ALKYL COPOLYMER THICKENER

Abstract

The invention relates to a thickening (meth)acrylic copolymer prepared using a polyalkoxylated Guerbet alcohol comprising a doubly branched alkyl group. The method for preparing this copolymer and its use in aqueous compositions, particularly coating compositions, are also part of the invention.

Description

Title of the invention: Thickening Alkyl Copolymer

[0001] The invention relates to a thickening (meth)acrylic copolymer prepared using a polyalkoxylated Guerbet alcohol comprising a doubly branched alkyl group. The method for preparing this copolymer and its use in aqueous compositions, particularly in coating compositions, also form part of the invention.

[0002] Many technical fields require the use of aqueous compositions. In particular, aqueous compositions of hydraulic binders, aqueous adhesives, aqueous detergents, aqueous cosmetics, aqueous inks, aqueous paper coatings, aqueous coatings, including aqueous varnishes, and aqueous paints, such as aqueous decorative paints or aqueous industrial paints, are known. In addition to their functional properties, these aqueous compositions must have a texture suitable for their use or storage. In particular, they must have a suitable viscosity. Furthermore, these aqueous compositions must be usable under conditions that can vary widely. In particular, the viscosity of these aqueous compositions can vary or degrade.The functional properties of these aqueous compositions can therefore be altered if their rheological behavior is not suitable, for example, to prevent sedimentation or phase separation during storage, which can also manifest as viscosity variations. Such variations or degradations are particularly detrimental or damaging to aqueous hydraulic binder compositions, aqueous adhesive compositions, aqueous detergent compositions, aqueous cosmetic compositions, aqueous ink compositions, aqueous paper coating compositions, aqueous coating compositions, and especially aqueous varnish or paint compositions.

[0003] There is therefore a need to be able to have aqueous compositions which do not present such disadvantages or aqueous compositions which do not lead to such problems.

[0004] In particular, it is especially useful to have aqueous coating compositions, particularly aqueous varnish or paint compositions, with a viscosity adapted to maintain their homogeneity and the integrity of their functional properties. Maintaining the viscosity and limiting the loss of viscosity of these aqueous compositions should be possible for wide ranges of shear gradient.

[0005] Consequently, many aqueous coating compositions utilize rheology-modifying polymers. These polymers should enable aqueous compositions to achieve the desired rheological properties over a wide range of shear rates. These polymers should also improve the shear-thinning of these aqueous compositions by providing sufficient pseudoplasticity, ensuring their stability and homogeneity during storage, facilitating their transfer onto application tools, and helping to limit the occurrence of runs after application. The compatibility of the various components of an aqueous coating composition must also be considered. In particular, it is important that the thickening copolymer and the pigments and binders used are compatible.

[0006] Furthermore, it is also important to improve the pigment compatibility of aqueous coating compositions, particularly paint compositions, especially with regard to the addition of pigment concentrates used for coloring. Without good pigment compatibility, the rheology of the composition can be severely degraded. Insufficient pigment compatibility can also lead to a decrease in color strength and result in an uneven or washed-out shade, potentially requiring the use of a larger quantity of pigment or causing aesthetic defects in the final coating.

[0007] Polymers known as thickening agents do not always provide a satisfactory solution to these various problems. Therefore, there is a need for improved rheology-modifying copolymers. The copolymer according to the invention provides a solution to all or part of the problems of prior art polymers.

[0008] Thus, the invention provides a copolymer P prepared by at least one polymerization reaction: * of at least one anionic monomer (a) selected from acrylic acid, a salt of acrylic acid, methacrylic acid, a salt of methacrylic acid and their combinations; * of at least one CrC8 ester (b) of a compound derived from an acid selected from acrylic acid, methacrylic acid, maleic acid, itaconic acid and crotonic acid; * of at least one compound (c) prepared by reaction: ** of at least one compound (d) obtained by: *** Dimerization of two identical or different compounds of formula I: [Chem I] R-CH[(CH2)mCH3]-(CH2)n-OH (I) in which: - R independently represents a linear C4-C9-alkyl group; - m represents independently 0 or 1; - n independently represents a number from 2 to 7; and ***polyalkoxylation of the resulting dimer, and ** of at least one compound (e) comprising a polymerizable function and another reactive function with the hydroxyl group of compound (d).

[0009] Preferably for the copolymer P according to the invention, the anionic monomer (a) is chosen from acrylic acid, methacrylic acid and their combinations.

[0010] Also preferably for the copolymer P according to the invention, the ester (b) is a Ci-C7 ester or a Ci-C6 ester or a Ci-C4 ester, preferably a CrC3 ester.

[0011] Also preferably for the copolymer P according to the invention, the ester (b) is an acrylic acid ester or a methacrylic acid ester, preferably an acrylic acid ester. In particular, the ester (b) is selected from methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, ethylhexyl methacrylate, and combinations thereof. More preferably, the ester (b) is selected from ethyl acrylate, methyl acrylate, butyl acrylate, methyl methacrylate, and combinations thereof.

[0012] Essentially, according to the invention, compound (d) is obtained by a dimerization reaction of two compounds of formula I. This dimerization is a Guerbet reaction carried out with these two alcohols of formula I. The dimerization reaction and its implementation conditions are known as such. Compound (d) can be prepared from a single compound of formula I or from two different compounds of formula I. The resulting dimer is treated to obtain the polyalkoxylated compound (d).

[0013] Preferably according to the invention, the dimerization of two identical compounds of formula I leads to a homodimer (dl). Also preferably according to the invention, compound (d) is a homodimer (dl) obtained by dimerization of two identical compounds of formula I in which: - R represents a linear C5-C7-alkyl group; - m represents 0 or 1, preferably 0; - n represents a number from 2 to 7.

[0014] More preferably according to the invention, compound (d) is a homodimer (dl) obtained by dimerization of two identical compounds of formula I in which: - R represents a linear C4-C9-alkyl group, preferably a C5- group C7-linear alkyl; - m represents 0 or 1, preferably 0; - n represents a number from 5 to 7, preferably from 4 to 6, more preferably 4 or 5.

[0015] In a particularly preferred manner according to the invention, dimerization is carried out starting from two different compounds (d) of formula I and leads to a mixture comprising two different homodimers (d1) and one heterodimer (d2). Preferably, this is a mixture consisting of two different homodimers (d1) and one heterodimer (d2). Also preferably, a mixture of compounds (d) can be obtained by dimerization of two different compounds of formula I in which: - R independently represents a linear C5-C7-alkyl group; - m represents independently 0 or 1, preferably 0; - n independently represents a number from 2 to 7.

[0016] Preferably according to the invention, a mixture of compounds (d) can be obtained by dimerization of two different compounds of formula I in which: - R independently represents a linear C4-C9-alkyl group, preferably a linear C5-C7-alkyl group; - m represents independently 0 or 1, preferably 0; - n independently represents a number from 5 to 7, preferably from 4 to 6, more preferably 4 or 5.

[0017] A preferred mixture of compounds (d) comprises a heterodimeric compound (d2) obtained by dimerization of a first compound of formula I in which R represents a linear C5-alkyl group, m represents 0 and n represents 5 and of a second different compound of formula I in which R represents a linear C7-alkyl group, m represents 0 and n represents 4.

[0018] A particularly preferred mixture of compounds (d) comprises: - a heterodimeric compound (d2) obtained by dimerization of a first compound of formula I in which R represents a linear C5-alkyl group, m represents 0 and n represents 5 and of a second different compound of formula I in which R represents a linear C7-alkyl group, m represents 0 and n represents 4, - a first homodimer (dl) obtained by dimerization of a compound of formula I in which R represents a linear C5-alkyl group, m represents 0 and n represents 5, - a second homodimer (dl) obtained by dimerization of a different compound of formula I in which R represents a linear C7-alkyl group, m represents 0 and n represents 4.

[0019] According to the invention, dimerization carried out from two different formula I compounds can lead to a mixture consisting of 2 different homodimers (dl) and a heterodimer (d2).

[0020] According to the invention, compound (d) is prepared by dimerization of two compounds of formula I and polyalkoxylation of the resulting dimer. The polyalkoxylation reaction and its implementation conditions are known as such. Preferably for the copolymer P according to the invention, compound (d) comprises from 10 to 150 alkoxylations. More preferably, compound (d) comprises from 20 to 100 alkoxylations or from 10 to 70 alkoxylations, and more preferably from 20 to 60 alkoxylations. Also preferably, compound (d) is polyethoxylated or is polyethoxylated-polypropoxylated or is polyethoxylated-polybutoxylated; preferably, compound (d) is polyethoxylated. More preferably, compound (d) is polyethoxylated. Particularly preferred, compound (d) comprises from 10 to 150 ethoxylations, more preferably from 20 to 100 ethoxylations or from 10 to 70 ethoxylations, much more preferably from 20 to 60 ethoxylations.

[0021] According to the invention, compound (e) comprises a polymerizable function, preferably a terminal ethylenic group, which is capable of reacting with the polymerizable groups of compounds (a) and (b). Preferably according to the invention, the polymerizable function of compound (e) is selected from vinyl, allyl, methallyl, isoprenyl, styrylyl, acrylate, methacrylate, itaconate, maleate, and crotonate.

[0022] Preferably according to the invention, compound (e) can be selected from acrylic acid, methacrylic acid, maleic acid, itaconic acid, crotonic acid, acrylic anhydride, methacrylic anhydride, maleic anhydride, itaconic anhydride, styrylyl-isocyanates (for example 3-isopropenyl-a,a'-dimethylbenzyl isocyanate or TMI, CAS number 2094-99-7), acrylate-alkylene-isocyanates (for example 2-isocyanatoethyl acrylate, CAS number 13641-96-8), methacrylate-alkylene-isocyanates (for example 2-isocyanatoethyl methacrylate, CAS number 30674-80-7) and their combinations.

[0023] Also preferably according to the invention, the compound (e) can be prepared by pre-reaction of a diisocyanate compound (for example tolyl-diisocyanate, isophorone-diisocyanate) and at least one compound selected from ethylene glycol acrylate, ethylene glycol methacrylate, isoprenol, vinyl-ethylene glycol, allyl alcohol, methallyl alcohol, hydroxybutyl-vinyl ether and their combinations.

[0024] More preferably according to the invention, the compound (e) is selected from acrylic anhydride, methacrylic anhydride, 3-isopropenyl-a, a'-dimethylbenzyl isocyanate, 2-isocyanatoethyl acrylate, 2-isocyanatoethyl methacrylate, a compound prepared by prior reaction of tolyl-diisocyanate or isophorone-diisocyanate and ethylene glycol methacrylate and their combinations.

[0025] For the preparation of copolymer P according to the invention, the quantities of compounds (a), (b) and (c) may vary. Preferably for copolymer P, the reaction of Polymerization involves: - from 20 to 74.9% by weight or from 25 to 69.5% by weight, preferably from 30 to 68% by weight or from 35 to 60% by weight, of monomer (a) or - from 25 to 79.9% by weight or from 30 to 74.5% by weight, preferably from 30 to 68% by weight or from 35 to 64.5% by weight, of monomer (b), or - from 0.1 to 55% by weight or from 0.5 to 45% by weight, preferably from 2 to 40% by weight or from 5 to 30% by weight, of monomer (c), compared to the total weight quantity of monomers (a), (b) and (c).

[0026] Also preferably according to the invention, the polymerization reaction can involve: - from 20 to 74.9% by weight of monomer (a), - from 25 to 79.9% by weight of monomer (b), and - from 0.1 to 55% by weight of monomer (c), compared to the total weight quantity of monomers (a), (b) and (c).

[0027] Also preferably according to the invention, the polymerization reaction can involve: - from 25 to 69.5% by weight of monomer (a), - from 30 to 74.5% by weight of monomer (b), and - from 0.5 to 45% by weight of monomer (c), compared to the total weight quantity of monomers (a), (b) and (c).

[0028] Also preferably according to the invention, the polymerization reaction can involve: - 30 to 68% by weight of monomer (a), - 30 to 68% by weight of monomer (b), and - from 2 to 40% by weight of monomer (c), compared to the total weight quantity of monomers (a), (b) and (c).

[0029] Also preferably according to the invention, the polymerization reaction can involve: - 35 to 60% by weight of monomer (a), - from 35 to 64.5% by weight of monomer (b), and - 5 to 30% by weight of monomer (c), compared to the total weight quantity of monomers (a), (b) and (c).

[0030] According to the invention, the polymerization reaction may involve only compounds (a), (b), and (c) or may involve one or more additional compounds. The polymerization reaction may also involve at least one crosslinking monomer (f) or at least one monomer (f) comprising at least two olefinic unsaturations, preferably less than 5% by weight, preferably from 0.01 to 4% by weight, in particular from 0.02 to 4% by weight or from 0.02 to 2% by weight. in particular 0.02 to 1% by weight of monomer (f) relative to the total weight quantity of monomers.

[0031] According to the invention, the polymerization reaction can also utilize at least one hydrophobic monomer (g) different from compound (c), preferably chosen from a compound of formula (II): [Chem II] R1-(OE)m-(OP)p-R2 (II) in which: - m and p, whether identical or different, independently represent 0 or an integer or decimal number less than 150, where m or p is different from 0. - OE independently represents a CH2CH2O group, - OP independently represents a group chosen from CH(CH3)CH2O and CH2 CH(CH3)O, - R1 independently represents a group comprising at least one polymerizable olefinic unsaturation, preferably an acrylate group or a methacrylate group and - R2 independently represents a Ce-C^-alkyl group, linear or branched, a phenyl group, a polyphenyl group, preferably a Ci0-C30-alkyl group, linear or branched, more preferably a Ci2-C22-alkyl group, linear or branched, or a group comprising 2 to 5 phenyls or a tristyrylphenyl group or a pentastyrylcumylphenyl group, preferably less than 20% by weight, preferably from 0.05 to 20% by weight, in particular from 0.1 to 10% by weight, of monomer (g) relative to the total weight of monomers.

[0032] More preferably, the polymerization reaction may involve at least one compound (h) selected from 2-acrylamido-2-methylpropane sulfonic acid, ethoxymethacrylate sulfonic acid, sodium methallyl sulfonate, styrene sulfonate, hydroxyethyl acrylate phosphate, hydroxypropyl acrylate phosphate, hydroxyethylhexyl acrylate phosphate, hydroxyethyl methacrylate phosphate, hydroxyethylhexyl methacrylate phosphate, their salts and combinations, preferably less than 20% by weight, preferably from 0.2 to 20% by weight, in particular from 0.5 to 10% by weight, of monomer (h) relative to the total weight amount of monomers.

[0033] Also preferably, the polymerization reaction may involve at least one compound (i) selected from hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethylhexyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, hydroxyethylhexyl methacrylate, preferably less than 20% by weight, preferably from 0.2 to 20% by weight, in particular from 0.5 to 10% by weight, of monomer (i) per ratio to the total weight quantity of monomers.

[0034] According to the invention, the copolymer P can be used as is, in an acidic form, or it can be totally or partially neutralized or coacervated. Preferably, the copolymer P can be totally or partially neutralized, preferably by means of at least one compound selected from NaOH, KOH, ammonium derivatives, ammonia, amino bases, for example triethanolamine, aminomethylpropanol or 2-amino-2-methylpropanol (AMP) and combinations thereof. Also preferably, the copolymer P can be totally or partially coacervated, preferably by reducing the pH, for example by reducing the pH to a value below 6.5, or by increasing the ionic strength.The reduction of pH can be achieved by means of an acidic compound, in particular by means of at least one organic or mineral acidic compound, including an acidic compound selected from phosphoric acid, citric acid, glucono-lactone, lactic acid, salicylic acid, glycolic acid, ascorbic acid, glutamic acid, hydrochloric acid, acetic acid, D-gluconic acid, sulfonic acid, methanesulfonic acid, benzimidazolesulfonic acid, tartaric acid, 4-aminobenzoic acid, benzoic acid, sorbic acid, phenylbenzimidazolesulfonic acid, benzylidene camphorsulfonic acid, terephthalylidene dicamphorsulfonic acid, kojic acid, hyaluronic acid.The increase in ionic strength can be achieved by adding at least one ionized compound or at least one salt, in particular NaCl, KCl, MgCl2, CaCl2, MgSO4, CaSO4, or by adding phenylbenzimidazole-sulfonic acid (PBSA) or sodium salt of pyroglutamic acid (NaPCA), or by adding at least one ionized organic sunscreen.

[0035] Generally, according to the invention, the copolymer P in solution in water has a pH greater than 4, preferably greater than 5, more preferably greater than 6 or 6.5. The copolymer P generally has a pH less than 13, preferably less than 12, more preferably less than 11. In particular, the copolymer P has a pH ranging from 4 to 13 or from 4 to 12 or from 4 to 11, preferably ranging from 5 to 13 or from 5 to 12 or from 5 to 11, more preferably ranging from 6 to 13 or from 6 to 12 or from 6 to 11, also more preferably ranging from 6.5 to 13 or from 6.5 to 12 or from 6.5 to 11.

[0036] The copolymer P according to the invention can be used in many technical fields, in particular as a rheology control agent. It can be incorporated into various compositions. Thus, the invention provides a rheology control composition comprising at least one copolymer P according to the invention and water.

[0037] The rheological control composition according to the invention is particularly suitable for facilitating the use of pigments in aqueous media, especially organic or mineral pigments. It can be incorporated into a specific pigment formulation. Thus, the invention provides an aqueous formulation including: - at least one rheological control composition according to the invention; optionally - at least one organic or mineral pigment or organic, organometallic or mineral particles, for example calcium carbonate, talc, kaolin, mica, silicates, silica, metal oxides, in particular titanium dioxide, iron oxides; and optionally - at least one agent selected from a particle spacer, a dispersing agent, a steric stabilizer, an electrostatic stabilizer, an opacifying agent, a coloring agent, a solvent, a coalescing agent, an antifoaming agent, a preservative, a biocidal agent, a spreading agent, a thickening agent, a film-forming copolymer and mixtures thereof.

[0038] Preferably, the formulation according to the invention is a coating formulation, in particular an ink formulation, a varnish formulation, an adhesive formulation, a paint formulation, for example decorative paint or industrial paint.

[0039] The copolymer P according to the invention can also be used in the field of printing, particularly textile printing. Thus, the invention provides a concentrated aqueous pigment paste comprising at least one copolymer P according to the invention and at least one organic or mineral colored pigment.

[0040] The invention also provides a method for controlling the viscosity of an aqueous composition that includes the addition of at least one copolymer P according to the invention to that composition. The viscosity control method according to the invention is implemented for an aqueous composition that is an aqueous formulation according to the invention.

[0041] The advantageous, particular or preferred characteristics of the copolymer P according to the invention define rheological control compositions, aqueous formulations, pigment pastes as well as viscosity control methods according to the invention which are also advantageous, particular or preferred.

[0042] The following examples illustrate the different aspects of the invention. Examples

[0043] Example 1: preparation of PL P2, P3 copolymers according to the invention

[0044] Preparation of the compound (cl) according to the invention

[0045] In a first step, the following are weighed into an Erlenmeyer flask: 17.8g of toluene dii-socyanate (TDI), 0.098g of alloocimene, 0.255g of titanium bis(acetylacetonate) diisopropoxide (“Tyzor” AA 105) and 39.1g of ethyl acrylate (monomer b).

[0046] Next, 13.3 g of ethylene glycol methacrylate (EGMA) and 7.1 g of ethyl acrylate (monomer b) are weighed into a dropping funnel. The contents of this funnel are poured into the Erlenmeyer flask over 20 minutes at a temperature below 35°C and Allow to react for 30 minutes. The compound (el) (MAEG-TDI) is obtained.

[0047] In a second step, 250 g of compound (d2a) (prepared by Guerbet reaction dimerization of a compound of formula I in which R represents a linear C5-alkyl group, m represents 0 and n represents 5 and of a compound of formula I in which R represents a linear C7-alkyl group, m represents 0 and n represents 4, ethoxylated 50 times - "Isofol" 2426S-50OE) is weighed into a 1000 ml reactor which is maintained in a molten state at 65°C. The compound (el) is then poured over this compound (d2a) for 20 minutes at 65°C and the heating is maintained for 1 hour and 30 minutes. Finally, the mixture is diluted with 57.98 g of monomer b (ethyl acrylate) and 167.98 g of deionized water to obtain a liquid at room temperature. Monomer (cl) is obtained from compounds (d2a) and (el) in ethyl acrylate (monomer b).

[0048] Preparation of compound (c2) according to the invention

[0049] In a glass reactor, 200.0 g of compound (d2a) (“Isofol” 2426S-50OE), 0.126 g of alloocimene, and 12.02 g of methacrylic anhydride (compound e) are introduced. The mixture is heated at 82°C ± 2°C for 2 hours and 30 minutes. At room temperature, the resulting monomer (c2) is then diluted with 133.38 g of monomer (a) (methacrylic acid) and 59.96 g of deionized water.

[0050] Preparation and characterization of the copolymer (PI) according to the invention

[0051] In a glass reactor, 269 g of deionized water and 2.37 g of sodium dodecyl sulfate are introduced.

[0052] In a first glass beaker, 120.6g of monomer (a) (methacrylic acid), 148.5g of monomer (b) (ethyl acrylate), 23.9g of compound (cl), 2.43g of sodium dodecyl sulfate and 258.7g of deionized water are weighed.

[0053] In a second glass beaker, 0.318g of ammonium persulfate is weighed and dissolved in 5.6g of deionized water.

[0054] In a third container, of the disposable syringe type, 10.42g of monomer (h) (sodium salt of 2-acrylamido-2-methylpropane sulfonic acid) is weighed at 50% by weight in water.

[0055] The contents of the reactor are heated to a temperature of 85°C ± 2°C. In 2 hours, the reactants from the 3 containers are introduced into the polymerization reactor at a temperature of 85°C ± 2°C.

[0056] 0.224 g of ammonium persulfate dissolved in 22.4 g of deionized water are then added for 1 hour while maintaining the temperature at 85°C ± 2°C. Heating is maintained for 1 hour before allowing the medium to cool to room temperature.

[0057] The copolymer (PI) is obtained with 30.4% by weight of dry extract, the composition of which is detailed in Table 1.

[0058] Preparation and characterization of the copolymer (P2) according to the invention

[0059] In a glass reactor, 269 g of deionized water and 2.37 g of sodium dodecyl sulfate are introduced.

[0060] In a first glass beaker, 120.6 g of monomer (a) (methacrylic acid), 148.5 g of monomer (b) (ethyl acrylate), 23.9 g of monomer (cl), 2.43 g of sodium dodecyl sulfate, 258.7 g of deionized water and 1.0 g of n-dodecyl mercaptan are weighed.

[0061] In a second glass beaker, 0.318 g of ammonium persulfate is weighed and dissolved in 5.6 g of deionized water.

[0062] In a third container, of the disposable syringe type, 10.42 g of monomer (h) (sodium salt of 2-acrylamido-2-methylpropane sulfonic acid) is weighed at 50% by weight in water.

[0063] The contents of the reactor are heated to a temperature of 85°C ± 2°C.

[0064] For 2 hours, the reagents from the 3 containers are introduced into the polymerization reactor at a temperature of 85°C ± 2°C.

[0065] 0.224 g of ammonium persulfate dissolved in 22.4 g of deionized water are then added for 1 hour while maintaining the temperature at 85°C ± 2°C. Heating is maintained for 1 hour before allowing the medium to cool to room temperature.

[0066] A copolymer (P2) is obtained with 30.0% by weight of dry extract, the composition of which is detailed in Table 1.

[0067] Preparation and characterization of the copolymer (P3) according to the invention

[0068] In a glass reactor, 269 g of deionized water and 2.37 g of sodium dodecyl sulfate are introduced.

[0069] In a first glass beaker, 120.6 g of monomer (a) (methacrylic acid), 148.5 g of monomer (b) (ethyl acrylate), 23.9 g of monomer (cl), 2.43 g of sodium dodecyl sulfate, 258.7 g of deionized water and 0.5 g of n-dodecyl mercaptan are weighed.

[0070] In a second glass beaker, 0.318 g of ammonium persulfate is weighed and dissolved in 5.6 g of deionized water.

[0071] In a third container, of the disposable syringe type, 10.42 g of monomer (h) (sodium salt of 2-acrylamido-2-methylpropane sulfonic acid) is weighed at 50% by weight in water.

[0072] The contents of the reactor are heated to a temperature of 85°C ± 2°C.

[0073] In 2 hours, the reagents from the 3 containers are introduced into the polymerization reactor at a temperature of 85°C ± 2°C.

[0074] 0.224 g of ammonium persulfate dissolved in 22.4 g of deionized water are then added for 1 hour while maintaining the temperature at 85°C ± 2°C. Heating is maintained for 1 hour before allowing the medium to cool to room temperature.

[0075] A copolymer (P3) is obtained with 30.2% by weight of dry extract, the composition of which is detailed in Table 1.

[0076] Preparation and characterization of the copolymer (P4) according to the invention

[0077] In a glass reactor, 260.7 g of deionized water and 2.49 g of sodium dodecyl sulfate are introduced.

[0078] In a first glass beaker, 110.18 g of monomer a (methacrylic acid), 162.11 g of monomer b (ethyl acrylate), 30.3 g of compound (c2), 2.49 g of sodium dodecyl sulfate and 325 g of deionized water are weighed.

[0079] In a second glass beaker, 0.329 g of ammonium persulfate is weighed and dissolved in 4 g of deionized water.

[0080] The contents of the reactor are heated to a temperature of 85°C ± 2°C.

[0081] In 2 hours, the reactants from the 2 containers are introduced into the polymerization reactor at a temperature of 85°C ± 2°C.

[0082] 0.256 g of ammonium persulfate dissolved in 59 g of deionized water are then added over 1 hour while maintaining the temperature at 85°C ± 2°C. Heating is maintained for 1 hour before allowing the medium to cool to room temperature.

[0083] A copolymer (P4) is obtained with 30.0% by weight of dry extract, the composition of which is detailed in Table 1.

[0084] [Table 1] Cupolymer ) PI P2 | F3 i P4 | compound a in bridges) 40.45 compound b (weight) j 49.7$ 40.45 1 40.45 | 36.42 j 49.79 49.79 | 53.58 | ÇMpOSêcfW N, 02 8.02 | xo ' | 10 | compound h (¾ by weight) IJ? 1.75 | L75 | 0 )

[0085] Examples 2: Preparation and characterization of aqueous paint formulations according to the invention

[0086] By mixing the various ingredients under stirring, a matte paint formulation according to the invention is prepared. The compounds and quantities (g) used are detailed in Table 2.

[0087] [Tab 2] Ingredients of the matte paint formulation Quantity (g) “Ecodis” P90 (dispersant “Coatex”) 1.5 “Tego” 825 (anti-foam “Tego”) 0.5 “Tiona” 568 (TiO2 “Tronox”) 35.05 “Omyacoat” 850 OG (CaCO3 “Omya”) 105.1 “Omyacarb” 2 AV (CaCO3 “Omya”) 160.15 Acronal S790 (Binder BASF) 65.05 Monopropylene glycol 5 Texanol (Coalescent Eastman) 5 NH4OH (28% in water) 0.7 Aqueous composition of PI copolymer according to the invention 3.65 Water 118.3 Total 500.00

[0088] Then, the paint formulation is colored by adding 5% by weight of a black pigment (“Colanyl” N500 black “Clariant”) to obtain formulation Fl according to the invention. Similarly, aqueous formulations F2 and F3 according to the invention are prepared by replacing the copolymer composition PI respectively with the copolymer compositions P2 and P3 according to the invention.

[0089] Then, for each formulation Fl, F2 and F3, measurements are taken at 25°C: * Brookfield viscosity at 10 rpm (pBlO, mPa.s); * Brookfield viscosity at 100 rpm (pBlOO, mPa.s); * Plane Cone viscosity or ICI viscosity measured at high velocity gradient (pi, mPa.s); * Stormer viscosity measured using the standard modulus, at medium velocity gradient (pS, Krebs Units or KU).

[0090] The results are measured immediately after the addition of the black pigment (T=0) and measured 24 hours after this addition (T=24H). They are presented in Table 3.

[0091] The pigment compatibility of formulations Fl, F2 and F3 is evaluated on a dry paint film. The initially white paint is colored by adding 5% of a black pigment-based colorant (“Colanyl” N500 black “Clariant”), a percentage calculated relative to the weight of the white paint formulation.

[0092] The rub-out test, known as the finger rub test, of colored paint applied at a wet thickness of 150 micrometers to a contrast card allows a small portion of the surface of the freshly applied colored paint film to be subjected to a shearing effect generated by a circular motion of the finger. This shearing effect can modify the stability and distribution of the colored pigment within the matrix of the colored paint film and, consequently, the intensity of the color at the point where the paint was rubbed.

[0093] Once the coloured paint film is dry, the colour difference between the initially sheared area of ​​the coloured paint film and the unsheared area of ​​coloured paint is measured using a spectrophotometer of the spectro-guide sphere gloss type marketed by the company "Byk".

[0094] The color difference is quantified by the AE value calculated from the measurement parameters corresponding to the known chromatic space L*a*b*. A low AE value means a reduced color difference between the sheared and unsheared areas, and therefore improved pigment compatibility.

[0095] The unsheared colored paint area is also measured according to one of the parameters of the L*a*b* color space. The L* parameter quantifies the intensity of the color. A low value for the L* parameter indicates reduced lightness and therefore a greater black intensity, corresponding to an improvement in the pigment compatibility of the evaluated paint formulation in which the copolymer according to the invention is implemented. The results are presented in Table 3.

[0096] [Table 3] Viscosity (3 Çbïo 'Formulation Fl F2 | 13 41 000 i 8 849 | 29090; 4 640 1 79g 3 740 a S .............t H 9 89 .....3..... 106 w .............3 110 .....'>•••• 70 .....t..... 85 i jiBMÔ | 32.2 3133 3

[0097] For formulations Fl, F2, and F3 according to the invention, the copolymers according to the invention allow for precise control of the various viscosity components, both after preparation and over time. The copolymers according to the invention provide good pigment compatibility for these paint formulations.

Claims

Demands

1. Copolymer P prepared by at least one polymerization reaction: * of at least one anionic monomer (a) selected from acrylic acid, an acrylic acid salt, methacrylic acid, a methacrylic acid salt and their combinations; * of at least one Ci-C8 ester (b) of a compound derived from an acid selected from acrylic acid, methacrylic acid, maleic acid, itaconic acid and crotonic acid; * of at least one compound (c) prepared by reaction: ** of at least one compound (d) obtained by: ***dimerization of two identical or different compounds of formula I by a Guerbet reaction: [Chem I] R-CH[(CH2)mCH3]-(CH2)n-OH (D in which: - R independently represents a linear C4-C9-alkyl group; - m independently represents 0 or 1; - n independently represents a number from 2 to 7;and *** polyalkoxylation of the dimer obtained, and ** of at least one compound (e) comprising a polymerizable function and another reactive function with the hydroxyl group of compound (d).;

2. Copolymer P according to claim 1 wherein the anionic monomer (a) is selected from acrylic acid, methacrylic acid and their combinations.

3. Copolymer P according to any one of claims 1 or 2 wherein: * the ester (b) is a C1-C7 ester or a C1-C6 ester or a C1-C4 ester, preferably a C1-C3 ester, * the ester (b) is an acrylic acid ester or a methacrylic acid ester, preferably an acrylic acid ester, * the ester (b) is selected from methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, ethylhexyl methacrylate and combinations thereof, more preferably * the ester (b) is selected from ethyl acrylate, methyl acrylate, Butyl acrylate, methyl methacrylate and their combinations.

4. Copolymer P according to any one of claims 1 to 3, wherein: * Dimerization of two identical compounds of formula I leads to a homodimer (dl); or * Compound (d) is a homodimer (dl) obtained by dimerization of two identical compounds of formula I in which: - R represents a linear C5-C7-alkyl group; - m represents 0 or 1, preferably 0; - n represents a number from 2 to 7; or * Compound (d) is a homodimer (dl) obtained by dimerization of two identical compounds of formula I in which: - R represents a linear C4-C9-alkyl group, preferably a linear C5-C7-alkyl group; - m represents 0 or 1, preferably 0; - n represents a number from 5 to 7, preferably from 4 to 6, more preferably 4 or 5.

5. Copolymer P according to any one of claims 1 to 4, wherein: * Dimerization of two different compounds (d) of formula I leads to a mixture comprising two different homodimers (dl) and one heterodimer (d2); or * a mixture of compounds (d) is obtained by dimerization of two different compounds of formula I in which: - R independently represents a linear C5-C7-alkyl group; - m represents independently 0 or 1, preferably 0; - n independently represents a number from 2 to 7; or * a mixture of compounds (d) is obtained by dimerization of two different compounds of formula I in which: - R independently represents a linear C4-C9-alkyl group, preferably a linear C5-C7-alkyl group; - m represents independently 0 or 1, preferably 0; - n independently represents a number from 5 to 7, preferably from 4 to 6, more preferably 4 or 5; or * a mixture of compounds (d) comprising a heterodimeric compound (d2) obtained by dimerization of a first compound of formula I in which R represents a linear C5-alkyl group, m represents 0 and n represents 5 and a second different compound of formula I in which R represents a linear C7-alkyl group, m represents 0 and n represents 4; or * a mixture of compounds (d) comprising: ** a heterodimeric compound (d2) obtained by dimerization of a first compound of formula I in which R represents a linear C5-alkyl group, m represents 0 and n represents 5 and of a second different compound of formula I in which R represents a linear C7-alkyl group, m represents 0 and n represents 4, ** a first homodimer (dl) obtained by dimerization of a compound of formula I in which R represents a linear C5-alkyl group, m represents 0 and n represents 5, ** a second homodimer (dl) obtained by dimerization of a different compound of formula I in which R represents a linear C7-alkyl group, m represents 0 and n represents 4.

6. Copolymer P according to any one of claims 1 to 5, wherein: * Compound (d) comprises from 10 to 150 alkoxylations, preferably from 20 to 100 alkoxylations, or from 10 to 70 alkoxylations, more preferably from 20 to 60 alkoxylations, or * compound (d) is polyethoxylated or is polyethoxylated-polypropoxylated or is polyethoxylated-polybutoxylated, preferably compound (d) is polyethoxylated, or * Compound (d) comprises from 10 to 150 ethoxylations, preferably from 20 to 100 ethoxylations or from 10 to 70 ethoxylations, more preferably from 20 to 60 ethoxylations.

7. Copolymer P according to any one of claims 1 to 6, wherein: * the polymerizable function of compound (e) is a terminal ethylenic group, preferably selected from vinyl, allyl, methallyl, isoprenyl, styrylyl, acrylate, methacrylate, itaconate, maleate, crotonate, or * Compound (e) is selected from acrylic acid, methacrylic acid, maleic acid, itaconic acid, crotonic acid, acrylic anhydride, methacrylic anhydride, maleic anhydride, itaconic anhydride, styrylyl isocyanates (e.g., 3-isopropenyl-α,α'-dimethylbenzyl isocyanate or TMI, CAS No. 2094-99-7), acrylate alkylene isocyanates (e.g., 2-isocyanatoethyl acrylate, CAS No. 13641-96-8), methacrylate alkylene isocyanates (e.g., 2-isocyanatoethyl methacrylate, CAS No. 30674-80-7) and combinations thereof, or * Compound (e) is prepared by prior reaction of a du-socyanate compound (e.g., tolyl diisocyanate, isophorone diisocyanate) and of at least one compound selected from ethylene glycol acrylate, ethylene glycol methacrylate, isoprenol, vinyl ethylene glycol, allyl alcohol, methallyl alcohol, hydroxybutyl vinyl ether and their combinations.

8. Copolymer P according to any one of claims 1 to 7 wherein the polymerization reaction involves: - 20 to 74.9% by weight or 25 to 69.5% by weight, preferably 30 to 68% by weight or 35 to 60% by weight, of monomer (a) or - 25 to 79.9% by weight or 30 to 74.5% by weight, preferably 30 to 68% by weight or 35 to 64.5% by weight, of monomer (b), or - 0.1 to 55% by weight or 0.5 to 45% by weight, preferably 2 to 40% by weight or 5 to 30% by weight, of monomer (c), relative to the total amount by weight of monomers (a), (b) and (c).

9. Copolymer P according to any one of claims 1 to 8 wherein the polymerization reaction also involves: * at least one crosslinking monomer (f) or at least one monomer (f) comprising at least two olefinic unsaturations, preferably less than 5 wt%, preferably from 0.01 to 4 wt%, in particular from 0.02 to 4 wt% or from 0.02 to 2 wt%, in particular from 0.02 to 1 wt%, of monomer (f) relative to the total weight of monomers, or * at least one hydrophobic monomer (g) different from compound (c), preferably selected from a compound of formula (II): [Chem II] R'-(OE)m-(OP)p-R2 (II) wherein: - m and p, identical or different, independently represent 0 or an integer or decimal less than 150, m or p is different from 0, - OE independently represents a CH2CH2O group, - OP independently represents a group chosen from CH(CH3)CH2O and CH2CH(CH3)O,- R1 independently represents a group comprising at least one polymerizable olefinic unsaturation, preferably an acrylate group or a methacrylate group and - R2 independently represents a linear or branched Ce-C-alkyl group, a phenyl group, a polyphenyl group, preferably a linear or branched Ci0-C30-alkyl group, more preferably, typically a linear or branched Ci2-C22-alkyl group, or a group comprising 2 to 5 phenyl groups, or a tristyrylphenyl group, or a pentastyrylcumylphenyl group, preferably less than 20% by weight, preferably from 0.05 to 20% by weight, in particular from 0.1 to 10% by weight, of monomer (g) relative to the total weight of monomers, or * at least one compound (h) selected from 2-acrylamido-2-methylpropane sulfonic acid, ethoxymethacrylate sulfonic acid, sodium methallyl sulfonate, styrene sulfonate, phosphated hydroxypropyl acrylate, phosphated hydroxyethylhexyl acrylate, phosphated hydroxyethyl methacrylate, phosphated hydroxypropyl methacrylate, hydroxyethylhexyl-methacrylate phosphate, their salts and combinations thereof, preferably less than 20% by weight, preferably from 0.2 to 20% by weight, in particular from 0.5 to 10% by weight, of monomer (h) relative to the total weight of monomers, or * at least one compound (i) selected from hydroxyethyl-acrylate, hydroxypropyl-acrylate, hydroxyethylhexyl-acrylate, hydroxyethyl-methacrylate, hydroxypropyl-methacrylate, hydroxyethylhexyl-methacrylate, preferably less than 20% by weight, preferably from 0.2 to 20% by weight, in particular from 0.5 to 10% by weight, of monomer (i) relative to the total amount by weight of monomers.

10. Copolymer P according to any one of claims 1 to 9: * totally or partially neutralized, preferably by means of at least one compound selected from NaOH, KOH, ammonium derivatives, ammonia, amino bases, for example triethanolamine, aminomethylpropanol or 2-amino-2-methylpropanol (AMP) and their combinations, or * fully or partially coacerbated, preferably: - by reducing the pH, for example by reducing the pH to a value below 6.5, in particular by means of an acidic compound, in particular by means of at least one organic or mineral acidic compound, in particular an acidic compound selected from phosphoric acid, citric acid, gluconolactone, lactic acid, salicylic acid, glycolic acid, ascorbic acid, glutamic acid, hydrochloric acid, acetic acid, D-gluconic acid, sulfonic acid, methanesulfonic acid, benzimidazolesulfonic acid, tartaric acid, 4-aminobenzoic acid, benzoic acid, sorbic acid, phenylbenzi- midazole sulfonic acid, benzylidene camphor sulfonic acid, te-rephthalylidene dicamphor sulfonic acid, kojic acid, hyaluronic acid or - by increasing the ionic strength, for example by adding at least one ionized compound or at least one salt, in particular NaCl, KCl, MgCl2, CaCl2, MgSO4, CaSO4, or by adding phenylbenzamide sulfonic acid (PBSA) or sodium salt of pyroglutamic acid (NaPCA) or by adding at least one ionized organic sunscreen.

11. Copolymer P according to any one of claims 1 to 10, in solution in water, * having a pH greater than 4, preferably greater than 5, more preferably greater than 6 or 6.5 or * having a pH less than 13, preferably less than 12, more preferably less than 11 or * having a pH from 4 to 13 or from 4 to 12 or from 4 to 11, preferably from 5 to 13 or from 5 to 12 or from 5 to 11, more preferably from 6 to 13 or from 6 to 12 or from 6 to 11, also more preferably from 6.5 to 13 or from 6.5 to 12 or from 6.5 to 11.

12. Rheological control composition comprising at least one copolymer P according to any one of claims 1 to 11 and water.

13. Aqueous formulation comprising: - at least one composition according to claim 12; optionally - at least one organic or mineral pigment or organic, organometallic or mineral particles, for example calcium carbonate, talc, kaolin, mica, silicates, silica, metal oxides, in particular titanium dioxide, iron oxides; and optionally - at least one agent selected from a particle spacer, a dispersing agent, a steric stabilizing agent, an electrostatic stabilizing agent, an opacifying agent, a coloring agent, a solvent, a coalescing agent, an antifoaming agent, a preservative, a biocidal agent, a spreading agent, a thickening agent, a film-forming copolymer and mixtures thereof.

14. Formulation according to claim 13 of coating, in particular an ink formulation, a varnish formulation, an adhesive formulation, a paint formulation, for example decorative paint or industrial paint.

15. Concentrated aqueous pigment paste comprising at least one co- polymer P according to any one of claims 1 to 11 and at least one organic or mineral colour pigment.

16. Method for controlling the viscosity of an aqueous composition comprising the addition of at least one copolymer P according to any one of claims 1 to 11 in this composition.

17. Method according to claim 16 wherein the aqueous composition is an aqueous formulation defined according to one of claims 13 or 14.