeric foam is a closed-cell foam. Closed cell foams tend to be harder, more rigid, and more stable than corresponding open cell foams.

[00219] The polymeric matrix suitably comprises a matrix polymer (or matrix copolymer), and optionally one or more additives (e g. stabilisers, suitably to protect or preserve the matrix polymer, fire-retardants, catalysts).

[00220] The matrix polymer of the polymeric matrix may be any suitable matrix polymer (which includes any suitably matrix copolymer). The matrix polymer is suitably polyurethane or a polyurethane. The matrix polymer may be a form of synthetic rubber. [00221] The cellular structure within the polymeric foam reduces density. The polymeric foam is suitably a lightweight foam. The polymeric foam suitably has a density that is lower than the polymeric matrix perse. The polymeric foam suitably has a density that is lower than the matrix polymer per se.

[00222] The cellular structure of the polymeric foam may reduce stiffness. The polymeric foam is thus suitably flexible. The polymeric foam suitably has a flexibility (suitably longitudinal flexibility within the plane of the longest dimension) greater than the polymeric matrix per se. The polymeric foam suitably has a flexibility greater than the matrix polymer per se. The polymer foam may be compressible. The polymeric foam suitably has a compressibility greater than the polymeric matrix per se. The polymeric foam suitably has a compressibility greater than the matrix polymer per se. The polymer foam may be elastic (or stretchable). As such, the polymer foam may be an elastomer. The polymeric foam suitably has an elasticity greater than the polymeric matrix per se. The polymeric foam suitably has an elasticity greater than the matrix polymer per se.

[00223] Suitably, the polymeric foam is flexible, compressible, and elastic.

[00224] The cellular structure of the polymer foam may increase thermal insulation. The polymeric foam suitably has a greater thermal insulating capacity than the polymeric matrix per se. The polymeric foam suitably has a greater thermal insulating capacity than the matrix polymer per se.

[00225] The cellular structure of the polymer foam may increase acoustic insulation. The polymeric foam suitably has a greater acoustic insulating capacity than the polymeric matrix per se. The polymeric foam suitably has a greater acoustic insulating capacity than the matrix polymer perse.

[00226] The cellular structure also facilitates water retention, a property that is particularly useful in wound dressing and synthetic soil applications.

[00227] The present invention suitably provides a method of forming a polymeric foam. The method suitably comprises contacting a foamable polymer (preferably in situ during its formation) with a blowing agent and a copolymer compound (suitably as defined herein). The copolymer compound may be pre-mixed with the blowing agent, suitably as part of a blowing agent composition comprising said copolymer compound. Alternatively, the copolymer compound may be premixed with the or a component used to form the foamable polymer (e g. pre-mixed with a monomer, such as a polyol, of the formable polymer). Alternatively, the copolymer compound may be pre-mixed with one or more additives which are additionally contacted with the foamable polymer (preferably in situ during its formation). Alternatively, the copolymer compound may be contacted with the foamable polymer as part of a separate copolymer compound composition. The copolymer compound suitably stabilises the polymeric foam during and/or after foaming. The blowing agent suitably causes foaming and/or expansion of the foamable polymer. The foamable polymer (e g. a polyurethane) is suitably formed (by polymerisation) substantially simultaneously with foaming (e g. as it is dispensed with or contacted with a blowing agent).

[00228] In an embodiment, the polymeric foam may be formed by contacting a polymerizable or polymerising mixture (i.e. a mixture that is polymerizable or in the process of polymerising to form a foamable polymer, suitably a mixture comprising monomers for forming the foamable polymer, such as a polyurethane polymer) with a blowing agent or blowing agent composition (e g. water, an aqueous composition, carbon dioxide, air, chlorinated fluorocarbons CFCs) a copolymer compound (suitably as defined herein), and optionally one or more additives. The polymeric foam may be formed by dispensing a polymerizable mixture of comonomers (e g. polyurethane comonomers, suitably as defined herein) with the blowing agent, copolymer compound, and optionally one or more additives. The polymerizable or polymerising mixture suitably polymerises and, by virtue of its contact with the blowing agent, foams in situ to form a polymeric foam (e g. polyurethane foam). The blowing agent suitably causes the polymerising mixture and foamable polymer to foam (e g. expand) in situ, suitably to the dimensions of any containment (e g. a purpose-built mold or mold cavity, or just into a space such as a space to be insulated or sealed) into which the foamable polymer and blowing agent is dispensed. As such, polymerizable comonomers are suitably stored, optionally under pressure, either in the same compartment (if unreactive until contacted with a reactant, such as a polymerisation catalyst) or in separate compartments (if premature reaction is likely), with the blowing agent, copolymer compound, and/or other additives (which may themselves be optionally stored premixed with any one or more of the comonomers, or separate therefrom), and suitably all ingredients are dispensed together. In an embodiment, one of the comonomers (preferably polyol(s)) is stored premixed with the blowing agent and optionally one or more additives, and another comonomer (preferably diisocyanate(s)) is stored separately therefrom, and the two mixtures are contacted with each other upon or after dispensation. In an embodiment, one of the comonomers (preferably polyol(s)) is stored premixed with the copolymer compound - suitably, in such embodiments, another comonomer (preferably polyisocyanate(s)) is stored separate therefrom.

[00229] The blowing agent, or blowing agent composition, suitably comprises a copolymer compound as defined herein, suitably in admixture with the blowing agent (most suitably water).

[00230] The additives may comprise a polymerisation catalyst. The additives may comprise a surfactant. The additives may comprise a copolymer compound as defined herein.

[00231] A monomer (for forming the polymeric foam), or monomer composition, suitably comprises a monomer and a copolymer compound as defined herein. In such embodiments, the monomer is suitably a liquid at SATP. In such embodiments, the copolymer compound is suitably dissolved within the monomer. Such a monomer composition may further comprise a blowing agent. Such a monomer composition may further comprise one or more additives, optionally including a polymerisation catalyst and/or polymerisation initiator.

[00232] In a particular embodiment, the polymeric foam is formed by mixing together polymerizable monomer(s), a blowing agent, a copolymer compound as defined herein, and optionally a polymerisation catalyst, and allowing the monomers to polymerise and form a foam in situ. In a particular embodiment, a polyurethane foam is formed by mixing together diisocyanate monomer(s) (since optionally more than one diisocyanate compound may be included, depending on desired properties), polyol monomer(s) (since optionally more than one polyol compound may be included, depending on desired properties), a blowing agent (suitably water), a copolymer compound as defined herein, and optionally a polymerisation catalyst (e g. DMEA) and/or polymerisation initiator, and allowing the comonomers to polymerise and form a foam in situ. In a particular embodiment, a polyurethane foam is formed by mixing together a 1 :3 mixture of Voranol™ 3322 and Voranol™ 1447, a polyisocyanate monomer (SPECFLEX NE 112), a blowing agent (suitably water), a copolymer compound as defined herein, and optionally a polymerisation catalyst (e g. DMEA), and allowing the comonomers to polymerise and form a foam in situ.

[00233] Wherever the polymeric foam is formed within a mold, suitably said polymeric foam may be removed from said mold to provide the polymeric foam, suitably in the form of a shaped polymeric foam.

[00234] Suitably, regardless of how the polymeric foam is formed, the blowing agent (or blowing agent composition) suitably either comprises or is mixed with a copolymer compound, as defined herein, before or during foaming, suitably to facilitate stabilisation of any resulting foam.

[00235] According to a further aspect of the present invention there is provided a polymeric foam dispenser, comprising a dispensing nozzle in fluid connection (or conduit) with, or fluidly connectable with, one or more reservoirs containing (separately or as one or more mixtures) polymerizable monomers for forming the a foamable polymer (preferably two different monomers, suitably contained in separate reservoirs), a blowing agent (or blowing agent composition), a copolymer compound, and optionally one or more additives (e g. polymerisation catalyst). Again, the copolymer compound may be pre-mixed with the blowing agent, a monomer, an additive, or be used in its own separate composition. Most suitably the copolymer compound is dissolved in a monomer (e g. polyol(s)) or the blowing agent. The dispenser is suitably operable to dispense the contents of the reservoir(s) (substantially) simultaneously, suitably such that a foam or expanding foam is dispensed. The dispenser may be a hand-held device, such as a spray foam, or a machine in a manufacturing facility. The dispenser may be arranged as part of a larger system to dispense a polymeric foam into a mold. The larger system may be configured to remove the polymeric foam from the mold.

[00236] The present invention provides a kit of parts for producing a polymeric foam (a polymeric foam kit), the kit comprising: a) polymerizable monomer(s) for forming a foamable polymer; b) a blowing agent; c) a copolymer compound as defined herein; and d) optionally one or more additives; wherein optionally the blowing agent comprises or is pre-mixed with the copolymer compound and/or one or more of the polymerizable monomer(s) comprises or is pre-mixed with the copolymer compound.

[00237] In a particular embodiment, the kit comprises: a) polymerizable monomer(s) for forming a foamable polymer; b) a blowing agent; c) a copolymer compound as defined herein; and d) optionally one or more additives; wherein optionally the blowing agent comprises or is pre-mixed with the copolymer compound and/or one or more of the polymerizable monomer(s) comprises or is pre-mixed with the copolymer compound.

[00238] In a particular embodiment, the kit comprises: a) a first polymerizable monomer (or first monomer composition or mixture - e g. a mixture of variants of the same category of monomer, for example a mixture of polyols); b) a second polymerizable monomer (or second monomer composition or mixture - e g. a mixture of variants of the same category of monomer, for example a mixture of polyisocyanates); c) a blowing agent; d) a copolymer compound as defined herein; and e) optionally one or more additives; wherein optionally the blowing agent comprises or is pre-mixed with the copolymer compound and/or one or more of the polymerizable monomer(s) comprises or is pre-mixed with the copolymer compound; wherein preferably the one or more additives comprise a polymerisation catalyst.

[00239] In a particular embodiment, the kit comprises: a) one or more polyol monomers; b) a (polyisocyanate) diisocyanate monomer; c) a blowing agent composition comprising water and a copolymer compound as defined herein; and d) optionally one or more additives; wherein preferably the one or more additives comprise a polymerisation catalyst.

[00240] In a particular embodiment, the kit comprises: e) one or more polyol monomers pre-mixed with a copolymer compound as defined herein; f) a (polyisocyanate) diisocyanate monomer; g) a blowing agent (e.g. water); and h) optionally one or more additives; wherein preferably the one or more additives comprise a polymerisation catalyst.

[00241] Suitably, the ingredients of any of the aforesaid kits may be provided within or as part of the aforesaid polymeric foam dispenser.

[00242] Suitably, the ingredients of any of the aforesaid kits may be combined into a single composition, namely a foamable polymeric composition or foamable polymerizable composition. [00243] The present invention further provides a foamable polymeric composition or foamable polymerizable composition, the composition comprising either a foamable polymer or at least one polymerizable monomer for forming the foamable polymer, and a copolymer compound as defined herein. The foamable polymeric composition or foamable polymerizable composition suitably additionally comprises a blowing agent, most suitably water. Suitably, the at least one polymerizable monomer contained within the composition is incapable of polymerising within the composition, suitably without further intervention (e g. addition of a catalyst and/or addition of a further polymerizable monomer/comonomer).

[00244] In an embodiment, the foamable polymerizable composition comprises a first polymerizable monomer or first monomer composition (optionally comprising a mixture of “first” monomers), for forming a foamable polymer (e g. a polyurethane), a blowing agent (e.g. water), a copolymer compound (as defined herein), and optionally one or more additives. In an embodiment, the first polymerizable monomer is one or more polyol(s). Such a foamable polymerizable composition is suitably contacted with a second polymerizable monomer or second monomer composition (optionally comprising a mixture of “second” monomers) to produce a polymeric foam. In an embodiment, the second polymerizable monomer is a polyisocyanate (e g. diisocyanate) or mixture of polyisocyanates.

[00245] In an embodiment, the kit comprises a foamable polymeric composition or foamable polymerizable composition. Where the kit comprises a foamable polymerizable composition, the kit suitably further comprises a second polymerizable monomer(s), which when reacted together with the first polymerizable monomer(s) forms the foamable polymer or polymeric foam.

[00246] The present invention further provides a blowing agent composition. The blowing agent composition suitably comprises a copolymer compound as defined herein. Most suitably, the blowing agent composition comprises water and the copolymer compound. The blowing agent composition is suitably for forming a polymeric foam. Suitably any of the aforesaid embodiments and aspects involving contacting a foamable polymer or polymerizable I polymerising monomers with a blowing agent to form a polymeric foam may have the blowing agent substituted with a blowing agent composition of the invention. In some embodiment, the blowing agent composition may further comprise one or more optional additives, for instance, a polymerisation catalyst.

[00247] The present invention provides a surfactant-containing monomer composition. The monomer composition comprises a polymerizable monomer(s) and a copolymer compound as defined herein. In such embodiments, the monomer is suitably a liquid at SATP. In such embodiments, the copolymer compound is suitably dissolved within the monomer. Such a monomer composition may even further comprise a blowing agent. Such a monomer composition may further comprise one or more additives, optionally including a polymerisation catalyst and/or polymerisation initiator.

[00248] Most preferably, the polymer, foamable polymer, and matrix polymer is a polyurethane. The polyurethane is suitably a (optionally linear) polymer having a carbamate (or urethane) polymeric backbone. A polyurethane is suitably formed by reacting one or more polyols with one or more polyisocyanates (preferably diisocyanates), most suitably by reacting one or more polyols with a polyisocyanate (e g. diisocyanate). Suitably, in systems where foamable polymers are formed in situ, the polyols are kept separate from the diisocyanate(s) until dispensation or until polymerisation is desirable.

[00249] The diisocyanate is suitably selected from the group consisting of: methylene diphenyl diisocyanate (MDI), toluene diisocyanate (TDI), a polymeric isocyanate (PMDI) suitably derived by phosgenation of aniline-formaldehyde polyamines, 1 ,5-naphthalene diisocyanate, bitolylene diisocyanate, hexamethylene diisocyanate, poly(hexamethylene diisocyanate), m- xylylene diisocyanate, trans-1 ,4-cyclohexylene diisocyanate, tetramethylene diisocyanate, octamethylene diisocyanate, 3,3’-dimethyl-4,4’-biphenylene diisocyanate, Naphthalene diisocyanate, Isophorone diisocyanate, and any combination thereof. In an embodiment, the diisocyanate is methylene diphenyl diisocyanate (MDI). In an embodiment, the diisocyanate is toluene diisocyanate (TDI). In an embodiment, the diisocyanate is a polymeric isocyanate (PMDI), suitably derived by phosgenation of aniline-formaldehyde polyamines. In an embodiment, the diisocyanate is 1 ,5-naphthalene diisocyanate. In an embodiment, the diisocyanate is bitolylene diisocyanate.

[00250] The polyols(s) suitably comprise, suitably on average, at least 2 hydroxy groups per molecule, more suitably at least 3 hydroxy groups per molecule, more suitably at least 4 hydroxy groups per molecule. In an embodiment, the polyol(s) comprise at least two different types of polyol. The polyols may contain other functional groups like esters, ethers, amides, and ureas. In an embodiment, the polyol(s) comprise polyether polyol(s). The polyether polyol(s) may be or comprise polyethylene glycol, polypropylene glycol, glycerol propoxylate, and polytetramethylene glycol. Alternatively or additionally, the polyol(s) may comprise polyester polyol(s), suitably derived from saturated aromatic carboxylic acids and diols. In an embodiment, the polyol(s) are selected from the group consisting of alkyl polyols, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, pentaerythritol, glycerol, sucrose, sorbitol, 1 ,4-cyclohexanedimethanol, and any combination thereof.

[00251] Suitably, additives may comprise or consist of one or more catalysts, most suitably a single catalyst. The catalyst(s) suitably increase the rate of polymerisation to form the matrix polymer. The catalyses) suitably increases the rate of reaction between the polyol(s) and diisocyanate(s) during formation of the polyurethane. The catalyst(s) may be or comprise a metal salt. The catalyses) may be or comprise an amine. Additives may comprise (or additionally comprise) a flame retardant, suitably to reduce fire risks. In an embodiment, the catalyst is DMEA.

[00252] Whilst the polymeric foam, the polymeric foam kit, the foamable polymeric composition or foamable polymerizable composition, the blowing agent composition, surfactant-containing monomer composition, the polymeric foam dispenser, and the method of generating/forming a polymeric foam, may be defined by any of the features or embodiments disclosed herein in relation to a corresponding foamed composition, foamable composition (e g. those of numbered paragraphs C1 to C14), foamable composition dispenser, and method of manufacturing a foamable composition, the following numbered paragraphs J1 to J50 disclose specific embodiments:

J1 . A polymeric foam comprising a copolymer compound as defined herein, wherein suitably the polymeric foam is a cellular polymeric matrix comprising a foam cells distributed with a polymeric matrix, suitably with the copolymer compound present at the internal surface of the cells, wherein the polymeric matrix suitably comprises a matrix polymer (which is suitably the same as a foamable polymer used to produce the polymeric foam).

J2. The polymeric foam of J1 , wherein the foam cells are gas bubbles.

J3. The polymeric foam of J1 to J2, wherein the polymeric foam is an open cell foam (or a variant thereof as defined herein, such as with a % volume of cells).

J4. The polymeric foam of J1 to J2, wherein the polymeric foam is a closed cell foam (or a variant thereof as defined herein).

J5. A foamable polymeric composition comprising a foamable polymer and a copolymer compound as defined herein. The foamable polymeric composition may further comprise a blowing agent and optionally one or more additives.

J6. A foamable polymerizable composition comprising at least one (i.e. a first) polymerizable monomer for forming a foamable polymer, and a copolymer compound as defined herein. The foamable polymerizable composition may further comprise a blowing agent and optionally one or more additives.

J7. A blowing agent composition comprising a blowing agent and a copolymer compound as defined herein.

J8. A surfactant-containing monomer composition comprising a monomer or monomer mixture and a copolymer compound as defined herein.

J9. A polymeric foam kit comprising a foamable polymer or polymerizable monomer(s) for forming the foamable polymer, a blowing agent, a copolymer compound as defined herein, and one or more additives. The blowing agent and copolymer compound may be combined with a blowing agent composition comprising the blowing agent and copolymer compound. Polymerizable monomer(s) may be combined with the copolymer compound, optionally additionally with the blowing agent.

J10. A polymeric foam kit comprising a foamable polymer or polymerizable monomer(s) for forming the foamable polymer and the blowing agent composition of J7.

J11. A polymeric foam kit comprising a polymerizable monomer(s) for forming a foamable polymer, a copolymer compound mixed with one of the polymerizable monomers, and a blowing agent.

J12. A polymeric foam kit comprising the foamable polymerizable composition of J6 and a further (i.e. a second or subsequent) polymerizable monomer for forming the foamable polymer.

J13. A polymeric foam kit comprising at least one (i.e. a first) polymerizable monomer(s) for forming a foamable polymer, a further (i.e. a second or subsequent) polymerizable monomer(s) for forming the foamable polymer, a copolymer compound as defined herein, a blowing agent, and optionally one or more additives. The kit may comprise a blowing agent composition comprising both the blowing agent a copolymer compound. The blowing agent composition may further comprise any one or more of the optional one or more additives. The kits may alternatively comprise a surfactant-containing monomer composition comprising the (e g. first) polymerizable monomer(s) and the copolymer compound.

J14. A polymeric foam dispenser comprising a copolymer compound as defined herein.

J15. A polymeric foam dispenser comprising a dispensing nozzle in fluid connection with, or fluidly connectable with, one or more reservoirs containing (separately or as one or more mixtures) the parts of any of the polymeric foam kits as defined herein, most suitably as defined in J9 to J13.

J16. A method of generating/forming a polymeric foam, comprising contacting a foamable polymer (suitably in situ during its formation) with a blowing agent, a copolymer compound as defined herein, and optionally one or more additives. The method may comprise contacting the foamable polymer (suitably in situ during its formation) with a blowing agent composition as defined herein, and optionally one or more additives.

J17. A method of generating/forming a polymeric foam, comprising contacting (or mixing together, or simultaneously dispensing) at least one (i.e. a first) polymerizable monomer for forming a foamable polymer, a further (i.e. a second or subsequent) polymerizable monomer for forming the foamable polymer, a copolymer compound as defined herein, a blowing agent, and optionally one or more additives.

J18. A method of generating/forming a polymeric foam, comprising contacting the parts of any of the polymeric foam kits as defined herein, suitably a kit as defined in J9 to J13.

J19. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J1 to J18, wherein the copolymer compound is defined according to any of A1 to A28 and/or any of B1 to B13.

J20. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J1 to J19, wherein the copolymer compound is defined by Formula la: poly(M₁-co-M₂) or by Formula Ila: poly(M₁-stat-M2), wherein suitably the weight ratio of M₁ to M₂ in the copolymer compound is between 3:1 and 1 :3, preferably between 2:1 and 1 :2.

J21. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J20, wherein at least 1000 parts by mass of water are required to dissolve 1 part by mass of M₁ and at most 10 parts by mass of water are required to dissolve 1 part by mass of M₂.

J22. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J20, wherein M₁ has a logP value greater than 1.5 (suitably greater than 3, more suitably greater than 4) and M₂ has a logP value less than 1 .5 (suitably less than 1 , more suitably less than 0).

J23. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J1 to J22, wherein wherever the copolymer compound comprises a (perfluorocarbon group, said (per)fluorocarbon group is part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide, suitably wherein the copolymer compound is otherwise free of fluorine atoms.

J24. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J1 to J23, wherein wherever the copolymer compound comprises a siloxane (suitably methyl siloxane moiety or perfluoromethyl siloxane moiety) group, said group is part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide, suitably wherein the copolymer compound is otherwise free of silicon atoms.

J25. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J20 to J24or any preceding paragraph dependent thereon, wherein M₁ comprises pendent groups (RT) comprising a continuous carbon chain comprising at least 3 carbon atoms, one or more branched hydrocarbyl moieties, and at least one methyl (CH₃) group; whereas M₂ comprises pendent groups (R₂) having a chain length of at least 3, suitably at least 5, suitably at least 7, comprising two or more hetero atoms, that are free of any methyl groups (optionally except for methyl groups attached to heteroatoms; or optionally terminal methyl groups, especially when attached to heteroatoms, such as may be the case for PEGA and PEGMA).

J26. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J20 to J25or any preceding paragraph dependent thereon, wherein M₁ comprises pendent groups (RT) comprising a continuous carbon chain comprising at least 5 carbon atoms and at least two methyl (CH₃) groups; whereas M₂ comprises pendent groups (R₂) comprising at least one polyether or polyester moiety, preferably at least one polyoxyalkylene (preferably polyoxyethylene) moiety comprising at least two oxyalkylene (preferably oxyethylene) monomeric units.

J27. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J1 to J26, wherein the copolymer compound has a homogeneous polyacrylic backbone or a homogeneous polyalkylacrylic backbone.

J28. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J1 to J26, , wherein the copolymer compound has a polyacrylic backbone.

J29. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J20 to J21 or any preceding paragraph dependent thereon, wherein M₁ is selected from the group consisting of TMHA, TMHMA, EHA, iOA, and M₂ is selected from the group consisting of PEGA, AA, PEGMA, MAA, and GMA.

J30. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J29, wherein M₁ is TMHA and M₂ is PEGA.

J31. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J30, wherein the copolymer compound has the Formula poly(PEGA-stat-TMHA).

J32. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J31 , wherein the weight ratio of PEGA:TMHA is between 2:1 and 1 :2.

J33. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J1 to J32, wherein the composition is free of silicon and/or fluorine-containing surfactants.

J34. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J1 to J33, wherein the matrix polymer or foamable polymer is a polyurethane.

J35. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J34, wherein the foamable polymer (or matrix polymer) is a polyurethane, and at least one (i.e. a first) polymerizable monomer for forming the foamable polymer is or comprises a polyol, and a further (i.e. a second or subsequent) polymerizable monomer for forming the foamable polymer is or comprises a polyisocyanate.

J36. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J34 to J35, wherein the foamable polymer (or matrix polymer) is a polyurethane formed from at least one polyol monomer and at least one polyisocyanate monomer. J37. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J36, wherein the foamable polymer (or matrix polymer) is a polyurethane formed from at least one polyol monomer and at least one diisocyanate monomer.

J38. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J37, wherein the foamable polymer (or matrix polymer) is a polyurethane formed from at least two polyol monomers and a single diisocyanate monomer.

J39. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J35 to J38, wherein the polyol(s) is selected from the group consisting of a polyether polyol, a polyester polyol, a polycarbonate polyol, a polycaprolactone polyol, a polybutadiene polyol, a polysulfide polyol, an alkyl polyol, and any combination thereof.

J40. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J39, wherein the polyol(s) is one or more polyether triols, suitably having a molecular weight between 3000 and 5000 g/mol, and a hydroxyl number between 30 and 60 mg KOH/g.

J41. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J35 to J40, wherein the polyisocyanate is selected from the group consisting of toluene diisocyanate (TDI), methylene diphenyl diisocyanate (MDI), a polymeric methylene diphenyl diisocyanate, 1 ,6-hexamethylene diisocyanate (HDI), 1-isocyanato-3-isocyanatomethyl-3,5,5-trimethyl-cyclohexane (isophorone diisocyanate (IPDI), 4,4 ' -diisocyanato dicyclohexylmethane, (H₁₂MDI or hydrogenated MDI), and any combination thereof.

J42. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J41 , wherein the polyisocyanate is toluene diisocyanate (TDI) or methylene diphenyl diisocyanate (MDI).

J43. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J1 to J42, wherein the blowing agent is a gas or a liquid at SATP.

J44. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J43, wherein the blowing agent is or comprises water.

J45. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J1 to J44, wherein the one or more additives comprise a polymerisation catalyst and/or polymerisation initiator.

J46. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J45, wherein the polymerisation catalyst is a basic catalyst (e g. tertiary amine) of an acidic catalyst (metal lewis acids, e g. dibutyltin dilaurate).

J47. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J46, wherein the polymerisation catalyst is selected from the group consisting of triethylenediamine, 1 ,4-diazabicyclo[2.2.2]octane (DABCO), dimethylcyclohexylamine (DMCHA), dimethylethanolamine (DMEA), bis-(2-dimethylaminoethyl)ether, and any combination thereof.

J48. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J1 to J47, wherein the aforesaid are free of silicon-containing compounds. J49. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J1 to J48, wherein the aforesaid are free of fluorine-containing compounds.

J50. The polymeric foam, foamable polymeric composition, foamable polymerizable composition, blowing agent composition, surfactant-containing monomer composition, polymeric foam kit, polymeric foam dispenser, or method of J1 to J49, wherein the aforesaid additionally comprises one or more additives selected from chain extender(s), crosslinker(s), surfactant(s), flame retardant(s), pigment(s), colourant(s), and fillers).

EXAMPLES

[00253] The present invention is now further illustrated by way of the following non-limited examples.

MATERIALS

[00254] Glyceryl monomethacrylate (GMA), poly(ethylene glycol) methyl ether acrylate (PEGA, M_n = 400 and 5000 Da), poly(ethylene glycol) methacrylate (PEGMA-OH, M_n = 300 Da), acrylic acid (AA), methacrylic acid (MAA), polypropylene glycol) acrylate (PPGA, M_n = 475 Da), polypropylene glycol) methacrylate (PPGMA, M_n = 375 Da), diethylene glycol ethyl ether acrylate (DEGA), dimethyl acrylamide (DMA), lauryl acrylate (LA), lauryl methacrylate (LMA), iso-decyl acrylate ('DA), iso-octyl acrylate ('OA), ethylhexyl acrylate (EHA), ethylhexyl methacrylate (EHMA), iso-bornyl acrylate ('BA), tert-butyl acrylate (*BuA), tert-butyl amino ethyl acrylate (tBuAEA), 3,5,5-trimethylhexyl acrylate (TMHA), 3,5,5-trimethylhexyl methacrylate (TMHMA), N-tert-octyl acrylamide (OAA), 3-Tris(trimethylsiloxy)silylpropyl methacrylate (TMSMA), hexafluorobutyl methacrylate (HFBMA), isobornyl acrylate (iBoA), and 2,2,2-trifluoroethylmethacrylate (TFEMA), were all purchased from Alfa Aesar, Sigma Aldrich, Fisher, or ABCr, and all used as received. Asoisobutyronitrile (AIBN) was recrystallized twice from methanol. Ethanol, methanol and heptane (Fisher) were used as received. 3-mercaptopropanoic acid (MPA), 1 -dodecanethiol (DDT), isopropyl alcohol (IPA) and ethanol (EtOH) were all purchased from Alfa Aesar or Sigma Aldrich and used as received. Water was twice distilled prior to use. Voranol 1447, Voranol 3322, and TEGOstab were purchased from Dow Chemical.

Copolymers formed from Acrylate and Methacrylate-based Comonomers

[00255] Some of the ensuing examples of copolymer surfactants were produced using the following monomers, which were selected to illustrate broader principles. For instance, an acrylate-based polymer backbone is not believed to be an essential requirement, nor is the specific nature of pendent groups. The inventors do, however, believe that copolymers of the invention should ideally include both solvophobic and solvophilic monomers - the reference solvent system being that of any relevant foaming medium.

[00256] As such, the following solvophobic example monomers were deployed:

Scheme 1 - Solvophobic Monomers

[00257] The following solvophilic example monomers were deployed:

PEGMA-GH

Scheme 2 - Solvophilic Monomers GENERAL SYNTHESES

General Procedure for the Synthesis of polymer surfactants

[00258] Representative synthesis of PEGA-stat-TMHA with a hydrophilic monomer feed fraction of 0.5 (fi = 0.5): AIBN (2 mg) was weighed into a 7 ml vial, followed by the desired mass of PEGA (0.2 g) and TMHA (0.2 g) (see Scheme 1 and Scheme 2 above). Finally, ethanol (2 g) was weighed into the vial in order to afford a monomer concentration of ca. 20 wt%. A magnetic follower was added to the vial before it was sealed by suba seal. After vortex mixing for 10 s to achieve a homogeneous solution, the reaction mixture was degassed by sparging with nitrogen gas for 20 min. The vial was then submerged in an oil bath at 70 °C and stirred for 4 h. After this time the vial was removed from the oil bath, and the solvent and unreacted monomer were removed overnight at 70 °C in a vacuum oven. Polymers were analysed by ¹H NMR in CDCI₃ and GPC in THF. Monomer mass fractions are either reported with respect to hydrophobic or hydrophilic monomer fraction in the feed (fi orf₂, respectively), orwith respect to hydrophobic or hydrophilic monomer mass fraction measured by ¹H NMR analysis (rm or m₂, respectively). Copolymer surfactant composition can also be expressed in terms of HLB, which is calculated from the hydrophilic monomer mass fraction by the equation below:

HLB = 20 X m₂

[00259] Methods for controlling M_n and D of PEGA-stat-TMHA. (1) Free radical initiator control: The synthetic procedure above was modified to include 10-fold concentration of AIBN (i.e., 10 wt%). (2) Thiol chain transfer agents: 3- mercaptopropanoic acid (MPA) or 1 -dodecanethiol (DDT), which are known to be effective chain transfer agents for free radical polymerisations with acrylic monomers, were added to the above procedure in variable ratios with respect to AIBN. For DDT, AIBN:thiol ratios used were 10:1 , 8:1 and 5:1 , and for MPA, AIBN:thoil ratios of 100:1 , 80:1 , 60:1 , 50:1 , 20:1 , and 10:1. (3) Solvent mixtures: mixed solvent systems comprising ethanol and isopropyl alcohol (IPA) were prepared with 10:90, 25:75, 50:50, 75:25, 90:10, and 95:5 EtOH:IPA by volume and used in place of pure ethanol as the reaction solvent. The specifics of these techniques are outlined below, and a full set of molecular weight data is presented in Table 3.

High-throughput synthesis of polymer surfactants

[00260] After designing experiments using Jmp® software, a number of 2 ml vials were taped together into a “multi-vial” structure. A stock solution of AIBN in ethanol (50 mg in 5 ml) was prepared. Monomers were measured into the 2 ml vials volumetrically, before adding 0.4 ml of AIBN stock solution and a magnetic flea. Vials were sequentially degassed under a flow of nitrogen for 10 mins, during which time the ethanol evaporated. Degassed ethanol (0.4 ml) was then replaced in each vial, and the vials were submerged in at water bath at 70 °C for 4 h, with stirring. Solvent and unreacted monomer were removed in a vacuum oven at 70 °C overnight.

Polyurethane foam synthesis

[00261] Formulations comprising of Voranol 3322 (25 parts) and Voranol 1447 (75 parts), DMEA (1.5 parts), water (4 parts) and surfactant (1 part) were mixed into a 1 pint plastic cup. This formulation was designed to afford a material with mostly open cells. The isocyanate Specflex NE 112 (75 parts) was added and the mixture homogenised at 3000rpm, before being transferred to an empty plastic cup in which the foam expansion took place, and video was recorded on a Sony Xperia camera phone.

PROPERTIES OF FOAMS

[00262] Foams are essentially characterised by pockets of gas (e g. gas bubbles) trapped within a liquid, or potentially even trapped within a solid. Liquid foams may be wet or dry.

[00263] FIG. 2 shows schematic representations of a wet and dry foam, with gas bubbles amongst a solvent system. The left image may be considered a substantially wet foam since the gas bubbles are separated by a reservoir of solvent. The right image corresponds to a dry foam where gas bubbles are closer together with less solvent in between. As a foam dries, gas bubbles may be susceptible to coalescence and bursting, which results in foam reduction. As such, it is desirable to stabilise these gas bubbles and mitigate coalescence, Ostwald ripening and bursting. As such, the invention seeks to stabilise such foams using particular copolymer surfactants.

[00264] FIG. 3 is a schematic representation of block-copolymer surfactant molecules arranged at the surface of a gas bubble. Here, the solvophobic portions of the block copolymer (and said block’s polymeric backbone) are oriented towards the gas bubble, whlist the solvophilic portions of the block copolymer (and its corresponding polymeric backbone) lie substantially within the solvent surrounding the gas bubble. In this manner the surfactant molecules inhibit coalescence, Ostwald ripening, and bursting of gas bubbles via steric and/or electrostatic interactions, and other mechanisms.

[00265] FIG. 4 is a schematic representation of a statistical, random, or alternating copolymer surfactant molecules arranged at the surface of a gas bubble. In contrast to the block copolymer surfactants illustrated in FIG. 3, the backbones of these statistical, random, or alternating copolymers effectively align at the gas bubble interface such that solvophobic moieties (of solvophobic monomers) to are oriented towards the gas bubble and solvophilic moieties (of solvophilic monomers) lie substantially within the solvent surround the gas bubble. The surfactant molecules inhibit coalescence, Ostwald ripening, and bursting of gas bubbles via steric and/or electrostatic interactions, and other mechanisms. As such, the statistical, random, or alternating copolymer molecules may act as a surfactant by adsorbing to bubble interfaces, albeit they align differently to the aforesaid block copolymers.

[00266] The differences in how the aforesaid surfactant types align at the gas bubble interface are also reflected in their solution phase behaviour.

[00267] FIG. 5 is a schematic representation of the multi-molecular micelles formed by block copolymers in solution singlemolecule micelle thought, by the inventors, to be formed by statistical, random, or alternating copolymer surfactant molecules in solution. For block copolymer surfactants to act as foam stabilisers, they must first dissociate from their micelle state, diffuse through solvent and thereafter collect at a gas bubble interface. This poses a kinetic barrier, and may also pose a thermodynamic barrier depending on the relative Gibbs Free Energy of the micelle solution vs stabilised foam. For statistical, random, or alternating copolymer surfactants to act as foam stabilisers, they must first unfold from their micellar state and thereafter collect at a gas bubble interface. Though this poses a kinetic barrier, it is not as onerous as that for multimolecular micelles, as per block copolymers. It is difficult to assess thermodynamic barriers, since solvent-based entropic factors are difficult to model.

[00268]

TESTING PROTOCOLS

Foaming studies

[00269] After purification under vacuum, 5 mg neat polymer was weighed into a 7 ml vial, and dissolved in 1 ml ethanol. This mixture was vortexed for 10 seconds and visually inspected for the appearance of bubbles. Water was then added in 0.1 ml aliquots, and foaming tested by vigorous vortex mixing of the vials for 10 seconds. If a foam was observed with a lifetime greater than 5 s, the foam height (h) was measured. This was measured from the top of the liquid to the top of the foam immediately after agitation. To compare data from different experiments, foamability (F) was calculated from Equation (1), based on the initial volume of surfactant solution (V) and vial radius (r). This value effectively described the foam volume as a ratio normalised with respect to the original solution volume.

[00270] For large scale foamability testing, surfactant solutions (1 -3 wt%, > 40 ml) were prepared and transferred into a custom-built automated hand pump dispenser, as used with current alcohol-based foam sanitisers in healthcare environments. A 3 wt% solution of the incumbent silicone-based surfactant was also prepared for direct comparison. The foam dispenser was operated by an automatic rotating cam which could be programmed to different push speeds. Foam produced from the first three pushes was discarded, then the following three were collected in a volumetric measuring cone. The total volume recorded from these 3 pushes is representative of the volume of alcohol-based foam recommended per use by healthcare workers. Foam volumes created by copolymer surfactants were compared to foams created from the incumbent technology at 3 different push speeds (0.3, 0.5 and 0.7 s).

Testing barrier properties of copolymer surfactants

[00271] Porous polyether sulfone (PES) membranes were used as model skin substrates. Neat surfactants (PEGA-s/at- TMHA and one silicone-based) were deposited dropwise onto the glossy surface of the PES dropwise until a total of 8 mg had been infused into the pores. These coated substrates were placed inside a Transepidermal Water Loss (TEWL) cell filled with 0.75 g of distilled water and sealed with an o-ring. Mass loss was measured over time (in triplicate) to determine the resistance to water loss afforded by the surfactant coatings.

Aqueous Film Forming Foam Tests

[00272] Surfactant was dissolved in ethanol/water (1/2 by volume) at 1.5 wt%, and 10 ml of the solution transferred into a 100 ml measuring cylinder. The solution was foamed within the cylinder using an air stone pump (FoamKit Deluxe, 100%Chef) by submerging the air stone at the base of the cylinder. After 10 s, the air stone was slowly removed and a portion of the foam decanted onto the surface of heptane contained in a petri dish. Foam collapse was recorded on an Sony Xperia camera phone and stability on heptane was judged by the time taken for the foam to completely disappear.

Bubble Pressure Tensiometry

[00273] Surface tension analyses were performed on a Kruss Bubble Pressure Tensiometer. Solutions of copolymer (20 wt%) were prepared in 50-60 % ethanol by weight. Pure solvent (70 ml) was transferred to the beaker and an initial baseline surface tension was measured. Surfactant solution was then added to the solvent in 1.5 ml aliquots, and a measurement taken at each concentration. Surface tension data were collected at surface ages from 10 to 1000 ms.

Small-angle X-ray scattering (SAXS) analysis of foaming solutions

[00274] SAXS analysis was conducted on a Xenocs Xeuss 2.0 with a MetalJet X-ray source and Pilatus 1 M detector. Samples were prepared by dissolving a desired mass of surfactant in a desired ethanol/water mixture and transferred into 2mm borosilicate capillaries. Samples and solvent backgrounds were run with 3 x 600 s exposures and data collected at a camera length of 1 .2 m (calibrated by silver behenate). Data were processed in Foxtrot and Igor Pro software.

EXAMPLE 1 - Foaming in Alcohol-Water Mixtures (Hand-Sanitizer Simulations)

[00275] The multitude of monomers applied in this study (see Scheme 1 and Scheme 2 above) enabled rapid screening of a range of monomer chemistries, and access to different copolymer architecture. The latter could be controlled through the pairing of monomer class: two acrylates or two methacrylates would give relatively random distributions, whereas the combination of one acrylate and one methacrylate would lead to a gradient structure due to the differing reactivity ratios. Furthermore, by varying the ratio of monomers within the feed, the hydrophobic-lipophilic balance (HLB) could be tuned.

[00276] The progress of polymerisation was followed by 1 H NMR analysis. After a typical 4h reaction, the monomer conversion was in the region of 85%, and longer syntheses run overnight reached >95% conversion. For all-acrylate systems, the ratio of monomers in the polymer was close to the feed ratio (Table 1). Unreacted monomer could be removed under vacuum at elevated temperature in most cases. GPC analysis gave number average molecular weight Mn = 10 - 20 kg/mol, and D = 2.0-2.5.

[00277] Initial foaming tests were conducted by agitating the surfactant solution using a vortex mixer. Surfactants were first dissolved in pure ethanol, before being sequentially diluted with water, and foamability being measured at each point as the volume of foam formed upon vortex agitation. This technique allowed rapid comparison of foamability in different surfactants at different ethanol concentrations. Results of foaming tests forthe first set of copolymers are presented in Table 2.

Table 1 - Examples of PEGA mass fraction obtained 1 H NMR analysis vs. feed fraction in PEGA-stat-TMHA, and conversion to an effective HLB

Table 2 - Properties and foamability of first generation polymers synthesised for this study

’See above for full list of monomer structures; ²monomer fraction based on mass fraction in feed; ³foamability calculated from equation 1

[00278] Higher foam ratios in Table 2 are indicative of greater foaming. From this initial screen of monomer chemistry, polymer architecture, and monomer fractions/HLB, a number of conclusions can be drawn concerning variables that influence the foaming properties. Firstly, the monomer structures clearly had an influence on overall foamability. Taking a series of polymers where PEGA was the hydrophilic block, the order of foamability was TMHA > iOA > EHA > LA ~ tBuA ~ OAA ~ DA. For a series of polymers with TMHA as the hydrophobic block, the foamability was in order PEGA > PGMA > AA > PPGMA. Evidently, the side chain structures play a role in foamability: more branched hydrophobic monomers and hydrophilic monomers with larger hydrophilic groups appear to enhance foamability.

[00279] There were also trends arising from the copolymer architecture, which results from the differing monomer reactivity. Superior foaming was achieved in all-acrylate systems (statistical/random distribution of monomers) relative to acrylate-methacrylate systems (gradient monomer distribution). Indeed, the cloudy appearance of mixtures containing gradient copolymers as water content increased suggested their solubility within the solvent was low, and large aggregates existed. Therefore, it appeared that a random distribution of monomers across the copolymer chain enabled higher solubility and also superior foaming properties than a gradient (“block-like”) structure (see PEGA-TMHA vs. PEGMA-TMHA or PEGA- EHA vs. PEGA-EHMA).

[00280] A number of syntheses were carried out in an attempt to control the chain length (i.e. M_n) and chain length distribution (i.e., polydispersity, D) of the surfactants and ascertain the effect of these variables on surfactant foamability. To achieve this, free radical initiator concentration, and a range of chain transfer agents (CTAs) were added to the syntheses including thiols (DDT or MPA) and cosolvents (IPA). For polymerisations run in the presence of MPA, the molecular weight decreased as the CTA concentration was increased, from 14.7 Da to 3.8 kDa, whilst D decreased from 2.1 to 1.5. Meanwhile, the presence of DDT did not effectively affect the M_n, but D was significantly reduced relative to conventional free radical polymerisation (ca. 1.6). Relevant results are presented in Table 3.

Table 3 - Composition of PEGA-TMHA copolymers synthesised with variable molecular weight (M_n) and poly dispersity index (D). Volume fractions of PEGA (f_PEGA) determined by ¹H NMR are displayed

[00281] IPA was employed as a cosolvent in the reaction in different ratios with ethanol, and the resulting number and weight average molecular weight (M_n and M_w, respectively) of the copolymers strongly depended on the solvent composition. In particular, the larger the proportion of IPA, the higher M_w and D. This was observable by multi-modal peaks apparent by GPC. Therefore, IPA evidently functioned as a branching agent, allowing a greater degree of branching to be introduced into the polymer. IPA is known to participate in chain transfer to solvent during free radical polymerisations which can enhance chain transfer to polymer and therefore lead to a more branched architecture.

[00282] The effect of M_n and D on foamability was studied by comparing PEGA-stat-TMHA prepared as described above (Table 3). Foamability measurements were conducted in 65% ethanol (by volume) and at constant concentration, and these data were analysed by statistical modelling within Jmp® software. Contour maps (not shown) of foamability vs D and foamability vs M_n were strongly skewed towards low D (i.e, < 2) and low M_n. Further studies may be necessary to ascertain which of M_n and D is the most significant, and whether interactions exist with other parameters.

[00283] The most promising candidates were taken forward for large scale testing within a model foam dispenser. PEGA- stat-TMHA was prepared in an EtOH/water mixture (1/1 by volume) and subjected to the standardised test for measuring foam volume in hand sanitisers (see experimental). 16 mL of foam resulted from three activations of the pump, which compared reasonably well with the incumbent PDMS-PEO block copolymer surfactant at equivalent concentration and ethanol/water mixture, in which 24 mL foam was produced. Optimisation was carried out as described below in order to bridge this gap in foamability.

[00284] According to data in Table 2, the ratio of hydrophobic and hydrophilic monomers within the copolymers (Mi, M₂), or the effective “HLB”, significantly affected foamability. However, from initial data it was unclear how this correlated with foamability, and whether interactions existed between variables. To better understand the key variables governing foamability of alcohol-water mixtures, a flexible fast filling design was employed (using JMP® software) to design a series of 30 experiments in which 3 parameters were varied (Table 4): the hydrophilic monomer mass fraction in the feed (0.66 > f_PEGA >0.33), ethanol volume fraction (0.7 > f_EtOH, > 0.5) and concentration (4 > wt%, > 0.4). In other words, a series of 30 PEGA-TMHA copolymers with different monomer fractions were synthesised on a small scale, and foamability tested in a different alcohol-water fraction and at a different concentration for each polymer. Simultaneous small scale syntheses enabled rapid purification and testing of multiple candidate foaming surfactants. The ethanol fraction can also be converted to mass fraction from the following equation: m_FtnH =

Table 4 - Variables output from the statistical model (f_PEGA, m/f_EtOH and wt%) to inform the high-throughput design of polymers, and results from the foamability study

Expt #

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

[00285] GPC analysis was used to confirm the reproducibility of these high throughput polymerisations, in orderto account for M_n as an additional variable potentially affecting foamability. The results of GPC analysis in THF for 6 different polymers from Table 4 are displayed in FIG. 6.

[00286] FIG. 6 is an array of overlapping GPC traces (Rl detector) from 6 different TMHA-stat-PEGA copolymers synthesised from the high throughput study as described above in Table 4.

[00287] Although the monomer ratios differed across these reactions, the resulting polymers all possessed a similar molecular weight and polydispersity, as indicated by the similar retention times. Across these samples, M_n was in the range 14.3 to 19.6 kg/mol, and dispersity between 2.27 and 2.40.

[00288] Based on the data presented in Table 4, JMP software was used to fit a model to the data to describe the contribution of each variable to the foamability (F), which included interactions between the variables. The derived equation (1) is presented below:

[00289] From this equation we can derive a number of conclusions: (i) lower mass fractions of hydrophilic component tend to increase foaming (i.e. f_PEGA < 0.5); (ii) increasing water content (i.e. decreasing f_EtOH) in the solvent increases the foamability, particularly above f_EtOH < 0.6; (Hi) an increased concentration of surfactant led to higher foamability in the range tested (0.4 to 4 wt%); (iv) a complex interaction exists between f_PEGA and f_EtOH, in which foamability at higher f_EtOH is increased by using a larger f_PEGA (and vice versa). Data obtained in these experiments can help design the optimal surfactant to foam under any given set of conditions (e g. solvent condition) that suite the required application. The model indicates that foamability could be enhanced from 1.35 (see Table 2) to 1.94 in a high alcohol sanitising solution: a 44% increase that would be equivalent to the current silicone-based surfactants.

Surfactant barrier properties

[00290] Polymer substrates (PES) coated with a layer of surfactant were used as a model system to study the barrier properties of a surfactant layer deposited on the skin after using a hand sanitiser. TMHA-stat-PEGA (m = 0.5) synthesised for the first generation of surfactants was tested against a benchmark PDMS-PEO block copolymer surfactant currently used in alcohol hand sanitiser foams (see FIG. 7). The slower loss of mass from a TEWL cell sealed with a TMHA-PEGA coated membrane indicated that the membrane was a better barrier against evaporation and/or more of a humectant. This combination of properties strongly suggested that a layer of TMHA-PEGA surfactant deposited onto the skin following hand sanitiser application would be more moisturising than the current PDMS-PEO block copolymer surfactant. This advantageous moisturising property imparted by TMHA-stat-PEGA within an alcohol sanitising foam could help to increase compliance for healthcare staff. Due to the unpleasant feel of present hand sanitisers on skin, it is common for healthcare staff to rinse their hands and apply moisturiser following sanitisation. Including a surfactant that also acted as a moisturiser could help to change these habits by reducing the number of steps in each sanitisation event, and increase overall day to day use of hand sanitisers.

[00291] FIG. 7 is a graph showing water loss against time from a study of PES membranes coated with either the incumbent PDMS-PEO block copolymer surfactants (open squares) or TMHA-stat-PEGA (closed triangles).

Additional Foamability Data

[00292] The following table (Table 4A) shows further formulation data obtained from additional foamability studies. The test protocols and polymers were substantially the same as those represented above in Table 2, though they additionally include data regarding foam stability (i.e. foam lifetime in seconds).

Table 4A - Foamability (foam height and foam lifetime) of first generation polymers synthesised for this study

[00293] Again, various ethanol-water mixtures were used to test foamability properties of a library of statistical copolymer surfactants prepared by free radical copolymerization (with varying mass fractions of hydrophobic monomers, as indicated).

[00294] Table 4B, below, shows further foamability data (foam height - foamability, and foam stability - foam lifetime in seconds) in respect of three statistical copolymer surfactants (with 0.5 mass fraction of hydrophobic monomers) in various ethanol-water mixtures (with ethanol mass fractions as indicated) where the aqueous component is either 1.0 M NaCI, or else a salt-free aqueous component at either pH 3 or pH 10.

Table 4B - Foamability (foam height and foam lifetime in seconds) of three statistical copolymer surfactants (0.5 mass fraction of hydrophobic monomers) in various ethanol-water mixtures (with ethanol mass fractions as indicated) with different aqueous components (1.0 M NaCI, salt-free pH 3, or salt-free pH 10)

[00295] It was conceived that the lower foamability observed for AA or MAA-based surfactants relative to neutral PEGA- based copolymers (as per Table 4A or Table 2) could be influenced by solution pH and ionic strength. Thus, additional foaming assays were performed for TMHA-stat-PEGA, TMHA-stat-AA and TMHMA-stat-MAA, using ethanol-aqueous mixtures in which the aqueous component was either 1 .0 M NaCI, or pH 3 or pH 10 water. Compared to the assay in which ultrapure water was used (Table 4A), the foam stability of TMHA-stat-PEGA was slightly reduced using water at pH 10 and remained largely unchanged when using 1.0 M NaCI or water at pH 3 (Table 4B). Meanwhile, foamability conferred by TMHA-stat-AA was marginally reduced in the presence of 1.0 M NaCI or at pH 3 but remains essentially unchanged at pH 10. TMHMA-stat-MAA only stabilized foams in the presence of 1.0 M NaCI. Overall, the foamability of copolymers containing ionizable units (AA or MAA) was not significantly enhanced by protonation (pH 3), deprotonation (pH 10) or charge screening (1 .0 M NaCI). This suggests that the surface activity is not significantly affected by the extent of ionization of these monomers under these conditions. Non-ionic TMHA-stat-PEGA remained surface-active and was able to stabilize foams in the presence of each type of modified aqueous phase (Table 4B). Such good performance over a range of conditions is likely to be a decisive advantage for potential industrial applications.

[00296] Table 4C demonstrates for both block and statistical copolymers, via 1H NMR data, that target mass fractions (of hydrophobic component) are achievable using corresponding input mass fractions and, via GPC data, that M_n (number averaged molecular weight) and M_w/M_n (polydispersity) distributions are substantially controllable by the aforesaid inputs.

Table 4C - Details of certain statistical and block copolymers with corresponding 1H NMR data and GPC data confirming monomer mass fractions in product and corresponding M_n and M_w/M_n (polydispersity) data.

^aby ¹H NMR analysis; ^bin THF against a series of PMMA calibration standards. [00297] As expected, the polydispersity of the statistical copolymers (made via free radical polymerisation, FRP) is greater than that of the block copolymers (made via RAFT polymerisations).

[00298] Table 4D, below, provides similar foamability data (foam height and foam lifetime in seconds) to those above, but instead in respect of statistical and block copolymers fabricated via RAFT polymerisations rather than FRP (standard free radical polymerisation). Since RAFT produces copolymers with lower polydispersities than FRP, this allows polydispersity to be tested as a variable with respect to foamability parameters.

Table 4D - Summary of the foam stabilization performance observed for a library of statistical and block copolymer surfactants prepared by RAFT solution polymerization

[00299] All statistical copolymers presented in Table 4A were synthesized by FRP, and as a result have high dispersities (D = 1.9 - 2.4, see Table 4C). Additional copolymers were prepared using reversible addition-fragmentation chain transfer (RAFT) polymerization to understand the influence of chain length distribution on foam stabilization performance (denoted R-TMHA-stat-PEGA). GPC analysis of RAFT-synthesized copolymers showed significantly lower dispersities than FRP- synthesized copolymers (Table 4C). Foamability assays with RAFT-synthesised copolymers showed similar foamability and foam stability relative to FRP-synthesised copolymers (Table 4D), suggesting that foamability is insensitive to molecular weight distribution. RAFT polymerization also allows copolymer M_n to be controlled, and three R-TMHA-stat-PEGA copolymers were prepared with M_n = 4, 8 or 12 kg mol^-1 by adjusting the comonomer/RAFT agent molar ratio (Table 4C). These copolymers were subjected to the same foaming assay, and all showed comparable foamability and foam stability (Table 4D), with the 4 kg mol^-1 copolymer showing lower foamability at all solvent compositions investigated. Evidently, using RAFT polymerization to improve control over copolymer molecular weight and produce lower dispersity did not enhance performance of TMHA-stat-PEGA copolymers in foam stabilization.

[00300] Diblock copolymer analogues of the most surface-active statistical copolymers (TMHA-PEGA based) were also synthesised using RAFT polymerization (i.e. PTMHA-Wock-PPEGA). Well-defined diblock copolymers with M_n = 11.8 - 12.9 kg mol'¹ and relatively narrow molecular weight distributions (0 = 1 2 - 1 .3), as judged by GPC analysis (Table 4C). PTMHA- Wock-PPEGA copolymers exhibited comparable GPC M_n values as polydisperse statistical copolymers (/W_n = 11 .5 - 13.2 kg mol'¹). Foam stabilization assays with block copolymers in ethanol-water mixtures indicated relatively poor foamability compared to statistical copolymers (Table 4D). Foamability was only observed for PTMHA-Wock-PPEGA forthe most waterrich compositions, while foam heights and lifetimes were significantly lower than those observed for the equivalent statistical copolymer.

EXAMPLE 2 - Polyurethane Foam Stabilisation

[00301] The aforementioned PEGA-TMHA copolymer samples were tested for their ability to stabilise foams produced during a polyurethane synthesis in the presence of a blowing agent (water). Prepolymer mixtures were prepare form Voranol 3322 and Voranol 1447, catalyst DMEA, and surfactant. Specflex NE 112 (isocyanate) was added to begin the blowing reaction, to complete the standard open cell foam formulation. PEGA-stat-TMHA or TEGOstab (a PDMS-PEO copolymer) were used as surfactants. The success of a PU surfactant can be qualitatively assessed by the development of the foam during the reaction. In the absence of surfactant, or with an ineffective surfactant, the growing foam will not be stabilised, leading to low volume and foam collapse (FIG. 8, bottom). However, we observed almost identical performance in the presence of PEGA-TMHA and TEGOstab (PDMS-PEO based copolymer) surfactants during expansion (FIG. 8, top and middle). Notably, the cell structure resulting from PEGA-stat-TMHA stabilised foam differed to the benchmark TEGOstab formulation. We anticipate the modular nature of the inventive copolymer surfactants would allow the foam properties to be easily modified by fine tuning surfactant structural variables such as monomer structures and ratios.

[00302] FIG. 8 shows snapshots from videos taken during PU foaming in the presence of TMHA-PEGA surfactant (top row), a conventional TEGOstab silicone-based surfactant (middle row), and without surfactant (bottom row). Image columns are labelled with time elapsed after adding the pre-polymer mixture to the empty vessel.

EXAMPLE 3 - Copolymer surfactants in firefighting compositions

[00303] The synthetic technology outlined here is applicable to almost any combination of acrylic monomer (or indeed other types of monomer that form a different polymeric backbone), that may be applicable to materials for use in numerous fields. Specific to firefighting foams, the most commonly adopted surfactants are fluorine-based. However, there are health and environmental issues associated with currently adopted small molecule based fluorinate surfactants (e g. perfluorooctanoic acid, PFOA). The inventive copolymer surfactants allow for reduction in fluorine content, introduction of fluorine in a more benign form, or removal of fluorine completely.

[00304] Within firefighting, a foam-based system is used to extinguish flammable liquid fires by providing a blanket of material that sits on top of the liquid, to provide cooling and create a barrier between fuel and ignition source. Thus, the key properties of the foam are low density, and stability in the presence of a range of fuels (e g. alkanes, alcohols). Typically, surfactants used also provide a very low surface energy to aid spreading and prevent mixing with the fuel, hence the application of fluorinated materials. Silicone-based surfactants also represent promising fluorine-free alternatives, due to similarly low surface tension values.

Table 5 - Structure and foamability properties of fluorine and silicone-containing polymers synthesised for the study of firefighting properties

[00305] To test the efficacy of the inventive copolymer surfactants in the context of firefighting foams, we synthesised a new set of fluorine and silicone-containing copolymers, using the same protocols as above. We tested foamability in a range of ethanol-water mixtures as above, reasoning that the ability to foam in mixtures with high ethanol fractions equates to low surface energy surfactants. In addition, foam stability in the presence of alcohol indicates a resistance to alcohol-based fires, which are becoming more commonplace as alcohols replace conventional hydrocarbon solvents. Foamability results are shown in Table 5. [00306] The synthetic technology outlined here is applicable to almost any combination of acrylic monomer (or indeed other types of monomer that form a different polymeric backbone), that may be applicable to materials for use in numerous fields. Specific to firefighting foams, the most commonly adopted surfactants are fluorine-based. However, there are health and environmental issues associated with currently adopted small molecule based fluorinate surfactants (e g. perfluorooctanoic acid, PFOA). The inventive copolymer surfactants allow for reduction in fluorine content, introduction of fluorine in a more benign form, or removal of fluorine completely.

[00307] Within firefighting, a foam-based system is used to extinguish flammable liquid fires by providing a blanket of material that sits on top of the liquid, to provide cooling and create a barrier between fuel and ignition source. Thus, the key properties of the foam are low density, and stability in the presence of a range of fuels (e g. alkanes, alcohols). Typically, surfactants used also provide a very low surface energy to aid spreading and prevent mixing with the fuel, hence the application of fluorinated materials. Silicone-based surfactants also represent promising fluorine-free alternatives, due to similarly low surface tension values.

[00308] In pure ethanol, the fluorinated MAA-HFBMA was the most effective foaming agent. However, in all ethanol-water mixtures tested, MAA-TMSMA copolymers produced the largest foam volumes.

[00309] Foams created by MAA-TMSMA and MAA-HFBMA copolymers were tested for stability in the presence of a model flammable alkane (heptane). A solution of surfactant (1.5 wt%) in a 100 mL measuring cylinder was foamed using an air pump (FIG. 9A-C). The resulting foam was decanted onto a petri dish half-filled with heptane (FIG. 9D). The stability of the foam was then measured as the time taken for complete collapse. Foams stabilised by MAA-HFBMA copolymer floated on top of the heptane and were present for 15 minutes, which is comparable to current firefighting foam formulations. Meanwhile, MAA-TMSMA copolymers collapsed within 8 minutes. Although MAA-stat-HFBMA contains fluorine, it is in a more benign and degradable form than the conventional PFOA surfactants, due to its attachment via a hydrolytically unstable ester. It is envisaged that fluronine-free and silicone-free analogues of the inventive copolymer surfactants would also be applicable in the context of firefighting foams and compositions.

[00310] FIG. 9 shows various stages of foaming for a MAA-HFBMA copolymer solution (1.5 wt%) in 2:1 water: ethanol (by volume) using an air stone pump: (A) the air stone is lowered into solution within a measuring cylinder; (B) after foaming for 5 s, after which the foam filled the volume of the measuring cylinder; (C) 5 min after foaming, where ca. 65% foam volume remained; (D) after applying the foam to a petri dish filled with heptane; (E) 3 min after applying the foam to heptane; (F) demonstration of the solid film forming properties of PMAA-PHFBMA upon drying on a de Nuoy ring 2 min after a ring tensiometry experiment (highlighted by white arrow).

[00311] Another property of firefighting foams is the ability for solidify on top of the flammable liquid to create a barrier against the escape of vapours, and ingress of oxygen. For these purposes, polymeric additives are often included in foaming formulations to precipitate into a solid layer upon exposure to the flammable fuel. We posited that amphiphilic statistical copolymers could serve the dual purpose of foam-stabilising surfactant and solid film forming. It was noted that the PEGA- HFBMA foams created within a measuring cylinder by the air stone pump drained over time, leading to a gel-like foam structure resulting from polymer dried at the struts between bubbles (FIG. 9C). Furthermore, this film forming behaviour readily occurred in films, as observed by the gel-like film which was deposited following a ring tensiometry measurement (FIG. 9E).

[00312] In summary, although the surfactants with properties most amenable to firefighting foams in these initial studies contained fluorine, it is in a potentially more benign and degradable form than in conventional PFOA-type surfactants. We hypothesise that the presence of fluorine as the side chain to a polymer may have fewer detrimental effects on the environment. Further materials optimisation will allow for the reduction or removal of fluorine from copolymer surfactants altogether.

Additional Foamability Data

[00313] Table 5A, below, shows further foamability data (foam height), this time with a diethylene glycol and water solvent system. The formulations in Table 5A are intended as further model firefighting formulations. Table 5A - Foamability of various statistical copolymers (with indicated mass fractions for each monomer) in diethylene glycol / water solvent systems containing the indicated mass fraction of water.

[00314] Diethylene glycol and water were mixed at 50 % w/w, and the copolymers dissolved at 3 % w/w in 1 ml of solvent. 0.1 ml aliquots of water were added and the foamability at each solvent composition measured as described above. High foamability was measured in many of the surfactants (Table 5A), in particular the copolymers with higher fractions of the hydrophilic monomers. Foams generated in this manner were transferred onto heptane to test their stability against model fuels and showed lifetimes of > 20 mins. In addition, foams generated by TMHMA-stat-GMA copolymers solidified on top of the solvent as they dried out. Such film-forming behaviour would be advantageous in firefighting foam formulations.

EXAMPLE 4 - Understanding Foam Stabilisation Mechanism through Tensiometric Analysis of Surfactant Solutions

[00315] In orderto quantify the surface tension reduction of ethanol-water mixtures achieved by these inventive copolymer surfactants, bubble pressure tensiometry was conducted. Interfacial properties of six PEGA-TMHA, which had variable M_n and D (see FIG. 10D). A copolymer stock solution was prepared in 50% ethanol (by volume) and sequentially added in increasing volumes to a vessel of 50% ethanol, and tensiometric analysis performed at each concentration. This lower ethanol solvent composition was initially chosen to overcome instrumental limitations: the capillaries used for creating the bubble were designed for aqueous solutions, and high concentrations of polar organic solvents in the mixture affects the wetting behaviour and can lead to systematic errors. For each sample, surface tension was measured as a function of surface age from 10 to 1000 ms (see FIG. 10A for example plot).

[00316] The tensiometry data for all copolymers at multiple concentrations showed no sign of reaching an equilibrium surface tension value at increasing surface ages > 1 s (FIG. 10A), which is contrary to the expected behaviour for this type of surface tension analysis. However, this may be due to the fact that equilibrium surface tension could not be achieved within 1000 ms, which was a limitation of the equipment used. Further concentration-dependent surface tension data were collected for copolymers in a 60% ethanol (by volume) solution, to better portray the composition of the final sanitiser product (FIG. 10B). In most cases, tensiometry measurements displayed the expected trend of decreasing surface tension with increasing surfactant concentration. Data in FIG. 10B shows the lowest M_n copolymer (C) reduced the surface tension most significantly, (from pure solvent value of 27.92 mN nr¹ to 27.47 mN nr¹). Higher M_n copolymers reduced the surface tension to a lesser extend (e g., F, 27.84 mN nr¹). These data therefore correlate with the foaming data, where a shorter chain length lead to more effective foaming under equivalent conditions. Hence, the hypothesis that M_n, and by extension copolymer chain length, are pertinent factors in foamability is reinforced by the tensiometry data presented here.

[00317] FIG. 10 shows (A) Example of bubble pressure tensiometry data for 50% ethanol (solid line) and in the presence of multiple concentrations of surfactant C (increasing concentration with greyscale). (B) Concentration dependence of surface tension measured at a surface age of 1 s for copolymers C-F in 60% ethanol. Data from (B) was used to calculate diffusion constants using Equation 3, which are plotted for A-F as a function of concentration in (C). (D) Table describing characteristics of copolymer surfactants A-F, where y_min values were recorded at 50% ethanol for A & B, 60% ethanol for C- F.

[00318] Additional information can be extracted from the data by the calculation of diffusion constants, which can be derived from Equation 3:

where D is diffusion constant, is time, is surface tension, C is surfactant concentration, is gas constant, Tis temperature.

[00319] This equation holds valid for short timescales of kinetic surface tension data and the resulting diffusion constants give insight into the relative molecular mobilities of each surfactant in solution at varying concentrations. Plots of diffusion constant as a function of concentration for copolymers A-F (FIG. 10C), showed very similar magnitudes and trends for each surfactant, with diffusion constants decreasing with increasing concentration. This contrasts what is usually observed for non-ionic surfactants, which tend to show invariant diffusion constants as a function of concentration at conditions above their critical micellar concentration (CMC). This discrepancy in behaviours may be attributed to the differences in selfassembly between a ‘typical’ surfactant and a statistical copolymer surfactant. The morphology of amphiphilic statistical copolymers in selective solvents have previously been studied using small-angle X-ray scattering (SAXS) analysis, which were conducted here to further understanding of the structure of these copolymer surfactants within the foaming solvent.

Further Surface Tensiometry Data

[00320] FIG. 12 shows: A) variation of interfacial tension at the solvent-air interface with different ethanol-water mixtures (ethanol mass fractions provided) containing fixed concentrations (5 g/dm³) of each of TMHA-stat-PEGA and PTMHA-b/ock-PPEGA copolymers; B) variation of interfacial tension at the solvent-air interface with different concentrations (0.1-5 g/dm³) of TMHA-stat-PEGA and PTMHA-b/ock-PPEGA copolymers present at different concentrations in ethanol/water (61.2% w/w ethanol); and C) variation of interfacial tension at the solvent-air interface with different ethanol-water mixtures (ethanol mass fractions provided) containing a fixed concentration (5 g/dm³) of TMHMA-stat-PEGMA, a methacrylic analogue of TMHA-stat-PEGA that has a significantly higher glass transition temperature (7g).

[00321] Foamability assays showed that several statistical copolymer surfactants stabilize foams in low surface energy solvents (< 29 mN nr¹), in which analogous diblock copolymers did not perform effectively. This observation suggests that these hydrocarbon-based statistical copolymer surfactants are more surface-active, and ring tensiometry was used to compare the reduction in interfacial tension between TMHA-stat-PEGA and PTMHA-b/ock-PPEGA in various ethanol-water mixtures (Figure 12A and 12B). Copolymer stock solutions (5.0 g dm^-3) were prepared in ethanol and was determined in various ethanol-water mixtures after serial dilution with water, to replicate the foaming assay.

[00322] At the highest ethanol fractions (79 - 100% w/w), was only marginally lowered relative to the solvent for each copolymer (Figure 12A), consistent with the absence of foam at such solvent compositions. However at 57% w/w ethanol (for which 26.21 ± 0.03 mNnr¹), the statistical copolymer lowered the surface tension to 24.56 ± 0.01 mNm'¹, whereas the diblock copolymer only affected a reduction to 25.26 ± 0.03 mN nr¹. This observation is consistent with the foaming assay: in which only the statistical copolymer produced a stable foam at this ethanol-water composition. The difference in between the statistical and diblock copolymers gradually increased on addition of further water. At 44% w/w ethanol (not studied in the foamability assay), PTMHAos-block-PPEGA produced the same as that for the pure solvent mixture (ca. 28.2 mN nr¹), which implies that copolymer chains no longer occupied the interface at those conditions.

[00323] Surface tensiometry was also measured for copolymer concentrations of 0.1 - 5.0 g dm^-3 to identify the critical micellar concentrations (CMC) in ethanol-water composition containing 61.2% w/w ethanol (Figure 1 B). The diblock copolymer reduced between 2.7 and 5.0 g dm^-3, but at lower copolymer concentrations was equal to the pure solvent mixture. These two distinct regimes suggest that the diblock copolymer exhibits a CMC at < 2.7 g dm'³. Above this concentration the solvent-air interface should be saturated with copolymer chains, with micelles present in the bulk solution. The statistical copolymer reduced by ca. 0.1 - 0.2 mN nr¹ more than the diblock copolymer at every concentration investigated, and was surface active down to 0.1 g dm^-3, and exhibited no CMC overthis concentration range.

[00324] Surface tensiometry data were also obtained for TMHMA-stat-PEGMA, a methacrylic analogue of TMHA-stat- PEGA that has a significantly higher glass transition temperature (T_g). Surface tensiometry measurements showed that TMHMA-stat-PEGMA does not significantly reduce the surface tension for a range of ethanol-water mixtures (Figure 12C). Nevertheless, TMHMA-stat-PEGMA copolymers were still able to stabilize foams at higher water contents, although foamability and foam stability were much lower than those obtained for the analogous TMHA-stat-PEGA copolymers (Table 4A). We hypothesize that TMHMA-stat-PEGMA chains can only occupy the interface when subjected to a significant amount of energy (i.e. vortex mixing) to drive the transition from collapsed unimolecular micelles to open conformations at the interface. As the methacrylic backbone is relatively inflexible, this transition cannot occur under the static conditions used in tensiometry. Thus, chain mobility - for which the copolymer T_g is a proxy - is also a potentially important parameter affecting the performance of statistical copolymer surfactants. This is further reflected in 'OOA-stat-PEGA, another high T_g copolymer, which is also a much less effective foam stabilizer than TMHA-stat-PEGA.

EXAMPLE 5 - Understanding Foam Stabilisation Mechanism through SAXS analysis of foaming solutions

[00325] Conventional surfactants tend to self-assemble, in any given selective solvent, into nanoparticles that most commonly have a spherical, worm-like, and vesicular morphology. In water, such aggregation is induced by a combination of entropic and enthalpic effects, particularly minimising the contact between water and hydrophobic components, and to prevent the unfavourable structuring of water around hydrophobic groups. However, surfactant molecules usually consist of a single region of solvophobic character and a single region of solvophilic character, either in small molecules (e g. sodium oleate, sodium dodecyl sulfonate) or block copolymers (e g. Pluronics). However, due to the statistical, random, or alternating distribution of solvophobic and solvophilic moieties along the polymer chain of the aforementioned copolymer surfactants, the same assumptions cannot be made about the aggregation behaviour. Indeed, previous studies into the amphiphilic statistical copolymer phase behaviour in solution have unveiled unusual self-assembly behaviour, in which individual polymer chains fold into micelles with very low aggregation number (N_agg = 1-5), in contrast to the larger assemblies in conventional surfactants (N_agg > 50).

[00326] In order to better understand the mechanism of foam stabilisation for these surfactants in alcohol-water mixtures, we sought to characterise their aggregation behaviour using SAXS. SAXS is commonly used to study self-assembly of surfactants in selected solvents, since it allows in situ analysis of particle size and shape above the CMC. In this study, foaming solutions were prepared from a range of different polymeric surfactants to determine whether they were soluble in the solvent, or existed in some colloidal state (i.e. particles), and whether this was related to foaming efficacy. Six surfactants with a range of different foaming efficacies (from Table 2) were studied by SAXS in a 2:1 ethanol/water mixture (w/w), specifically PEGA-TMHA (at two different HLB), PEGMA-TMHA, PEGA-LA, PEGA-iOA, PEGA-EHA (see Figure 11 B and Table 6).

Table 6 - Results of SAXS Analysis

[00327] The presence of a dilute dispersion of particles in solution (e g. surfactant aggregates) is characterised by the appearance of intensity minima in the SAXS pattern arising from the form factor contribution to scattering. The position of these minima along the q axis is related to the size of the objects, whilst information about the shape of the particles can be derived from the gradient of the line at low q. Four of the surfactants (PEGA-TMHA, PEGA-LA, PEGA-EHA, and PEGA-iOA) displayed well-defined minima indicative of particles dispersed within the solvent (FIG. 11 A). The q-position of the minima varied between surfactants, but very similar values were obtained for PEGA-TMHA, PEGA-iOA, and PEGA-EHA (q_min = 0.137 - 0.0.157 A’¹), indicative of similarly sized particles (radii between 2.9 - 3.3 nm, see Table 6). Meanwhile, PEGA-LA displayed much larger particles with average radii of 4.8 nm. The particle size appeared to correlate well with the length of the solvophobic side chain, i.e. lauryl > iso-octyl > trimethylhexyl/ethylhexyl. The very small size of the particles observed is a strong indication of single-molecule micelles, i.e. polymer chains that have folded in a way that solvophobic groups are located in the core, and solvophilic groups populate the surface acting as the “shell” of the particle (FIG. 11 C). Due to the low electron density contrast between the particle shell and the solvent, the scattering arises from only the micellar core. Characterisation of the shell morphology and thickness is beyond the scope of this study.

[00328] The self-assembly behaviour of these polymeric surfactants is in contrast to conventional surfactants, where multiple molecules aggregate together into nanoparticles in which all solvophobic and solvophilic groups form the shell and core, respectively (FIG. 5). In solvents containing conventional surfactants, foam can only be stabilised by dissociation of molecules from the aggregates followed by population at the solvent-air interface, where solvophobic groups are oriented towards the gas and solvophilic groups are anchored to the solvent surface. However, from micelles that contain a single polymer chain, the mechanism of foam stabilisation must be entirely different. We propose a mechanism by which the polymer backbone unfolds from a collapsed state in the solvent to a more stretched state at the interface. This rearrangement allows the solvophobic groups that were located at the micellar core, which have lower surface energy, to populate the interface. This mechanism is related to the way in which foams are created in nature, in which protein molecules that are globular in solution unfold under mechanically stimulation (i.e. the “whipping” mechanism performed by tree frogs) to expose hydrophobic amino acids and stabilise the solvent-air interface. However, this mechanism of foam stabilisation has not been reported in synthetic systems.

[00329] Changing the HLB of the copolymer chains by increasing the PEGA content in PEGA-stat-TMHA resulted in very different behaviour in the ethanol/water solvent mixture. Relative to the symmetrical PEGA-stat-TMHA copolymer, the scattering minimum for the PEGA-rich copolymer was much broader and appeared at higher q_min (0.198 A'¹). This indicated smaller and more ill-defined particles, which could be better described as dissolved polymer chains rather than single molecule micelles. The higher PEGA content is likely to increase the solubility in an alcohol-rich solvent, therefore the driving force for copolymer chains to fold and collapse is lower. Notably, the foamability from this surfactant was lower than the symmetrical PEGA-TMHA, which strongly suggests the unimolecular micellar state is a key precursor to foam stabilisation. Copolymer chains that are stretched at the interface will experience an additional energetic barrier to the reverse process (i.e. re-dispersing in the solvent), since the chains must change conformation and reorient. This energetic barrier could explain the longer foam lifetime observed for the micelle-forming copolymers relative to the soluble copolymers.

[00330] FIG. 11 shows (A) stacked SAXS plots (subtracted) for a number of statistical copolymer surfactants in an ethanol/water mixture (2/1 by mass). (B) The copolymer compositions are listed in order (top to bottom) in the table, alongside the measured scattering minima and radius of dispersed nanoparticles. The very small radii of the micelles is indicative of single molecule micelles or micelles with very low aggregation numbers. (C) A schematic diagram showing the proposed mechanism by which copolymer surfactants change conformation at the interface to stabilise foam formation.

[00331] The polymer architecture also played a significant role in structure within the solvent. PEGMA-grad-TMHA showed no evidence of single molecule micelles according to SAXS analysis. Indeed, the mixture was cloudy in appearance, suggesting the presence of aggregates on the order of magnitude to scatter light (i.e. >100 nm). The absence of a well- defined form factor minimum within the q-range studied indicated supported this hypothesis, and led us to believe particles consisted of multiple polymer molecules. The lower foamability of PEGMA-grad-TMHA relative to PEGMA-stat-TMHA further indicates that the unimolecular micellar state is key to the foaming mechanism in these copolymer surfactants.

[00332] Overall, morphological data obtained from SAXS analysis outlines the importance of self-assembly on foamability in ethanol/water mixtures. Surfactants which fold into single molecule micelles appear to adopt a unique mechanism of foam stabilisation which helps to drive high foamability. However, solvophobic monomer structure also appears to be a governing factor, since surfactants with similar particle structures showed vastly different foamability. In particular, it appeared that the degree of branching within the solvophobic side chain is important. We postulated that a greater degree of branching within the side chain would lead to a lower surface energy. Indeed, preliminary surface tension measurements using ring tensiometry demonstrated y as low as 24.4 mNnr¹ for a symmetrical PEGA-TMHA copolymer in an alcohol/water mixture (2/1 by volume), comparable with the fluorinated copolymer MAA-HFBMA (23.2 mNirr¹).

CONCLUSIONS

[00333] The copolymer surfactants described herein, synthesised by simple and commercially applicable techniques, allow foaming in alcohol and alcohol-water mixtures that is usually difficult to achieve. Many of these surfactants were also able to readily foam in pure water. After identifying some of the more effective hydrophobic and hydrophilic monomers, it was demonstrated that foaming can be optimised for ethanol-water mixtures applicable to hand sanitisation by designing the surfactant structure and formulation. The surfactants were also demonstrated to have superior barrier properties on a model skin membrane, indicating the potential for enhancing the moisturising properties of hand sanitiser formulations. The copolymer surfactants also enable the stabilisation of foam expansion in polyurethane foam synthesis, and surfactant design could allow for fine tuning of the material properties. Finally, incorporating fluorine and silicone-containing groups into the copolymer surfactants imparts properties amenable to firefighting foams that could replace the current highly toxic chemicals used therein. Exploration of the mechanism of foam stabilisation using tensiometry and SAXS indicated that a unique mechanism governs the foamability, driven by the unfolding of single molecule micelles at the liquid-air interface.

NUMBERED PARAGRAPHS

The present invention and/or embodiments thereof are further described by way of the following numbered paragraphs:

1 . A foamable composition comprising: one or more foamable components; and a copolymer compound of Formula Ila: poly(M₁-stat-M₂), wherein M₁ is or is derived from a solvophobic monomer comprising a solvophobic pendent group, R_{1 :} wherein M₁ has a logP value greater than 1 .5, and M₂ is or is derived from a solvophiilic monomer comprising a solvophiilic pendent group, R₂, wherein M₂ has a logP value less than 1 .5; wherein the copolymer compound optionally comprises further monomers, M_n, on the proviso that monomers M₁ and M₂ constitute at least 70% of the monomer units of the copolymer compound.

2. The foamable composition of paragraph 1 , wherein M₁ has a logP value of at least 2.0 and M₂ has a logP value of less than 1 .

3. The foamable composition of paragraph 1 , wherein M₁ has a logP value of at least 3.0 and M₂ has a logP value of less than 0.5.

4. The foamable composition of paragraph 1 or 2, wherein the foamable composition is selected from the group consisting of a hand-sanitizer composition, a firefighting composition, a foamable polymeric composition (e g. foamable polyurethane composition), and a foamable polymerizable composition (e g. a foamable composition comprising at least one monomer for forming a foamable polyurethane).

5. The foamable composition of paragraph 4, wherein the foamable composition is a hand-sanitizer comprising: the copolymer compound; and a solvent system comprising water and a (1 -4C)alcohol in a weight ratio of between 3:7 and 7:3; wherein the composition comprises 50-75 wt% (1 -4C)alcohol.

6. The foamable composition of paragraph 5, wherein: M₁ comprises pendent groups (RT) comprising a continuous carbon chain comprising at least 5 carbon atoms, one or more branched hydrocarbyl moieties, and at least one methyl (CH₃) group; and M₂ comprises pendent groups (R₂) that are free of any methyl groups, with the optional exception of a single terminal methyl group attached to a heteroatom, and have a chain length of at least 3, suitably at least 5, suitably at least 7, comprising two or more hetero atoms.

7. The foamable composition of paragraph 4, wherein the foamable composition is a firefighting composition (e g. a firefighting concentrate composition or foamable firefighting composition formed from the firefighting concentrate composition).

8. The foamable composition of paragraph 7, wherein the firefighting composition further comprises a corrosion inhibitor.

9. The foamable composition of paragraph 6 or 7, wherein the firefighting composition further comprises a water- soluble polymer that precipitates or forms a gel upon contact with a water-miscible flammable organic solvent, wherein suitably the polymer is a polysaccharide.

10. The foamable composition of any of paragraphs 6 to 8, wherein RT of the copolymer compound comprises: a (perfluorocarbon group that is part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide, suitably wherein the copolymer compound is otherwise free of fluorine atoms; and I or a siloxane (suitably methyl siloxane moiety or perfluoromethyl siloxane moiety) group that is part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide, suitably wherein the copolymer compound is otherwise free of silicon atoms.

11. The foamable composition of paragraph 4, wherein the foamable composition is a polymeric foam kit (kit of parts for producing a polymeric foam) comprising: a) either: i. a foamable polymer; or ii. polymerizable monomers for forming the foamable polymer, wherein the polymerizable monomers comprise a first polymerizable monomer and a second polymerizable monomer; b) a blowing agent (e.g. water); c) the copolymer compound; and d) optionally one or more additives (e g. a polymerisation catalyst); wherein optionally the kit comprises a blowing agent composition that comprises both the blowing agent and the copolymer compound; wherein optionally the kit comprises a surfactant-containing monomer composition comprising a polymerizable monomer and the copolymer compound.

12. The foamable composition of paragraph 4, wherein the foamable composition is a foamable polymerizable composition comprising: the copolymer compound; a first polymerizable monomer for forming a foamable polymer (e g. a polyurethane); and optionally: a second polymerizable monomer for forming the foamable polymer; a blowing agent (e.g. water); and/or one or more additives. 13. The foamable composition of paragraph 11 or 12, wherein the foamable polymer is a polyurethane, formable by polymerising the first polymerizable monomer with the second polymerizable monomer, wherein: the first polymerizable monomer is or comprises one or more polyols; and the second polymerizable monomer is or comprises one or more polyisocyanates.

14. The foamable composition of paragraph 4, wherein the foamable composition is a blowing agent composition for forming a polymeric foam from the polymeric foam kit of paragraph 11 or 13 or from the foamable polymerizable composition of paragraph 12, the composition comprising: a blowing agent, suitably water; and the copolymer compound.

15. The foamable composition of any of paragraphs 11 to 14, wherein: M₁ comprises pendent groups (RT) comprising a continuous carbon chain comprising at least 3 carbon atoms, one or more branched hydrocarbyl moieties, and at least one methyl (CH₃) or perfluoromethyl group; and

M₂ comprises pendent groups (R₂) having a chain length of at least 3, suitably at least 5, suitably at least 7, comprising two or more hetero atoms, that are free of any methyl groups, with the optional exception of a single terminal methyl group attached to a heteroatom; wherein: wherever the copolymer compound comprises a (perfluorocarbon group, said (per)fluorocarbon group is part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide, suitably wherein the copolymer compound is otherwise free of fluorine atoms; and wherever the copolymer compound comprises a siloxane (suitably methyl siloxane moiety or perfluoromethyl siloxane moiety) group, said group is part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide, suitably wherein the copolymer compound is otherwise free of silicon atoms.

16. A foam dispenser for dispensing a foamable composition (or foamed form thereof) as described in any preceding paragraph, wherein the foam dispenser contains or is fluidly connected to one or more reservoirs containing: the one or more foamable components; and the copolymer compound; wherein the foam dispenser is configured or operable to dispense the foamable composition (or a foamed form thereof, for instance by causing foaming prior to or during dispensation), suitably via a dispensing nozzle; wherein the foamable component(s) and copolymer compound may be contained separately within the foam dispenser or reservoir(s) fluidly connected thereto and/or in one or more suitable mixtures of any combination thereof.

17. The foam dispenser of paragraph 14, wherein the foam dispenser is a hand-sanitizer dispenser containing the hand-sanitizer of paragraphs 5 or 6.

18. The foam dispenser of paragraph 16, wherein the foam dispenser is a firefighting apparatus (e g. fire-extinguisher, firefighting assembly optionally connected or connectable to a fire engine or fire hydrant) containing the firefighting composition of any of paragraphs 7 to 10.

19. The foam dispenser of paragraph 14, wherein the foam dispenser is a polymeric foam dispenser, suitably a polyurethane foam dispenser, containing the foamable composition of any of paragraphs 9 to 13.

20. A method of generating or forming a foamed composition (or foam), the method comprising foaming the foamable composition of any of paragraphs 1 to 15, optionally via a foam dispenser of any of paragraphs 16 to 19. 21 . The method of paragraph 20, wherein the foamable composition is the hand-sanitizer of paragraphs 5 or 6, and foaming is caused by introducing air into the foamable composition, suitably as the foamable composition is dispensed from the foam dispenser of paragraph 17.

22. The method of paragraph 20, wherein the foamable composition is the firefighting composition of any of paragraphs 7 to 10, and foaming is caused by primary aspiration, suitably before or during the firefighting composition being dispensed from the foam dispenser of paragraph 18.

23. The method of paragraph 20, wherein the foamable composition is the firefighting composition of any of paragraphs 7 to 10, and foaming is caused by secondary aspiration, suitably during or after the firefighting composition is dispensed from the foam dispenser of paragraph 18.

24. The method of paragraph 22 or 23, wherein the firefighting composition of any of paragraphs 7 to 10 is a firefighting concentrate composition, and the method comprises diluting the firefighting concentration composition (suitably with water) to form a foamable firefighting composition (which, after dilution, suitably comprises 0.5-10 vol% firefighting concentrate composition), and foaming the foamable firefighting composition.

25. The method of paragraph 20, wherein the foamable composition is the foamable composition of any of paragraphs 11 to 15, and foaming is caused by contacting the foamable polymer (during its formation) with the blowing agent and copolymer compound; wherein, optionally, the copolymer compound is pre-mixed with the blowing agent as part of a blowing agent composition comprising the blowing agent and copolymer compound; wherein, optionally, the copolymer compound is pre-mixed with a polymerizable monomer(s) as part of a surfactantcontaining monomer composition comprising the copolymer compound and the polymerizable monomer(s).

26. A foamed composition obtained by the method of any of paragraphs 20 to 25.

27. A foamed composition, comprising and/or formed by foaming the foamable composition of any of paragraphs 1 to 15.

28. A foamed composition, comprising a foam comprising the copolymer compound as defined in any of paragraphs 1 to 15.

29. The foamed composition of any of paragraphs 26 to 28, wherein the foamed composition is a hand-sanitizer foam.

30. The foamed composition of any of paragraphs 26 to 28, wherein the foamed composition is a firefighting foam.

31. The foamed composition of any of paragraphs 26 to 28, wherein the foamed composition is a polymeric foam, suitably a polyurethane foam.

32. The foamable composition of any of paragraphs 1 to 15, the foam dispenser of any of paragraphs 16 to 19, the method of any of paragraphs 20 to 25, the foamed composition of any of paragraphs 26 to 31 , or any preceding paragraph dependent thereon, wherein the copolymer compound has an HLB value between 6.5 and 13.5.

33. The foamable composition of any of paragraphs 1 to 15, the foam dispenser of any of paragraphs 16 to 19, the method of any of paragraphs 20 to 25, the foamed composition of any of paragraphs 26 to 31 , or any preceding paragraph dependent thereon, wherein the weight ratio of M₁ to M₂ in the copolymer compound is between 3:1 and 1 :3, more suitably between 2:1 and 1 :2.

34. The foamable composition of any of paragraphs 1 to 15, the foam dispenser of any of paragraphs 16 to 19, the method of any of paragraphs 20 to 25, the foamed composition of any of paragraphs 26 to 31 , or any preceding paragraph dependent thereon, wherein the mass fraction of M₁ in the copolymer compound is 0.25 to 0.75 whilst the mass fraction of M₂ in the copolymer compound is 0.75 to 0.25, wherein the sum of mass fractions for M₁ and M₂ total 1 .

35. The foamable composition of any of paragraphs 1 to 15, the foam dispenser of any of paragraphs 16 to 19, the method of any of paragraphs 20 to 25, the foamed composition of any of paragraphs 26 to 31 , or any preceding paragraph dependent thereon, wherein the copolymer compound has a homogeneous polyacrylic backbone, a homogeneous polyalkylacrylic backbone, a homogeneous polyacrylamide backbone, or a homogeneous polymethacrylamide backbone.

36. The foamable composition of any of paragraphs 1 to 15, the foam dispenser of any of paragraphs 16 to 19, the method of any of paragraphs 20 to 25, the foamed composition of any of paragraphs 26 to 31 , or any preceding paragraph dependent thereon, wherein: M₁ is a monomer having the formula M_1A:

wherein R_B1 is either H or a (1 -2C)alkyl (e g. methyl), XT is O or NH, and RT is a pendent solvophobic group as defined in any preceding paragraph;

M₂ is a monomer having the formula M_2t:

wherein R_B2 is either H or a (1 -2C)alkyl (e g. methyl), X₂ is O or NH, and R₂ is a pendent solvophilic group as defined in any preceding paragraph.

37. The foamable composition, the foam dispenser, the method, or the foamed composition, of paragraph 36, wherein R_B1 is H or CH₃, XT is O, R_B2 is H or CH₃, and X₂ is O.

38. The foamable composition of any of paragraphs 1 to 15, the foam dispenser of any of paragraphs 16 to 19, the method of any of paragraphs 20 to 25, the foamed composition of any of paragraphs 26 to 31 , or any preceding paragraph dependent thereon, wherein: wherever the copolymer compound comprises a (perfluorocarbon group, said (per)fluorocarbon group is part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide, suitably wherein the copolymer compound is otherwise free of fluorine atoms; and wherever the copolymer compound comprises a siloxane (suitably methyl siloxane moiety or perfluoromethyl siloxane moiety) group, said group is part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide, suitably wherein the copolymer compound is otherwise free of silicon atoms.

39. The foamable composition of any of paragraphs 1 to 15, the foam dispenser of any of paragraphs 16 to 19, the method of any of paragraphs 20 to 25, the foamed composition of any of paragraphs 26 to 31 , or any preceding paragraph dependent thereon, wherein RT comprises a continuous carbon chain comprising at least 3 carbon atoms and at least one methyl group (or perfluoromethyl group).

40. The foamable composition of any of paragraphs 1 to 15, the foam dispenser of any of paragraphs 16 to 19, the method of any of paragraphs 20 to 25, the foamed composition of any of paragraphs 26 to 31 , or any preceding paragraph dependent thereon, wherein R₂ is either H or a group that is free of any methyl groups (or perfluoromethyl groups), with the optional exception of a single terminal methyl group attached to a heteroatom, free of any continuous carbon chains comprising 3 or more carbon atoms, and comprises one or more heteroatoms (preferably one or more oxygen atoms)

41. The foamable composition of any of paragraphs 1 to 15, the foam dispenser of any of paragraphs 16 to 19, the method of any of paragraphs 20 to 25, the foamed composition of any of paragraphs 26 to 31 , or any preceding paragraph dependent thereon, wherein R₂ comprises at least one heteroatom (e g. O or N, preferably O, such as OH, ester, or ether moieties), suitably at least two heteroatoms, more suitably at least three heteroatoms, most suitably at least four heteroatoms, suitably wherein R₂ has a chain length of at least 3, suitably at least 5, suitably at least 7. 42. The foamable composition of any of paragraphs 1 to 15, the foam dispenser of any of paragraphs 16 to 19, the method of any of paragraphs 20 to 25, the foamed composition of any of paragraphs 26 to 31 , or any preceding paragraph dependent thereon, wherein the copolymer compound is selected from the group consisting of:

• A copolymer compound of Formula poly(PEGA-stat-EHA).

• A copolymer compound of Formula poly(PEGA-stat-EHMA).

• A copolymer compound of Formula poly(PEGA-stat-TMHA).

• A copolymer compound of Formula poly(PEGMA-stat-TMHA).

• A copolymer compound of Formula poly(PEGMA-stat-TMHMA).

• A copolymer compound of Formula poly(PEGA-stat-iOA). .

• A copolymer compound of Formula poly(GMA-stat-TMHA).

• A copolymer compound of Formula poly(AA-stat-TMHA).

• A copolymer compound of Formula poly(PEGMA-stat-TMSMA).

• A copolymer compound of Formula poly(MAA-stat-TMSMA).

• A copolymer compound of Formula poly(MAA-stat-HFBMA).

• A copolymer compound of Formula poly(PEGMA-stat-HFBMA).

• A copolymer compound of Formula poly(PEGA-stat-LA).

43. The foamable composition of any of paragraphs 1 to 15, the foam dispenser of any of paragraphs 16 to 19, the method of any of paragraphs 20 to 25, the foamed composition of any of paragraphs 26 to 31 , or any preceding paragraph dependent thereon, wherein the copolymer compound is poly(PEGA-stat-TMHA).

Claims

1 . A composition comprising: one or more foamable components; and a copolymer compound of Formula Ila: poly(M₁-stat-M₂), wherein M₁ is or is derived from a solvophobic monomer comprising a solvophobic pendent group, R_{1 :} wherein M₁ has a logP value greater than 1 .5, and M₂ is or is derived from a solvophiilic monomer comprising a solvophiilic pendent group, R₂, wherein M₂ has a logP value less than 1 .5; wherein the copolymer compound optionally comprises further monomers, M_n, on the proviso that monomers M₁ and M₂ constitute at least 70% of the monomer units of the copolymer compound.

2. The composition of claim 1 , wherein M₁ has a logP value of at least 2.0 and M₂ has a logP value of less than 1 .

3. The composition of claim 1 , wherein M₁ has a logP value of at least 3.0 and M₂ has a logP value of less than 0.5.

4. The composition of claim 1 or 2, wherein the composition is selected from the group consisting of a hand-sanitizer composition, a firefighting composition, a foamable polymeric composition (e g. foamable polyurethane composition), and a foamable polymerizable composition (e g. a composition comprising at least one monomer for forming a foamable polyurethane).

5. The composition of claim 4, wherein the composition is a hand-sanitizer comprising: the copolymer compound; and a solvent system comprising water and a (1 -4C)alcohol in a weight ratio of between 3:7 and 7:3; wherein the composition comprises 50-75 wt% (1 -4C)alcohol.

6. The composition of claim 5, wherein: M₁ comprises pendent groups (RT) comprising a continuous carbon chain comprising at least 5 carbon atoms, one or more branched hydrocarbyl moieties, and at least one methyl (CH₃) group; and

M₂ comprises pendent groups (R₂) that are free of any methyl groups, with the optional exception of a single terminal methyl group attached to a heteroatom, and have a chain length of at least 3, suitably at least 5, suitably at least 7, comprising two or more hetero atoms.

7. The composition of claim 4, wherein the composition is a firefighting composition (e g. a firefighting concentrate composition or foamable firefighting composition formed from the firefighting concentrate composition).

8. The composition of claim 7, wherein the firefighting composition further comprises a corrosion inhibitor.

9. The composition of claim 6 or 7, wherein the firefighting composition further comprises a water-soluble polymer that precipitates or forms a gel upon contact with a water-miscible flammable organic solvent, wherein suitably the polymer is a polysaccharide.

10. The composition of any of claims 6 to 8, wherein RT of the copolymer compound comprises: a (perfluorocarbon group that is part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide, suitably wherein the copolymer compound is otherwise free of fluorine atoms; and I or a siloxane (suitably methyl siloxane moiety or perfluoromethyl siloxane moiety) group that is part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide, suitably wherein the copolymer compound is otherwise free of silicon atoms.

11 . The composition of claim 4, wherein the composition is a polymeric foam kit (kit of parts for producing a polymeric foam) comprising: e) either: iii. a foamable polymer; or iv. polymerizable monomers for forming the foamable polymer, wherein the polymerizable monomers comprise a first polymerizable monomer and a second polymerizable monomer; f) a blowing agent (e.g. water); g) the copolymer compound; and h) optionally one or more additives (e g. a polymerisation catalyst); wherein optionally the kit comprises a blowing agent composition that comprises both the blowing agent and the copolymer compound; wherein optionally the kit comprises a surfactant-containing monomer composition comprising a polymerizable monomer and the copolymer compound.

12. The composition of claim 4, wherein the composition is a foamable polymerizable composition comprising: the copolymer compound; a first polymerizable monomer for forming a foamable polymer (e g. a polyurethane); and optionally: a second polymerizable monomer for forming the foamable polymer; a blowing agent (e.g. water); and/or one or more additives.

13. The composition of claim 11 or 12, wherein the foamable polymer is a polyurethane, formable by polymerising the first polymerizable monomer with the second polymerizable monomer, wherein: the first polymerizable monomer is or comprises one or more polyols; and the second polymerizable monomer is or comprises one or more polyisocyanates.

14. The composition of claim 4, wherein the composition is a blowing agent composition for forming a polymeric foam from the polymeric foam kit of claim 11 or 13 or from the foamable polymerizable composition of claim 12, the composition comprising: a blowing agent, suitably water; and the copolymer compound.

15. The composition of any of claims 11 to 14, wherein: M₁ comprises pendent groups (RT) comprising a continuous carbon chain comprising at least 3 carbon atoms, one or more branched hydrocarbyl moieties, and at least one methyl (CH₃) or perfluoromethyl group; and

16. A foam dispenser for dispensing a composition (or foamed form thereof) as claimed in any preceding claim, wherein the foam dispenser contains or is fluidly connected to one or more reservoirs containing: the one or more foamable components; and the copolymer compound; wherein the foam dispenser is configured or operable to dispense the composition (or a foamed form thereof, for instance by causing foaming prior to or during dispensation), suitably via a dispensing nozzle; wherein the foamable component(s) and copolymer compound may be contained separately within the foam dispenser or reservoir(s) fluidly connected thereto and/or in one or more suitable mixtures of any combination thereof.

17. The foam dispenser of claim 16, wherein the foam dispenser is a hand-sanitizer dispenser containing the handsanitizer of claims 5 or 6.

18. The foam dispenser of claim 16, wherein the foam dispenser is a firefighting apparatus (e g. fire-extinguisher, firefighting assembly optionally connected or connectable to a fire engine or fire hydrant) containing the firefighting composition of any of claims 7 to 10.

19. The foam dispenser of claim 16, wherein the foam dispenser is a polymeric foam dispenser, suitably a polyurethane foam dispenser, containing the composition of any of claims 9 to 13.

20. A method of generating or forming a foamed composition (or foam), the method comprising foaming the composition of any of claims 1 to 15, optionally via a foam dispenser of any of claims 16 to 19.

21 . The method of claim 20, wherein the composition is the hand-sanitizer of claims 5 or 6, and foaming is caused by introducing air into the composition, suitably as the composition is dispensed from the foam dispenser of claim 17.

22. The method of claim 20, wherein the composition is the firefighting composition of any of claims 7 to 10, and foaming is caused by primary aspiration, suitably before or during the firefighting composition being dispensed from the foam dispenser of claim 18.

23. The method of claim 20, wherein the composition is the firefighting composition of any of claims 7 to 10, and foaming is caused by secondary aspiration, suitably during or after the firefighting composition is dispensed from the foam dispenser of claim 18.

24. The method of claim 22 or 23, wherein the firefighting composition of any of claims 7 to 10 is a firefighting concentrate composition, and the method comprises diluting the firefighting concentration composition (suitably with water) to form a foamable firefighting composition (which, after dilution, suitably comprises 0.5-10 vol% firefighting concentrate composition), and foaming the foamable firefighting composition.

25. The method of claim 20, wherein the composition is the composition of any of claims 11 to 15, and foaming is caused by contacting the foamable polymer (during its formation) with the blowing agent and copolymer compound; wherein, optionally, the copolymer compound is pre-mixed with the blowing agent as part of a blowing agent composition comprising the blowing agent and copolymer compound; wherein, optionally, the copolymer compound is pre-mixed with a polymerizable monomer(s) as part of a surfactantcontaining monomer composition comprising the copolymer compound and the polymerizable monomer(s).

26. A foamed composition obtained by the method of any of claims 20 to 25.

27. A foamed composition, comprising and/or formed by foaming the composition of any of claims 1 to 15.

28. A foamed composition, comprising a foam comprising the copolymer compound as defined in any of claims 1 to

15.

29. The foamed composition of any of claims 26 to 28, wherein the foamed composition is a hand-sanitizer foam.

30. The foamed composition of any of claims 26 to 28, wherein the foamed composition is a firefighting foam.

31 . The foamed composition of any of claims 26 to 28, wherein the foamed composition is a polymeric foam, suitably a polyurethane foam.

32. The composition of any of claims 1 to 15, the foam dispenser of any of claims 16 to 19, the method of any of claims 20 to 25, the foamed composition of any of claims 26 to 31 , or any preceding claim dependent thereon, wherein the copolymer compound has an HLB value between 6.5 and 13.5.

33. The composition of any of claims 1 to 15, the foam dispenser of any of claims 16 to 19, the method of any of claims 20 to 25, the foamed composition of any of claims 26 to 31 , or any preceding claim dependent thereon, wherein the weight ratio of M₁ to M₂ in the copolymer compound is between 3:1 and 1 :3, more suitably between 2:1 and 1 :2.

34. The composition of any of claims 1 to 15, the foam dispenser of any of claims 16 to 19, the method of any of claims 20 to 25, the foamed composition of any of claims 26 to 31 , or any preceding claim dependent thereon, wherein the mass fraction of M₁ in the copolymer compound is 0.25 to 0.75 whilst the mass fraction of M₂ in the copolymer compound is 0.75 to 0.25, wherein the sum of mass fractions for M₁ and M₂ total 1 .

35. The composition of any of claims 1 to 15, the foam dispenser of any of claims 16 to 19, the method of any of claims 20 to 25, the foamed composition of any of claims 26 to 31 , or any preceding claim dependent thereon, wherein the copolymer compound has a homogeneous polyacrylic backbone, a homogeneous polyalkylacrylic backbone, a homogeneous polyacrylamide backbone, or a homogeneous polymethacrylamide backbone.

36. The composition of any of claims 1 to 15, the foam dispenser of any of claims 16 to 19, the method of any of claims 20 to 25, the foamed composition of any of claims 26 to 31 , or any preceding claim dependent thereon, wherein: M₁ is a monomer having the formula M_1A:

wherein R_BT is either H or a (1 -2C)alkyl (e g. methyl), XT is O or NH, and RT is a pendent solvophobic group as defined in any preceding claim;

M₂ is a monomer having the formula M_a:

wherein R_B2 is either H or a (1 -2C)alkyl (e g. methyl), X₂ is O or NH, and R₂ is a pendent solvophilic group as defined in any preceding claim.

37. The composition, the foam dispenser, the method, or the foamed composition, of claim 36, wherein R_B1 is H or CH₃, XT is O, R_B2 is H or CH₃, and X₂ is O.

38. The composition of any of claims 1 to 15, the foam dispenser of any of claims 16 to 19, the method of any of claims 20 to 25, the foamed composition of any of claims 26 to 31 , or any preceding claim dependent thereon, wherein: wherever the copolymer compound comprises a (perfluorocarbon group, said (per)fluorocarbon group is part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide, suitably wherein the copolymer compound is otherwise free of fluorine atoms; and wherever the copolymer compound comprises a siloxane (suitably methyl siloxane moiety or perfluoromethyl siloxane moiety) group, said group is part of a hydrolysable moiety, such as an alcohol portion of an ester or amine portion of an acid amide, suitably wherein the copolymer compound is otherwise free of silicon atoms.

39. The composition of any of claims 1 to 15, the foam dispenser of any of claims 16 to 19, the method of any of claims 20 to 25, the foamed composition of any of claims 26 to 31 , or any preceding claim dependent thereon, wherein RT comprises a continuous carbon chain comprising at least 3 carbon atoms and at least one methyl group (or perfluoromethyl group).

40. The composition of any of claims 1 to 15, the foam dispenser of any of claims 16 to 19, the method of any of claims 20 to 25, the foamed composition of any of claims 26 to 31 , or any preceding claim dependent thereon, wherein R₂ is either H or a group that is free of any methyl groups (or perfluoromethyl groups), with the optional exception of a single terminal methyl group attached to a heteroatom, free of any continuous carbon chains comprising 3 or more carbon atoms, and comprises one or more heteroatoms (preferably one or more oxygen atoms)

41. The composition of any of claims 1 to 15, the foam dispenser of any of claims 16 to 19, the method of any of claims 20 to 25, the foamed composition of any of claims 26 to 31 , or any preceding claim dependent thereon, wherein R₂ comprises at least one heteroatom (e g. O or N, preferably O, such as OH, ester, or ether moieties), suitably at least two heteroatoms, more suitably at least three heteroatoms, most suitably at least four heteroatoms, suitably wherein R₂ has a chain length of at least 3, suitably at least 5, suitably at least 7.

42. The composition of any of claims 1 to 15, the foam dispenser of any of claims 16 to 19, the method of any of claims 20 to 25, the foamed composition of any of claims 26 to 31 , or any preceding claim dependent thereon, wherein the copolymer compound is selected from the group consisting of:

• A copolymer compound of Formula poly(PEGA-stat-EHA).

• A copolymer compound of Formula poly(PEGA-stat-EHMA).

• A copolymer compound of Formula poly(PEGA-stat-TMHA).

• A copolymer compound of Formula poly(PEGMA-stat-TMHA).

• A copolymer compound of Formula poly(PEGMA-stat-TMHMA).

• A copolymer compound of Formula poly(PEGA-stat-iOA). .

• A copolymer compound of Formula poly(GMA-stat-TMHA).

• A copolymer compound of Formula poly(AA-stat-TMHA).

• A copolymer compound of Formula poly(PEGMA-stat-TMSMA).

• A copolymer compound of Formula poly(MAA-stat-TMSMA).

• A copolymer compound of Formula poly(MAA-stat-HFBMA).

• A copolymer compound of Formula poly(PEGMA-stat-HFBMA).

• A copolymer compound of Formula poly(PEGA-stat-LA).

43. The composition of any of claims 1 to 15, the foam dispenser of any of claims 16 to 19, the method of any of claims 20 to 25, the foamed composition of any of claims 26 to 31 , or any preceding claim dependent thereon, wherein the copolymer compound is poly(PEGA-stat-TMHA).

44. The composition of any of claims 7 to 10, the foam dispenser of claim 18, or the method of any of claims 22 to 24, the foamed composition of claim 30, or any preceding claim dependent thereon, wherein the copolymer compound is poly(PEGMA-stat-TMSMA) or poly(GMA-stat-TMHMA).