RHEOLOGY MODIFIER POLYMER

Abstract

The present invention relates to a method for making a direct emulsion of a copolymer in water, characterized in that it comprises the polymerization of at least, expressed as a percentage by weight of each of the monomers based upon the total weight of the monomers: a) 10 to 80% by weight of methacrylic acid and, optionally, of acrylic acid; b) 15 to 80% by weight of at least one non-ionic vinyl monomer; c) 0.05 to 9.5% by weight of 2-acrylamido-2-methylpropane sulfonic acid or a salt thereof; d) 0.5 to 30% by weight of at least one monomer containing at least one hydrophobic group; and e) 0.01 to 5% by weight of at least one crosslinking monomer; said polymerization being carried out in the presence of at least one surfactant.

It also relates to the corresponding new copolymer emulsion in water, a method for thickening an aqueous composition comprising such an emulsion of copolymer and to an aqueous composition comprising such a copolymer emulsion.

Claims

1-17: (canceled)

18. A method for making a direct emulsion of a copolymer in water, wherein the method comprises the polymerization of at least, expressed as a percentage by weight of each of the monomers based upon the total weight of the monomers: a) 10 to 80% by weight of methacrylic acid and, optionally, of acrylic acid; b) 15 to 80% by weight of at least one non-ionic vinyl monomer; c) 0.05 to 9.5% by weight of 2-acrylamido-2-methylpropane sulfonic acid or a salt thereof; d) 0.5 to 30% by weight of at least one monomer containing at least one hydrophobic group; and e) 0.01 to 5% by weight of at least one crosslinking monomer; said polymerization being carried out in the presence of at least one surfactant.

19. The method according to claim 18, wherein the method comprises the polymerization of at least 10.5 to 80% by weight of methacrylic acid and of acrylic acid.

20. The method according to claim 18, wherein the total of a), b), c), d) and e) weight contents is equal to 100%.

21. The method according to claim 18, wherein the total weight amount of methacrylic acid and, optionally, of acrylic acid, ranges from 20% to 50% by weight, based upon the total weight of the monomers forming the copolymer.

22. The method according to claim 18, wherein the non-ionic vinyl monomer is an ester of (meth)acrylic acid.

23. The method according to claim 18 comprising from 50% to 75% of the at least one non-ionic vinyl monomer, based upon the total weight of the monomers forming the copolymer.

24. The method according to claim 18 comprising from 0.1% to 7% by weight of the 2-acrylamido-2-methylpropane sulfonic acid or a salt thereof, based upon the total weight of the monomers forming the copolymer.

25. The method according to claim 18, wherein the monomer containing the at least one hydrophobic group has general structure (III): ##STR00006## wherein: m, n, p and q are integers and m, n, p are inferior to 150, q is superior to 0 and at least one integer from m, n and p is non-zero, Ra has a polymerizable vinylic function, R.sub.1 and R.sub.2 are identical or different and represent hydrogen atoms or alkyl groups, and Rb is a hydrophobic group containing from 6 to at most 36 carbon atoms.

26. A direct emulsion of a copolymer in water, wherein the copolymer is polymerized from a monomer mixture comprising at least, expressed as a percentage by weight of each of the monomers based upon the total weight of monomers: (a) 10 to 80% by weight of methacrylic acid and, optionally, of acrylic acid; (b) 15 to 80% by weight of at least one non-ionic vinyl monomer; (c) 0.05 to 9.5% by weight of 2-acrylamido-2-methylpropane sulfonic acid or a salt thereof; (d) 0.5 to 30% by weight of at least one monomer containing at least one hydrophobic group; and (e) 0.01 to 5% by weight of at least one crosslinking monomer; wherein said emulsion contains at least one surfactant.

27. The emulsion according to claim 26 comprising from 50% to 75% of the at least one non-ionic vinyl monomer, based upon the total weight of the monomers forming the copolymer.

28. A method for thickening an aqueous composition comprising the direct emulsion of a copolymer according to claim 26, comprising adding to said aqueous composition a pH adjusting agent selected from an acidic material, an alkaline material, and mixtures thereof.

29. The method according to claim 28, wherein said aqueous composition further includes at least a surfactant different from the surfactant contained in said emulsion of the copolymer, the different surfactant being selected from anionic, zwitterionic or amphoteric surfactants, cationic or non-ionic surfactants, and combinations thereof.

30. An aqueous composition comprising the copolymer emulsion as claimed in claim 26.

31. The aqueous composition according to claim 30, wherein the aqueous composition has a pH value equal to or lower than 6.

32. The aqueous composition according to claim 30, wherein the aqueous composition comprises an amount of said copolymer effective to impart a yield strength of greater than 0 Pa to the aqueous composition.

33. The aqueous composition according to claim 30, wherein the aqueous composition comprises an amount of said copolymer effective to impart a yield strength of greater than 1 Pa to the composition and the aqueous composition further comprises suspended particles of one or more solid, liquid, or gas that are insoluble or are only partly soluble in the aqueous composition.

34. The composition according to claim 30, wherein the aqueous composition exhibits a clear, transparent visual appearance.

35. The method according to claim 22, wherein the non-ionic vinyl monomer is selected from C.sub.1-C.sub.18-alkyl esters of acrylic acid, C.sub.1-C.sub.18-alkyl esters of methacrylic acid, and mixtures thereof.

36. The method according to claim 22, wherein the non-ionic vinyl monomer is selected from ethyl acrylate, butyl acrylate, methyl methacrylate, and mixtures thereof.

37. The aqueous composition according to claim 31, wherein the pH value ranges from 2 to 5.

Description

EXAMPLES

[0167] In the following examples, the aqueous surfactant formulations incorporating the different copolymer emulsions were prepared according to the following protocol. The amounts are indicated in percent by weight of active material (wt % active) relative to the total weight of the composition.

[0168] The copolymer emulsion, Sodium laureth-2EO sulfate (SLES, as Rhodapex ES-2K) and Cocamidopropylbetaine (CAPB, as Mirataine BET C-30) were added to most part of deionized water under moderate agitation.

[0169] A solution of sodium hydroxide (15%) was slowly added to the mixture, so as to reach a solution pH of about 6.5. Sodium chloride was added if necessary.

[0170] Then, formulation pH was adjusted to pH 4.7-5.0 with a solution of citric acid (15%). 0.5 wt % sodium benzoate (preservative) was added under moderate agitation. Final pH was adjusted to [4.9-5.1] with a solution of sodium hydroxide (15%) or citric acid (15%) and the rest of deionized water available was added up to 100.

[0171] The formulations were centrifuged to remove any entrained air bubbles. The sample jars containing the centrifuged formulations were capped and held for 24 hours after which following characterizations are made.

[0172] Characterizations

[0173] Each of the compositions was tested and evaluated for their clarity, suspending and thickening properties, pursuant to the testing procedure protocols described below.

[0174] Yield Stress (Also Referred to as Yield Strength)

[0175] Flow curves and yield stress measurements are conducted on an advanced rheometer (TA instruments AR2000 Rheometer), using specific protocols: measurements carried out at 25 C. using a 60-mm 2-cone/plate geometry with a 53 m-gap. After a 2-min stabilization step, a stepped flow is applied with a ramp shear rate from 10.sup.3 s.sup.1 to 1 s.sup.1 (20 points per decade in 10 min). A continuous ramp is then applied from 1 s.sup.1 to 1000 s.sup.1 (20 points/decade in 3 min).

[0176] The static yield stress is determined as the value of the applied shear stress beyond which the viscosity starts decreasing. It is usually recognized that suspension properties will increase when yield stress increases.

[0177] Yield stress values greater than or equal to 0.5, preferably greater than or equal 1 are suitable for the desired formulations, in order to obtain suitable suspension properties of pigments, particles, beads, capsules, gas bubbles etc.

[0178] Brookfield Viscosity

[0179] Brookfield Viscosity of the compositions was measured using a Brookfield Viscometer Model RV DVD-I or DVII+ (Brookfield Engineering Laboratories, Inc.) at 10 revolutions per minute (RPM), with spindles 4 or 5. Measurements were conducted at temperature between 19 and 23 C.

[0180] Typical order of magnitude of Brookfield Viscosity (10 rpm) for the desired thickened formulations are 2,500-40,000 mPa.Math.s, preferably 2,500-25,000 mPa.Math.s.

[0181] Transmittance

[0182] The clarity was indicated by transmittance (% T) measurements at 600 nm in 2.5 ml polystyrene cell, 1010 mm, using a UV/VIS spectrometer Lambda Bio 40.

[0183] In the case of the following examples, it is considered that compositions having a transmittance of 88% or more, preferably more than to 90%, were substantially clear.

[0184] Suspension

[0185] Suspension properties of the final formulations were assessed visually by checking the suspension of Polyethylene beads (Metapearls-1 STD Blue) homogeneously dispersed into the considered formulation (0.1 grams of beads in 50 grams of formulation), after storage for three months at 45 C.

Example 1

[0186] Preparation of the Copolymer Emulsions

[0187] The ingredients used are summarized in TABLE 1 below. The polymers of Examples E1-E6, each contained: [0188] optionally first monomeric units derived from acrylic acid (AA), [0189] second monomeric units derived from methacrylic acid (MA), [0190] third monomeric units derived from ethyl acrylate (EA), [0191] optionally fourth monomeric units derived from sodium salt of acrylamide-2-methylpropane sulfonic acid, [0192] fifth monomeric units derived from a monomeric compound according to structure (IV) above, wherein R.sup.19=methyl, i=25, and j=5 (NOPOL polyether monomer), [0193] sixth monomeric units derived from a mixture of (C.sub.16-C.sub.22)alkyl-polyethoxylated methacrylates having an average of 25 ethylene oxide units per molecule, according to structure (V), wherein R.sup.25 is methyl, R.sup.21 is a mixture of linear C.sub.16 alkyl, linear C.sub.18 alkyl, and linear C.sub.22 alkyl groups, p=2, r=25 s=0, and t=1 ((C.sub.16-C.sub.22)alkyl-polyether monomer).

[0194] The NOPOL polyether monomer was introduced in the form of an aqueous solution (NOPOL polyether monomer solution) that contained, based on 100 wt % active of the solution, about 50 wt % active of the NOPOL polyether monomer and about 25 wt % active MA.

[0195] The (C.sub.16-C.sub.22)alkyl-polyether monomer was introduced in the form of an aqueous solution ((C.sub.16-C.sub.22)alkyl-polyether solution) that contained, based on 100 wt % active of the solution, about 50 wt % active of the (C.sub.16-C.sub.22)alkyl-polyether monomer and about 25 wt % active MA.

[0196] In a 1 L jacketed reactor, the water (300.20 gr) and the surfactant ammonium laureth sulfate (Rhodapex AB20ammonium salt of sulphated alcohol ethoxylate, 29 wt % active material in water) (10.34 gr) were added. The reactor contents was heated to 78 C. and purged with N.sub.2. Once temperature was stable, 6.54 g of sodium salt of 2-acrylamido-2-methylpropane sulfonic acid (51 wt % in water), 0.449 g of sodium persulfate dissolved in 5 g of water and 0.05 g of sodium metabisulfite dissolved in 5 g of water were added. Then 25% of a mixture of 90.1 g of ethyl acrylate, 39.8 g of acrylic acid and 0.152 g of trymetylolpropane diallyleter (TMPDE, 90% active material) were continuously added. After the addition of the 25% of the monomer mixture, the remaining 75% mixed with 12.09 g of NOPOL polyether monomer solution as is and 25.06 g of (C.sub.16-C.sub.22)alkyl-polyether solution as is were added. The latex was aged for 30 minutes at 78 C. 0.050 g of sodium persulfate dissolved in 25 g of water were semi continuously added. The reaction contents was cooled down and the reaction vessel emptied.

[0197] Copolymer emulsions referenced E2, E3, E4, E5 and E6 were synthesized using the same process with the different wt % monomer compositions indicated in Table 1 below.

[0198] The amounts of monomers for each of the synthetized copolymer emulsions are expressed as weight percent of active material (wt % active) based upon the total monomer active weight content.

[0199] The amount of surfactant for each of the synthetized copolymer emulsions are expressed as weight percent of active material (wt % active) based upon the total monomer active weight content

TABLE-US-00001 TABLE 1 Copolymer E6 (outside emulsion the (wt %) E1 E2 E3 E4 E5 invention) Acrylic acid 24.68 17.96 11.95 6.12 0 0 (% wt active) Methacrylic 0 6.09 12.14 18.18 24.04 25.31 acid (% wt active) Ethyl acrylate 55.88 56.39 56.72 56.38 56.72 57.14 (% wt active) AMPS salt 2.07 2.10 2.12 2.12 2.10 0 (% wt active) NOPOL 5.63 5.65 5.67 5.67 5.63 5.81 polyether (correspond- (correspond- (correspond- (correspond- (correspond- (correspond- monomer ing to ing to ing to ing to ing to ing to solution (% wt 3.75 wt 3.77 wt 3.78 wt 3.78 wt 3.75 wt 3.87 wt active) % % % % % % (active) (active) (active) of (active) of (active) of (active) of the of the of the the NOPOL the NOPOL the NOPOL NOPOL NOPOL NOPOL polyether polyether polyether polyether polyether polyether monomer monomer monomer monomer and monomer monomer and 1.89 and 1.89 and 1.88 1.94 wt % and 1.88 and 1.88 wt % wt % wt % (active) of MA) wt % wt % (active) of (active) of (active) of (active) (active) MA) MA) MA) of MA) of MA) (C16-C22) 11.66 11.72 11.31 11.43 11.43 11.66 alkyl-polyether (corresponding (corresponding (corresponding (corresponding (corresponding (corresponding monomer to 7.77 wt % to 7.81 wt % to 7.54 wt % to 7.62 wt % to 7.62 wt % to 7.77 wt % solution (active) of the (active) of the (active) of the (active) of the (active) of the (active) of the (% wt active) C16-C22) alkyl- C16-C22) alkyl- C16-C22) alkyl- C16-C22) alkyl- C16-C22) alkyl- C16-C22) alkyl- polyether polyether polyether polyether polyether polyether monomer monomer monomer monomer monomer monomer monomer and monomer and monomer and monomer and monomer and monomer and 3.89 wt % 3.91 wt % 3.77 wt % 3.81 wt % 3.81 wt % 3.89 wt % (active) of MA) (active) of MA) (active) of MA) (active) of MA) (active) of MA) (active) of MA) Crosslinker 0.08 0.08 0.08 0.09 0.08 0.09 TMPDE (% wt active) Rhodapex AB- 1.87 1.88 1.89 1.89 1.89 1.94 20 surfactant (% wt active)

[0200] Results

[0201] Aqueous surfactant formulations F1 to F6 were prepared with the synthetized copolymer emulsions E1 to E6 according to the above-mentioned protocol with the proportions: 2.5 wt % active copolymer emulsion in an aqueous composition containing 9.0 wt % active of SLES and 2.0 wt % active CAPB. pH of the aqueous composition was adjusted to [4.9-5.1] after neutralisation at 6.5.

[0202] The aqueous surfactant formulations were then tested pursuant to the testing procedure protocols described above.

[0203] The results are recorded in Table 2 below.

TABLE-US-00002 TABLE 2 Formulations F1 F2 F3 F4 F5 F6 Copolymer E1 E2 E3 E4 E5 E6 emulsion used Brookfield Yes Yes Yes Yes Yes Yes Viscosity between 2500 and 25000 mPa .Math. s ? Transmittance 93.1 93.4 93.2 91.7 89.6 83.6 (%) Yield Stress 1.1 1.5 1.0 1.4 2.3 4.9 (Pa) Suspension Yes Yes Yes Yes Yes Yes beads ( 3 months 45 C.)

[0204] All formulations have adequate viscosity and suspension properties. The copolymer emulsions of the invention E1 to E5 demonstrate better transmittance indicating better clarity compared to non-conform copolymer emulsion E6.

Example 2

[0205] Preparation of the Copolymer Emulsions

[0206] The ingredients used are summarized in TABLE 3 below. The polymers of Examples E7-E11, each contained: [0207] optionally first monomeric units derived from acrylic acid (AA), [0208] second monomeric units derived from methacrylic acid (MA), [0209] third monomeric units derived from ethyl acrylate (EA), [0210] optionally fourth monomeric units derived from sodium salt of acrylamide-2-methylpropane sulfonic acid, [0211] fifth monomeric units derived from a monomeric compound according to structure (IV) above, wherein R.sup.19=methyl, i=25, and j=5 (NOPOL polyether monomer), [0212] sixth monomeric units derived from a mixture of (C.sub.16-C.sub.22)alkyl-polyethoxylated methacrylates having an average of 25 ethylene oxide units per molecule, according to structure (V), wherein R.sup.25 is methyl, R.sup.21 is a mixture of linear C.sub.16 alkyl, linear C.sub.18 alkyl, and linear C.sub.22 alkyl groups, p=2, r=25 s=0, and t=1 ((C.sub.16-C.sub.22)alkyl-polyether monomer).

[0213] The NOPOL polyether monomer was introduced in the form of an aqueous solution (NOPOL polyether monomer solution) that contained, based on 100 wt % active of the solution, about 50 wt % active of the NOPOL polyether monomer and about 25 wt % active MA.

[0214] The (C.sub.16-C.sub.22)alkyl-polyether monomer was introduced in the form of an aqueous solution ((C.sub.16-C.sub.22)alkyl-polyether solution) that contained, based on 100 wt % active of the solution, about 50 wt % active of the (C.sub.16-C.sub.22)alkyl-polyether monomer and about 25 wt % active MA.

[0215] Copolymer emulsion referenced E7 was prepared according to the following process. In a 1 L jacketed reactor, the water (300.20 g) and 10.34 g of the surfactant ammonium laureth sulfate (Rhodapex AB20 ammonium salt of sulphated alcohol ethoxylate, 29 wt % active material in water) were added. The reactor contents was heated to 78 C. and purged with N.sub.2. Once temperature was stable, 6.0 g of sodium salt of 2-acrylamido-2-methylpropane sulfonic acid (AMPS51 wt % in water), 0.449 g of sodium persulfate dissolved in 5 g of water and 0.05 g of sodium metabisulfite dissolved in 5 g of water were added. Then 25% of a mixture of 88.3 g of ethyl acrylate, 3.0 g of acrylic acid and 35.4 g of methacrylic acid were continuously added. 50% of this monomer mixture mixed with 8 g of NOPOL polyether monomer solution as is and 16 g of (C.sub.16-C.sub.22)alkyl-polyether solution as is were added. Then the last 25% of this monomer mixture with 4 g of NOPOL polyether monomer solution as is, 8.1 g of (C.sub.16-C.sub.22)alkyl-polyether solution as is, and 0.144 g of Trimethylolpropane diallyl ether (TMPDE, 90% active material) were added. The reactor temperature was increased to 87 C. in 30 minutes. Once temperature has been stable at 87 C., 0.23 g of tertbutyl hydroperoxyde TBHP (75% active) was added shot-wise, followed by a continuous addition of 0.16 g of erythorbic acid dissolved in 10 g of water (30 minutes). The latex was aged for 30 minutes at 87 C. After the 30 minute hold, 0.23 g of tertbutyl hydroperoxyde TBHP (75% active) was added shot-wise followed by a continuous addition of 0.16 g of erythorbic acid dissolved in 10 g of water. The reaction contents were cooled down and the reaction vessel emptied.

[0216] Copolymer emulsion referenced E8, E9 and E10 were synthesized using the same process with the different wt % monomer compositions indicated in Table 3 below. Copolymer emulsion referenced E11 were synthesized using the same process, but with sodium lauryl sulfate (Rhodapon LS-92RN) as a surfactant instead of Rhodapex AB20, with the wt % monomer compositions indicated in Table 3 below.

[0217] The amounts of monomers for each of the synthetized copolymer emulsions are expressed as weight percent of active material (wt % active) based upon the total monomer active weight content.

[0218] The amount of surfactant for each of the synthetized copolymer emulsions are expressed as weight percent of active material (wt % active) based upon the total monomer active weight content

TABLE-US-00003 TABLE 3 E10 (outside Copolymer the emulsion E7 E8 E9 invention) E11 Acrylic acid 1.90 1.88 1.90 1.90 1.90 (% wt active) Methacrylic 22.55 22.64 22.54 22.62 22.59 acid (% wt active) Ethyl acrylate 56.26 56.30 56.39 56.30 56.34 (% wt active) AMPS salt 1.95 1.94 1.92 1.93 1.94 (% wt active) NOPOL 5.74 5.70 5.73 5.73 5.70 polyether (corresponding (corresponding (corresponding (corresponding (corresponding monomer to 3.83 wt % to 3.80 wt % to 3.82 wt % to 3.82 wt % to 3.80 wt % solution (% wt (active) of the (active) of the (active) of the (active) of the (active) of the active) NOPOL NOPOL NOPOL NOPOL NOPOL polyether polyether polyether polyether polyether monomer and monomer and monomer and monomer and monomer and 1.91 wt % 1.90 wt % 1.91 wt % 1.91 wt % 1.90 wt % (active) of MA) (active) of MA) (active) of MA) (active) of MA) (active) of MA) (C16-C22) 11.52 11.45 11.43 11.43 11.44 alkyl-polyether (corresponding (corresponding (corresponding (corresponding (corresponding monomer to 7.68 wt % to 7.63 wt % to 7.62 wt % to 7.62 wt % to 7.63 wt % solution (% wt (active) of the (active) of the (active) of the (active) of the (active) of the active) C16-C22) alkyl- C16-C22) alkyl- C16-C22) alkyl- C16-C22) alkyl- C16-C22) alkyl- polyether polyether polyether polyether polyether monomer monomer monomer monomer monomer monomer and monomer and monomer and monomer and monomer and 3.84 wt % 3.82 wt % 3.81 wt % 3.81 wt % 3.81 wt % (active) of MA) (active) of MA) (active) of MA) (active) of MA) (active) of MA) Crosslinker 0.08 0.09 0.09 0.09 0.09 TMPDE (% wt active) Rhodapex AB- 1.84 1.47 0.33 0 0 20 surfactant (% wt active) Rhodapon LS- 0 0 0 0 2.15 92RN surfactant (% wt active)

[0219] Results

[0220] Aqueous surfactant formulations F7 to F11 were prepared with the synthetized copolymer emulsions E7 to E11 according to the above-mentioned protocol with the proportions: 2.5 wt % active copolymer emulsion in an aqueous composition containing 9.0 wt % active of SLES and 2.0 wt % active CAPB. pH of the aqueous composition was adjusted to [4.9-5.1] after neutralisation at 6.5.

[0221] The aqueous surfactant formulations were then tested pursuant to the testing procedure protocols described above.

[0222] The results are recorded in Table 4 below.

TABLE-US-00004 TABLE 4 Formulations F7 F8 F9 F10 F11 Copolymer E7 E8 E9 E10 E11 emulsion used Brookfield Yes Yes Yes Yes Yes Viscosity between 2500 and 25000 mPa .Math. s ? Transmittance 94.1 94.3 89.8 63.7 95.2 (%) Yield Stress (Pa) 2.2 2.1 3.3 4.8 2.25 Suspension Yes Yes Yes Yes Yes beads (3 months 45 C.)

[0223] All formulations have adequate viscosity and suspension properties.

[0224] Formulations F7, F8, F9 and F11 with copolymer emulsions in accordance with the invention have a combination of superior clarity, viscosity and suspension properties.

[0225] However, the copolymer emulsion free of surfactant delivers a decreased transmittance. The formulation is turbid.

Example 3

[0226] Comparison with Benchmark Rheology Modifiers in Rinse-Off Formulations at Different pH

[0227] The use of the copolymer emulsion E7 (prepared according to example 2) was compared with the use of benchmark rheology modifiers Carbopol Aqua SF-2 from Lubrizol and Eliclear 4U from Seppic, in aqueous formulations at different acidic pH.

[0228] Aqueous surfactant formulations were prepared according to the above-mentioned protocol with the proportions: 2.5 wt % active copolymer emulsion in an aqueous composition containing 9.0 wt % active of SLES and 2.0 wt % active CAPB. pH of the aqueous composition was adjusted to 5.0; 4.5 or 4.0 after neutralisation at 6.5.

[0229] The aqueous surfactant formulations were then tested pursuant to the testing procedure protocols described above.

[0230] The results are recorded in Table 5 below.

TABLE-US-00005 TABLE 5 Formulations Comparative Comparative F7 F12 F13 Copolymer emulsion used E7 Carbopol Eliclear 4U Aqua SF-2 pH adjustment at 5.0 Brookfield Viscosity between Yes Yes Yes 2500 and 25000 mPa .Math. s ? Transmittance (%) 94.1 96.6 87.4 Yield Stress (Pa) 2.2 0.8 4.5 Suspension beads (3 months Yes Yes (partial) Yes 45 C.) pH adjustment at 4.5 Brookfield Viscosity between Yes Yes Yes 2500 and 25000 mPa .Math. s ? Transmittance (%) 94.6 95.1 87.1 Yield Stress (Pa) 2.2 1.6 3.9 Suspension beads (3 months Yes Yes Yes 45 C.) pH adjustment at 4.0 Brookfield Viscosity between Yes Yes Yes 2500 and 25000 mPa .Math. s ? Transmittance (%) 94.4 96.2 86.7 Yield Stress (Pa) 2.3 2.0 4.6 Suspension beads (3 months Yes Yes Yes 45 C.)

[0231] At pH 5.0, 4.5 or 4.0, in the considered rinse-off formulations, Eliclear 4U show transmittance below 88%, which corresponds to hazy formulation.

[0232] At pH 5.0; 4.5 or 4.0, copolymer emulsion E7 and commercial Carbopol Aqua SF-2 display transmittance higher than 90%, which corresponds to clear formulations.

[0233] At pH 5.0; 4.5 or 4.0, copolymer emulsion E7 shows a higher yield stress than Carbopol Aqua SF-2, i.e. better suspension ability.

[0234] In conclusion, copolymer emulsion E7 of the invention has better combined yield value and clarity properties.

Example 4

[0235] Aqueous surfactant formulations F14 and F15 were prepared according to the above-mentioned protocol with the proportions indicated in table 6 below. pH of the aqueous formulations was adjusted to around 5 after neutralisation at 6.5.

TABLE-US-00006 TABLE 6 Formulation composition (wt % active content) F14 F15 E7 2.50 2.50 SLES 9.0 9.0 CAPB 2.0 2.0 Sodium chloride 0.0 1.01 Sodium benzoate 0.52 0.53

[0236] The formulations were then tested pursuant to the testing procedure protocols described above.

[0237] The results are recorded in Table 7 below.

TABLE-US-00007 TABLE 7 Characterization F14 F15 pH 5.01 5.06 Brookfield Viscosity (mPa .Math. s) 9880 13860 Transmittance % 94.1 92.2 Yield Stress (Pa) 2.2 2.9 Suspension beads (3 months 45 C.) yes yes

[0238] Formulations containing active sodium chloride also show a high viscosity, a high transmittance superior to 90%, a high yield stress with high suspension ability.

[0239] This demonstrates that the copolymers of the invention are not overly sensitive to salt content, particularly at pH below 6. The formulations containing a copolymer of the invention does not typically undergo undesirable changes in response to relatively small changes in the amount of salts.

Example 5

[0240] Aqueous surfactant formulations F16 and F17 were prepared according to the above-mentioned protocol with the proportions indicated in table 8 below. pH of the aqueous formulations was adjusted to around 5 after neutralisation at 6.5.

TABLE-US-00008 TABLE 8 Formulation composition (wt % active content) F14 F16 F17 E7 2.50 2.52 2.50 SLES 9.0 7.80 6.62 CAPB 2.0 3.16 4.47 Sodium chloride 0.0 0.0 0.0 Sodium benzoate 0.52 0.51 0.53

[0241] The formulations were then tested pursuant to the testing procedure protocols described above.

[0242] The results are recorded in Table 9 below.

TABLE-US-00009 TABLE 9 Characterization F14 F16 F17 pH 5.01 5.07 5.02 Brookfield Viscosity (mPa .Math. s) 9880 12320 17560 Transmittance % 94.1 93.6 90.5 Yield Stress (Pa) 2.2 2.7 3.2 Suspension beads (3 months 45 C.) yes yes yes

[0243] All formulations show a high viscosity, a high transmittance superior to 90%, a high yield stress with high suspension ability.

[0244] This demonstrates that the formulations containing a copolymer of the invention do not typically undergo undesirable changes in response to changes in the surfactant system.

Example 6

[0245] Liquid Hand-Soap Formulation

[0246] The copolymer emulsion E7 (prepared according to example 2), sodium laureth-2EO sulfate (SLES, as Rhodapex ES-2K) and sodium cocoamphoacetate (CAMA, as Miranol Ultra C-32) were added to most part of deionized water under moderate agitation. A solution of sodium hydroxide (15%) was slowly added to the mixture, so as to reach a solution pH of about 6.5. Formulation pH was adjusted to pH 4.7-5.0 with a solution of citric acid (15%). 0.5 wt % sodium benzoate (preservative) was added under moderate agitation. Final pH was adjusted to 5.0 with a solution of sodium hydroxide (15%) or citric acid (15%) and the rest of deionized water available was added up to 100.

[0247] The composition of the hand-soap formulation is summarized in the following Table 10.

TABLE-US-00010 TABLE 10 wt % active Formulation composition content E7 2.48 SLES 9.73 CAMA 2.28 Sodium benzoate 0.50

[0248] The formulation was then tested pursuant to the testing procedure protocols described above.

[0249] The results are recorded in Table 11 below.

TABLE-US-00011 TABLE 11 Characterization pH 5.0 Brookfield Viscosity (mPa .Math. s) 13900 Transmittance % 93.4 Yield Stress (Pa) 2.7 Suspension beads (3 months 45 C.) yes

[0250] Liquid hand-soap formulation shows a high viscosity, a high transmittance superior to 90%, a high yield stress with high suspension ability.

Example 7

[0251] Shampoo

[0252] Ammonium lauryl sulfate (ALS, as Rhodapon ALSA B) and Cocamide monoethanolamine (Cocamide MEA, as Mackamide CMA) were added to half of available amount of deionized water under moderate agitation. The mixture was heated at 60 C. until homogeneous. Cocamidopropylbetaine (CAPB, as Mirataine BET C-30) was added, followed by copolymer emulsion E7 under moderate agitation. A solution of sodium hydroxide (15%) was slowly added to the mixture, so as to reach a solution pH of about 6.5. Formulation pH was adjusted to pH 5.0-5.3 with a solution of citric acid (15%). 0.5 wt % sodium benzoate (preservative) was added under moderate agitation. Final pH was adjusted to 5.3 with a solution of sodium hydroxide (15%) or citric acid (15%) and the rest of deionized water available was added up to 100.

[0253] The composition of the shampoo is summarized in the following Table 12.

TABLE-US-00012 TABLE 12 wt % active Formulation composition content E7 2.06 ALS 10.51 CAPB 2.11 CMEA 1.00 Sodium benzoate 0.52

[0254] The formulation was then tested pursuant to the testing procedure protocols described above.

[0255] The results are recorded in Table 13 below.

TABLE-US-00013 TABLE 13 Characterization pH 5.3 Brookfield Viscosity (mPa .Math. s) 13460 Transmittance % 96.0 Yield Stress (Pa) 1.2 Suspension beads (3 months 45 C.) yes

[0256] The shampoo formulation shows a high viscosity, a high transmittance superior to 90%, a high yield stress with high suspension ability.

Example 8

[0257] Conditioning Shampoo

[0258] Copolymer emulsion E8 was added in deionized water, followed by addition of Ammonium lauryl sulfate (ALS, as Rhodapon ALSA B) under moderate agitation. In a separate vessel, a solution of 6.67 wt % active of Cocamide monoethanolamine (Cocamide MEA, as Mackamide CMA) in deionized water was prepared, under heating at 60 C. Once homogeneous, the solution of Cocamide MEA was cooled down to ambient temperature, and then added to the mixture under moderate agitation. A solution of sodium hydroxide (15%) was slowly added to the mixture, so as to reach a solution pH of about 6.5.

[0259] Cocamidopropylbetaine (CAPB, as Mirataine BET C-30) was then added. Hydroxypropyl guar hydroxypropyltrimonium chloride (HPguarHPTC, as Jaguar C-162) was added under high speed agitation (1000 RPM during 10 minutes), followed by addition of 0.5 wt % sodium benzoate (preservative). Formulation pH was adjusted to pH 5.3 with a solution of citric acid (15%) and the rest of deionized water available was added up to 100.

[0260] The composition of the conditioning shampoo is summarized in the following Table 13.

TABLE-US-00014 TABLE 13 wt % active Formulation composition content E8 2.0 ALS 12.7 CAPB 2.6 CMEA 1.0 HPguarHPTC 0.3 Sodium benzoate 0.5

[0261] The formulation was then tested pursuant to the testing procedure protocols described above.

[0262] The results are recorded in Table 14 below.

TABLE-US-00015 TABLE 14 Characterization pH 5.3 Brookfield Viscosity (mPa .Math. s) 35560 Transmittance % 95.2 Yield Stress (Pa) 1.9 Suspension beads (3 months 45 C.) yes

[0263] Conditioning shampoo formulation shows a high viscosity, a high transmittance superior to 90%, a high yield stress with high suspension ability.

Example 9

[0264] Shampoo and/or Shower Gel Compositions

[0265] The copolymer E8 of the invention can be used in the following formulations.

TABLE-US-00016 TABLE 15 Compositions Constituents A B C D E F G H E8 2.0% 2.0% 2.0% 2.0% 2.0% 2.0% 2.0% 2.0% Ammonium lauryl sulfate (as 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% Rhodapon ALSA B) Cocamidopropylbetaine (as 2.6% 2.6% 2.6% 2.6% 2.6% 2.6% 2.6% 2.6% Mirataine BET C-30) Cocamide monoethanolamine 1.0% 1.0% 1.0% 1.0% 1.0% 1.0% 1.0% 1.0% (as Mackamide CMA) Hydroxypropyl guar 0.3% 0.3% 0.3% 0.3% 0.3% 0.3% 0.3% 0.3% hydroxypropyltrimonium chloride (as Jaguar C-162) 0.6 m Dimethicone emulsion 1% from Mirasil DM-500,000 (Bluestar Silicones) 0.9 m Dimethicone emulsion 1% from Mirasil DM-500,000 (Bluestar Silicones) 2 m Dimethicone emulsion: 1% Mirasil DME-2 (Bluestar Silicones) 30 m Dimethicone emulsion: 1% Mirasil DME-30 (Bluestar Silicones) Amodimethicone 1% Dow Corning 2-8566 Amino Fluid (Dow Corning) Dimethiconol emulsion: 1% Dow Corning 1501 (Dow Corning) Divinyldimethicone/dimethicone 1% copolymer emulsion: Dow Corning HMW 2220 (Dow Corning) PEG/PPG-10/2 Dimethicone: 1% Mirasil DMCP-93 (Rhodia) Fragrance, preserving agents qs qs qs qs qs qs qs qs Demineralized water qsp qsp qsp qsp qsp qsp qsp qsp 100% 100% 100% 100% 100% 100% 100% 100%

Example 10

[0266] Shampoo and/or Shower Gel Compositions

[0267] The copolymer E8 of the invention can be used in the following formulations.

TABLE-US-00017 Compositions Constituents I J K L M N O E8 2.0% 2.0% 2.0% 2.0% 2.0% 2.0% 2.0% Ammonium lauryl sulfate 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% 12.7% (as Rhodapon ALSA B) Cocamidopropylbetaine 2.6% 2.6% 2.6% 2.6% 2.6% 2.6% 2.6% (as Mirataine BET C-30) Cocamide monoethanolamine 1.0% 1.0% 1.0% 1.0% 1.0% 1.0% 1.0% (as Mackamide CMA) Hydroxypropyl guar 0.3% 0.3% 0.3% 0.3% 0.3% 0.3% 0.3% hydroxypropyltrimonium chloride (as Jaguar C-162) Zinc Pyrithione 1% Zinc Omadine (Arch Chemical) Piroctone Olamine 1% Octopirox (Clariant) Selenium sulfide 1% Salicylic acid (Rhodia) 1% Benzophenone-3 1% Uvinul M-40 (BASF) Ethylhexyl Methoxycinnamate 1% Parsol MCX (DSM) Polysilicone-15 1% Parsol SLX (DSM) Fragrance, preserving agents qs qs qs qs qs qs qs Demineralized water qsp qsp qsp qsp qsp qsp qsp 100% 100% 100% 100% 100% 100% 100%