WO2018203035A1

WO2018203035A1 - Compositions and methods

Info

Publication number: WO2018203035A1
Application number: PCT/GB2018/051077
Authority: WO
Inventors: John Adamson
Original assignee: Lankem Ltd.
Priority date: 2017-05-05
Filing date: 2018-04-25
Publication date: 2018-11-08
Also published as: GB2562172A; EP3622001A1; GB2562172B; GB201707211D0; GB201807325D0

Abstract

Apolymerof formula (I): (I) wherein P is a polyalkyleneiminebackbone; A is a carbonylalkyleneoxy group; each Z is independently H or CR1R2CR3R4OH, provided that at least one Z is not hydrogen; wherein each of R1, R2, R3and R4 is independently selected from hydrogen or an optionally substituted hydrocarbyl group; each x is at least 1; and y is a number less than or equal to the number of reactive amine groups in P.

Description

Compositions and methods

The present invention relates to improved polymeric compounds, to compositions comprising the same, and to methods and uses relating thereto. In particular, the present invention relates to functionalised polyalkyleneimine polymers, and to the use of such compounds, especially as dispersants.

Dispersants are used to separate particulates and distribute these in a medium, for example to facilitate distribution of solid components in a liquid. Dispersants are used in a variety of industries to assist the distribution of solid materials, for example in the fields of paints, inks, fuels, agrochemicals, oilfield, lubricants, plastics and personal care.

The present invention finds particular utility in relation to the dispersion of pigments. The present invention relates to the use of polyalkyleneimine polymers as dispersants. Some compounds of this type are known in the art as dispersants.

For example, US6197877B1 discloses a polyalkyleneimine polymer which carries at least two polyoxyalkylenecarbonyl chains which are end-capped with a carboxylic acid terminating group.

US2003/0027873A1 describes dispersants formed by reacting a polyamine or a polyimine with a lactone and glycolic acid in the presence of a polymerisation terminating compound, for example a carboxylic acid.

However there is a continuing need for new dispersant compounds which will exhibit different properties to existing compounds.

According to a first aspect of the present invention, there is provided a polymer of formula (I):

(I) wherein P is a polyalkyleneimine backbone;

A is a carbonylalkyleneoxy group;

each Z is independently H or CR R²CR³R⁴OH, provided that at least one Z is not hydrogen; wherein each of R , R², R³ and R⁴ is independently selected from hydrogen or an optionally substituted hydrocarbyl group; each x is at least 1 ; and

y is a number less than or equal to the number of reactive amine groups in P.

P is a polyalkyleneimine backbone. By polyalkyleneimine backbone, we mean that the polymer has a backbone structure based on a polyalkyleneimine. The polymer of the present invention includes a backbone structure comprising a polyalkyleneimine and moieties [(A)_x-Z] which are appended to the backbone structure.

The polyalkyleneimine may be represented stoichiometrically by the structure of formula (II):

(ll) wherein m is the number of repeating units in the backbone. The skilled person, however, will appreciate that branching within the monomer and throughout the polymer may occur. Preferred monomers are straight chain monomers.

Suitable polyalkyleneimines include those prepared from monomers having from 1 to 10, preferably from 2 to 5, more preferably 2 to 3 carbon atoms in the alkylene chain. Preferred polyalkyleneimines are polypropyleneimine and polyethyleneimine. Polyethyleneimine (hereinafter "PEI") is especially preferred.

Suitable compounds and methods for use in the preparation of polyalkyleneimines will be known to the skilled person. For example, PEI may be produced by cationic ring opening polymerisation of aziridine monomers.

PEI may be represented stoichiometrically by the structure of formula (III):

(III) wherein m is the number of repeating units present in the polyalkyleneimine backbone.

However the skilled person will appreciate that commercial sources of PEI typically contain branching and the above should not be considered a linear representation of the compound. Thus the polymer will include primary, secondary and tertiary amino groups. The extent of branching depends on reaction conditions used in the preparation of PEL Linear PEI contains a dominant proportion of secondary amino groups. Branched PEI contains a mixture of primary, secondary and tertiary amino groups. m is suitably from 1 to 10000, preferably from 50 to 5000, more preferably from 100 to 2000, more preferably from 200 to 1000, more preferably from 200 to 600.

Suitably, P has a weight average molecular weight of from 10000 to 100000, suitably from 2000 to 50000, suitably from 5000 to 30000.

In some embodiments, P has a weight average molecular weight of from 1000 to 30000, preferably 23000 to 27000, for example 25000. In some embodiments, P has a weight average molecular weight of from 5000 to 15000, preferably 8000 to 12000, for example 10000.

Each A is a carbonylalkyleneoxy group. Each A is suitably a carboxyalkyleneoxy group of formula CORO, wherein R is an optionally substituted alkylene group. Preferably, R is an unsubstituted alkylene group. Each A is preferably CO(CH₂)_nO, wherein n is preferably from 1 to 10, preferably from 2 to 6, more preferably from 3 to 5, more preferably 3 or 5, most preferably 5. A is preferably a carbonylpentyleneoxy group or a carbonylpropyleneoxy group. In most preferred embodiments, A is a carbonylpentyleneoxy group.

Each A may be the same or different. In each polyester chain (A)_x, each A may be identical or the chain may include a mixture of monomers. Each x is on average from 1 to 100, suitably from 6 to 50, suitably from 8 to 30, preferably from 10 to 20.

In some embodiments each x is on average 10. In some embodiments each x is on average 20.

The polymer of the present invention includes a number of polyester units [(A)_x-Z]. The skilled person will appreciate that x will vary from chain to chain and each polymer molecule will contain multiple polyester chains which are typically of different lengths. References herein to a value of x are to average (mean) values thereof.

Each Z is independently hydrogen or CR R²CR³R⁴OH, provided that at least one Z is not hydrogen.

Each of R , R², R³ and R⁴ is independently selected from hydrogen or an optionally substituted hydrocarbyl group. The optionally substituted hydrocarbyl group may include a substituent within the chain. Thus each of R , R², R³ and R⁴ may independently include an ether OR or an ester COOR moiety.

Suitably each of R , R², R³ and R⁴ is independently hydrogen or an optionally substituted hydrocarbyl group comprising from 1 to 50, preferably from 2 to 40, more preferably from 4 to 30, most preferably from 6 to 25 carbon atoms.

Preferably each of R , R², R³ and R⁴ is independently hydrogen or a moiety comprising an optionally substituted alkyl, alkenyl or aryl group. Preferably, each of R , R², R³ and R⁴ is independently hydrogen or an optionally substituted alkyl or aryl group, preferably hydrogen or an optionally substituted alkyl group.

Suitable substituents include acyl groups and epoxy groups. In some embodiments there may be an oxygen substituent within the alkyl chain to provide an ether group or ester group.

In preferred embodiments, at least one of R , R², R³ and R⁴ is not hydrogen.

In preferred embodiments, at least one of R and R² is hydrogen.

In some embodiments, R is hydrogen or an optionally substituted alkyl group having from 1 to 50, preferably from 8 to 20, more preferably from 10 to 15, most preferably from 12 to 14 carbon atoms.

Preferably R is hydrogen.

R² is suitably hydrogen or an optionally substituted alkyl group. In some embodiments R² is an optionally substituted alkyl group having from 1 to 50, preferably from 8 to 20, more preferably from 10 to 15, most preferably from 12 to 14 carbon atoms.

In some embodiments, R is hydrogen and R² is hydrogen. In some preferred embodiments, at least one of R³ and R⁴ is an optionally substituted alkyl group including from 1 to 50, preferably from 8 to 20, more preferably from 10 to 15, most preferably from 12 to 14 carbon atoms. In preferred embodiments, one of R³ and R⁴ is hydrogen.

In some embodiments, R³ is an optionally substituted alkyl group having from 1 to 50, preferably having from 8 to 20, more preferably from 10 to 15, most preferably from 12 to 14 carbon atoms, and R⁴ is hydrogen.

In some embodiments, R³ is a group of formula -CH₂OR wherein R is an optionally substituted alkyl or alkenyl group, preferably having from 1 to 50, preferably from 8 to 20, more preferably from 10 to 15, most preferably from 12 to 14 carbon atoms, and R⁴ is hydrogen. In some embodiments, R⁴ is hydrogen and R³ is a group of formula R^aCOOR^b wherein R^a is an optionally substituted alkylene or alkenylene group, preferably having 1 to 16, preferably 2 to 12 carbon atoms; and R^b is an optionally substituted alkyl or alkenyl group, preferably having from 1 to 16, preferably from 2 to 12 carbon atoms. In some embodiments, R² is hydrogen, R⁴ is hydrogen and each of R and R³ is an optionally substituted hydrocarbyl group, preferably having 1 to 20, suitably 4 to 16 carbon atoms.

In some embodiments, R , R² and R⁴ are hydrogen and R³ is selected from a phenyl, benzyl, and alkyl group having 1 to 50, preferably 8 to 20 carbon atoms, and an ether group OR wherein R is an alkyl or alkenyl group having 1 to 50, preferably 8 to 20 carbon atoms.

In one embodiment, R , R² and R⁴ are all hydrogen and R³ is a group -CH₂0(CI-l2)nCI-l3 wherein n is from 1 to 24, suitably 4 to 20, preferably 6 to 18, more preferably 10 to 16. In some embodiments, R is hydrogen; R³ is hydrogen; R² is hydrogen or an optionally substituted hydrocarbyl group, preferably having 1 to 20, suitably 4 to 16 carbon atoms; and R⁴ is an optionally substituted hydrocarbyl group, preferably having 1 to 20, suitably 4 to 16 carbon atoms. The optionally substituted hydrocarbyl group (R² or R⁴) may be an optionally substituted alkyl or alkenyl group; an ester containing group of formula R^aCOOR^b wherein R^a is an optionally substituted alkylene or alkenylene group, and R^b is an optionally substituted alkyl or alkenyl group; or an ether containing group of formula -CH₂OR wherein R is an optionally substituted alkyl or alkenyl group. In some embodiments, R is hydrogen; R³ is hydrogen; R² is hydrogen or an optionally substituted alkyl or alkenyl group, preferably having 1 to 20, suitably 4 to 16 carbon atoms; and R⁴ is selected from:

an optionally substituted alkyl or alkenyl group, preferably having 1 to 20, suitably 4 to 16 carbon atoms;

an ester containing group of formula R^aCOOR^b wherein R^a is an optionally substituted alkylene or alkenylene group, preferably having 1 to 16, preferably 2 to 12 carbon atoms and R^b is an optionally substituted alkyl or alkenyl group, preferably having from 1 to 16, preferably from 2 to 12 carbon atoms; and

an ether containing group of formula -CH₂OR wherein R is an optionally substituted alkyl or alkenyl group, preferably having from 1 to 50, preferably from 8 to 20, more preferably from 10 to 15, most preferably from 12 to 14 carbon atoms. y is a number less than or equal to the number of reactive amine groups in P.

P may suitably be represented stoichiometrically as [CnH₂nNH]_m, preferably as [CH₂CH₂NI-I]_m, wherein m is the number of repeating units (i.e. monomers) in the backbone. Although P may be branched, each repeating unit of the polyalkyleneimine P includes on average one NH bond. However the polyalkyleneimine will typically include at least some branching. Thus it will contain a mixture of primary, secondary and tertiary amino groups. The tertiary amine groups will be unable to react further with a moiety to form a side chain. Each secondary amino group can form one further bond. Each primary amino group can in theory form two further bonds. However the skilled person will appreciate that once a primary amine has been acylated the remaining NH group will no longer be reactive.

The maximum number of bonds that P can form with side chain moieties is equal to the number of reactive amine groups in P.

By "number of reactive amine groups", we mean to refer to the total number of primary and secondary amine groups.

The polymer of the invention includes a backbone P and units [(A)_x-Z] appended to the backbone, y is the number of units [(A)_x-Z] appended to the backbone. Thus y is less than the total number of primary and secondary amine groups. y may be expressed as a percentage of the total number of reactive amine groups. Where y is expressed as a percentage of the total number of reactive amine groups, y is suitably at least 50%, preferably at least 60%, more preferably at least 70%, most preferably at least 80%. Each unit Z is independently hydrogen or CR R²CR³R⁴OH.

The unit CR R²CR³R⁴OH is suitably formed by the reaction of an epoxide with a precursor compound of formula I in which each Z is H. In the polymer of the first aspect, at least 20% of groups Z are CR R²CR³R⁴OH, preferably at least 30%, more preferably at least 40%.

In preferred embodiments, a majority of groups Z are CR R²CR³R⁴OH. Suitably at least 50%, preferably at least 60% of groups Z are CR R²CR³R⁴OH.

Preferably from 75 to 100%, more preferably from 80 to 100%, most preferably from 90 to 100% of groups Z are CR R²CR³R⁴OH. Thus, the polymer of the present invention suitably comprises a polyalkyleneimine backbone having multiple chains of carbonylalkyleneoxy repeating units appended thereto to form polyester units, each polyester chain having a CR R²CR³R⁴OH or a hydrogen terminating group. The skilled person will appreciate that polymers comprise a mixture of compounds and the above definitions of m, y and Z refer to the average (mean) value for each of these.

The polymer of the present invention can be prepared by any suitable means. In preferred embodiments, the polymer of the present invention is obtained by reacting a polyalkyleneimine with a lactone to build a polyester, and reacting the resultant polyester with an epoxide.

According to a second aspect of the present invention, there is provided a method of preparing a polymer of formula (I):

(I) wherein P is a polyalkyleneimine backbone; A is a carbonylalkyleneoxy group;

each Z is independently H or CR R²CR³R⁴OH, provided that at least one Z is not hydrogen; wherein each of R , R², R³ and R⁴ is independently selected from hydrogen or an optionally substituted hydrocarbyl group;

each x is at least 1 ; and

y is a number less than or equal to the number of reactive amine groups in P;

the method comprising the steps of:

(a) providing a polyalkyleneimine;

(b) reacting the polyalkyleneimine with an optionally substituted lactone; and

(c) reacting the material obtained in step (b) with an optionally substituted epoxide.

Preferred features of the second aspect are defined in relation to the first aspect.

Suitable polyalkyleneimines for use in step (a) of the method of the second aspect are as defined in relation to the first aspect. Most preferably, the polyalkyleneimine is a polyethyleneimine.

In step (b), a polyalkyleneimine is reacted with an optionally substituted lactone. The reaction in step (b) provides unit A.

The optionally substituted lactone reacted in step (b) provides unit A in the polymer of formula (I) and the definitions of this unit referred to in the first aspect apply to the second aspect.

Preferably A is CO(CH₂)_n O and the lactone is:

wherein n is preferably from 1 to 10, preferably from 2 to 6, more preferably from 3 to 5, more preferably 3 or 5, most preferably 5.

Preferred lactones include ε-caprolactone and γ-valerolactone. ε-caprolactone is especially preferred.

In some embodiments a single lactone is reacted with the polyalkyleneimine in step (b). In such embodiments each group A in the resultant polymer is the same. In some embodiments step (b) may involve reacting the polyalkylene imine provided in step (a) with a mixture of two or more lactones. In such embodiments the resultant polymer A will include two or more different units A. The arrangement of these within the resultant polymer will depend on whether the two or more different lactones are reacted together in a mixture or reacted stepwise in a sequential manner. The relative reactivities of the lactones used will also have an effect on the arrangement of groups A in the resultant polymer, as will the reactivity of the amine groups in the polyalkylene imine backbone (e.g. ratio of primary, secondary and tertiary amine moieties) and steric effect. The ratio of lactone to polymer used in step (b) may be adjusted depending on the number of reactive amine groups in the polymer, and the desired extent of polymerisation.

Initially, the lactone will react directly with the amine functional groups on the polymer backbone. Subsequent lactone molecules may react with further amine groups on the polymer backbone or they may react with the terminal hydroxy groups formed on opening the lactone.

Suitably, step (b) is carried out at a temperature of from 50 to 300 °C, preferably from 60 to 250 °C, more preferably from 80 to 200 °C, most preferably from 120 to 180 °C. Suitably, step (b) is conducted in the presence of a catalyst. Any suitable catalyst may be used. Suitable catalysts include Lewis acid catalysts. Suitable catalysts include tin salts. Suitable catalysts include tin (II) salts, for example tin (II) octoate, dibutyltin dilaurate, dibutyltin dichloride. Suitable catalysts include tin (IV) salts, for example SnCI₄; titanium complexes, for example tetrabutyltitanate and tetraisopropyltitanate; and aluminium complexes, for example tris(acetylacetonato)aluminium and (porphinato)aluminium). One preferred catalyst is dibutyltin dilaurate.

Suitable optionally substituted epoxides for use in the method of the second aspect are compounds of formula

wherein R , R², R³ and R⁴ are as defined in relation to the first aspect. Suitable epoxides include alkylene oxides, glycidyl ethers, epoxidised fatty acids, and derivatives thereof. Some preferred epoxides include glycidyl ethers such as C12 to C14 glycidyl ether and glycidyl 2-methylphenyl ether; and epoxidised fatty acid esters such as epoxidised 2-ethylhexyl soybean oil fatty acid ester and epoxidised methyl soybean oil fatty acid ester. Suitable epoxidised fatty acid esters include methyl soybean oil fatty acid ester and 2- ethylhexyl soybean oil fatty acid ester.

In step (c) an epoxide is added to the mixture obtained in step (b). The mixture obtained at the end of step (b) comprises a compound of formula P-[(A)_X-H]_y i.e. a compound or formula (I) in which each Z is hydrogen.

A is suitably CO(CH₂)_nO and thus each chain appended to the polymeric backbone after step (b) terminates in an OH group. This OH group reacts with the epoxide. Titration may be carried out following step (b) to determine the number of reactive OH moieties.

Suitably, the epoxide is added in an amount of at least 0.5 molar equivalents per mole of free OH in the product obtained in step (b), suitably from 0.6 to 1 .1 molar equivalents.

Step (c) may be carried out in the presence of a catalyst. Any suitable catalyst may be used. In some embodiments the catalyst is a base. Examples of suitable base catalysts include sodium hydroxide, potassium hydroxide, sodium methoxide, tributylamine and tripropylamine. In some embodiments the catalyst is a Lewis acid. An example of a suitable Lewis acid catalyst is boron tetrafluoride. Others will be known a person skilled in the art.

Suitable reaction conditions (eg. temperature) for step (c) will depend on the particular catalyst selected. The adaption of the conditions is within the competence of the person skilled in the art.

Suitably, at least 30%, preferably at least 40%, preferably at least 50%, more preferably at least 60%, for example at least 75% of the terminal OH groups of the polyester formed in step (b) are reacted with the epoxide in step (c). Suitably up to 100%, preferably up to 90% of the terminal OH groups of the polyester formed in step (b) are reacted with the optionally substituted epoxide in step (c).

The polymer of the present invention is suitably provided in the form of a solid. The polymer may be provided as a block, drop or film. Following step (c) the resultant polymer may be left to cool to room temperature or transferred to a cooling surface.

In some embodiments, the polymer of the present invention is provided as a paste or a viscous liquid.

The polymer of the present invention has utility in a number of areas, including as dispersants, especially as dispersants for pigments. According to a third aspect of the present invention, there is provided a composition comprising a polymer of formula (I):

(I)

wherein P is a polyalkyleneimine backbone;

A is a carbonylalkyleneoxy group;

each x is at least 1 ; and

y is a number less than or equal to the number of reactive amine groups in P;

and one or more further components.

The amount of polymer present in the composition will depend on the intended use of the composition and the presence of other components.

In some embodiments, the third aspect provides a composition comprising a polymer of the first aspect and diluent or carrier. In some embodiments, suitable diluents include polar and apolar organic solvents, water and oils.

In some preferred embodiments, suitable diluents comprise one or more resins and one or more solvents.

Suitable resins for use herein include UV curable resins, for example phenoxyethyl acrylate, phenol 4 EO acrylate, nonylphenol 4 EO acrylate, hexamethylene diacrylate, bisphenol A (4EO) diacrylate, tripropylene glycol diacrylate (TPGDA), neopentylglycol, dipropoxylated, diacrylate, dipropyleneglycol diacrylate, trimethylolpropane triacrylate, trimethylolpropane propoxylated triacrylate, trimethylolpropane ethoxylated, triacrylate, glycerol propoxylated triacrylate and ethoxylated pentaerytritol tetraacrylate. Suitable solvents for use herein include glycol ether esters, for example propylene glycol methyl ether acetate esters (for example n-butyl acetate and ethyl acetate); ketones, for example 2-butanone; aromatic hydrocarbon solvent, for example naphtha, 1 ,2,4- trimethylbenzene, xylene and mesitylene; and alcohols, for example n-butanol and isobutanol; lactones, for example butyrolactone; and glycol ethers, for example phenoxy ethanol.

The polymer of the present invention may be obtained in solid form. In some embodiments the polymer may be mixed with a solvent or diluent to provide a liquid, for example a low viscosity liquid. The inventors have found that providing the polymer as a low viscosity liquid improves ease of handling.

In some embodiments, the polymer of the present invention is provided as a liquid having a viscosity of from 100 to 25000 centipoise, suitably from 100 to 5000 centipoise, preferably 100 to 1000 centipoise. In some embodiments the third aspect of the present invention may provide a concentrated composition of the polymer of the first aspect.

This may be diluted as appropriate to provide the desired final concentration of polymer depending on the intended application.

In some embodiments, the composition of the third aspect may comprise a polymer of the first aspect and a pigment. Any suitable pigment may be included. Suitable pigments for use herein include inorganic and organic pigments. Suitable classes of organic pigments for use herein include alizarin, azo-pigments (for example yellow, orange and red colour range), phthalocyanine (for example blue and green colour range) and quinacridone (for example red-violet). Examples of suitable organic pigments for use herein include pigment blue 15:6; pigment red 57.1 , pigment red 48:1 and pigment red 48:3; pigment yellow 14, pigment yellow 17, pigment yellow 83 and pigment yellow 74; pigment green 7; pigment violet 23; and pigment orange 13 and pigment orange 34.

Suitable inorganic pigments for use herein include titanium dioxide, carbon black (for example carbon black 7 and carbon black 430), iron oxide, chromium pigments and ultramarine blue. Suitably the inorganic pigment for use herein is selected from titanium dioxide, conductive carbon black, graphene, carbon black (for example carbon black 7 and carbon black 430), iron oxide, chromium pigments and ultramarine blue. The amount of pigment present in the composition will depend on the nature of the pigment and the intended use of the composition.

The amount of pigment present in the composition of the third aspect may vary depending on the intended application. In some embodiments it is present in an amount of from 0.001 to 60 wt%. In some embodiments the pigment is present in the composition in an amount of from 0.001 to 40 wt%. In some embodiments the pigment may be present in the composition in an amount of from 0.001 to 20 wt%.

The pigment may suitably have a particle size of from 0.001 to 50 microns, suitably from 0.05 to 20 microns, for example from 0.01 to 5 microns. However, the skilled person will appreciate that the particle size may vary depending on the application in which the composition will be used.

In some embodiments, the composition of the third aspect may comprise a polymer of the first aspect and graphene. Graphene may function as a pigment as mentioned above. Alternatively and/or additionally graphene may enhance one or more other properties of the composition of the third aspect and/or a product comprising such a composition, for example conductivity, strength or light absorbency. The composition of the third aspect may further comprise one or more surfactants. Any suitable surfactant may be used, for example anionic, cationic, zwitterionic and/or non-ionic surfactants. Suitable surfactants will depend on the nature of the composition and will be known to the person skilled in the art. The composition of the third aspect may further comprise one or more co-dispersants. Any suitable co-dispersant may be used and suitable compounds will be known to those skilled in the art.

The polymer of the present invention and the co-dispersant may exhibit synergistic dispersancy performance. The co-dispersant compound may be effective as a dispersant when used alone. In some embodiments the co-dispersant may not independently provide effective dispersancy but may enhance the performance of the polymer as a dispersant when used in combination with it. Suitable co-dispersants will depend on the nature of the composition and the intended use thereof.

Such co-dispersants are known in the art as synergists. The present invention encompasses the use of the polymer of the first aspect in combination with one of these known synergists.

The composition of the third aspect may be an ink, paint, personal care, agrochemical, oilfield, lubricant or fuel composition.

In some embodiments, the composition of the third aspect is an ink composition. In such embodiments, the composition suitably comprises from 1 to 30 wt% of a pigment, from 5 to 100 wt% (by weight of pigment) of a polymer of formula (I), and one or more further components. Such further components will be known to the person skilled in the art and include, for example, resins, pH modifiers, humectants, binders, solvents, antifoaming agents, surfactants, biocides and rheology modifiers.

In some embodiments, the composition of the third aspect is a paint composition. In such embodiments, the composition suitably comprises from 0.01 to 30 wt% of a pigment, from 5 to 100 wt% (by weight of pigment) of a polymer of formula (I), and one or more further components. Such further components will be known to the person skilled in the art and include, for example, binders, extenders, solvents, silicones, rheology modifiers, UV stabilisers, catalysts, fillers, driers, anti-settling agents and biocides.

In some embodiments, the composition of the third aspect is an agrochemical composition. In such embodiments, the composition suitably comprises from 5 to 50 wt% of an agrochemically active ingredient, from 2 to 30 wt% (by weight of agrochemically active ingredient) of a polymer of formula (I), and one or more further components. Such further components will be known to the person skilled in the art and include, for example, binders, plant nutrients, surfactants, oil soluble bases, carriers, mineral clays, stabilisers and adjuvants. In some embodiments, the composition of the third aspect is a coating composition. In such embodiments, the composition suitably comprises from 0.1 to 30 wt% of a pigment, from 5 to 100 wt% (by weight of pigment) of a polymer of formula (I), and one or more further components. Such further components will be known to the person skilled in the art and include, for example, binders, extenders, solvents, silicones, rheology modifiers, UV stabilisers, catalysts, fillers, driers, anti-settling agents and biocides.

In some embodiments, the composition of the third aspect is a coating composition comprising graphene. In such embodiments, the composition suitably comprises from 0.1 to 15 wt% of graphene, from 5 to 100 wt% (by weight of pigment) of a polymer of formula (I), and one or more further components. Such further components will be known to the person skilled in the art and include, for example, binders, extenders, solvents, silicones, rheology modifiers, UV stabilisers, catalysts, fillers, driers, anti-settling agents and biocides.

In some embodiments, the composition of the third aspect is a masterbatch composition. In such embodiments, the composition suitably comprises from 15 to 65 wt% of a pigment, from 5 to 100 wt% (by weight of pigment) of a polymer of formula (I), from 35 to 85 wt% of a carrier resin and optionally one or more further components. The use of masterbatches is common in the polymer industry and will be well known to the person skilled in the art. The selection of a suitable carrier resin will depend on the nature of the pigment and the intended use of the masterbatch but will be within the competence of the skilled person.

In some embodiments, the composition of the third aspect may be a composite composition. In such embodiments, the composition suitably comprises from 0.1 to 15 wt% of a pigment, from 5 to 100 wt% (by weight of pigment) of a polymer of formula (I), and at least one further material having a different physical and/or chemical properties to the pigment and/or the polymer of formula (I). In some embodiments, the composition of the third aspect is a personal care composition. In some embodiments, the composition of the third aspect is an oilfield composition. In some embodiments, the composition of the third aspect is a lubricant composition.

In some embodiments, the composition of the third aspect is a fuel composition.

According to a fourth aspect of the present invention, there is provided the use of a polymer of formula (I):

(I)

wherein P is a polyalkyleneimine backbone; A is a carbonylalkyleneoxy group;

each x is at least 1 ; and

y is a number less than or equal to the number of reactive amine groups in P;

as a dispersant.

The polymer of the present invention may find particular utility as a dispersant in the fields of inks, paints, personal care, agrochemicals, oilfields, lubricants and fuels.

According to a fifth aspect of the present invention, there is provided the use of a polymer of formula (I):

wherein P is a polyalkyleneimine backbone;

A is a carbonylalkyleneoxy group;

each x is at least 1 ; and

y is a number less than or equal to the number of reactive amine groups in P;

to provide a synergistic effect when used in combination with a co-dispersant.

The invention will now be further described with reference to the following non-limiting examples.

Examples

Example 1 - preparation

In the examples MW refers to the weight average molecular weight of the starting polyethylene imine. Polymers of the invention were prepared according to the following procedure, using the specific components as defined in Table A.

Polyethylene imine (PEI) and ε-caprolactone were reacted in the presence of a dibutyltin dilaurate catalyst (0.05 g) under nitrogen at 150°C for approximately 8 hours, until the content of unreacted ε-caprolactone was reduced to <2.0%. The intermediate obtained from this reaction was an amber liquid which solidified on cooling to room temperature. The amine and hydroxyl values of this intermediate were determined. The intermediate (200 g) was then reacted with an epoxy compound (sufficient to theoretically cap X % of the hydroxyl groups) in the presence of a tributylamine catalyst (0.15 g) at 120°C, until Y % of the available epoxy groups had reacted, to provide a polymer of the invention.

Table A

Polymer PEI (g, ε-capro- Amine value of Hydroxyl value Epoxy X Y

MW) lactone intermediate of intermediate compound (%) (%)

(g) (mg KOH/g) (mg KOH/g) (g)

1 28.3g, 271 .7g 53 45 epoxidised 2- 75 >65

MW ethylhexyl

10,000 soybean oil fatty acid ester (49.1 g)

2 28.3g, 271 .7g 53 45 epoxidised 75 >65

MW methyl

10,000 soybean oil fatty acid ester (37.3g)

3 28.3g, 475.6 g 37 20 C12-C14 50 >90

MW glycidyl ether

10,000 (10.1 g)

4 28.3g, 475.6 g 37 20 C12-C14 75 >90

MW glycidyl ether

10,000 (15.0g)

5 28.3g, 475.6 g 37 20 C12-C14 100 >90

MW glycidyl ether

10,000 (20.0g)

6 28.3g, 384.8g 38 35 glycidyl 2- 75 >90

MW methylphenyl

25,000 ether (16.9g)

7 20.5g, 279.5g 36 35 C12-C14 75 >90

MW glycidyl ether

25,000 (26.3g) 23.1 g, 276.9g 53 45 epoxidised 75 >65

MW methyl

10,000 soybean oil fatty acid ester (33.8g)

28.3g, 271 .7g 52.8 45 C12-C14 75 >90

MW glycidyl ether

10,000 (33.8g)

20.5g, 279.5g 36 35 C12-C14 75 >90

MW glycidyl ether

25,000 (35.0g)

23.1 g, 276.9 53 45 epoxidised 2- 75 >65

MW ethylhexyl

10,000 soybean oil fatty acid ester (33.8g)

Evaluation Some of the polymers obtained in the preparation examples were assessed to demonstrate their effectiveness as dispersants in pigment compositions and UV-curable pigment compositions.

The pigment dispersions comprising the polymer of the present invention were prepared and tested as follows. Pigment wt % refers to the weight of pigment expressed as a percentage of the total weight of the dispersion.

In each case performance was compared to that achieved using a commercially available market leading polymer dispersant.

Example 2 - dispersion performance of pigment dispersions

Polymers of the invention (prepared as described in Example 1) were used to disperse a pigment in an organic medium to provide a pre-dispersed mixture. The pre-dispersed mixture was then ground on a triple roll mill, to provide a pigment dispersion having a particle size of <5 microns. To evaluate dispersion performance the flow characteristic of the pigment dispersion was determined visually (A: highly fluid liquid, B: fluid liquid, C: viscous liquid, D: thixotropic paste and E: paste). For some end applications it may be preferable to provide the pigment dispersion a highly fluid liquid. The results are shown in Table B.

Table B

Pigment Polymer Pigment Organic medium Flow dispersion

12 1 (4.5g) Pigment red Aldehyde resin (15g, Laropol A81) and C

57.1 (30g, 30 propylene glycol methyl ether acetate wt %) (50.5g)

13 5 (4.5g) Pigment red Aldehyde resin (15g, Laropol A81) and B

57.1 (30g, 30 propylene glycol methyl ether acetate (50.5 wt %) g)

15 7 (4.5g) Pigment red Aldehyde resin (15g, Laropol A81) and A

57.1 (30g, 30 propylene glycol methyl ether acetate wt %) (50.5g)

Competitive Pigment red C product 57.1 (30wt %)

17 7 (4.0g) Pigment red Aldehyde resin (15g, Laropol A81) and

57.1 (30g, 30 propylene glycol methyl ether acetate wt %) (50.5g)

18 1 (10g) Carbon black Aldehyde resin (15g, Laropol A81) and A

430 (20g, 20 propylene glycol methyl ether acetate (55g) wt %)

20 7 (10g) Carbon black Aldehyde resin (15g, Laropol A81) and A

430 (20g, 20 propylene glycol methyl ether acetate (55g) wt %)

21 10 (10 g) Carbon black Aldehyde resin (15g, Laropol A81) and A

430 (20g, 20 propylene glycol methyl ether acetate (55g) wt %)

Competitive Carbon black A product 430 (20 wt %)

22 9 (4 g) Pigment Aldehyde resin (15g, Laropol A81) and A yellow 74 propylene glycol methyl ether acetate (61 g) (20g, 20 wt %)

23 1 1 (4 g) Pigment Aldehyde resin (15g, Laropol A81) and A yellow 74 propylene glycol methyl ether acetate (61 g) (20g, 20 wt %) Competitive - Pigment - A product yellow 74 (20

wt %)

A: highly fluid liquid, B: fluid liquid, C: viscous liquid, D: thixotropic paste and E: paste.

The results in Table B show that the pigment dispersions comprising the polymer of the invention are comparable and in some cases superior to the competitive products in terms of flow performance.

Example 3 - gloss performance of diluted pigment dispersions

Pigment dispersions (50 g) (prepared as described in Example 2) were mixed with a dilution medium to provide a dilute pigment dispersion. To evaluate gloss performance the dilute pigment dispersion was applied as a film having a thickness of 90 microns to a test card (Hiding Power Chart 301 A, Sheen). The film was dried for 16 hours at 23°C and 50% humidity. The gloss of the cast film was then measured at 20 degrees using a glossmeter. The results are shown in Table C.

Table C

Dilute Pigment Pigment Dilution medium Gloss pigment dispersion (%) dispersion

B 17 Pigment red Aldehyde resin (30g, Laropol A81) and 79

57.1 (30g, 15 propylene glycol methyl ether acetate wt %) (20g)

C Competitive Pigment red 50 product 57.1 (15 wt %)

D 22 Pigment Aldehyde resin (30g, Laropol A81) and 63 yellow 74 propylene glycol methyl ether acetate (20g, 10 wt %) (20g)

E 23 Pigment Aldehyde resin (30g, Laropol A81) and 64 yellow 74 propylene glycol methyl ether acetate (20g, 10 wt %) (20g)

F Competitive Pigment 64 product yellow 74 (10

wt %) The results in Table C indicate that the dilute pigment dispersions comprising the polymer of the invention are comparable and in some cases superior to the competitive products in terms of gloss performance. Example 4 - dispersion performance of pigment dispersions

Polymers of the invention (prepared as described in Example 1) were used to disperse a pigment in dipropylene glycol diacrylate (DPGDA), to provide a pre-dispersion. The pre- dispersion was then ground on an Eiger ball mill, to provide a pigment dispersion having a particle size of <5 microns. To evaluate dispersion performance the flow characteristic of the pigment dispersion was determined visually (A: highly fluid liquid, B: fluid liquid, C: viscous liquid, D: thixotropic paste and E: paste). For some end applications it may be preferable to provide the pigment dispersion a highly fluid liquid. The results are shown in Table D. Table D

The results in Table D indicate that the pigment dispersions comprising the polymer of the invention are comparable and in some cases superior to the competitive products in terms of flow performance.

Example 5 - gloss performance of UV-curable pigment dispersions Pigment dispersion 26 was prepared according to the procedure of Example 4. For pigment dispersion 26, 6g of polymer 8 was used to disperse 30g of Pigment red 57.1 in 64g of DPGDA. The pigment dispersions were then mixed with trimethylolpropane ethoxylate triacrylate (TMP(EO)TA), epoxy acrylate in tripropylene glycol diacrylate (TPGDA) (4 epoxy acrylate : 1 TPGDA), and photo initiator blend (10g), to provide a UV-curable pigment dispersion. The UV- curable pigment dispersion was cast into a film having a thickness of 24 microns, and then cured using a GEW UV laboratory curing unit. The gloss of the cast film was determined at 20 degrees. The results are shown in Table E.

Table E

The results in Table E indicate that the UV-curable pigment dispersions comprising the polymer of the invention are comparable and in some cases superior to the competitive products in terms of gloss performance.

Claims

1 . A polymer of formula (I)

P-[-(A)_x-Z

(I)

wherein P is a polyalkyleneimine backbone;

A is a carbonylalkyleneoxy group;

each x is at least 1 ; and

y is a number less than or equal to the number of reactive amine groups in P.

2. A method of preparing a polymer of formula (I):

(I)

wherein P is a polyalkyleneimine backbone;

A is a carbonylalkyleneoxy group;

each x is at least 1 ; and

y is a number less than or equal to the number of reactive amine groups in P;

the method comprising the steps of:

(a) providing a polyalkyleneimine;

(b) reacting the polyalkyleneimine with an optionally substituted lactone; and

3. A composition comprising a polymer of formula (I):

(I)

wherein P is a polyalkyleneimine backbone;

A is a carbonylalkyleneoxy group;

each x is at least 1 ; and

y is a number less than or equal to the number of reactive amine groups in P;

and one or more further components.

4. Use of a polymer of formula (I):

(I)

wherein P is a polyalkyleneimine backbone;

A is a carbonylalkyleneoxy group;

each x is at least 1 ; and

y is a number less than or equal to the number of reactive amine groups in P;

as a dispersant.

(I)

wherein P is a polyalkyleneimine backbone;

A is a carbonylalkyleneoxy group;

each x is at least 1 ; and

y is a number less than or equal to the number of reactive amine groups in P;

to provide a synergistic effect when used in combination with a co-dispersant.

6. A polymer, method, composition or use according to any preceding claim, wherein P is represented stoichiometrically by the structure of formula (II):

(ll) wherein m is from 1 to 10000. 7. A polymer, method, composition or use according to any preceding claim, wherein P has a weight average molecular weight of from 5000 to 30000.

8. A polymer, method, composition or use according to any preceding claim, wherein each A is a carboxyalkyleneoxy group of formula CORO, wherein R is an optionally substituted alkylene group.

9. A polymer, method, composition or use according to any preceding claim, wherein A is a carbonylpentyleneoxy group or a carbonylpropyleneoxy group. 10. A polymer, method, composition or use according to any preceding claim, wherein at least 60% of groups Z are CR R²CR³R⁴OH.

1 1 . A polymer, method, composition or use according to any preceding claim, wherein R is hydrogen; R³ is hydrogen; R² is hydrogen or an optionally substituted hydrocarbyl group, preferably having 1 to 20, suitably 4 to 16 carbon atoms; and R⁴ is an optionally substituted hydrocarbyl group, preferably having 1 to 20, suitably 4 to 16 carbon atoms.

12. A polymer, method, composition or use according to claim 1 1 , wherein R² is hydrogen or an optionally substituted alkyl or alkenyl group, preferably having 1 to 20, suitably 4 to 16 carbon atoms; and R⁴ is selected from:

an ester containing group of formula R^aCOOR^b wherein R^a is an optionally substituted alkylene or alkenylene group, preferably having 1 to 16, preferably 2 to 12 carbon atoms and R^b is an optionally substituted alkyl or alkenyl group, preferably having from 1 to 16, preferably from 2 to 12 carbon atoms; and an ether containing group of formula -CH₂OR wherein R is an optionally substituted alkyl or alkenyl group, preferably having from 1 to 50, preferably from 8 to 20, more preferably from 10 to 15, most preferably from 12 to 14 carbon atoms. 13. The method according to claims 2 or 6 to 12, wherein step (b) and step (c) are each carried out in the presence of a catalyst.

14. The composition according to claim 3 or 6 to 12, wherein the composition further comprises a pigment.

15. The composition according to claim 3, 6 to 12, or 14, wherein the composition further comprises a diluent, carrier or co-dispersant.

16. The composition according to claim 3, 6 to 12, or 14 to 15 wherein the composition is an ink, paint, personal care, agrochemical, oilfield, lubricant or fuel composition.