THICKENING ALKYLATED URETHANE COPOLYMER

Abstract

The invention relates to a thickening urethane copolymer prepared using a non-alkoxylated Guerbet alcohol comprising a doubly branched alkyl group. The method of preparing this copolymer and its use in aqueous compositions, in particular in coating compositions, are also part of the invention.

Description

Title of the invention: THICKENING ALKYLATED URETHANE COPOLYMER

[0001] The invention relates to a thickening urethane copolymer prepared using a non-alkoxylated Guerbet alcohol comprising a doubly branched alkyl group. The method of preparing this copolymer and its use in aqueous compositions, in particular in coating compositions, are also part of the invention.

[0002] Many technical fields require the use of aqueous compositions. In particular, aqueous hydraulic binder compositions, aqueous adhesive compositions, aqueous detergent compositions, aqueous cosmetic compositions, aqueous ink compositions, aqueous paper coating compositions, aqueous coating compositions, in particular aqueous varnish compositions or aqueous paint compositions, for example aqueous decorative paint compositions or aqueous industrial paint compositions, 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. In addition, these aqueous compositions must be able to be used under conditions which can vary widely. In particular, the viscosity of these aqueous compositions may vary or degrade.The functional properties of these aqueous compositions may therefore be altered if their rheological behavior is not suitable, for example to prevent sedimentation or phase separation phenomena during storage time, which may also manifest themselves by viscosity variations. Such variations or degradations are particularly detrimental or damaging for aqueous hydraulic binder compositions, for aqueous adhesive compositions, for aqueous detergent compositions, for aqueous cosmetic compositions, for aqueous ink compositions, for aqueous paper coating compositions, for aqueous coating compositions, in particular for aqueous varnish or paint compositions.

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

[0004] In particular, it is particularly useful to be able to have available aqueous coating compositions, in particular aqueous varnish or paint compositions, the viscosity of which is adapted to allow their homogeneity to be maintained. as well as the integrity of their functional properties. Maintaining viscosity and limiting viscosity loss of these aqueous compositions should be possible for wide shear rate ranges.

[0005] Therefore, many aqueous coating compositions use rheology-modifying polymers. These polymers should make it possible to give the aqueous compositions the desired rheological properties for wide shear rate ranges. These polymers should also improve the rheo-fluidification of these aqueous compositions by giving them sufficient pseudoplasticity, ensuring their stability and homogeneity during their storage life, facilitating their transfer to the application tools and helping to limit the appearance of drips once applied. The compatibility of the different constituents of an aqueous coating composition must also be taken into account. In particular, it is important that the thickening copolymer and the pigments and binders used have good compatibility.

[0006] Furthermore, it is also important to improve the pigment compatibility of aqueous coating compositions, in particular paint compositions, and particularly with regard to the addition of pigment concentrates used for coloring. In the absence of good pigment compatibility, the rheology of the composition can be significantly degraded. Insufficient pigment compatibility can also lead to a reduction in coloring strength and result in an uneven or washed-out shade, which may result in the use of a higher quantity of pigment or the presence of aesthetic defects in the final coating.

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

[0008] Thus, the invention provides a copolymer P prepared by at least one polymerization reaction: • at least one isocyanate compound (a) independently chosen from a diisocyanate compound (a1), a polyisocyanate compound (a2) and combinations thereof; • at least one polyhydroxylated compound (b); • at least one compound (c) obtained by dimerization of two compounds identical or different of formula I: [°009] R-CH[(CH2)XH3]^^^ (I) in which:

[0010] - R independently represents a linear C4-C9-alkyl group;

[0011] - m independently represents 0 or 1;

[0012] - n independently represents a number ranging from 2 to 7.

[0013] Preferably for the copolymer P according to the invention, the isocyanate compound (a) is a diisocyanate compound (a1) chosen from:

[0014] - symmetrical aromatic diisocyanate compounds, preferably: • 2,2'-diphenylmethylene diisocyanate (2,2'-MDI) and 4,4'-diphenylmethylene diisocyanate (4,4'-MDI); • 4,4'-dibenzyl diisocyanate (4,4'-DBDI); • Toluene 2,6-diisocyanate (2,6-TDI); • m-xylylene diisocyanate (m-XDI);

[0015] - symmetrical alicyclic diisocyanate compounds, preferably methylene bis(4-cyclohexylisocyanate) (Hi2MDI);

[0016] - symmetrical aliphatic diisocyanate compounds, preferably diisocyanate hexamethylene (HDI), pentamethylene diisocyanate (PDI);

[0017] - asymmetric aromatic diisocyanate compounds, preferably: • 2,4'-diphenylmethylene diisocyanate (2,4'-MDI); • 2,4'-dibenzyl diisocyanate (2,4'-DBDI); • Toluene 2,4-diisocyanate (2,4-TDI);

[0018] - asymmetric alicyclic diisocyanate compounds, preferably diisocyanate of isophorone (IPDI).

[0019] Preferably according to the invention, the compound (al) is chosen from IPDI, HDI, Hi2MDI and their combinations.

[0020] Also preferably for the copolymer P according to the invention, the isocyanate compound (a) may be a polyisocyanate compound (a2) strictly comprising more than 2 isocyanate functions or more than 2.2 isocyanate functions or even more than 2.5 isocyanate functions. More preferably, the polyisocyanate compound (a2) comprises more than 2.6 isocyanate functions or more than 2.7 isocyanate functions or more than 3 isocyanate functions. Also more preferably, the polyisocyanate compound (a2) comprises from 2.2 to 6 isocyanate functions, from 2.2 to 4 isocyanate functions, from 2.2 to 3.5 isocyanate functions, from 2.5 to 6 isocyanate functions, from 2.2 to 5 isocyanate functions, from 2.5 to 4 isocyanate functions, from 2.5 to 3.5 isocyanate functions, in particular from 2.6 to 3.3 isocyanate functions.

[0021] Also preferably, the polyisocyanate compound (a2) is chosen from: • triphenylmethane-4,4',4”-triisocyanate or 1,1',1”-methylidynetris (4-isocyanatobenzene); • an isocyanurate compound, in particular an isocyanurate compound of a compound chosen from: - symmetrical aromatic diisocyanate compounds, preferably: • 2,2'-diphenylmethylene diisocyanate (2,2'-MDI) and 4,4'-diphenylmethylene diisocyanate (4,4'-MDI); • 4,4'-dibenzyl diisocyanate (4,4'-DBDI); • Toluene 2,6-diisocyanate (2,6-TDI); • m-xylylene diisocyanate (m-XDI); - symmetrical alicyclic diisocyanate compounds, preferably methylene bis(4-cyclohexylisocyanate) (Hi2MDI); - symmetrical aliphatic diisocyanate compounds, preferably hexamethylene diisocyanate (HDI), pentamethylene diisocyanate (PDI); - asymmetric aromatic diisocyanate compounds, preferably: • 2,4'-diphenylmethylene diisocyanate (2,4'-MDI); • 2,4'-dibenzyl diisocyanate (2,4'-DBDI); • Toluene 2,4-diisocyanate (2,4-TDI); • a trimeric biurea compound, in particular a trimeric biurea compound of a compound chosen from: - symmetrical aromatic diisocyanate compounds, preferably: • 2,2'-diphenylmethylene diisocyanate (2,2'-MDI) and 4,4'-diphenylmethylene diisocyanate (4,4'-MDI); • 4,4'-dibenzyl diisocyanate (4,4'-DBDI); • Toluene 2,6-diisocyanate (2,6-TDI); • m-xylylene diisocyanate (m-XDI); - symmetrical alicyclic diisocyanate compounds, preferably methylene bis(4-cyclohexylisocyanate) (Hi2MDI); - symmetrical aliphatic diisocyanate compounds, preferably hexamethylene diisocyanate (HDI), pentamethylene diisocyanate (PDI); - asymmetric aromatic diisocyanate compounds, preferably: • 2,4'-diphenylmethylene diisocyanate (2,4'-MDI); • 2,4'-dibenzyl diisocyanate (2,4'-DBDI); • Toluene 2,4-diisocyanate (2,4-TDI); - asymmetric alicyclic diisocyanate compounds, preferably isophorone diisocyanate (IPDI), preferably compound (a2) is selected from triphenylmethane-4,4',4”-triisocyanate, 1,1',1”-methylidynetris (4-isocyanatobenzene), HDI isocyanurate, IPDI isocyanurate, PDI isocyanurate, HDI biurea trimer and IPDI biurea trimer, PDI biurea trimer.

[0022] Preferably for the copolymer P according to the invention, the poly- compound hydroxylated (b) is a compound (bl) of formula II: [Chem II] HO-LP-OH (II) in which: - L independently represents an oxyalkylene residue;

[0023] - p independently represents a number ranging from 30 to 1000.

[0024] Preferably for the copolymer P according to the invention, the polyhydroxylated compound (b) is a compound (bl) of formula II in which: - L independently represents an oxyethylene residue; or

[0025] - p independently represents a number ranging from 50 to 400, preferably from 100 to 300.

[0026] More preferably for the copolymer P according to the invention, the polyhydroxylated compound (b) is a compound (b1) of formula II in which L independently represents an oxyethylene residue and p independently represents a number ranging from 50 to 400, preferably from 100 to 300.

[0027] According to the invention, the compound (b1) of formula II can be combined with a non-alkoxylated compound (b2) comprising at least three hydroxyl groups. Preferably according to the invention, the compound (b2) comprises three hydroxyl groups. Much more preferably, it is chosen from glycerol, pentaerythritol and their combinations.

[0028] According to the invention, the polyhydroxylated compound (b) may also be a polyalkoxylated compound (b3) comprising at least three hydroxyl groups. Preferably according to the invention, the compound (b3) is different from the compound (b2) and comprises three hydroxyl groups. Much more preferably, it is chosen from polyethoxylated glycerol, polyethoxylated pentaerythritol and combinations thereof.

[0029] Advantageously according to the invention, the copolymer P can be prepared using one or more combinations of the compounds (b1), (b2) and (b3).

[0030] Preferably according to the invention, compounds (b), (bl) or (b3) independently have a molar mass (Mw) measured by CES ranging from 1,500 to 40,000 g / mol, preferably from 2,000 to 20,000 g / mol, more preferably from 2,000 to 15,000 g / mol or from 2,000 to 12,000 g / mol. According to the invention, the molar mass of compounds (b), (bl) or (b3) is

[0031] determined by Size Exclusion Chromatography (SEC) or in English “Gel Permeation Chromatography” (GPC). This technique uses a Waters brand liquid chromatography device equipped with a detector. This detector is a Waters 2414 type refractometric concentration detector. This liquid chromatography device is equipped with two size exclusion columns in order to separate the different molecular weights of the polymers or compounds studied. The liquid elution phase is an organic phase composed of THF (HPLC grade, unstabilized). In a first step, approximately 25 mg of compound is solubilized in 5 mL of THF, to which 0.1 mol% of water is added, used as an internal flow marker. Then, the solution is filtered at 0.2 pm. 50 pL is then injected into the chromatography apparatus (eluent: THF, HPLC grade, unstabilized). The liquid chromatography apparatus contains an isocratic pump (Waters 515) whose flow rate is set at 0.3 mL / min. The chromatography apparatus also includes an oven that includes a column system in series: an Agilent PLgel MiniMIX-A column of 250 mm length and 4.6 mm diameter followed by an Agilent PLgel MiniMIX-B column of 250 mm length and 4.6 mm diameter. The detection system consists of a Waters RI 2414 refractometric detector.The columns are maintained at a temperature of 35°C and the refractometer is brought to a temperature of 35°C. The chromatography apparatus is calibrated using polymethyl methacrylate standards certified by the supplier Agilent (EasiVial PMMA).

[0032] Essentially according to the invention, compound (c) 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 conditions of implementation are known as such. Compound (c) can be prepared from the same compound of formula I or from two different compounds of formula I.

[0033] Preferably according to the invention, the dimerization of two identical compounds of formula I leads to a homodimer (c1). Also preferably according to the invention, compound (c) is a homodimer (c1) obtained by dimerization of two identical compounds of formula I in which:

[0034] - R represents a linear C5-C7-alkyl group;

[0035] - m represents 0 or 1, preferably 0;

[0036] - n represents a number ranging from 2 to 7.

[0037] More preferably according to the invention, compound (c) is a homodimer (cl) obtained by dimerization of two identical compounds of formula I in which

[0038] - R represents a linear C4-C9-alkyl group, preferably a C5 group - C7-linear alkyl;

[0039] - m represents 0 or 1, preferably 0;

[0040] - n represents a number ranging from 5 to 7, preferably from 4 to 6, more preferably usually 4 or 5.

[0041] In a particularly preferred manner according to the invention, the dimerization is carried out from two different compounds of formula I and results in a mixture comprising 2 different homodimers (c1) and one heterodimer (c2). Preferably, this is of a mixture consisting of 2 different homodimers (c1) and one heterodimer (c2). Also preferably, a mixture of compounds (c) can be obtained by dimerization of two different compounds of formula I in which:

[0042] - R independently represents a linear C5-C7-alkyl group;

[0043] - m independently represents 0 or 1, preferably 0;

[0044] - n independently represents a number ranging from 2 to 7.

[0045] Preferably according to the invention, a mixture of compounds (c) can be obtained by dimerization of two different compounds of formula I in which

[0046] - R independently represents a linear C4-C9-alkyl group, preferably a linear C5-C7-alkyl group;

[0047] - m independently represents 0 or 1, preferably 0;

[0048] - n independently represents a number ranging from 5 to 7, preferably from 4 to 6, more preferably 4 or 5.

[0049] A preferred mixture of compounds (c) comprises a heterodimeric compound (c2) 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.

[0050] A particularly preferred mixture of compounds (c) comprises:

[0051] - a heterodimeric compound (c2) 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,

[0052] - a first homodimer (cl) 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,

[0053] - a second homodimer (cl) obtained by dimerization of a compound different from formula I in which R represents a linear C7-alkyl group, m represents 0 and n represents 4.

[0054] According to the invention, the dimerization carried out from two different compounds of formula I can lead to a mixture consisting of 2 different homodimers (c1) and one heterodimer (c2).

[0055] For the preparation of the copolymer P according to the invention, the quantities of the compounds (a), (b) and (c) can vary. Preferably for the copolymer P, the polymerization reaction involves: - from 10 to 79.9 mol% or from 10 to 74.5 mol%, preferably from 10 to 68 mol% or from 10 to 60 mol%, of monomer (a) or - from 20 to 89.9 mol% or from 25 to 89.5 mol%, preferably from 30 to 88% molar or 35 to 85 mol% of monomer (b), or - from 0.1 to 70 mol% or from 0.5 to 65 mol%, preferably from 2 to 60 mol% or from 5 to 55 mol%, of monomer (c), relative to the total molar quantity of monomers (a), (b) and (c).

[0056] Also preferably according to the invention, the polymerization reaction can implement: - from 10 to 79.9 mol% or from 10 to 74.5 mol%, preferably from 10 to 68 mol% or from 10 to 60 mol%, of monomer (a), - from 20 to 89.9 mol% or from 25 to 89.5 mol%, preferably from 30 to 88 mol% or from 35 to 85 mol%, of monomer (b), and - from 0.1 to 70 mol% or from 0.5 to 65 mol%, preferably from 2 to 60 mol% or from 5 to 55 mol%, of monomer (c), relative to the total molar quantity of monomers (a), (b) and (c).

[0057] According to the invention, the polymerization reaction can use only compounds (a), (b) and (c) or use one or more other additional compounds. Then, the polymerization reaction can also use at least one hydrophobic compound (d) different from compound (c), preferably chosen from a compound of formula (III): [Chem III] R1-(OE)q-(OP)r-OH (III) in which: - q and r, identical or different, independently represent 0 or an integer or decimal number less than 150, q or r 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 linear or branched C6-C40-alkyl group, a phenyl group, a polyphenyl group, preferably a linear or branched C10-C30-alkyl group, more preferably a linear or branched C12-C22-alkyl group, or a group comprising 2 to 5 phenyls or a tristyrylphenyl group or a pentastyrylcumylphenyl group, preferably less than 20 mol %, preferably from 0.05 to 20 mol %, in particular from 0.1 to 10 mol %, of compound (d) relative to the total molar quantity of compounds involved.

[0058] 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 different compositions. Thus, the invention provides a rheological control composition comprising at least one copolymer P according to the invention. The composition rheological control according to the invention can be treated in an acidic manner leading to a pH lower than 8, preferably to a pH higher than 6. This treatment can be carried out using an acid, in particular a carboxylic acid such as acetic acid or lactic acid.

[0059] The rheological control composition according to the invention may also comprise at least one solvent, in particular water or a coalescence solvent, for example glycol, butyl glycol, butyl diglycol, monopropylene glycol, ethylene glycol, ethylene diglycol, Dowanol products whose CAS number is 34590-94-8), Texanol products whose CAS number is 25265-77-4); or combined with at least one additive chosen from an amphiphilic compound, in particular a surfactant compound, preferably a hydroxylated surfactant compound, for example alkyl-polyalkylene glycol, in particular alkyl-polyethylene glycol and alkyl-polypropylene glycol; a polysaccharide derivative, for example cyclodextrin, cyclodextrin derivative, polyethers, alkyl-glucosides; a hydrotropic compound, an anti-foaming agent, a biocidal agent and combinations thereof.

[0060] The rheological control composition according to the invention is particularly suitable for facilitating the use of pigments in an aqueous medium, in particular organic or mineral pigments. It can be incorporated into a particular pigmented formulation. Thus, the invention provides an aqueous formulation comprising: - 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 spacing agent, 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.

[0061] 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.

[0062] The copolymer P according to the invention can also be used in the field of printing, in particular 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.

[0063] The invention also provides a method for controlling the viscosity of an aqueous composition which comprises the addition of at least one copolymer P according to the invention to this composition. The method for controlling the viscosity according to the invention is implemented for an aqueous composition which is an aqueous formulation according to the invention.

[0064] 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.

[0065] The following examples illustrate the different aspects of the invention.

[0066] Examples:

[0067] Example 1: Preparation and characterization of the copolymer (PI) according to the invention

[0068] In a 3 L glass reactor equipped with mechanical stirring, a vacuum pump, a nitrogen inlet and heated by means of a double jacket in which oil circulates, a compound (b) (polyethylene glycol - molecular mass 10,000 g / mol) (148.6 g) is introduced which is heated to 95°C under vacuum. Under stirring and inert atmosphere, 200 ppm of a bismuth carboxylate type catalyst (K Kat B221) is added to the medium and then a compound (c) (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, non-ethoxylated - Isofol2426S) (16.4 g) is added over 5 min.Then, a dii-isocyanate compound (al) (isophorone diisocyanate, IPDI) (9.9 g) is introduced by means of a syringe under stirring at 150 rpm. The reaction is continued at 100°C for 1 hour.

[0069] Then, it is checked that the isocyanate level is zero by a back titration. 1 g of the reaction medium is taken to which an excess of dibutylamine (1 molar for example) is added, which reacts with the isocyanate functions potentially present in the medium. Any unreacted dibutylamine is then titrated with hydrochloric acid (1 N for example). The quantity of isocyanate functions present in the reaction medium can then be deduced. If this is not zero, the reaction is extended by periods of 15 minutes until the reaction is complete. When the level reaches zero, the copolymer PI is obtained, comprising 14 mol% of compound a, 43 mol% of compound b and 43 mol% of compound c. It is formulated using an ethoxylated alcohol surfactant compound (Emulan HE 51 Basf) (95 g), 1000 ppm of a biocidal agent (Biopol SMV Chemipol), 1000 ppm of an anti-foam agent (Tego 1488 Evonik) and water (730 g).We obtain an aqueous composition. consisting of 17.5% by mass of PI copolymer according to the invention, 9.5% by mass of surfactant compound and 73% by mass of water.

[0070] Examples 2: preparation and characterization of an aqueous paint formulation according to the invention

[0071] By mixing the different ingredients under agitation, a matt paint formulation according to the invention is prepared. The compounds and quantities (g) used are detailed in Table 1.

[0072] [Tab 1] Matt Paint Formulation Ingredients Quantity (g) Ecodis P50 (Coatex dispersant) 2.00 Tego 810 (Tego antifoam) 0.51 Acticide MBS (Thor batericide) 1.00 Tiona 568 (Tronox TiO2) 40.01 Omyacoat 850 OG (Omya CaCO3) 110.00 Durcal 2 AV (Omya CaCO3) 150.29 Acronal S790 (Basf binder) 65.00 Monopropylene glycol 5.06 Texanol (Eastman coalescent) 5.02 NaOH (20% in water) 0.41 Aqueous PI copolymer composition according to the invention 6.29 Water 114.41 Total 500.00

[0073] Then, the paint formulation is colored by adding 5% by weight of a black pigment (Colanyl N500 Clariant black) to obtain the formulation F1 according to the invention.

[0074] Then, for formulation F1, we measure, at 25°C: • Brookfield viscosity at 10 rpm (pBlO, rnPa.s); • Brookfield viscosity at 100 rpm (pBlOO, rnPa.s); • Cone-Plane viscosity or ICI viscosity measured at high velocity gradient (pi, rnPa.s); • Stormer viscosity measured using the standard module, at medium velocity gradient (pS, Krebs Units or KU).

[0075] 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 2.

[0076] The pigment compatibility of the Fl formulation is evaluated on a dry film of paint. The coloring of the initially white paint is obtained by adding 5% of black pigment-based colorant (Colanyl N500 Clariant black), a percentage calculated relative to the weight of the white paint formulation.

[0077] The test, known as such, of rubbing out the colored paint applied with a finger at a wet thickness of 150 micrometers on a contrast card (rub out test) makes it possible to subject a small part of the surface of the freshly applied colored paint film to a shearing effect generated by a circular movement of the finger. The shearing effect can modify the stability and distribution of the colored pigment in the matrix that constitutes the colored paint film and consequently, the intensity of the coloring at the location of the sheared zone.

[0078] Once the colored paint film is dry, the difference in coloring between the initially sheared area of ​​the colored paint film and the unsheared area of ​​colored paint is measured using a spectro-guide sphere gloss type spectrophotometer marketed by the company Byk.

[0079] The color difference is quantified by the AE value calculated from the measurement parameters corresponding to the known color space L*a*b*. A low AE value means a reduced color difference between the sheared area and the non-sheared area, and therefore an improvement in pigment compatibility.

[0080] The unsheared colored paint area is also subject to a measurement corresponding to one of the parameters of the L*a*b* color space. The L* parameter quantifies the intensity of the coloring. A low value for the L* parameter means reduced lightness and therefore a greater black intensity corresponding to an improvement in the pigment compatibility of the paint formulation evaluated in which the copolymer according to the invention is implemented. The results are presented in Table 2. Viscosity (mPa.s) Formulation Fl pBlO T=0 24,900 pBlOO 3,035 pS 107 pi 60 pBlO T=24H 24,050 pBlOO 3,155 pS 109 pi 60 pigment compatibility AE 3.15 L* 34.07

[0081] For the formulation F1 according to the invention, the copolymer according to the invention makes it possible to control the different components of the viscosity well, both after preparation and over time. The copolymer according to the invention provides good pigment compatibility to this paint formulation.

Claims

Claims

1. Copolymer P prepared by at least one polymerization reaction: • of at least one isocyanate compound (a) independently chosen from a diisocyanate compound (a1), a polyisocyanate compound (a2) and their combinations; • of at least one polyhydroxylated compound (b); • of at least one compound (c) obtained by dimerization by a Guerbet reaction of two identical or different compounds of formula I: (I) in which: - R independently represents a linear C4-C9-alkyl group; - m independently represents 0 or 1; - n independently represents a number ranging from 2 to 7.

2. Copolymer P according to claim 1 for which the isocyanate compound (a) is: • a diisocyanate compound (a1) chosen from: - symmetrical aromatic diisocyanate compounds, preferably: • 2,2'-diphenylmethylene diisocyanate (2,2'-MDI) and 4,4'-diphenylmethylene diisocyanate (4,4'-MDI); • 4,4'-dibenzyl diisocyanate (4,4'-DBDI); • 2,6-toluene diisocyanate (2,6-TDI); • m-xylylene diisocyanate (m-XDI); - symmetrical alicyclic diisocyanate compounds, preferably methylene bis(4-cyclohexylisocyanate) (Hi2MDI); - symmetrical aliphatic diisocyanate compounds, preferably hexamethylene diisocyanate (HDI), pentamethylene diisocyanate (PDI); - unsymmetrical aromatic diisocyanate compounds, preferably: • 2,4'-diphenylmethylene diisocyanate (2,4'-MDI); • 2,4'-dibenzyl diisocyanate (2,4'-DBDI); • Toluene 2,4-diisocyanate (2,4-TDI); - asymmetric alicyclic diisocyanate compounds, preferably isophorone diisocyanate (IPDI), preferably, the compound (al) is chosen from IPDI, HDI, Hn MDI and their combinations; or • - a polyisocyanate compound (a2) comprising strictly more of 2 isocyanate functions or more than 2.2 isocyanate functions or even more than 2.5 isocyanate functions; preferably, the polyisocyanate compound (a2) comprises more than 2.6 isocyanate functions or more than 2.7 isocyanate functions or more than 3 isocyanate functions; more preferably, the polyisocyanate compound (a2) comprises from 2.2 to 6 isocyanate functions, from 2.2 to 4 isocyanate functions, from 2.2 to 3.5 isocyanate functions, from 2.5 to 6 isocyanate functions, from 2.2 to 5 isocyanate functions, from 2.5 to 4 isocyanate functions, from 2.5 to 3.5 isocyanate functions, in particular from 2.6 to 3.3 isocyanate functions; or a polyisocyanate compound (a2) chosen from: • triphenylmethane-4,4',4”-triisocyanate or l,l',l”-methylidynetris (4-isocyanatobenzene); an isocyanurate compound, in particular an isocyanurate compound of a compound chosen from: - symmetrical aromatic diisocyanate compounds, preferably: • 2,2'-diphenylmethylene diisocyanate (2,2'-MDI) and 4,4'-diphenylmethylene diisocyanate (4,4'-MDI); • 4,4'-dibenzyl diisocyanate (4,4'-DBDI); • Toluene 2,6-diisocyanate (2,6-TDI); • m-xylylene diisocyanate (m-XDI); symmetrical alicyclic diisocyanate compounds, preferably methylene bis(4-cyclohexylisocyanate) (Hi2MDI); symmetrical aliphatic diisocyanate compounds, preferably hexamethylene diisocyanate (HDI), pentamethylene diisocyanate (PDI); asymmetric aromatic diisocyanate compounds, preferably: 2,4'-diphenylmethylene diisocyanate (2,4'-MDI); 2,4'-dibenzyl diisocyanate (2,4'-DBDI); toluene 2,4-diisocyanate (2,4-TDI); • a trimeric biurea compound, in particular a trimeric biurea compound of a compound chosen from: symmetrical aromatic diisocyanate compounds, preferably: 2,2'-diphenylmethylene diisocyanate (2,2'-MDI) and 4,4'-diphenylmethylene diisocyanate (4,4'-MDI); 4,4'-dibenzyl diisocyanate (4,4'-DBDI); toluene 2,6-diisocyanate (2,6-TDI); m-xylylene diisocyanate (m-XDI); symmetrical alicyclic diisocyanate compounds, preferably methylene bis(4-cyclohexylisocyanate) (Hi2MDI); symmetrical aliphatic diisocyanate compounds, preferably hexamethylene diisocyanate (HDI), pentamethylene diisocyanate (PDI); asymmetric aromatic diisocyanate compounds, preferably: 2,4'-diphenylmethylene diisocyanate (2,4'-MDI); 2,4'-dibenzyl diisocyanate (2,4'-DBDI); • 2,4-toluene diisocyanate (2,4-TDI); - asymmetric alicyclic diisocyanate compounds, preferably isophorone diisocyanate (IPDI), preferably compound (a2) is selected from triphenylmethane-4,4',4”-triisocyanate, 1,1',1”-methylidynetris (4-isocyanatobenzene), HDI isocyanurate, IPDI isocyanurate, PDI isocyanurate, HDI biurea trimer and IPDI biurea trimer, PDI biurea trimer.

3. Copolymer P according to one of claims 1 or 2 for which the polyhydroxylated compound (b) is chosen from: • a compound (b 1) of formula II: [Chem II] HO-LP-OH (II) in which: - L independently represents an oxyalkylene residue; - p independently represents a number ranging from 30 to 1,000; • a compound (b 1) of formula II associated with a non-alkoxylated compound (b2) comprising at least three hydroxyl groups; • a polyalkoxylated compound (b3) comprising at least three hydroxyl groups; • their combinations.

4. Copolymer P according to one of claims 1 to 3 for which compound (b) is chosen from: • a compound (bl) of formula II in which: - L independently represents an oxyethylene residue; or - p independently represents a number ranging from 50 to 400, preferably from 100 to 300; or - L independently represents an oxyethylene residue and p independently represents a number ranging from 50 to 400, preferably from 100 to 300; • a compound (b2) comprising three hydroxyl groups, preferably chosen from glycerol, pentaerythritol and combinations thereof; • a compound (b3) different from compound (b2) and comprising three hydroxyl groups, preferably a compound (b3) chosen from polyethoxylated glycerol, polyethoxylated pentaerythritol and combinations thereof.

5. Copolymer P according to one of claims 1 to 4 for which the compounds (b), (bl) or (b3) independently have a molar mass (Mw) measured by CES ranging from 1,500 to 40,000 g / mol, preferably from 2,000 to 20,000 g / mol, more preferably from 2,000 to 15,000 g / mol or from 2,000 to 12,000 g / mol.

6. Copolymer P according to one of claims 1 to 5 for which: • the dimerization of two identical compounds of formula I leads to a homodimer (cl); or • a compound (c) is a homodimer (cl) is 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 ranging from 2 to 7; or • a compound (c) is a homodimer (cl) is 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 ranging from 5 to 7, preferably from 4 to 6, more preferably 4 or 5.

7. Copolymer P according to one of claims 1 to 5 for which: • the dimerization of two different compounds of formula I leads to a mixture comprising 2 different homodimers (cl) and one heterodimer (c2); or • a mixture of compounds (c) is obtained by dimerization of two different compounds of formula I in which - R independently represents a linear C5-C7-alkyl group; - m independently represents 0 or 1, preferably 0; - n independently represents a number from 2 to 7; or • a mixture of compounds (c) 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 independently represents 0 or 1, preferably 0; - n independently represents a number ranging from 5 to 7, preferably from 4 to 6, more preferably 4 or 5; or • a mixture of compounds (c) comprises a heterodimeric compound (c2) 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; or • a mixture of compounds (c) comprises: • a heterodimeric compound (c2) 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 (cl) 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 (cl) 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.

8. Copolymer P according to one of claims 1 to 7 for which the polymerization reaction uses: - from 10 to 79.9 mol% or from 10 to 74.5 mol%, preferably from 10 to 68 mol% or from 10 to 60 mol%, of monomer (a) or - from 20 to 89.9 mol% or from 25 to 89.5 mol%, preferably from 30 to 88 mol% or from 35 to 85 mol%, of monomer (b), or - from 0.1 to 70 mol% or from 0.5 to 65 mol%, preferably from 2 to 60 mol% or from 5 to 55 mol%, of monomer (c), relative to the total molar quantity of monomers (a), (b) and (c).

9. Copolymer P according to one of claims 1 to 8 for which the polymerization reaction also uses at least one hydrophobic compound (d) different from the compound (c), preferably chosen from a compound of formula (III): [Chem III] RHOEMOPX-OH (HD in which: - q and r, identical or different, independently represent 0 or an integer or decimal number less than 150, q or r 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 C6-C40-alkyl group, linear or branched, a phenyl group, a polyphenyl group, preferably a C10-C30-alkyl group, linear or branched, more preferably a C12-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 mol%,preferably from 0.05 to 20 mol%, in particular from 0.1 to 10 mol%, of compound (d) relative to the quantity, total molar of compounds involved.

10. Rheological control composition comprising at least one copolymer P according to one of claims 1 to 9, optionally treated in an acidic manner leading to a pH lower than 8, preferably to a pH higher than 6, for example by means of an acid, in particular for example a carboxylic acid such as acetic acid or lactic acid.

11. A rheological control composition according to claim 10 also comprising at least one solvent, in particular water or a coalescing solvent, for example glycol, butyl glycol, butyl diglycol, monopropylene glycol, ethylene glycol, ethylene diglycol, Dowanol products with CAS number 34590-94-8, Texanol products with CAS number 25265-77-4; or combined with at least one additive chosen from an amphiphilic compound, in particular a surfactant compound, preferably a hydroxylated surfactant compound, for example alkyl polyalkylene glycol, in particular alkyl polyethylene glycol and alkyl polypropylene glycol; a polysaccharide derivative, for example cyclodextrin, cyclodextrin derivative, polyethers, alkyl glucosides; a hydrotropic compound, an antifoaming agent, a biocidal agent and combinations thereof.

12. An aqueous formulation comprising: - at least one composition according to one of claims 10 or 11; 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 chosen 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 anti-foaming agent, a preservative, a biocidal agent, a spreading agent, a thickening agent, a film-forming copolymer and mixtures thereof.

13. Formulation according to claim 12 for coating, in particular an ink formulation, a varnish formulation, an adhesive formulation, a paint formulation, for example decorative paint or industrial paint.

14. Concentrated aqueous pigment paste comprising at least one co- polymer P according to one of claims 1 to 9 and at least one organic or mineral colored pigment.

15. Method for controlling the viscosity of an aqueous composition comprising the addition of at least one copolymer P according to one of claims 1 to 9 in this composition.

16. A method according to claim 15 wherein the aqueous composition is an aqueous formulation defined according to one of claims 12 or 13.