Copolymer having thickening and suspension properties

Abstract

(EN) The invention relates to the field involved in the production of aqueous compositions comprising rheology modifying agents, in particular the production of aqueous detergent or cosmetic compositions having improved, thickening and clarity properties, as well as good suspension properties. In particular, the invention relates to a rheology modifying agent which is a copolymer obtained by means of polymerisation of at least one crosslinking monomer with at least one anionic monomer comprising at least one polymerisable ethylenic unsaturation and at least one hydrophobic non-ionic monomer comprising at least one polymerisable ethylenic unsaturation.

Claims

1. A copolymer (P1), comprising, in polymerized form: (a) an anionic monomer having polymerizable ethylenic unsaturation, comprising acrylic acid, methacrylic acid, an acrylic acid salt, a methacrylic acid salt, or a mixture of two or more of any of these; (b) a hydrophobic nonionic monomer having polymerizable ethylenic unsaturation, comprising a C.sub.1-C.sub.8-alkyl acrylate, C.sub.1-C.sub.8-alkyl methacrylate, C.sub.1-C.sub.8-alkyl maleates, C.sub.1-C.sub.8-alkyl itaconate, C.sub.1-C.sub.8-alkyl crotonate, C.sub.1-C.sub.8-alkyl cinnamate, or a mixture of two or more of any of these: and (c) a monomer of formula (I) ##STR00015## wherein R.sup.1 is independently H or CH.sub.3, R.sup.2 is independently —C(H)═CH.sub.2, —C(CH.sub.3)═CH.sub.2, —C(H)═C(H)C(O)OH, —C(H)═C(H)CH.sub.3, —C(═CH.sub.2)CH.sub.2C(O)OH, or —CH.sub.2C(═CH.sub.2)C(O) OH, L.sup.1 is independently an ethylene, propylene, or butylene group, and n is independently an integer or decimal in a range of from 3.5 to 30.

2. The copolymer of claim 1, wherein the anionic monomer (a) is an anionic monomer comprising a polymerizable vinyl function and a carboxylic acid function, and comprises the acrylic acid and/or the methacrylic acid and optionally further comprises maleic acid, itaconic acid, crotonic acid, an acrylic acid salt, a methacrylic acid salt, a maleic acid salt, an itaconic acid salt, a crotonic acid salt, and/or cinammic acid salt.

3. The copolymer of claim 1, wherein the hydrophobic nonionic monomer (b) is a hydrophobic nonionic monomer comprising a polymerizable vinyl function, and comprises methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, butyl methacrylate, or a mixture thereof.

4. The copolymer of claim 1, wherein the monomer (c) is selected from the group consisting of a compound (c1) of formula (I) wherein R.sup.1 is H, R.sup.2 is —C(H)═CH.sub.2, L.sup.1 is CH.sub.2-CH.sub.2, and n is 10; a compound (c2) of formula (I) wherein R.sup.1 is H, R.sup.2 is —C(CH.sub.3)═CH.sub.2, L.sup.1 is CH.sub.2-CH.sub.2, and n is 3.5; and a compound (c3) of formula (I) wherein R.sup.1 is H, L.sup.1 is CH.sub.2-CH.sub.2, R.sup.2 is —C(CH.sub.3)═CH.sub.2, and n is 10.

5. The copolymer of claim 1, further comprising, in polymerized form: (d) a nonionic monomer, different than from the hydrophobic nonionic monomer (b), comprising a polymerizable vinyl function and a hydrocarbon-based chain comprising at least 10 carbon atoms.

6. The copolymer of claim 1, further comprising, in polymerized form: (e) an ionic or nonionic monomer, different from the hydrophobic nonionic monomer (b), which is at least one selected from the group consisting of: 2-acrylamido-2-methylpropane sulfonic acid or a salt thereof; a telomer, which is unsaturated, of acrylic acid; a monomer of formula (III) ##STR00016## wherein R.sup.3, R.sup.4, and R.sup.5 are independently H or CH.sub.3, and r is independently 1, 2, or 3; a monomer of formula (IV) ##STR00017## wherein R.sup.6, R.sup.7, and R.sup.8 are independently H or CH.sub.3, R.sup.9 is H or CH .sub.3, L.sup.2 is independently a direct bond or an O, C(O)O, CH.sub.2CH.sub.2, or CH.sub.2 group, and L.sup.3 is independently a direct bond or from 1 to 150 alkyleneoxy groups.

7. The copolymer of claim 1 further comprising: (f) a further monomer.

8. The copolymer of claim 1, further comprising, in polymerized form, a monomer (g) selected from the group consisting of; a compound of formula (VI) ##STR00018## wherein L is CH.sub.2, monoalkoxylated CH.sub.2, or polyalkoxylated CH.sub.2, Q is a direct or C(O) bond, R is —C(H)═CH.sub.2, —C(CH.sub.3)═CH.sub.2, —C(H)C(O)OH, —C(H)═C(H)CH.sub.3, —C(═CH.sub.2)CH.sub.2C(O)OH, —CH.sub.2C(═CH.sub.2)C(O)OH, Q.sup.3OQ.sup.4OC(O)C(CH.sub.3)═CH.sub.2, or Q.sup.3OQ.sup.4OC(O)C(H)═CH.sub.2, Q.sup.3 is a divalent residue of an asymmetric diisocyanate compound, and Q.sup.4 is CH.sub.2, CH.sub.2-CH.sub.2, monoalkoxylated CH.sub.2, monoalkoxylated CH.sub.2-CH.sub.2, polyalkoxylated CH.sub.2, or polyalkoxylated CH.sub.2-CH.sub.2; a compound of formula (VI-A) ##STR00019## wherein L is CH.sub.2, monoalkoxylated CH.sub.2, or polyalkoxylated CH.sub.2, R is —C(H)═CH.sub.2, —C(CH.sub.3)═CH.sub.2, —C(H)═C(H)C(O)OH, —C(H)═C(H)CH.sub.3, —C(═CH.sub.2)CH.sub.2C(O)OH, —CH.sub.2C(═CH.sub.2)C(O)OH, Q.sup.3OQ.sup.4OC(O)C(CH.sub.3)═CH.sub.2, or Q.sup.3OQ.sup.4OC(O)C(H)═CH.sub.2, Q.sup.3 is a divalent residue of an asymmetric diisocyanate compound, and Q.sup.4 is CH.sub.2, CH.sub.2-CH.sub.2, monoalkoxylated CH.sub.2, monoalkoxylated CH.sub.2-CH.sub.2, polyalkoxylated CH.sub.2, or polyalkoxylated CH.sub.2-CH.sub.2; and a compound of formula (VI-B) ##STR00020## wherein L is CH.sub.2, monoalkoxylated CH.sub.2, or polyalkoxylated CH.sub.2, R is —C(H)═CH.sub.2, —C(CH.sub.3)═CH.sub.2, —C(H)C(O)OH, —C(H)═C(H)CH.sub.3, —C C(═CH.sub.2)CH.sub.2C(O)OH, —CH.sub.2C(═CH.sub.2)C(O)OH, Q.sup.3OQ.sup.4OC(O)C(CH.sub.3)═CH.sub.2, or Q.sup.3OQ.sup.4OC(O)C(H)═CH.sub.2, Q.sup.3 is a divalent residue of an asymmetric diisocyanate compound, and Q.sup.4 is CH.sub.2, CH.sub.2-CH.sub.2, monoalkoxylated CH.sub.2, monoalkoxylated CH.sub.2-CH.sub.2, polyalkoxylated CH.sub.2, or polyalkoxylated CH.sub.2-CH.sub.2.

9. A method for producing the copolymer of claim 1, the method comprising: producing the copolymer with less than 5 mol relative to the total molar amount of monomers, of at least one monomer of formula (I) ##STR00021## wherein R.sup.1 is independently H or CH.sub.3, R.sup.2 is independently —C(H)═CH.sub.2, —C(CH.sub.3)═CH.sub.2, —C(H)═C(H)C(O)OH, —C(H)═C(H)CH.sub.3, —C(═CH.sub.2)CH.sub.2)CH.sub.2C(O)OH, or —CH.sub.2C(═CH.sub.2)C(O)OH, L.sup.1 is independently an ethylene, propylene, or butylene group, and n is independently an integer or decimal in a range of from 3.5 to 30.

10. A process for producing a copolymer (P1), the process comprising: polymerizing monomers comprising: (a) an anionic monomer having polymerizable ethylenic unsaturation comprising acrylic acid, methacrylic acid, an acrylic acid salt, a methacrylic acid salt, or a mixture of two or more of any of these; (b) a hydrophobic nonionic monomer having polymerizable ethylenic unsaturation, comprising a C.sub.1-C.sub.8-alkyl acrylate, C.sub.1-C.sub.8-alkyl methacrylate, C.sub.1-C.sub.8-alkyl maleates, C.sub.1-C.sub.8-alkyl itaconate, C.sub.1-C.sub.8-alkyl crotonate, C.sub.1-C.sub.8-alkyl cinnamate, or a mixture of two or more of any of these; and (c) a monomer of formula (I) ##STR00022## wherein R.sup.1 is independently H or CH.sub.3; R.sup.2 is independently —C(H)═CH.sub.2, —C(CH.sub.3)═CH.sub.2, —C(H)C(O)OH, —C(H)═C(H)CH.sub.3, —C(═CH.sub.2)CH.sub.2C(O)OH, or —CH.sub.2C(═CH.sub.2)C(O) OH, L.sup.1 is independently an ethylene, propylene, or butylene group, and n is independently an integer or decimal in a range of from 3.5 to 30.

11. A process for producing a copolymer (P2), the process comprising: conducting a polymerization reaction with the copolymer (P1) of claim 1, obtained beforehand by a polymerization reaction.

12. A copolymer (P2) produced by the process of claim 11.

13. The copolymer (P2) of claim 12, wherein a 1° copolymer (P1)/2° copolymer (P 1) weight ratio is between 45/55 and 95/5.

14. An aqueous composition comprising: the copolymer (P2) of claim 12 or the copolymer (P1).

15. A cosmetic composition, comprising: the aqueous composition of claim 14; the copolymer (P1); the copolymer (P2); or both of the copolymer (P1) and the copolymer (P2).

16. The composition of claim 15, having a pH in a range of from 3 to 9.

17. A method for producing an aqueous composition or a cosmetic composition, the method comprising: producing the aqueous composition or the cosmetic composition with the copolymer (P2) of claim 12 and/or the copolymer (P1).

18. The copolymer of claim 1, comprising, in polymerized form, at least 20 mol % of the anionic monomer (a), relative to the total molar amount of monomers.

19. The copolymer of claim 1, comprising, in polymerized form, from 30 to 80 mol % of the hydrophobic nonionic monomer (b), relative to the total molar amount of monomers.

20. The copolymer of claim 1, comprising, in polymerized form, less than 5 mol % of the monomer (c), relative to the total molar amount of monomers.

Description

EXAMPLES

(1) The examples which follow make it possible to illustrate the various aspects of the invention.

(2) The following abbreviations are used: MAA: methacrylic acid, EA: ethyl acrylate, SR 351 from Sartomer: trimethylolpropane triacrylate (TMPTA), Sipomer HPM100 from Solvay-Rhodia: nopol methacrylate 10 OE, Polyglykol B11/50 from Clariant: ethylene oxide-propylene oxide-monobutyl ether, Empicol LXVN from Huntsmann: sodium lauryl sulfate (SDS), Texapon NS0 from BASF: ammonium laureth sulfate at 28% in solution or ammonium lauryl ether sulfate at 28% in solution (SLES), sodium persulfate (NH.sub.4)S.sub.2O.sub.8, compound (d): solution comprising 45% by weight of methacrylic acid, 5% by weight of water and 50% by weight of compound (d2-1) of formula (II) wherein. T.sup.1 represents a —OC(O)C(CH.sub.3)═CH.sub.2 group, T.sup.2 represents a branched hydrocarbon-based chain comprising 16 carbon atoms (2-hexyldecanyl), m represents 25 and p and q represent 0.

Production of the Polymers According to a Semi-Batch Process

(3) The reagents and amounts used are presented in table 1.

(4) In a stirred 1 l reactor heated using an oil bath, the mixture 1 is prepared by introducing deionized water and a solution containing 28% by mass of sodium lauryl ether sulfate (SLES) or sodium lauryl sulfate (SDS), and optionally ethylene oxide-propylene oxide-monobutyl ether.

(5) A mixture 2, referred to as premix, comprising the following, is prepared in a beaker: methacrylic acid, ethyl acrylate, compound (c), or Sipomer HPM100 TMPTA, optionally, compound (d), optionally, deionized water, optionally, solution at 28% of sodium lauryl ether sulfate (SLES) or of sodium, lauryl sulfate (SDS), optionally, ethylene oxide-propylene oxide-monobutyl ether.

(6) This premix is stirred in order to form a monomeric mixture.

(7) Similarly, a comparative premix not comprising compound (c) is prepared.

(8) A solution of initiator 1 comprising ammonium persulfate and deionized water is prepared. A solution of initiator 2 also comprising ammonium persulfate and deionized water is prepared.

(9) The solution of initiator 1 and also the monomer premix is injected, in parallel, over the course of 2 hours, into the reactor heated to the temperature of 85° C.±1° C. Next, over the course of 1 hour, the solution of initiator 2 is injected into the reactor heated to 85° C.±1° C.

(10) Water is optionally added and the mixture is cured for 30 min at the temperature of 85° C.±1° C. The whole mixture is then cooled to ambient temperature.

(11) The polymers according to the invention and the comparative polymers were produced under these conditions by varying the monomer compositions of the monomer premixes. The compositions of the copolymers obtained are given in the table 1.

(12) TABLE-US-00001 TABLE 1 1 2 3 4 5 6 7 8 9 10 11 12 Example According to the invention Comparative Component (c1) (c1) (c1) (c1) (c2) (c2) (c1) (c1) (c1) 0 TMPTA Sipomer (c) HPM100 Mixture 1 Water 400 400 400 400 400 400 400 400 432 432 432 400 SDS 2.6 2.6 2.6 2.6 2.6 2.6 2.6 2.6 0 0 0 2.6 SLES 0 0 0 0 0 0 0 0 9.29 9.29 9.29 0 B11/50 1.1 1.1 1.1 1.1 1.1 1.1 1.1 1.1 0 0 0 1.1 Mixture 2 Water 173.7 173.7 173.7 173.7 173.7 173.7 173.7 173.7 26.00 26.06 172.50 173.7 SDS 1.81 1.81 1.81 1.81 1.81 1.81 1.81 1.81 0 0 0 1.81 SLES 0 0 0 0 0 0 0 0 0 0 6.47 0 B11/50 1.04 1.04 1.04 1.04 1.04 1.04 1.04 1.04 0 0 0 1.04 Compound (a) 105.69 105.69 105.69 105.69 105.69 105.69 105.69 99.74 76.31 76.31 76.66 99.74 MAA Compound (b) EA 191.28 191.28 191.28 191.28 191.28 191.28 191.28 191.28 196.10 196.10 196.82 191.28 Compound (c) 2.75 0.83 1.925 2.33 1.925 1.1 3.44 2.75 1.10 0.00 1.00 2.75 Compound (d2-1) 0 0 0 0 0 0 0 12.8 51.91 51.91 51.91 12.8 Initiator 1 (NH.sub.4).sub.2S.sub.2O.sub.8 0.587 0.587 0.587 0.587 0.587 0.587 0.587 0.587 0.467 0.467 0.467 0.587 Water 58 59 60 61 65 67 62 57 55 55 55 55 Initiator 2 (NH.sub.4).sub.2S.sub.2O.sub.8 0.123 0.123 0.123 *0.123 0.123 0.123 0.123 0.123 0.123 0.123 0.123 0.123 Water 40 40 40 40 40 40 40 40 20 20 20 40 Rinsing or Water 20 20 20 20 20 20 20 20 11.25 15 15 20 adjustment Composition Residue 35.26 35.49 35.36 35.31 35.36 35.46 35.18 34.55 31.11 31.21 31.12 34.55 by mass of compound (a) the polymer MAA % Residue 63.82 64.23 64.00 63.91 64.00 64.17 63.67 62.52 60.73 60.94 60.77 62.52 compound (b) EA Residue 0.92 0.28 0.64 0.78 0.64 0.37 1.15 0.90 0.34 0.00 0.31 0.90 compound (c) Residue 0.00 0.00 0.00 0.00 0.00 0.00 0.00 2.04 7.82 7.85 7.80 2.04 compound (d2-1) Molar Residue 39.05 39.10 39.07 39.06 39.03 39.07 39.04 39.00 37.09 37.12 37.07 39.01 composition compound (a) of the MAA polymer % Residue 60.79 60.85 60.82 60.80 60.75 60.81 60.76 60.70 62.27 62.31 62.25 60.72 compound (b) EA Residue 0.16 0.05 0.11 0.13 0.22 0.12 0.20 0.16 0.06 0.00 0.11 0.13 compound (c) Residue 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.14 0.57 0.57 0.57 0.14 compound (d2-1)

Evaluation of the Properties of the Polymers in an Aqueous Formulation

(13) The aqueous formulation used comprises 2.4% or 3% by weight of polymer (see table 1), 9% by weight of a first surfactant compound (SLES or sodium lauryl ether sulfate), 3% by weight of a second surfactant compound (CAPS or cocamidopropyl betaine) and water (qsf 100% by weight). The pH of the formulation is adjusted to a value of 5, 6 or 7 by adding lactic acid or sodium hydroxide.

(14) The formulations are evaluated for their viscosity, clarity and suspending performance properties.

Viscosity

(15) The viscosity of the formulations is measured using a Brookfield viscometer, model LVT. Before measuring the viscosity, each of the formulations is left to stand for 24 hours at 25° C. The spindle of the viscometer must be centered relative to the opening of the formulation flask. The viscosity is measured at 6 revolutions per minute using the appropriate module. The viscometer is allowed to, revolve until the viscosity value is stabilized.

(16) The copolymer which is a rheology-modifying agent must give the formulation in which it is used a sufficient viscosity. In general, the viscosity desired for thickened formulations should be greater than 4,000 mPa.Math.s, in particular greater than 6,000 mPa.Math.s and more particularly greater than 8,000 mPa.Math.s.

Clarity

(17) The clarity of each formulation is evaluated by measuring the transmittance by means of a UV Genesys 10 UV spectrometer (Cole Parmer), equipped with Rotilabo-Einmal Kuvetten PS cuvettes of 4.5 ml. The apparatus is preheated for 10 minutes before use, then a first measurement is carried out by means of a cuvette filled with 3.8 ml of bi-permutated water.

(18) A measurement is then carried out with a cuvette filled with 3.8 ml of cosmetic formulation to be tested. The transmittance is measured at the wavelength of 500 nm. The higher the transmittance value, expressed as a percentage, the more limpid the cosmetic composition. For a transmittance value at 500 nm of at least 60%, the formulation is limpid.

(19) Suspending Performance Levels

(20) Viscoelasticity measurements are carried out on the formulations using a Haake-Mars III rheometer. The variations in Tan(δ) and in G′ as a function of the strain τ (scanning of 0 dyn/cm.sup.2 to 1000 dyn/cm.sup.2) are measured at 25° C. using a 1° Cone/Plan geometry. The values of Tan(δ) and of G′ at 10 dyn/cm.sup.2 and the value of elastic strength are deduced from this measurement.

(21) As a general rule, the formulations have good suspending properties for combined values of G′>50 Pa, of Tan(δ) <0.55 and of elastic strength >70 dyn/cm.sup.2.

(22) The results obtained are shown in table 2.

(23) It is noted that the copolymer according to the invention makes it possible to advantageously combine performance levels in terms of thickening effect, of clarity and of suspending properties. In other words, it makes it possible to obtain an aqueous formulation having the desired viscosity and comprising a limpid continuous phase and suspended particles distributed homogeneously in the continuous phase.

(24) TABLE-US-00002 TABLE 2 1 2 3 4 5 6 7 8 9 10 11 12 Example According to the invention Comparative Appli- Brookfield 13 900 13 340 12 800 10 060 8200 13 560 11 280 19 080 17 160* 5920* 8000* 2970 cative viscosity results (mPa .Math. s) pH = 5 at 3% Brookfield 26 300 19 600 21 800 25 690 19 400 21 700 24 190 29 800 NA NA NA 1530 (or * at viscosity 2.4% (mPa .Math. s) pH = 6 and at Brookfield 7000 9380 12 420 10 180 11 000 9880 6600 13 840 NA NA NA 20 100 pH = 5) viscosity (mPa .Math. s) pH = 7 Tan (delta)   0.33   0.37  0.33  0.32   0.24   0.35   0.33  0.39  0.36*   1.33*   0.67*   1.89 pH = 7 (* at pH = 5) T at 500 nm (%)  97  96 98 97  92  97  94  98 94*  98*  94*  99 pH = 7 (* at pH = 5) G′ (Pa) pH = 7  52  79 95 84  107  86  64 102 71*   5*  30*  31 (* at pH = 5) Elastic strength  96 95 95  96  96 NA 119 93*   0*  229*   0 (dyn/cm.sup.2) pH = 7 (* at pH = 5)