WO2017050840A1

WO2017050840A1 - Synthetic foam material comprising silane-terminated polymers

Info

Publication number: WO2017050840A1
Application number: PCT/EP2016/072455
Authority: WO
Inventors: Sylvia R. Hofmann
Original assignee: Poly Terra Innovation Gmbh
Priority date: 2015-09-21
Filing date: 2016-09-21
Publication date: 2017-03-30

Abstract

The invention relates to a synthetic foam material comprising a crosslinked polymer network of one or more silane-terminated polymers (STP) suitable as a packaging material. The invention comprises preferably a foam and method for producing said foam using an external blowing agent or a combination of internal and external blowing agents. The invention further relates to a kit comprising at least two components separated in two or more vessels, that when brought into contact with one another lead to crosslinking of the STP material, and in combination with an external and optionally internal blowing agent, subsequent foam formation. The invention also relates to a method for the production of a synthetic foam material comprising a crosslinked polymer network of one or more silane-terminated polymers (STP) and the use of such a foam material in packaging and/or protection applications.

Description

SYNTHETIC FOAM MATERIAL COMPRISING SILANE-TERMINATED POLYMERS

DESCRIPTION

BACKGROUND OF THE INVENTION

Typical foam-in-place production in the packaging industry relies on sprayable polyurethane foams (PU foams). Before crosslinking, the foamable materials comprise prepolymers which have a high concentration of free isocyanate groups. These isocyanate groups are able to undergo addition reactions with suitable reactants resulting in curing of the spray foam after application. The foam structure may be generated by a volatile blowing agent being mixed into the still uncrosslinked raw material, or by means of carbon dioxide formed by reaction of isocyanates with water. Such foams may be supplied from pressure cans and ejected under the intrinsic pressure of the blowing agent, or be sprayed from nozzles or guns and allowed to foam upon reaction between an isocyanate and a polyol. Such foams are used for filling hollow spaces, especially in the building sector, and typically provide good thermal insulation.

PU spray foams are produced both as one-component (1 K) foams or two-component (2K) foams. The 1 K foams typically cure by contact of the isocyanate-containing prepolymer mixture with atmospheric moisture. The carbon dioxide liberated during the curing reaction of the 1 K foams can additionally aid foam formation. 2K foams typically consist of an isocyanate component and a polyol component which have to be intimately mixed with one another immediately before foaming and cure as a result of the reaction of the polyol with the isocyanates. An advantage of the 2K systems is an extremely short curing time of sometimes only a few minutes for complete curing to occur. The cured PU foams have excellent thermal insulation properties, show good adhesion to most substrates and have virtually unlimited stability under dry conditions. The PU foams are however typically very hard, isocyanate-based and poorly suited for use by untrained staff.

PU spray foams have the critical disadvantage that the isocyanate groups can, owing to their high reactivity, also display extreme irritant and toxic properties. Due to the health risks of such components, in particular isocyanate-based components, the existing PU foam solutions are presently deemed highly disadvantageous. There is a risk of toxicologically unacceptable compounds being inhaled by the end user when producing and/or when applying the foam. These risks are increased by the fact that PU spray foams are often used by untrained users and handymen, so that correct handling cannot be assumed.

The technical field of foam production, in particular in the packaging industry, requires alternative low-toxic, low-cost means for reliable foam production. Present hand-held direct-molding pouring or spraying foam systems, such as those produced by Sealed Air Instapak® in their custom foam packaging systems, are effective but are based on reactive isocyanates being applied in the spraying device.

The custom foam packaging technology is typically characterised by real-time molding of the foaming material in a packaging container, surrounding an item to be packaged, in pre-fabricated mold, or inside a bag or film. The mixture expands rapidly around the product being protected, creating a custom protective shell. This "foam-in-place" technology (otherwise referred to as "direct-foam" technology) represents an effective utilization of the properties of isocyanates and polyurethanes. The isocyanates enable both a gelling reaction (cross-linking) and a blowing reaction (expansion) when reacting with hydroxyl-containing components. The hard segments additionally support the mechanical stability by forming a physical network. However, the highly reactive isocyanates cause significant toxicological concerns due to their reactivity. A solution is therefore required in which dangerous isocyanates are no longer present during cross-linking or foam expansion.

It is possible to produce PU alternatives entirely free from isocyanates. This has been described in other applications, for example polyether backbone products are available as MS Polymer® products from Kaneka. However, these polymerization systems are not sufficiently reactive for the required short time periods relevant for direct-mold packaging applications.

Alternative isocyanate-free foam solutions have been described. For example, US 2012225225 A1 describes a low isocyanate foamable composition. The alkoxysilane-terminated prepolymers described therein are typically present in a can system (disposable pressure container) and employ internal blowing agents, such as hydrocarbons having 1 -5 carbon atoms or fluorinated hydrocarbons, thereby introducing additional safety and environmental concerns. The format for delivery (spray can), high costs, in addition to the hardness of the foams produced, make these foams poorly suited for foam-in-place packaging applications.

Other technologies, such as described in WO 2005049684 A1 provide silane terminated prepolymers (STP) with low isocyanate content for various applications. The compounds described therein have however not been used for foam applications in the packaging industry, as the required densities could not be obtained, and the blowing agents, viscosities, crosslinking times not appropriately established.

To the knowledge of the inventors, the prior art does not describe a non-isocyanate foam solution suitable for direct-foam packaging that shows the desired elastic and/or energy adsorbing properties for packaging, and that avoids an expensive spray-can format and/or environmentally unfriendly blowing agents. SUMMARY OF THE INVENTION

In light of the prior art the technical problem underlying the present invention is to provide a nontoxic (preferably isocyanate-free) synthetic foam, and means for producing such a foam, that enables a direct-foam packaging system.

This problem is solved by the features of the independent claims. Preferred embodiments of the present invention are provided by the dependent claims.

The invention provides foams and foamable materials based on isocyanate-free or low- isocyanate components (NCO content typically < 0.1 %). The foams described herein meet the requirements of packaging foam, defined primarily by low density, good energy (impact) absorption, and contoured in-situ foaming.

The preferred approach according to the present invention incorporates a refinement of isocyanates (NCO-prepolymers), in which the cross-linking reaction takes place via a further functional group, the amino-alkoxy-silanes, and expansion is achieved by supplying an internal and/or external blowing agent, preferably in combination, by way of physical foaming. Due to the quantitative conversion of NCO groups into urea-derived alkoxy-silyl-polyurethane prepolymers, non-toxic materials may be provided to the end user for foam production. Cross-linking within the foam product is carried out by means of silane condensation of silane terminated prepolymers (STP).

The invention therefore relates to a synthetic foam material comprising a crosslinked polymer network of one or more silane-terminated polymers (STP). In a preferred embodiment the invention relates to a synthetic foam material as described herein, wherein the foam material is produced by means of an external blowing agent.

To the knowledge of the inventors a crosslinked STP material has not been previously described having been produced using an external blowing agent. The external blowing agent leads to distinct physical and structural properties compared to the use of an internal blowing agent. An external blowing agent leads to greater control with respect to foam formation, due for example to the metering of propellant being added to the crosslinking (or partially crosslinked) material. Until the present time, the use of an external foaming agent to generate a foam material based on STP crosslinking was not considered practically feasible.

In a preferred embodiment the invention relates to a synthetic foam material as described herein, wherein the external blowing agent is CO2. The use of CO2 as an external blowing agent provides a number of advantages. CO2 can be entrapped within the cells of the foam structure, thereby acting as a carbon sequester, essentially functioning as an artificial reservoir that accumulates and stores CO2 for an indefinite period, thereby representing an environmentally friendly solution. CO2 is also particularly well suited as a blowing agent provided from an external source due to relatively low costs, good safety profile, fire protection and ease of use.

In a preferred embodiment the invention relates to a synthetic foam material as described herein, wherein the external blowing agent is a gas, preferably selected from the group consisting of CO2, nitrogen and/or air, such as compressed air. In a preferred embodiment the gas is entrapped in the foam structure. In a preferred embodiment the invention relates to a synthetic foam material as described herein, wherein the gas is CO2 and contributes to 2-35% by weight of the foam material, preferably 5- 30%, 8-25% by weight.

In one embodiment the foam material of the invention is produced using only an external blowing agent, without an internal blowing agent.

In a preferred embodiment the invention relates to a synthetic foam material as described herein, wherein the foam material is produced by means of a combination of external and internal blowing agents. Internal blowing agents are considered in the present invention preferably as an addition to the external blowing agent, or in some embodiments for use on their own without an external blowing agent.

Internal blowing agents relate preferably, without limitation, to CO2 (saturated components), (inorganic and/or organic) carbamates, such as the adduct of N-Methylethanolamine and CO2. Additionally or alternatively, low boilers such as propane/butane, DME and hydrofluorocarbons are contemplated. A blowing agent selected from fluorinated hydrocarbons, each with 1 -5 carbon atoms, may be incorporated.

The crosslinked system is preferably foamed using CO2. The dispersion of the CO2 and the expansion of the foam via an external foaming agent may however in some embodiments be supported by an intrinsic process. The intrinsic foaming with CO2 can happen in two or more ways, by the release of dissolved CO2 from the components and/or by chemical means. External blowing, and internal blowing via release of dissolved CO2 and additional chemical blowing agents may be combined. Through a combination of blowing agents a surprisingly effective foaming is obtained, sufficient to enable capture of the external blowing agent.

Gas formation, such as in the form of an internal blowing agent, during the process of crosslinking the STP compounds may, in a preferred embodiment, be obtained via the reaction between two separate reactants, which together can cause gas formation on contact.

Any of the proposed compounds may be incorporated into the method or kit of the present invention accordingly.

In a preferred embodiment the invention relates to a synthetic foam material as described herein, wherein the foam material exhibits a density of 50 kg/m³ or less, 30 kg/m³ or less, 20 kg/m³ or less, preferably 12 kg/m³ or less, more preferably 10 kg/m³ or less, or more preferably of 8 kg/m³ or less. These densities represent preferred densities for the foam of the invention to be used as packaging, in particular in the context of direct pour packaging foam suitable for setting into its final form after foam production. Foam densities of these values have not previously been achieved using crosslinked STP materials.

In a preferred embodiment the invention relates to a synthetic foam material as described herein, wherein said foam material exhibits a cross-linked polymer network with elastic properties and/or energy absorbing properties. These properties are suitable for the foam of the invention to be used as packaging, in particular in the context of direct pour packaging foam suitable for setting into its final form after foam production. In one embodiment the invention relates to a synthetic foam material as described herein, wherein the STP component is obtained from (i) one or more aminoalkoxysilane-reactive polymeric resins and (ii) one or more aminoalkoxysilane components.

In another embodiment the invention relates to a synthetic foam material as described herein, wherein the STP component is obtained from (i) one or more NCO-Prepolymers and (ii) one or more aminoalkoxysilane components.

In a preferred embodiment the aminoalkoxysilane component is an alpha-aminomethyl di- or tri- alkoxysilane and/or a gamma-aminopropyl di- or tri-alkoxysilane.

In one embodiment the invention comprising the use of NCO-Prepolymers, the NCO-Prepolymer prior to reaction with an aminoalkoxysilane component exhibits an NCO-content of 15% or less, preferably less than 10%, most preferably of 4%-8%, in particular 6%, and wherein the STP component obtained by reaction of an NCO-Prepolymer with an aminoalkoxysilane component exhibits an NCO-content of less than 1 %, preferably less than 0.1 %. Through the use of these components a low-isocyanate system, an isocyanate-free system or an essentially isocyanate- free system is provided for use in a packaging context.

In one embodiment the invention relates to a synthetic foam material as described herein, wherein the NCO-Prepolymer prior to reaction with an aminoalkoxysilane component exhibits a molecular weight of 500-5000 g/mol, preferably 750-4000 g/mol, more preferably 1000 to 3000 g/mol. These molecular weights enable the preferred foam properties of appropriate elastic properties and/or energy absorbing properties, in addition to the required stability and strength of the foam in order to entrap an external blowing agent, preferably CO2, and provide a stable and strong foam material suitable for use in the direct-pour foam packaging technology.

In one embodiment the invention relates to a synthetic foam material as described herein, wherein the STP component is obtained from (i) one or more NCO-functionalized

alkyl alkoxysilane components and (ii) one or more polymeric components with at least one OH group.

In one embodiment the invention relates to a synthetic foam material as described herein, wherein the STP component prior to cross-linking exhibits a molecular weight of 750-8000 g/mol, preferably 1000-7000 g/mol, more preferably 2000 to 6000 g/mol. These molecular weights enable the preferred foam properties of appropriate elastic properties and/or energy absorbing properties, in addition to the required stability and strength of the foam in order to entrap an external blowing agent, preferably CO2, and provide a stable and strong foam material suitable for use in the direct-pour foam packaging technology.

In one embodiment the invention relates to a synthetic foam material as described herein, wherein the STP component prior to cross-linking comprises 2-12, preferably 3-9, or 6-9, reactive alkoxysilane groups per molecule. These values of cross-linking sites within the STPs enable the preferred foam properties of appropriate elastic properties and/or energy absorbing properties, in addition to the required stability and strength of the foam. In one embodiment the invention relates to a synthetic foam material as described herein, wherein the STP component prior to cross-linking comprises 2-20, preferably 4-10, reactive crosslinking sites per molecule. A "reactive crosslinking site" is to be understood as any silanol group or Si-OR group with preceded hydrolysis. Crosslinking is typically considered the process of chemically joining two or more molecules by a covalent bond and crosslinking agents contain reactive end-groups for specific functional groups. According to the present invention the preferred reactive cross-linking comprises an Si-alkoxy > Silanol > Siloxane crosslinking process, beginning at a reactive site, such as an alkoxy-silane group, by reacting with water and/or a base catalyst.

In one embodiment the invention relates to a synthetic foam material as described herein, wherein the STP component comprises one or more structures according to Formula I :

wherein

X = O or NH ;

" = a substituent of the following structure:

wherein R = Alkyl, preferably methyl or ethyl, or Alkoxy, preferably OMe or OEt, wherein at least 2 R groups, preferably 3 R groups, attached to Si are Alkoxy;

R' = H, Alkyl, preferably cyclohexyl, Aryl, preferably phenyl, or R";

n = 0-6, preferably 1 -3.

In one embodiment the invention relates to a synthetic foam material as described herein, wherein the polymer network of one or more crosslinked silane-terminated polymer (STP) components comprises one or more additional cross-linked polyol components.

In one embodiment the invention relates to a synthetic foam material as described herein, wherein the polyol component

(i) exhibits an OH-Number of 2 or more, preferably 2-5; and/or

(ii) is a polyetherol, polyesterol, OH-prepolymer, saccharide, polysaccharide, starch and/or oil, such as castor oil or an OH-group comprising derivative thereof, soya bean oil or an OH-group comprising derivative thereof, or linoleic based oil or an OH-group comprising derivative thereof.

In one embodiment the invention relates to a synthetic foam material as described herein, comprising additionally propylene carbonate.

In one embodiment the invention relates to a synthetic foam material as described herein, comprising a flame retardant, such as Triethyl Phosphate (TEP) and or Tris-(1 -chloro-2- propyl)phosphate (TCPP).

In one embodiment the invention relates to a synthetic foam material as described herein, comprising a viscosity modifier. The viscosity modifier is intended to modify the viscosity of the component before or during cross-linking, in order to provide an optimal viscosity for component storage, provision of the component to the foaming/pouring device and/or for capture of an external blowing agent during cross-linking.

The use of viscosity modifiers described herein relates to a non-obvious selection leading to unexpected properties of the foam material described herein. Previous attempts described in the art with respect to foam production from STP materials have been plagued by serious difficulties with respect to optimal viscosities, in particular towards finding a balance between low viscosity during storage and provision of the components to foaming device, and a sufficiently high viscosity during cross-linking to capture an external blowing agent and provide sufficient structural stability during blowing to enable stable foam formation. The components described in detail below enable effective properties with respect to the desired viscosities.

In one embodiment the invention relates to a synthetic foam material as described herein, wherein the viscosity modifier is one or more selected from the group consisting of glycerol, polypropylene glycol and polyethylene glycol.

In one embodiment the invention relates to a synthetic foam material as described herein, comprising a water scavenger, such as Vinyltri(m)ethoxysilane.

In one embodiment the invention relates to a synthetic foam material as described herein, comprising a cross-linking agent, such as Tetraethyl orthosilicate.

In one embodiment the invention relates to a synthetic foam material as described herein, comprising a plasticizer. A preferred plasticizer is Mesamoll™ Lanxess. PC, PEG and emulsifiers or stabilizers may also show a plasticizer effect.

In one embodiment the invention relates to a synthetic foam material as described herein, comprising a silicone surfactant, preferably a short chain siloxane backbone with one or more PEG-substituents (PEG-chains), an organic surfactant, such as an ethoxylated oxo-alcohol, such as are available from SASOL, and/or an associative thickener, such as are available from BYK. The surfactants described herein enable stable blending of the two components required for crosslinking of the STP materials.

In a preferred embodiment the invention relates to a synthetic foam material as described herein, wherein the material comprises an agent for enhanced CO2 adsorption or capture, such as 2- methylaminoethanol. Through the use of this agent the CO2 adsorption is enhanced, thereby enabling improved foam formation due to CO2 capture when CO2 is used as an external and/or internal blowing agent.

In a preferred embodiment the synthetic foam material comprises (% by weight):

a. a polymer network of one or more crosslinked silane-terminated polymer (STP) components according to any one of claims 4 to 14,

at 40-70%, preferably 45-65%;

b. flame retardant, preferably TEP,

at 0.1 -5%, preferably 0.5-4%; and c. one or more viscosity modifiers, silicone and/or organic surfactants, agents for enhanced CO2 adsorption or capture, and/or compiling products at 15-45%, preferably 20-35%,

preferably selected from:

the viscosity modifiers consisting of glycerol, polypropylene glycol, polyethylene glycol,

a silicone surfactant, preferably a short chain siloxane backbone with one or more PEG-substituents (PEG-chains),

an organic surfactant, preferably an organic surfactant, such as an ethoxylated oxo-alcohol, such as are available from SASOL, and

an associative thickener, such as are available from BYK,

2-methylaminoethanol.

In one embodiment the foam material comprises d) one or more catalysts (0.1 -7%) comprising preferably a base, such as KOH.

The provision of a synthetic foam material on the basis of these materials, in these relative proportions, enables an effective foam for packaging applications. The relative proportions of the individual materials of the foam material may also be derived from the components provided in the preferred embodiments regarding the kit or method of the invention described herein.

A further aspect of the invention relates to a kit for the production of a synthetic foam material, for example as described herein, comprising at least two components separated in two or more vessels, wherein each component is preferably present as a product blend, wherein

(i) a first vessel (component 1 ) comprises a liquid or solution comprising at least one silane- terminated polymer (STP) component according to any one of the preceding claims, and

(ii) a second vessel (component 2) comprises at least H₂0 and a catalyst, such as KOH.

The term "component" as used herein relates to a liquid comprising one or more materials to be added with other "components" during production of the STP material, preferably a blend or solution, comprising in some cases multiple materials.

The kit described herein represents one of the practical implementations of the present invention. The foam material described herein is typically produced via the mixture of two or more

"components", each component comprising materials that, when brought into contact with one another, lead to crosslinking of the STP material, and in combination with an external and optionally one or more internal blowing agents, subsequent foam formation. The invention therefore relates to a kit comprising two or more vessels, each containing a "component", wherein the combined components are suitable for producing the foam of the present invention.

In a preferred embodiment the invention relates to a kit for the production of a synthetic foam material as described herein, wherein a first vessel (component 1 ) comprises

(i) a solvent, preferably propylene carbonate; and/or

(ii) a flame retardant, such as Triethyl Phosphate (TEP) and/or Tris(1 -chloro-2-propyl)phosphate (TCPP). In a preferred embodiment the invention relates to a kit for the production of a synthetic foam material as described herein, wherein the second vessel (component 2) comprises

(i) a viscosity modifier, preferably selected from the group consisting of glycerol, polypropylene glycol and polyethylene glycol, and/or

(ii) an agent for enhanced CO2 adsorption or capture, preferably 2-methylaminoethanol.

In a preferred embodiment the invention relates to a kit for the production of a synthetic foam material as described herein, wherein at least one vessel (component 1 and/or 2) comprises one or more of

(ii) a surfactant, such as a silicone surfactant as described herein, and/or an organic surfactant such as described herein.

In a preferred embodiment the kit for the production of a synthetic foam material as described herein comprises at least two components, each component preferably present as a product blend, in two or more separate vessels,

wherein a first vessel comprises a liquid or solution comprising (% by weight):

a. 50-90%, preferably 60-80%, silane-terminated polymer (STP);

b. 0.5-30%, preferably 1 -15%, fire retardant, preferably TEP;

c. 1 -10%, preferably 2-6%, organic surfactant,

d. 5-20%, preferably 10-15%, solvent and/or a viscosity reducing agent, preferably propylene carbonate;

wherein a. to d. add to 100%, and

a second vessel comprises a liquid or solution comprising:

e. 2-20%, preferably 4-16%, catalyst, preferably a base, such as KOH solution in water, such as a 1 -10% KOH solution, preferably 2-7%;

f. 20-60%, preferably 25-50%, viscosity modifier, preferably selected from the group consisting of glycerol, polypropylene glycol and polyethylene glycol; g. 20-60%, preferably 25-50%, one or more surfactants, such as a silicone surfactant and/or an organic surfactant and additionally an associative thickener, and/or

h. 0-20%, preferably 5-15%, of an agent for enhanced CO2 adsorption or capture, preferably 2-methylaminoethanol;

wherein e. to h. add to 100%.

In a preferred embodiment the invention relates to a kit for the production of a synthetic foam material as described herein, wherein at least one of the at least two components, each component preferably present as a product blend, is loaded with CO2. In a preferred embodiment the invention relates to a kit for the production of a synthetic foam material as described herein, wherein the at least two components comprise less than 0.1 % NCO-content. The low isocyanate content of the present invention represents a significant improvement over similar packaging solutions. Until present, to the knowledge of the inventors, no system has been described in the art that is essentially isocyanate-free (or exhibits low to negligible levels of isocyanate) that is capable of producing a foam material suitable for direct pouring foam packaging solutions.

In a preferred embodiment the invention relates to a kit for the production of a synthetic foam material as described herein, wherein the kit is present in the form of a foam pouring unit.

A further aspect of the invention relates to a method for the production of a synthetic foam material as described herein, comprising:

a. bringing a liquid comprising a silane-terminated polymer (STP) component as described herein (component 1 ) into contact with a liquid comprising at least H₂0 and a catalyst, such as KOH (component 2);

b. Mixing the components 1 and 2 under conditions suitable for chain growth and/or for polymer network formation via cross-linking;

c. Contacting said mixture with an external and/or internal blowing agent at an intermediate stage of polymer network formation; and

d. Discharge or pouring of said mixture as a foam according to the synthetic foam material according to any one of the preceding claims.

In a preferred embodiment the features of the kit are incorporated herein with reference to components 1 and 2 of the method, for example in step a.

In a preferred embodiment of the invention the method is characterised in that the external blowing agent is CO2 gas.

In a preferred embodiment of the invention the method is characterised in that the external blowing agent is liquid CO2.

In a preferred embodiment the invention relates to a method for the production of a synthetic foam material as described herein, wherein the synthetic foam material is produced by means of a combination of external and internal blowing agents.

In one embodiment the invention relates to a method for the production of a synthetic foam material as described herein, wherein the internal blowing agent is outgassing of gas, such as CO2, from a solution, or enables production of a gas, such as CO2, from a reactive component through the input of chemical, kinetic or thermal energy.

In one embodiment the invention relates to a method for the production of a synthetic foam material as described herein, wherein the synthetic foam material is at least partially polymerized and exhibits elastic properties within 3 minutes after foam discharge, preferably within 1 minute after foam discharge. In one embodiment the invention relates to a method for the production of a synthetic foam material as described herein, wherein the synthetic foam material exhibits an least partially crosslinked network and exhibits the strength and mechanical stability to resist a mechanical strain or load typically encountered during transport or storage of a cardboard container within 60 minutes after foam discharge, preferably within 30 minutes after foam discharge, more preferably 10 minutes after foam discharge.

In one embodiment the invention relates to a method for the production of a synthetic foam material as described herein, wherein:

(i) component 1 is according to the first component as described in the context of the kit of the present invention,

(ii) component 2 is according to the second component as described in the context of the kit of the present invention, and

(iii) the components 1 and 2 are added at a ratio of 10:1 to 1 :2, preferably 3:1 to 1 :1 , more preferably 2:1 .

In one embodiment the invention relates to a method for the production of a synthetic foam material as described herein the method is carried out between 15 and 80 deg C, preferably between 20 and 60 deg C.

In one embodiment the invention relates to a method for the production of a synthetic foam material as described herein, wherein the discharge of the foam occurs using a hand-held pneumatically driven discharge gun, pouring gun, pourer or pouring nozzle.

In one embodiment the invention relates to a method for the production of a synthetic foam material as described herein, wherein the ratio of the mixture of components 1 and 2 to gas is 50:1 to 3:1 by weight.

In a preferred embodiment the invention relates to the use of components in the method or kit described herein with "low viscosity", such as q2o °c = 100-10.000 mPa-s, preferably 200-2000 mPa-s. In a preferred embodiment the ratio of the viscosities of the components 1 and 2 is ryl /n2 = 10:1 to 1 :1 , preferably 6:1 to 2:1 , preferably 4:1 .

The invention further relates to a synthetic foam material obtainable by the method as described herein.

A further aspect of the invention relates to the use of a synthetic foam material as described herein, and/or the method for producing a synthetic foam material as described herein, as a protective packaging for an item to be encompassed (wrapped and/or packaged) by said foam.

The invention therefore relates to the use of a synthetic foam material as described herein, wherein the foaming mixture is poured into a closable bag or foil, in order to avoid direct contact between the foam and item of interest (to be packaged).

The invention further relates to a use of a synthetic foam material as described herein, or the method for producing a synthetic foam material as described herein, for protective packaging, wherein said use comprises direct injection of the foam material, such that the foam takes on the shape of an item to be encompassed by said foam. The potential uses of the foam relate to void-fill, product cushioning, block-and-brace for stabilizing heavy objects, pre-molding for standard post-sized packages, foam-in-bag

applications, direct-injection, pouring or spraying.

The description of particular features in the context of the foam material, kit, method or use is not intended to be limited to each particular aspect of the invention. The features disclosed herein, for example in the context of the foam, may also be considered as applicable to other aspects of the invention, for example to the kit or method.

FIGURES

The invention is further described by the figures. These are not intended to limit the scope of the invention.

Short description of the Figures:

Fig. 1 : Reaction tracking: Progression of a urea band (absorbance at 1682 cm ¹) and temperature against the reaction time during the synthesis of STP-1 .

Fig. 2: Comparison of the IR spectra of the isocyanate Desmodur E22 and STP-1 .

EXAMPLES

The invention is further described by the following examples. These are not intended to limit the scope of the invention. The experimental examples relate to the development and testing of various foam materials according to the present invention.

Silane terminated prepolymers have been produced and prepared as foamable components for subsequent cross-linking. The cross-linking reaction and the increase in viscosity were analyzed over time, and suitable reaction parameters were identified for rapid homogeneous cross-linking suitable for foam formation using an external propellant or blowing agent, preferably in combination with an internal agent. The systems tested with respect to process and product parameters yield a "ready-to-use" two-component (2K) system. A PU spraying machine has been adapted to a 2K system using a component ratio of 2:1 and a supply of the external blowing agent, which is preferably CO2, along with the a gas dispenser unit and mixing equipment.

In addition to the synthesis of suitable STPs for the desired resulting foam properties, formulations have been developed in which the components are provided and formulated with additives so that the desired process and product parameters are obtained. These additives include in particular surfactants to increase the compatibility of the two components with each other and with the gas phase. In addition, viscosity regulators and components for increasing CO2 absorption (binding capacity, fixation), catalysis and/or flame retardation are used.

Brief description of the synthesis and technical requirements:

The production of the foams as shown herein incorporates, by way of example, the following starting materials and intermediates:

- NCO prepolymers (optionally polyols and isocyanates as starting materials)

- Silane terminated prepolymers (STP) - Water, catalysts

- Additives (surfactants, viscosity modulators, CO2 adsorbers and/or flame retardants)

The NCO prepolymers are commercially available in a wide product range. The selection of NCO prepolymers that have a low NCO content (< 10%) and low viscosity (for example «10,000 mPa-s @25°C) are preferred. STPs are produced preferably by reacting the NCO prepolymers with aminoalkoxysilanes (o- and/or y-silanes).

The formulations and process control are intended to allow the production of foams that have settable properties. The selection of suitable components, the mixing ratios, and the blowing agent (preferably CO2) metering make a wide spectrum of properties possible. For this purpose, a parameter range using different STPs has been defined. The foam formulations are composed of the STPs or an STP blend, which may differ in terms of the following parameters:

- Functionality (branching/number of functional groups)

- Equivalent molar masses (segment chain lengths)

- Type (end groups) with respect to "reactivity" (o- or y- silane derivative)

A tool box of STPs has been created. The selection of the materials and their contents in the formulations are unique and tailored to the packaging application (although may be suitable for further uses) and enable a broad property profile for the resulting foams, from rigid to flexible foams, across a defined but broad density range. Priority has been given during testing to the following processing parameters of the components and reaction mixtures and the resulting foam properties:

Process parameters:

- Viscosity (profile of the increase in viscosity)

- Curing times (a large part of the reaction is completed within approx. less than 2 minutes, preferably less than 30 s)

Product parameters:

- Density (low density foams, 8-20 kg/m³)

- Mechanical properties (hardness and elasticity, dimensional stability and energy absorption)

- Insulating properties (for further uses)

Chemical development:

The following aspects of the invention have been practically implemented:

A) Examination of the cross-linking reaction and setting of the reaction times

- Crosslinking experiments with the individual components and formulations

o catalyst amount and temperature

o blend composition

o component composition (additives)

- Foaming using external blowing agents (CO2 and Nitrogen, dry or compressed air)

B) Creation of a tool box for optimizing the process and foam parameters

- Reactivity (adapting the reaction rates to the residence times)

- Setting the curing times - setting the compatibility/miscibility

- Setting the viscosities

- Controlling the mechanical hardness and flexibility (density minimization vs. foam

stability)

- Minimization of price

Examination of further STPs based on further NCO-prepolymers and aminosilanes

- Expansion of the synthesis matrix

- STPs based on branched prepolymers

- STPs with different functionalities

- STPs with different viscosities

- STPs based on stripped prepolymers

Development of a second reactive component

- Introduction of a supporting cross-linking reaction

- Transesterification with OH-terminated polymers (catalysis)

- Development of further cross-linking concepts (addition, condensation, cross-linking) Development of formulations using new raw materials

- Use of renewable resources

- Prepolymers based on MDI polymeric units

- selective conversion of Prepolymers with (branched) chain extenders

Machine development:

- Development of a suitable discharge/pouring device for production of the foam material o Adaptation of the pumping and delivery mechanism to accommodate two components (viscosities and volume ratios) and CO2 metering.

Synthesis of the silane terminated prepolymers (STPs):

The STPs were prepared by reacting NCO prepolymers with aminosilanes. Combinations of different prepolymers with the o- and y-silanes are used. To improve clarity, the following simplifications and abbreviations are introduced. Aminoalkyltrialkoxysilanes are used, and depending on the chain length of the alkyi chains or the position of the amino group at the alkyi chains, they are referred to as o- and y-silanes. The designation σ-amines that is used refers to σ-aminomethyltrialkoxysilanes, and the designation y-silanes refers to y- aminopropyltrialkoxysilanes.

NCO prepolymers are generally complex mixtures that are composed of different constituents. For example, by virtue of the manufacturing process many NCO prepolymers contain an excess of free isocyanates and possibly viscosity regulators, reaction stoppers, stabilizers, etc.

simplified structure of a prepolymer

Scheme 1. Composition of a commercially available PPG-based NCO prepolymer and the simplified representation used hereafter for clarity reasons.

The reaction schemes provided herein are by way of example and show a schematic

representation of the chemical reaction occurring. The units described with n may relate to any given number, for example from 1 to x, wherein x is any value. A skilled person is aware of the components used as NCO-prepolymers and may select, on the basis of the information provided herein, a suitable NCO-prepolymer structure.

The exact composition of the NCO prepolymers may vary depending on manufacturer. The prepolymers are based on a polyol skeleton, which is generally composed of polyetherols (PPG or PEG, optionally copolymers) or polyesterols. These polyols are used in different molar masses (500-5000 g/mol, depending on the application; for flexible foams, for example approx. 2000- 3000 g/mol) and degree of branching/functionalities (2-5). In addition, the isocyanate type may vary. MDI as the isocyanate source opens up additional variation options. The functionality of the prepolymer can be set by the use of the MDI type, monomeric or polymeric MDI. The reactivity and viscosity can be set via the isomer ratio of 2,4'-MDI and 4,4'-MDI as well as the

concentration. For better illustration, the simplifying chemical formula for the prepolymers is used in the following reaction equation.

STP s nthesis (secondary aminosilanes):

Scheme 2. Example reaction equation for the synthesis of an STP.

X g (1 mole) prepolymer is heated to 50^QC and, while stirring (overhead stirrer), X g (F- 1 mole (F = functionality of the prepolymer)) aminosilane is added dropwise; if necessary, an excess of silane should be used later so as to bring the NCO content below 0.1 %. The reaction is monitored and tracked. For reaction tracking purposes, the torque of the overhead stirrer, IR spectra, and the temperature of the reaction medium are measured. The reaction mixture is then stirred for approx. 1 h at 80°C until no isocyanate groups can be detected by way of IR. NCO content (wet chemically, IR and chromatographically after derivatization) and viscosity

(temperature profile and long-term study) are also assessed.

STP nthesis (primary aminosilanes):

Scheme 3. Example reaction equation for the synthesis of an STP.

X g (0.5 mole) prepolymer is heated to 30^QC and, while stirring (overhead stirrer), X g (F-0.5 mole (F = functionality of the prepolymer)) aminosilane is carefully added dropwise. The temperature is monitored. If necessary, an excess of silane should be used later so as to bring the NCO content below 0.1 %. The reaction mixture is then carefully stirred until no isocyanate groups can be detected any longer (e.g., using online IR as the detection method). Before the syntheses are carried out, the compatibility of the prepolymer and aminosilane is tested in preliminary tests.

Cross-linkin :

STP 1

water, strong base, such as KOH or amines

RT und 50 °C

- EtOH

Scheme 4. Representation of the cross-linking reactions.

5 to 20 g STP or of an STP blend is mixed with 0.5 to 1 mole water per mole ethoxy units (optionally catalyst) while stirring vigorously (for several seconds). The reactions are carried out at RT and at 50^QC (components heated to 50^QC). The reaction is tracked. Reaction tracking:

- Increase in viscosity: The viscosity is phenomenologically examined within the first minute (5 min in the case of slow reactions). If necessary, measurements are later carried out during the cross-linking reaction on the vulcameter.

- The following points in time are measured:

o Cream time eam ; point in time at which a cloudy creamy compound is formed o Tack time t_tack_y; point in time at which the compound begins to stick

o String time t_sinn_g ; point in time at which strings can be pulled from the tacky compound. o tack-free time ttack-fre_e: the time without tack, the time at which the surface of the

reaction mixture no longer feels tacky,

o Gumming time t_gUm ; point in time at which an elastic rubber-like state is reached, o Condition after 5 min; a certain hardness level should now have been reached since starting at approx. this point in time it should be possible to apply a load on the foam.

Cross-linking with formulations:

4 to 10 g of component 1 , which primarily consists of an STP or an STP blend, is mixed with 2 to

5 g of component 2, which contains an aqueous catalyst (e. g. KOH) solution and different additives in variable concentrations, while stirring vigorously (for several seconds). The reactions are carried out at RT and at 50^QC (components heated to 50^QC). The compatibility of the individual components among each other and the viscosity of the components prior to the reaction are determined. After the components have been mixed, the reaction is tracked analogously to the standard cross-linking procedure. The reaction is tracked phenomenologically by the increase in viscosity and represents the progression of the curing process.

Synthesis matrix:

A tool box of different STPs was produced. The STPs were synthesized from prepolymers and aminosilanes with different properties. The reaction parameters and resulting foam properties can be controlled via the selection of the individual materials. The table provides an overview of the produced STPs.

Table 1. Synthesis of the STPs from the prepolymers and aminosilanes.

j and STP-

Components:

NCO prepolymers:

Different NCO prepolymers are examined as the basis for the STP synthesis. The prepolymers differ with respect to the NCO content, functionality, and the "polyol skeleton." This results in different viscosities and cross-linking properties. The prepolymers may also considerably differ in the residual monomer content or the content of free MDI, and in the type of the isocyanate component (monomeric vs. polymeric and isomer ratio). This results in different properties in the process control and the resulting foam.

Prepolymer 1 = Desmodur E22 (Bayer Material Science)

- NCO content = 8.6 ± 0.3%; measured at IAP as 8.79% in a wet-chemical process

- Assumption: linear, PPG-based

- Functionality F = 2.0-2.8

- Free MDI = 10-12%

- Isomers = 2,4'-MDI and 4,4'-MDI

Prepolymer 1 B PC MD 8.6

- NCO content = 8.6%

- Free MDI = approx. 10%

- Polyol skeleton = PPG 2000 + polymeric MDI

- Additives = flame retardants; added to the melt to prevent the formation of high viscosity-yielding agglomerates

Prepolymer 2 trifunctional prepolymer (F=3 or closer to 2.8)

Polyol structure = triol, Mn = 4800 g/mol

NCO content = 9.3%

Viscosity = 3300 mPa-s

Free MDI = 1 -10%

Prepolymer 3 linear prepolymer, PPG 1000-based

Prepolymer 4 Desmodur E XP 2726 (Bayer MS)

NCO content = 6.0%

Functionality 2.0-2.8 (linear plus polymeric MDI)

Viscosity q= 4.500 mPa-s (@23°C) Prepolymer 5 = SUPRASEC 1007 (Huntsman)

- NCO content = 6.8%

- Functionality = 2.1

- q = 5.500 mPa-s (@25°C)

Prepolymer 6 = SUPRASEC 2234 (Huntsman)

NCO content = 16.0%

F = 2.5

- q = 2.500 mPa-s

Prepolymer 7 = SUPRASEC 2030 (Huntsman)

NCO content = 28.6%

- q = 175 (@25°C)

Prepolymer 8 = based on a polycarbonate polyol

NCO content = 5.2%

Fpolyolm= 3-4

Prepolymer 9 = MDI buttoms-based

Silanes:

The NCO prepolymers are reacted with aminosilanes to form the STPs. The silanes used are listed below:

σ-silane: (N-phenylamino)methyltriethoxysilane, CAS: 3473-76-5

- PC 171 1

- very reactive during cross-linking

ring reaction with isocyanates

SiBib (PC 1711 )

C₁₃H₂3N0₃Si

M=269.41 g/mol y-silane 1 : Bis[(3-triethoxysilyl)propyl]amine; CAS: 13497-18-2; EINECS: 236-818-1

- Dynasylan 1 122 (Evonik) , PC 1 108

- strongly cross-linking, but rather slowly

- easily controllable reaction with isocyanates

(EtO)₃Si ^^^^N^^^Si(OEt)₃

H

γ-Aminosilan 1

SiSiB PC 1108 (CAS 13497-18-2)

C₁₈H₄₃N0₆Si2,425,71 g/mol y-silane 1 B: Bis[(3-trimethoxysilyl)propyl]amine; CAS: 82985-35-1 ; EINECS: 240-084-5

- (PC1 108, PCC)

- strongly cross-linking, but rather slowly

- easily controllable reaction with isocyanates

(MeO)₃Si N^^^^Si(OMe)3

H

γ-Aminosilan 1B

SiSiB PC 1108 (CAS 13497-18-2)

C₁₂H₃ N0₆Si2, M= 341 g/mol y-silane 2: 3-aminopropyltrimethoxisilane (AMMO); CAS: 13822-56-5; EINECS: 237-51 1 -5

- PC 1 1 10 (PCC)

- reaction carrier (condensation)

- reacts strongly with isocyanates

- liberates methanol

(MeO)₃Si^^^^NH₂

AMMO (PC 1110)

C₆H₁₇N0₃Si

M=179.29 g/mol y-silane 2B: aminopropyltriethoxysilane, CAS: 919-30-2; EINECS: 213-048-4

- Dynasylan AMEO (Evonik)

- reaction carrier (condensation, hydrolysis)

- reacts strongly with isocyanates

(EtO^Si^^^^NHz

PC 1100 CAS: 919-30-2

CgH₂3N0₃Si

M=221.30 g/mol y-silane 3: N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, CAS: 1760-24-3, EINECS: 217-164- 6

- strongly cross-linking, already during STP synthesis

γ-Aminosilan 3 (DAMO)

C8H22N2O3S, M= 222.36 g/mol y-silane 4: tetraethoxysilane, CAS: 78-10-4, EINECS: 201 -083-8

- TEOS; Dynasylan A (Evonik)

- diluent

- cross-linking agent

TEOS, C₈H₂₀O₄Si

Molecular Weight: 208.33 g/mol y-silane 5: Mixture of silanes 1 and 2b (plus high boiler)

Additives:

The additives are used to improve the processing properties and the resulting foam properties. Functional additives such as viscosity regulators and foam stabilizers are used, as well as filler materials to appropriately adapt the volumes of the two component flows.

Polyols:

- PEG 2000; Arcol®Polyol PPG 2000 (Bayer Material Science)

- PEG 1000; Arcol®Polyol PPG 1 000 (Bayer Material Science)

- PEG 400; ArcolOPolyol 1 004

- Glycerin, CAS: 56-81 -5, EINECS: 200-289-5

Surfactants/emulsifiers:

The surfactants are used to increase the stability of the two components and their miscibility. Increased miscibility is presumed to expedite the reaction; at least a positive effect on the curing rate was observed. In addition, the silicone surfactants serve as foam stabilizers. They also bind impurities that would adversely affect the foam process and stabilize the gas bubbles and froth until the cured polymer matrix holds the foam. The membranes/cell walls should also be opened to obtain a partially open-cell foam ; this is useful for lower densities and reduces shrinkage.

Organic surfactants:

- Triton® X-1 00, f-Octyl phenol ethoxylate; CAS: 9002-93-1

- LIALET 1 1 1 -10, Ethoxyliertes Undecanol; CAS: 34398-01 -1 : EINECS: not defined, polymer

- LIALET 1 1 1 -5.5, Ethoxyliertes Undecanol; CAS: 34398-01 -1 : EINECS: not defined, polymer Silicone surfactants:

- Dabco® DC193 Surfactant (AIR PRODUCTS) ;

- Niax^* silicone L-580 (Momentive) ; CAS:

Associative thickeners:

- Optiflo-H 7500 VF

- Optiflo-H 600 VF

- Optigel WM

CO? binder:

- Propylencarbonat, CAS: 108-32-7,

- Dimethylencarbonat, CAS: 61 6-38-6, EINECS: 210-478-4 - N-Methylaminoethanol (MAE), CAS: 109-83-1 , EINECS: 203-710-0

- Polypropylene carbonate

Plasticizers:

Benzoflex 9-88 is used industrially for elastomer applications and serves as a softener or plasticizer. Plasticizers may assist expansion in an advanced state of crosslinking.

Benzoflex 9-88, Dipropylene glycol dibenzoate, CAS: 27138-31 -4. EINECS: 248-258-5

Flame retardants:

- Tris(1 -chloro-2-propyl)phosphate (TCPP), CAS: 13674-84-5

- Triethylphosphat (TEP), CAS: 78-40-0, EINECS: 201 -1 14-5

Synthesis of STP-1 (prepolymer 1 + a-silane PC 1711):

The synthesis was carried out in a 250 ml_ double-walled reactor with a propeller mixer. The reactor was equipped with a ReactIR® probe, a dropping funnel, a Dimroth condenser, and a dr ing tube containing calcium chloride.

STP 1

Scheme 5. Reaction equation of the synthesis of STP-1 .

100 g (0.2047 mole NCO groups) Desmodur E 22 (from Bayer Material Science) was heated to 50°C and, while stirring (250 rpm, with torque transducer), 55.1 g (0.2048 mole) SiSiB® PC 171 1 (from Power Chemical Corporation Limited) was added dropwise (52 min). The reaction mixture was then stirred for 1 h at 80°C until no isocyanate groups were detectable any longer or no further formation of urea bonds was observed. The mixture was then cooled to RT and filled into a PE bottle.

Using the ReactIR®, the temperature curve and the development of the absorption bands at 693 cm ¹ , 1682 cm ¹ and 1923 cm ¹ ("urea bands") were recorded. All three bands exhibited clearly rising absorbance. No decrease in the isocyanate bands was able to be separately recorded by way of the ReactIR. A rise in viscosity was observed within the first 15 min.

Characterization:

- NCO content (wet chemically (titration), IR or chromatographically)

- Molar mass and molar mass distribution (residual monomer content, chromatographically, HPLC, GPC)

- Viscosity (phenomenologically, temperature profile and aging behavior/storage stability) Synthesis of STP-2 (prepolymer 4 + a-silane PC 1711):

In a similar manner to the reaction used for the synthesis of STP-1 , STP-2 was obtained and a satisfactory result obtained via IR measuring absorption at 1682 cm-1 .

STP 2

Scheme 6. Reaction equation of the synthesis of STP-2. Synthesis of STP-3 (prepolymer 5 + γ-silane PC 1711):

In a similar manner to the reaction used for the synthesis of STP-1 , STP-3 was obtained and a satisfactory result obtained via IR measuring absorption at 1682 cm-1 .

STP 3

Scheme 7. Reaction equation of the synthesis of STP-3. Synthesis of STP-4 (prepolymer 1 + y-silane 2 (AMMO)):

In a similar manner to the reaction used for the synthesis of STP-1 , STP-4 was obtained and a satisfactory result obtained via IR measuring absorption at 1682 cm-1 .

STP

Scheme 8. Reaction equation of the synthesis of STP-4. Synthesis of STP-5 (prepolymer 4 + γ-silane 1 B):

In a similar manner to the reaction used for the synthesis of STP-1 , STP-5 was obtained and a satisfactory result obtained via IR measuring absorption at 1 682 cm-1 .

STP 5 Scheme 9. Reaction equation of the synthesis of STP-5. Determining the NCO content:

NCO content was assessed in STP compounds via IR in order to ensure that the components used in the reaction are of sufficient safety to the end-user.

: 2 shows the IR spectra of the isocyanate Desmodur E 22 prior to and after the reaction with the aminosilane PC 171 1 . The shown product STP-1 visibly no longer shows a signal at 2290 cm ¹ , which would be a typical sign of isocyanates. It has been experimentally confirmed that the NCO content is « 0.1 %. A quantification can be carried out in a wet-chemical process by way of titration according to the DIN standard and by way of calibration using IR by the targeted reaction of isocyanate with amines.

Conclusion: STP synthesis:

Five STPs were successfully produced starting from commercially available NCO prepolymers and secondary aminosilanes. The reactions differed from an exothermic point of view and were conducted in 200 mL reactors in a controlled manner, so that up-scaling is possible. The reaction with PC 171 1 was easily controllable. Steric hindrance by the phenyl group at the amine reduces the reactivity. PC 1 1 18 is considerably more reactive, and the reaction was successfully controlled by way of cooling with the temperature control unit until the majority of the reaction heat was dissipated.

More than 1 00 cross-linking reactions were carried out. Initial cross-linking reactions were conducted solely with reacting constituents. The amount of water was optimized, and the individual STPs were compared among each other with respect to the curing behavior. In addition, the combination of the STPs and the addition of diols was examined.

Comparison of the reactivity of the STPs

7 parts of a 10% aqueous KOH solution were added to the σ-silane-based STPs 1 -3 and the y- silane-based STP-5, and curing was observed. Table 2. Comparison of the reactivity of STP-1 , 2, 3 and 5. In each case, 1 0 g of the STPs was reacted with 0.7 ml_ of a 10% aqueous KOH solution.

STP-1 and STP-3 cured in less than 1 minute to form a solid resin. After the KOH solution was added, the reactions took place so quickly that manual homogenization was not possible. STP-3 exhibited the highest curing rate. STP-2 reacted slightly more slowly and more controlled to form a homogeneously cured resin, which overall achieved higher hardness than condensed STP-1 and STP-3. In conclusion, all STPs showed acceptable curing properties after addition of water and a base under stirring.

Combination of a- and -si lanes:

The combination of different STPs serves as a control parameter for optimizing process and product parameters. In this way, reactivity, viscosity and the resulting hardness of the individual materials can be combined, and a broad range of properties can be covered. Additionally, the content of the more costly σ-silane can be reduced by substituting it to a certain degree with y- silanes. Examining the curing process of STP mixtures helps determine the reactivity of the mixtures and observe the compatibility of the materials as well as the development of synergy effects. Various combinations of STPs were assessed. For example, STP-2 and STP-5 (1 :1 ) resulted in a homogeneous resin which cured in approx. 1 minute.

Table 3. Examination of the curing of STP mixtures. A total of 10 STP mixtures were reacted, each with 0.7 mL 10 wt% KOH solution. All KOH values are provided in wt%.

STP-1 STP-2 STP-3 STP-5 tgel-like [S] tgum-like tsolid

[g] [g] [g] [g]

5 5 spontaneous 20 s 1 min

5 5 15 60 s 2 min

2.5 7.5 spontaneous 5 min -

2.5 7.5 spontaneous 2 min 5 min 2.5 7.5 spontaneous 2 min 5min

2 8 spontaneous 45 s 40 min

Examination of diols as a second reactive component:

Silanols potentially react with all compounds that contain active OH groups. In addition to water, other compounds may react with silanols. A second reactive component may increase the content of the second component and thereby influence product properties. Substituting the KOH solution with diols reduces the reaction rate (refer to Table 4).

Table 4. Examination of the curing of STP-1 with a mixture of KOH solution and diols.

Increasing the KOH concentration results in higher curing rates. The individual observed intermediate states (gel-like, tacky, gum-like and solid), however, are influenced to varying degrees. In general, the system cures more quickly at the higher KOH concentration (see Tables 4 and 5). The curing times are slower than in the experiment where no diol was added, i.e., the diols or the reduced amount of water also influence the reaction.

Table 5. Examination of the cross-linking reaction with diols. STP-1 and STP-2 were reacted with a 20% aqueous KOH solution and the diols listed below.

No. Ethylene Butanediol Water KOH T tgel-like [s] tsticks tgum-like tsoiid [min] glycol [ml_] [°C] [s]

[g]

36 0.35 - 0.35 0.07 50 spontaneous 24 2 min 10

37 0.46 - 0.23 0.05 50 spontaneous 33 - 10

38 - 0.35 0.35 0.07 50 spontaneous 15 - 8

39 - 0.46 0.23 0.05 50 spontaneous 10 25 min 90

21 - - 0.63 0.07 RT spontaneous 40 s 1 40^* 0.35 - 0.35 0.07 50 spontaneous 30 45 s 1

41 ^* 0.46 - 0.23 0.05 50 spontaneous 40 90 s 5

42^* - 0.35 0.35 0.07 50 spontaneous 24 70 s 10

43^* - 0.46 0.23 0.05 50 spontaneous 25 5 min -

22^* - - 0.7 0.07 RT 14 60 s 1.5

^* These experiments were conducted with STP-2.

Conclusion of the cross-linking experiments:

A high amount of water and KOH catalysis resulted in very quick cross-linking reactions. The STPs can be reacted in less than 1 minute to form cured resin. The σ-silane-based STPs react very quickly with aqueous KOH and can be diluted with y-silane-based STPs. The different STPs are compatible among each other. As a result, it was possible to reduce the content of σ-silane- based STP to 25%, and sufficiently rapid curing was observed.

Initial experiments in which diols were added show a considerable increase in the curing times. In the experiments, the KOH solution was replaced with the diols ethylene glycol and butanediol. The decrease in the reaction rate can be attributed to a reduced amount of water and low catalysis, although curing times remained acceptable.

Examination of formulations:

After having examined the cross-linking reactions of the reactive components, the reaction behavior of the complete formulations was examined. For this purpose, the influence of the individual constituents on reactivity and viscosity were examined. Particular importance was also attached to the homogeneity of the liquids and the CO2 binding capacity. Desired properties for easy processing, which are obtained by the materials of the present invention, are:

- Two homogeneous liquids (storage stability of the components for at least 72 h for the

prototype experiment on the machine).

- Low viscosity at room temperature for easy delivery from the storage vessels. This also

applies to cool storage rooms, such as in basements. The desired viscosity is below

2000 mPa-s at 20°C.

- Good miscibility of the component. Similar viscosities are desired for this purpose, which differ by no more than a factor.

- Good CO2 binding capacity in the depressurized machine section

- Homogeneous reaction profile: with the onset of gellation, CO2 should be metered in; to

entrap the CO2 the viscosity must quickly rise after CO2 metering.

- Minimal safety risk,

- Good haptics and no contamination of the product to be packaged, i.e. avoid or drastically reduce bleeding of components.

- No odor; avoid volatile organic compounds (VOC) Examination of homogeneous components

It was observed that the reaction rate is dependent on the amount of water and catalyst. The rate-determining step is presumed to be the hydrolysis of alkoxysilanes; the silane condensation then takes place spontaneously. In addition to the concentration of the "reactive components," the remaining formulation is also crucial. It is assumed that influence is achieved via the solubility and homogeneity of the reaction mixture or the phase compatibilization. For this reason, the components were reformulated according to polarity and hydrophilic properties. The results of these cross-linking experiments are described below. In addition, the viscosity of component 1 is lowered by the addition of the additives.

Table 6. Reaction parameters of the cross-linking reactions with more homogeneous

components. The reactions were carried out with manually mixed components, which were heated to 50^QC.

^* K1 = 85 T STP- 1, 10 T TCPP and 5 T Benzoflex; ^# K1 = 92 T STP- 1, 5 T TCPP and 3 T Benzoflex.

The reformulation resulted in an acceleration of the curing process, even though the

concentration of the reactive components was lowered. The reaction is consequently assumed to be more diffusion-controlled under the conditions that were used, i.e., accessibility of the reactants is more decisive than the concentration of the reactants.

Table 7. Observations about the cross-linking experiments (refer to Table 6).

No. tcloudy tgel-like tcream ttack tgum 5 min 10 min

[s] [s]

[s] [s] [s] 33 0 - 12 5 50 Hard rubber

34 6 12 18 27 Rubber Rubber

35 4 10 20 25

36 0 - 5 9 25 Soft rubber Soft rubber

37 4 49 53 Hard rubber Hard rubber

38 2 4 70 - - Rubber Rubber

39 5 6 8 22 42 Soft rubber

40 3 6 20 3-4 Soft rubber

min

41 0 - 8 10 20 Soft rubber

Table 8. Reaction parameters of the cross-linking reactions with more homogeneous components by substitution of PPG 2000. The reactions were carried out with manually mixed components at 50^QC.

Sample KOH Glycerol PEG Dabco Triton Water PEG

(10%) 2000 DC 193 X100 400

44 7 12 15 8 5 5

45 7 10 20 8 5 5

46 7 5 15 8 5 5 5

47 7 5 10 8 5 5 10

48 7 15 10 8 5 5

49 7 10 10 8 5 5 5

50 7 5 15 8 5 5 5 Repeat

46

51 8.75 6.25 12.5 10 6.25 6.25

52 7 5 15 8 5 5 5 Repeat

46

53 7 5 15 8 5 5 5 Repeat

46

54 7 8 17 8 5 5 Table 9. Observations about the cross-linking experiments (refer to Table 8).

Influence of the emulsifiers and surfactants:

The emulsifier and the further surfactants also have considerable influence on the dissolution behavior of the individual constituents. The formulations have a high content of PEG-based surfactants. The examinations of the influence of the emulsifier and of the associative thickeners are described below.

Table 10. Examination of the type of the emulsifier on the viscosity and homogeneity of the system. K2-0 to K2-5 represent different variants of the second component.

Substance K 2-0 K 2-1 K 2-2 K 2-3 K 2-4 K 2-5

KOH (6%) 6 parts 6 parts 6 parts 6 parts 6 parts 6 parts

2-Methyl- 5 parts 5 parts 5 parts 5 parts 5 parts 5 parts ethanolamine

Water 3 parts - - - - - PEG 2000 10 parts 10 parts 10 parts 10 parts 10 parts 10 parts

PEG 1000 5 parts 5 parts 5 parts 5 parts 5 parts 5 parts

Glycerol 7 parts 7 parts 7 parts 7 parts 7 parts 7 parts

Triton X-100 5 parts 5 parts 5 parts - - -

LIALET 111 -5.5 5 parts 2.5 parts

LIALET 111 -10 5 parts 2.5 parts

Dabco DC 193 8 parts 8 parts 8 parts 8 parts 8 parts 8 parts

Optiflo-H 7500 1 parts 4 parts - 4 parts 4 parts 4 parts

Optiflo-H 600 - - 4 parts - - -

Homogeneous? At 50°C yes At 50°C 50°C yes yes il 25°c [mPas] 171 501 368 2586 603 254 r\ 5o°c [mPas] 97 78 128 90 65 98

The type of the emulsifier can influence the homogeneity and viscosity of the system (solubility and viscosity yield of PEG 2000). Being an alkyl phenolate, the emulsifier Triton®X 100 is a substance that gives rise to concerns, and therefore it was replaced with safer emulsifiers.

Ethoxylated aliphatic alcohols are therefore preferred. The aliphatic emulsifiers LIALET 1 1 1 -5.5 and LIALET 1 1 1 -10 differ with respect to the length of the PEG chain, containing 5.5 and 10 ethylene oxide units on average, respectively, and accordingly also with respect to their hydrophilic properties. A mixture of the two components can be used to deliberately set the hydrophilic properties or the HLB value by using an appropriate ratio of the two emulsifiers.

Despite dilution of the STP-1 , reaction times were observed quickly. The most promising mixtures for component 2 (K 2-1 and K 2-5) were reacted with the lowest-viscosity mixture for component 1 . Relatively rapid curing times of approximately 10 s until a tacky state was achieved, and of 16 s to 38 s until a soft rubber-like state was formed, were observed. Despite the dilution, cured hard or brittle products were obtained, so that it is to be assumed that TEOS acts as an additional cross-linking agent.

Table 11. Reaction parameters of the cross-linking reactions with associative thickener and different emulsifiers. The reactions were carried out with manually mixed components at 50^QC. s. KOH Glyc PEG PEG Dabco Triton MAE LiALET LiALET Optiflo- Optiflo-

(6%) erol 2000 1000 DC 193 X 100 1 1 1 -10 1 1 1 -5.5 H 600 H 7500 9 6 7 10 5 8 5 5 - - - 4 0 6 7 10 5 8 5 5 - - - 4 1 6 7 10 5 8 - 5 2.5 2.5 - 42 6 7 10 5 8 - 5 2.5 2.5 - 43 6 7 10 5 8 - 5 - 5 - 44 6 7 10 5 8 - 5 5 - - 45 6 7 10 5 8 - 5 - 5 4 - 6 6 7 10 5 8 - 5 5 - 4 - 7 6 8 5 5 8 - 5 5 - 8 - 8 6 8 5 5 8 - 5 5 - 8 - 9 6 8 5 5 8 - 5 5 - 8 -

Table 12. Observations about the cross-linking experiments (refer to Table 1 1 ).

Sample [S] [s] 5 min

[s] [s] [s]

59 - - - 7 27 hard rubber-like

60 - - - 12 27 hard rubber-like

61 - - - 16 38 hard rubber-like

62 - - - 10 16 hard rubber-like

63 - - - 1 1 20 hard rubber-like

64 - - - 7 18

65 - - - 9 18 hard rubber-like

66 - - - 10 21 hard rubber-like

67 - - - 8 19 hard rubber-like

68 - - - 9 19 hard rubber-like

69 - - - 1 1 19 hard rubber-like Curing with LIALET 1 1 1 -10 is faster than with LIALET 1 1 1 -5.5. The higher hydrophilic properties of LIALET 1 1 1 -10 are assumed to result in better mixing of the components, whereby the

components become blended more quickly and therefore react more quickly. The type of associative thickener used did not show any noteworthy influence on the reactivity of the

systems.

Table 13. Composition and parameters of components 2-11 to 2-19.

No. K 2-1 1 K 2-12 K 2-13 K 2-14 K 2-15 K 2-16 K 2-17^* K 2-18 K 2-19 K 2-20 K2-21

KOH 4

6 6 6 6 5 3% 4 3% 4 3% 4 3% 4 3% 4 3% (6%) (3%)

Glycerol 8 8 8 8 5 5 5 5 5 5 5

PEG

5 5 5 5 6 7 - - - - - 2000

PEG

5 - 5 - 5 5 3 7 6 3 - 1000

PEG 400 - 5 - 5 5 - 3 8 6 8 10

Dabco

8 8 - - - - - - - - - DC 193

Niax

- - 8 8 8 10 10 8 10 10 10 L580

MAE 5 5 5 5 5 5 5 5 5 5 5

LiALET

5 5 5 5 5 5 5 5 6 6 6 1 1 1 -10

LiALET

- - - - - - - - - - - 1 1 1 -5.5

Optiflo-H

8 8 8 8 6 8 6 8 8 10 10 600

PVA 10 - - - -

Π. 430 397

Π. 150 132

P 1.14

Homoge

yes yes yes yes yes yes no yes yes yes yes neity The viscosity was successfully increased after PEG 2000, which is viscous per se, was substituted with the lower molecular weight analogs PEG 1000 and PEG 400. Reducing the amount of water (KOH solution) also increased the viscosity. In addition, the silicone surfactant from Dabco DC 193 was replaced with Niax Silicone L-580, which presumably also had a slightly positive effect on viscosity.

Table 13. Composition and parameters of components K 1 -4 to K 1 -1 1 .

No. K 1 -4 K 1 -5 K 1 -6 K 1 -7 K 1 -8 K 1 -9 K 1 -10 K 1 -1 1

STP-1 [parts] 90 85 84 80 80 80 75 80

TCPP [parts] 3 3 5 5 5 5 5 3

Benzoflex

2 2 5 5 5 3 3 2 9-88 [parts]

TEOS [parts] - 5 - - - - - -

Ethanol [parts] 5 5 - - - - - -

LIALET

- - 5 5 5 3.5 5 -

1 1 1 -5.5 [parts]

PC [parts] - - 1 5 - 8.5 12 10

D C [parts] - - - - 5 - - -

D SO - - - - - - - 5

Reactions 59, 60 61 - 66 67 68, 70, 72 69 71 , 74 73, 75 76

Π.20°C 4400 2000 - - 3193 2087

Π.25°C 3000 1400 4870 2909 2140 2258 1374

Π.50°C 700 400 1093 793 569 573 382

Homogeneity yes yes yes yes yes yes yes yes

Aging

H. 2o°c (1 d) r|. 25°c (1 d) 3395 r|. 5o°c (1 d) 728 η.25°c (3 d) 4303 2181 1531 η. sere (3 d) 894 484 388 To adapt the reactivity, homogeneity was increased, and the later mixing of components 1 + 2 was carried out by increasing the viscosity of component 2. In addition, the amount of KOH was reduced, which decreases the alkalinity and the hazard potential of the component. The additional reduction of glycerol and of the amount of water was intended to result in a uniform reaction by minimally slowing down the hydrolysis.

Components 2-18 and 2-19 showed the highest viscosities (approx.120 mPa-s @50°C and 350 mPa-s @25°C) and good reaction profiles with the new formulations for component 1. They moreover are highly likely to form long-term stable solutions or dispersions.

Table 14. Observations of cross-linking reactions 70-80.

No Composition [s] [s] [s]

70 K 1-7 + 13 25 95

K2-15

71 K1-9 + 9 16 20 42

K2-11

72 K 1-7 + 10 17 62

K2-16

73 K 1-10 + 8 16 75

K2-16

74 K1-9 + 8 13 18 71

K2-16

75 K 1-10 + 7 16 32

K2-19

76 K 1-11 + 8 11 14 100

K2-19

77 K1-9 + 8 12 18 43

K2-20

78 K1-9 + 10 15 24 95

K2-21

79 K 1-10 + 10 14 21 104 K 2-20

80 K 1 -10 + 9 13 20 80

K 2-21

Conclusion: Formulation development for the prototype foam

Several formulations were developed for foam experiments on the machine. The approach of using more homogeneous formulations had a positive effect on the curing behavior. The reaction mixture and curing process reveal a different viscosity profile compared to the initial cross-linking reactions. A cream-like and tacky state is reached considerably sooner, and a continuous rise in viscosity is observed. In some instances, a tacky reaction mixture is obtained in less than 10 s, and a rubber-like state in approx. 30 s. The fastest reactions were observed when the amount of water was increased. This increased amount of water presumably accelerates in particular hydrolysis of the alkoxysilane groups, and additionally curing overall. The addition of glycerol also has an accelerating effect.

In further steps, the viscosity was adapted in the homogeneous components. The viscosity of component 1 was reduced by adding ethanol (which is liberated during the reaction) and TEOS (which was intended to serve as an additional cross-linking agent). The viscosity of component 2 was increased via the selection of the constituents, and in further experiments additionally the influence of associative thickeners was examined.

The combination of K 1-10 and K 2-20 represents a satisfactory 2-K solution.

Table 15. Optimized formulation I

Constituent K 1 -10 Constituent K 2-20

STP-1 [parts] 75 KOH (6%) 4 (3%)

TCPP or TEP

5 Glycerol 5

[parts]

Benzoflex

3 PEG 1000 3

9-88 [parts]

TEOS [parts] - PEG 400 8

Ethanol [parts] - Niax L580 10

LIALET

5 MAE 5

1 1 1 -5.5 [parts]

PC [parts] 12 LIALET 111 -10 6

Optiflo-H 600 10 Further formulations were provided that also represent satisfactory solutions.

Table 16. Optimized formulation II, comprising the combinations of K1 -input, K1 -21 or K-22 with K2-lnput or K2-23.

^*STP-13 comprises approx. 20% propylene carbonate as a solvent.

The triethyl phosphate (TEP) replaces the TCPP as a flame retardant. The amount of TEP used may be reduced in the final foaming variations.

C0₂ loading:

The CO2 solubility of the individual components is different, and to optimize the amount of CO2 which absorb the components, the individual components have been analyzed and optimized to improve the formulation for this effect.

Table 17. CO2 loading of single materials

Volumen/Masse C0₂-Aufnahme [g] C0₂-Aufnahme [%] Destilled Water 100 mL 0.173 0.173

Propylene

100 mL/111.61 g 0.775 0.77

carbonate

MAE 100 mL/90.90 g 10.54 10.4

10% MAE solution 100 g 4.10 3.9

Polypropylene

51 g 0.18 0.35

carbonate

K 1-18 50 g 0.179 0.36

K 2-22 50 g 0.418 0.35

K 2-23 50 g 0.405 0.8

Table 18. CO2 loading of the components

The pure MAE absorbs 10.4% CO2. This results in a stoichiometry factor of 5. That is, 5 amine per CO2. The situation is different to the aqueous MAE solutions. Here, if the intake of the water remains the same, 10 g MAE now absorbs 3.85 g CO2. Regardless, the CO2 loading demonstrates that intrinsic CO2 would also play a significant and useful role in the foam in addition to the provision of external CO2.

Foam experiments:

The foam experiments were conducted using a modified PU mixing and spraying machine, including a CO2 gas supply. Additional laboratory scale experiments were carried out using hand mixing or static mixers, as required. An existing PU spray machine was adapted for delivery of the components, i.e., the delivery mechanism was adapted to fit the component ratio of 2:1 and the particular viscosities, in addition to a CO2 line. The PU mixing machine was a Duomix from Wiwa®. Other suitable devices can be identified, and adapted if required, by a person skilled in the art. C0₂ supply:

The foam is expanded using CO2 as the external and physical blowing agent. The CO2 is added by metering in gaseous form, essentially as a 3rd component. The supply of CO2 is carried out into the reacting cross-linking mixture during an intermediate stage of the cross-linking reaction. CO2 delivery is carried out at the point at which the reaction/viscosity begins to increase. The supply of CO2 is provided in a high-pressure zone, into the mixture of the two components, in the mixing chamber of the foaming device. The reaction mixture is sufficiently viscous shortly thereafter to maintain the CO2 in the cells of the foam upon entry into the low-pressure zone of the discharge device, as the foam is discharged.

Foam production:

Foams of various densities were produced on the basis of the components and methods described herein that are suitable for packaging applications. In particular, suitable foams were achieved using combinations of the components described in tables 15 and 16. Any given combination of each or any of K1 and K2 as described herein is envisaged in the present invention.

The foam is produced combining up to three different kinds of blowing agent with the cross-linking STP (in contact with water). The blowing agents employed during the examples comprise an external blowing agent, and/or chemical and physical internal blowing agents. The chemical blowing agents are carbamates, which undergo decomposition to form C02 when in contact with base. The foam formulation may therefore be described as a "2+1 " component system. The foaming occurs by bringing the two components described herein into contact with the blowing agent, which may be termed a third component.

Experimental lab scale approaches have demonstrated that foaming can take place using the internal foaming agents alone by mixing by hand, or being pressed through a static mixer, the external blowing agent provides particularly stabile foam of uniform cell size when using a converted PU mixing and spraying machine, adapted for introduction of CO2. The synthetic foams obtained are elastic foam materials with suitable densities for packaging applications.

Component properties:

For optimal performance, the foaming machine is setup according to the formulation and its components, as is required. Several physical properties of the two components are important in this regard. The key physical properties of the components described herein are described below.

1 . Viscosity and viscosity behavior of the two components

a. Two homogeneous liquids are provided as components, which are blended at a

volume ratio of 2:1 . The are 3 properties of the components that are important and have been achieved by the present invention:

i. q 2o°c≥ 2000 mPa s (for delivery from the storage vessels)

ii. QKI /

4 (similar viscosities for improved miscibility) iii. The viscosity rises quickly after blending to bind the CO2

2. Storage stability of the components

a. Two homogeneous components have been developed, which maintain their

properties for an extended time (storage stability).

b. The components are monophasic and remain liquid.

c. Aging processes do not change the viscosity (contact with water).

3. High CO2 binding capacity and CO2 solubility

a. For very low density foam, the foaming with CO2 is carried out in two stages, namely physically by way of the pressure difference, and additionally by way of the viscosity. b. Secondly, absorption and dissolution of CO2, which is then additionally liberated

during foaming, so as to achieve very low densities.

4. Homogeneous reaction profile

a. With the onset of gelation, the reaction mixture is "loaded" with CO2; the viscosity now rises further to maintain the CO2 in the depressurized part of the machine. 5. Avoidance of hazardous materials, safety risk from flammable substances

a. Ethanol and TEOS were removed from the formulation and replaced with low- viscosity components.

6. Good haptics and no contamination of the product to be packaged (bleeding); there is no tacky film on the foam surface.

7. Acceptable odor.

Conclusion of the Examples:

A prototype formulation was developed, which allows rapid curing. This formulation relies on safer components than foam systems previously disclosed and shows more uniform viscosities of the components. Numerous influencing parameters on the compatibility of the components, viscosities, and reaction rates or curing times were identified and adapted, ultimately producing a set of components that show synergistic and unexpected effects with respect to crosslinking and foam formation via an external blowing agent.

Initially, silane terminated prepolymers (STPs) were successfully produced and cross-linked. It was demonstrated that curing can take place quickly enough for a foam process using CO2 as the external blowing agent. Foam formation was subsequently obtained using a foaming pistol, providing foam of the desired properties suitable for a packaging product.

Claims

1 . Synthetic foam material comprising a crosslinked polymer network of one or more silane- terminated polymers (STP).

2. Synthetic foam material according to the preceding claim, wherein the foam material is produced by means of an external blowing agent.

3. Synthetic foam material according to the preceding claim, wherein the external blowing agent is CO2.

4. Synthetic foam material according to claim 2, wherein the external blowing agent is a gas, preferably selected from the group consisting of CO2, nitrogen and/or air, such as compressed air.

5. Synthetic foam material according to the preceding claim, wherein the gas is entrapped in the foam structure.

6. Synthetic foam material according to the preceding claim, wherein the gas is CO2 and contributes to 2-35% by weight of the foam material, preferably 5-30% by weight.

7. Synthetic foam material according to claim 2, wherein the foam material is produced by means of an internal blowing agent, or a combination of external and internal blowing agents.

8. Synthetic foam material according to any one of the preceding claims, wherein the foam material exhibits a density of 20 kg/m³ or less, preferably 12 kg/m³ or less, more preferably 10 kg/m³ or less, or more preferably of 8 kg/m³ or less.

9. Synthetic foam material according to any one of the preceding claims, wherein said foam material exhibits a cross-linked polymer network with elastic properties and/or energy absorbing properties.

10. Synthetic foam material according to any one of the preceding claims, wherein the STP component is obtained from (i) one or more aminoalkoxysilane-reactive polymeric resins and (ii) one or more aminoalkoxysilane components.

1 1 . Synthetic foam material according to any one of the preceding claims, wherein the STP component is obtained from (i) one or more NCO-Prepolymers and (ii) one or more aminoalkoxysilane components.

12. Synthetic foam material according to the preceding claim, wherein the aminoalkoxysilane component is an alpha-aminomethyl di- or tri-alkoxysilane and/or a gamma-aminopropyl di- or tri-alkoxysilane.

13. Synthetic foam material according to claim 1 1 , wherein the NCO-Prepolymer prior to reaction with an aminoalkoxysilane component exhibits an NCO-content of 15% or less, preferably less than 10%, most preferably of 4%-8%, in particular 6%, and wherein the STP component obtained by reaction of an NCO-Prepolymer with an aminoalkoxysilane component exhibits an NCO-content of less than 1 %, preferably less than 0.1 %.

14. Synthetic foam material according to claim 1 1 , wherein the NCO-Prepolymer prior to reaction with an aminoalkoxysilane component exhibits a molecular weight of 500-5000 g/mol, preferably 750-4000 g/mol, more preferably 1000 to 3000 g/mol.

15. Synthetic foam material according to any one of the preceding claims, wherein the STP component is obtained from (i) one or more NCO-functionalized alkylalkoxysilane components and (ii) one or more polymeric components with at least one OH group.

16. Synthetic foam material according to any one of the preceding claims, wherein the STP component prior to cross-linking exhibits a molecular weight of 750-8000 g/mol, preferably 1000-7000 g/mol, more preferably 2000 to 6000 g/mol.

17. Synthetic foam material according to any one of the preceding claims, wherein the STP component prior to cross-linking comprises 2-12, preferably 3-9, or 6-9, reactive alkoxysilane groups per molecule.

18. Synthetic foam material according to any one of the preceding claims, wherein the STP component prior to cross-linking comprises 2-20, preferably 4-10, reactive crosslinking sites per molecule.

19. Synthetic foam material according to any one of the preceding claims, wherein the STP component comprises one or more structures according to Formula I:

wherein

X = O or NH;

R" = a substituent of the following structure: wherein R = Alkyl, preferably methyl or ethyl, or Alkoxy, preferably OMe or OEt, wherein at least 2 R groups, preferably 3 R groups, attached to Si are Alkoxy;

R' = H, Alkyl, preferably cyclohexyl, Aryl, preferably phenyl, or R";

n = 0-6, preferably 1 -3.

20. Synthetic foam material according to any one of the preceding claims, wherein the

polymer network of one or more crosslinked silane-terminated polymer (STP)

components comprises one or more additional cross-linked polyol components.

21 . Synthetic foam material according to any one of the preceding claims, wherein the polyol component

(i) exhibits an OH-Number of 2 or more, preferably 2-5; and/or

22. Synthetic foam material according to any one of the preceding claims, comprising

additionally propylene carbonate and/or a flame retardant, such as Triethyl Phosphate (TEP) and or Tris-(1 -chloro-2-propyl)phosphate (TCPP).

23. Synthetic foam material according to any one of the preceding claims, comprising

additionally a viscosity modifier, water scavenger, such as Vinyltri(m)ethoxysilane, a cross-linking agent, such as Tetraethyl orthosilicate, and/or a plasticizer.

24. Synthetic foam material according to the preceding claim, wherein the viscosity modifier is selected from the group consisting of glycerol, polypropylene glycol and polyethylene glycol.

25. Synthetic foam material according to any one of the preceding claims, comprising

additionally a silicone surfactant, preferably a short chain siloxane backbone with one or more PEG-substituents (PEG-chains), an organic surfactant, such as an ethoxylated oxo- alcohol, such as are available from SASOL, and/or an associative thickener, such as are available from BYK.

26. Synthetic foam material according to any one of the preceding claims, comprising

additionally an agent for enhanced CO2 adsorption or capture, such as 2- methylaminoethanol.

27. Synthetic foam material according to any one of the preceding claims, comprising (% by weight): a. a polymer network of one or more crosslinked silane-terminated polymer (STP) components according to any one of claims 10 to 21 ,

at 40-70%, preferably 45-65%;

b. flame retardant, preferably TEP,

at 0.1 -5%, preferably 0.5-4%; and

c. one or more viscosity modifiers, silicone and/or organic surfactants, agents for enhanced CO2 adsorption or capture, and/or compiling products,

preferably selected from:

a silicone surfactant according to claim 25,

an organic surfactant according to claim 25, and

an associative thickener according to claim 25,

2-methylaminoethanol, at 15-45%, preferably 20-35%.

28. Kit for the production of a synthetic foam material, preferably according to any one of the preceding claims, comprising at least two components separated in two or more vessels, wherein each component is preferably present as a product blend, wherein

(i) a first vessel comprises (component 1 ) at least a fluid or solution comprising a silane- terminated polymer (STP) component according to any one of the preceding claims, and

(ii) a second vessel comprises (component 2) at least H₂0 and a catalyst, such as a base, for example KOH.

29. Kit for the production of a synthetic foam material according to the preceding claim, wherein the first vessel comprises

(i) a solvent, preferably propylene carbonate; and/or

(ii) a flame retardant, such as Triethyl Phosphate (TEP) and/or Tris(1 -chloro-2- propyl)phosphate (TCPP).

30. Kit for the production of a synthetic foam material according to the preceding claim, wherein the second vessel comprises

31 . Kit for the production of a synthetic foam material according to any one of the preceding claims, wherein at least one component comprises one or more of

(ii) a surfactant, such as a silicone surfactant according to claim 25, and/or an organic surfactant according to claim 25.

32. Kit for the production of a synthetic foam material according to any one of the preceding claims, comprising at least two components, each component preferably present as a product blend, in two or more separate vessels, wherein a first vessel comprises a solution or fluid comprising (% by weight): a. 50-90%, preferably 60-80%, silane-terminated polymer (STP); b. 0.5-30%, preferably 1 -15%, fire retardant, preferably TEP; c. 1 -10%, preferably 2-6%, organic surfactant, such as according to claim 25. d. 5-20%, preferably 10-15%, solvent and/or a viscosity reducing agent, preferably propylene carbonate; wherein a. to d. add to 100%, and a second vessel comprises a solution or fluid comprising: e. 2-20%, preferably 4-16%, catalyst, preferably a base, such as KOH solution in water; f. 20-60%, preferably 25-50%, viscosity modifiers, selected from the group

consisting of glycerol, polypropylene glycol and polyethylene glycol; g. 20-60%, preferably 25-50%, one or more surfactants, such as a silicone

surfactant and/or an organic surfactant according to Claim 25 and additionally an associative thickener as described under claim 25, and/or h. 0-20%, preferably 5-15%, of an agent for enhanced CO2 adsorption or capture, preferably 2-methylaminoethanol; wherein e. to h. add to 100%.

33. Kit for the production of a synthetic foam material according to any one of the preceding claims, wherein at least one of the at least two components, each component preferably present as a product blend, is loaded with CO2.

34. Kit for the production of a synthetic foam material according to any one of the preceding claims, wherein the at least two components comprise less than 0.1 % NCO-content.

35. Kit according to any one of the preceding claims, wherein the Kit is present in the form of a foam pouring unit or comprises means for pouring, such as a hand-held pneumatically driven discharge gun, pouring gun, pourer or pouring nozzle.

36. Method for production of a synthetic foam material according to any one of the preceding claims, comprising: a. bringing a fluid or solution comprising a silane-terminated polymer (STP) component according to any one of the preceding claims (component 1 ) into contact with a solution comprising at least H₂0 and a catalyst, such as KOH (component 2); b. Mixing the components 1 and 2 under conditions suitable for chain growth and/or for polymer network formation via cross-linking; c. Contacting said mixture with an external blowing agent at an intermediate stage of polymer network formation; and d. Discharge or pouring of said mixture as a foam according to the synthetic foam material according to any one of the preceding claims.

37. Method according to the preceding claim, wherein the external blowing agent is CO2 gas.

38. Method according to any one of the preceding claims, wherein the external blowing agent is liquid CO2.

39. Method according to any one of the preceding claims, wherein the synthetic foam material is produced by means of a combination of external and internal blowing agents.

40. Method according to the preceding claim, wherein the internal blowing agent is

outgassing of gas, such as CO2, from a solution, or enables production of a gas, such as CO2, from a reactive component through the input of chemical, kinetic or thermal energy, wherein the internal blowing agent is preferably selected from CO2 (saturated

components), (inorganic and/or organic) carbamates, such as the adduct of

Methylaminoethanol and CO2, respectively, low boilers, such as propane and/or butane, or hydrofluorocarbons, preferably each with 1 -5 carbon atoms.

41 . Method according to any one of the preceding claims, wherein the synthetic foam material is at least partially polymerized and exhibits elastic properties within 3 minutes after foam discharge, preferably within 1 minute after foam discharge.

42. Method according to any one of the preceding claims, wherein the synthetic foam material exhibits an least partially crosslinked network and exhibits the strength and mechanical stability to resist a mechanical strain or load typically encountered during transport or storage of a cardboard container within 60 minutes after foam discharge, preferably within 30 minutes after foam discharge, more preferably 10 minutes after foam discharge.

43. Method for production of a synthetic foam material according to any one of the preceding claims, wherein:

(i) component 1 is according to the first component of any one of claims 28-35, (ii) component 2 is according to the second component of any one of claims 28-35, and

(iii) the components 1 and 2 are added at a ratio of 10:1 to 1 :1 , preferably 3:1 to 1 :1 , more preferably 2:1 .

44. Method for production of a synthetic foam material according to any one of the preceding claims, wherein the method is carried out between 15 and 80 deg C, preferably between 20 and 60 deg C, for example at ambient temperature.

45. Method for production of a synthetic foam material according to any one of the preceding claims, wherein discharge of the foam occurs using a hand-held pneumatically driven discharge gun, pouring gun, pourer or pouring nozzle.

46. Method for production of a synthetic foam material according to any one of the preceding claims, wherein the ratio of the mixture of components 1 and 2 according to claim 34 b. to gas is 50:1 to 3:1 by weight.

47. Synthetic foam material obtainable by the method according to any one of the preceding claims.

48. Use of a synthetic foam material according to any one of the preceding claims or the method for producing a synthetic foam material of any one of the preceding claims as a protective packaging for an item to be encompassed by said foam.

49. Use of a synthetic foam material according to the preceding claim, wherein the foaming mixture is poured into a closable bag or foil in order to avoid direct contact between the foam and item of interest.

50. Use of a synthetic foam material according to any one of the preceding claims or the method for producing a synthetic foam material of any one of the preceding claims for protective packaging, wherein said use comprises direct injection of the foam material, such that the foam takes on the shape of an item to be encompassed by said foam.