Patent Application
20110218295
The present invention relates to new associative rheology modifiers, their manufacture and application.
Specific requirements are often placed on cosmetic, pharmaceutical and technical compositions with regard to their rheological properties. They can often only be converted to the desired application form using additives, so-called thickeners. Examples of customary low molecular weight thickeners are, for example, alkali metal and aluminum salts of fatty acids, fatty alcohols or waxes. However, depending on the field of use of the preparation to be thickened, the use of known thickeners is often associated with disadvantages. For example, the thickening effect of such thickeners may not be satisfactory or their incorporation into the preparation may be hindered or completely impossible, for example due to incompatibility. The provision of products with a complex profile of properties using the lowest possible fraction or the fewest possible different active substances often presents difficulties. For example, there is a need for polymers for cosmetic compositions which have good conditioning or film-forming properties and at the same time may serve as thickeners for such compositions. In addition, esthetic requirements are increasingly being placed on cosmetic and pharmaceutical products by consumers. For example, with such products, a preference for clear formulations in the form of gels is currently observed. There is therefore a need for cosmetically and pharmaceutically compatible polymers which are suitable for providing a certain property profile with regard to sensory, setting capabilities and rheology.
In general, polymeric thickeners allow the viscosity to be adjusted depending on the polymers' molecular weight. One disadvantage which often arises when using polymers as thickeners for preparing more highly viscous or gel-like preparations is that as the molecular weight of the polymer increases, its incorporation into the cosmetic composition generally becomes more difficult, and that ultimately often only swelling of the polymer is observed instead of the desired solution.
Polymeric rheology modifiers may be classified as either naturally, or synthetically derived products. Examples of the former include starch, cellulose, alginate, and proteins. These naturally occurring polymers incorporate building blocks of polysaccharide units, or amino acids, to provide efficient, water soluble rheology modifiers. Grafting of selected moieties onto the backbone of the more widely utilized natural products, such as starch and cellulose, provides for numerous modified versions of the products, developed to address specific application requirements.
Three general classes of acrylic-based synthetic polymers comprise a group of products that have been utilized as rheology modifiers in various applications for many years. The first class is based on homopolymers of (meth)acrylic acid and copolymers of (meth)acrylic acid, (meth)acrylate esters, and maleic acid, among many others. This group is typically referred to as the alkali swellable (or soluble) emulsions (ASE). Modification of the structure of ASE polymers by addition of hydrophobic moieties defines the second class of synthetic rheology modifiers known as the hydrophobically modified, alkali swellable emulsions (HASE). This group of polymers, more commonly referred to as associative thickeners, provides the potential for greater control of the compound rheology, over a broader range of shear rates than the traditional ASE class of synthetic polymers. The third class of synthetic rheology modifiers is the hydrophobically modified, ethoxylated urethane resins (HEUR). This group of polymers typically consists of polyethylene glycol units of varying length, connected by urethane linkages, and terminated with hydrophobic end groups. Unlike the ASE and HASE classes, HEUR rheology modifiers are nonionic substances, and are not dependent on pH for activation of the thickening mechanism.
WO 93/22358 (BASF) describes copolymers obtainable by free-radical polymerization of A) 50-99.99% by weight of an olefinically unsaturated C3-C5 monocarboxylic acid, of an olefinically unsaturated C4-C8 dicarboxylic acid or the anhydride thereof or a mixture of such carboxylic acids or anhydrides with B) 0.1-29.95% by weight of an olefinically unsaturated quaternary ammonium compound of the formula I or II
where R1 is C6-C20-alkyl, C6-C20-alkenyl, C5-C8-cycloalkyl, phenyl, phenyl(C1-C12-alkyl) or (C1-C12-alkyl)phenyl, R2 is hydrogen, methyl or phenyl, R3 and R4 are each H or C1-C4-alkyl, X is halogen, C1-C4-alkoxysulfonyloxy or C1-C4-alkanesulfonate, it also being possible for the latter to occur as R3 or R4 with the formulation of a betaine structure, Y is O or NH, and A is C1-C6-alkylene, or a mixture of such ammonium compounds, C) 0 to 49.99% by weight of an acrylate or methacrylate of the formula III
where R1, R2 and Y have the aforementioned meanings, R5 is hydrogen, methyl or ethyl, and n is a number from 0 to 25, D) 0-29.85% by weight of other copolymerizable monomers and E) 0.5-2% by weight of one or more compounds with at least two olefinically unsaturated groups in the molecule as crosslinker.
WO 00/39176 (BF Goodrich) describes a hydrophilic ampholytic polymer formed by copolymerization of 0.05 to 20 mole percent of an anionic monomer having at least one carboxyfunctional group, 10 to 45 mole percent of a cationic monomer having at least one aminofunctional group, 35 to 95 mole percent of a nonionic hydrophilic monomer, 0 to 10 mole percent of a hydrophobic monomer and 0 to 1.5 mole percent of a crosslinking monomer, and wherein the monomers are selected so as to provide the copolymer with a glass transition temperature of above about 50° C. and the cationic monomer and the anionic monomer are present in a ratio of from about 2 to about 16.
WO 01/62809 (BASF) describes cosmetic compositions comprising at least one water-soluble or water-dispersible polymer which comprises, in incorporated form, a) 5 to 50% by weight of at least one α,β-ethylenically unsaturated monomer of the formula I
in which R1 is hydrogen or C1- to C8-alkyl, and X1 is O or NR2, where R2 is hydrogen, C1- to C8-alkyl or C5- to C8-cycloalkyl, b) 25 to 90% by weight of at least one N-vinylamide and/or N-vinyllactam, c) 0.5 to 30% by weight of at least one compound having a free-radically polymerizable, α,β-ethylenically unsaturated double bond and at least one cationogenic and/or cationic group per molecule,d) 0 to 30% by weight of at least one α,β-ethylenically unsaturated monomer of the formula II
in which R3 is hydrogen or C1- to C8-alkyl, X2 is O or NR5, where R5 is hydrogen C1-C8-alkyl or C5-to C8-cycloalkyl, and R4 is hydrogen or a linear C1- to C22-alkyl radical and the salts thereof.
WO 03/053381 (BASF) describes cosmetic compositions which comprise at least one water-soluble or water-dispersible copolymer which is obtainable by free-radical copolymerization of at least one N-vinyllactam, at least one anionogenic monomer and optionally further α,β-ethylenically unsaturated compounds copolymerizable therewith, in the presence of a polymer component with repeat units which have ether groups or which are derived from vinyl alcohol.
WO 2004/058837 (BASF) describes cosmetic or pharmaceutical compositions comprising A) at least one ampholytic copolymer obtainable by free-radical copolymerization of a) at least one compound with a free-radically polymerizable, α,β-ethylenically unsaturated double bond and at least one anionogenic and/or anionic group per molecule, b) at least one compound with a free-radically polymerizable, α,β-ethylenically unsaturated double bond and at least one cationogenic and/or cationic group per molecule, c) at least one α,β-ethylenically unsaturated amide-group-containing compound of the formula R1—CO—NR2R3 in which one of the radicals R1 to R3 is a group of the formula CH2═CR4, where R4═H or C1-C4-alkyl, and the other radicals R1 to R3, independently of one another, are H, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl, where R1 and R2 together with the amide group to which they are bonded may also be a lactam with 5 to 8 ring atoms, where R2 and R3 together with the nitrogen atom to which they are bonded may also be a five-to seven-membered heterocycle, with the proviso that the sum of the carbon atoms of the radicals R1, R2 and R3 is at most 8, or a polyelectrolyte complex comprising at least one of said ampholytic copolymers and at least one further polyelectrolyte different therefrom, and B) at least one cosmetically acceptable carrier.
WO 2006/044193 (ISP) and US 2007/0231286 A1 (ISP) describe a rheology modifier/hair styling resin which is a crosslinked, linear poly(vinyl amide/polymerizable carboxylic acid) copolymer and its use in color cosmetic compositions.
WO 2007/010035 A1 (BASF) describes the use of an anionic or cationic ampholytic copolymer which is obtainable by free-radical copolymerization of a1) at least one compound having a free-radically polymerizable, α,β-ethylenically unsaturated double bond and at least one anionogenic and/or anionic group per molecule, a2) at least one compound having a free-radically polymerizable, α,β-ethylenically unsaturated double bond and at least one cationogenic and/or cationic group per molecule, b) at least one free-radically polymerizable crosslinking compound which contains at least two α,β-ethylenically unsaturated double bonds per molecule, c) if desired in the presence of at least one silicone compound containing a polyether group and/or a free-radically polymerizable olefinically unsaturated double bond, as rheology modifiers for compositions in hair cosmetics.
U.S. Pat. No. 4,230,844 (DuPont) describes thickener polymers comprising (i) about 1-99% by weight of at least one unsaturated carboxylic acid of 3 to 6 carbon atoms, and (ii) about 1-99% by weight of at least one ester of the formula
wherein R and R2 are each hydrogen or methyl, x is a positive integer of 5 to 80, y is an integer of 0 to 20, and R1 is alkyl of 1 to 20 carbon atoms or alkyl phenyl where the alkyl group is from 1 to 20 carbon atoms or alkyl phenyl where the alkyl group is from 1 to 20 carbon atoms.
U.S. Pat. No. 4,138,381 (Du Pont) describes thickeners comprising a polymer dissolved in a solvent at a concentration up to 50% by weight of the composition, the solvent being at least one glycol and containing during manufacture up to 50% by weight, based on the weight of glycol, of water and the polymer consists essentially of (a) about 10 to 98% by weight of at least one unsaturated carboxylic acid of 3 to 6 carbon atoms, (b) about 1 to 50% by weight of at least one alkyl acrylate or alkyl methacrylate wherein the alkyl group is from 1 to 30 carbon atoms, and (c) about 1 to 85% by weight of at least one ester of the formula
wherein R and R2 are each hydrogen or methyl, x is a positive integer of 5 to 80, y is an integer of 0 to 20, and R1 is alkyl of 1 to 20 carbon atoms or alkyl phenyl where the alkyl group is from 1 to 20 carbon atoms, the total adding up to 100%.
U.S. Pat. No. 5,015,708 describes non-crosslinked precipitation terpolymer products produced by polymerizing a reaction mixture of a vinyl lactam, e.g. vinyl pyrrolidone or vinyl caprolactam, a polymerizable carboxylic acid, e.g. acrylic acid or methacrylic acid, and a hydrophobic monomer, e.g. lauryl methacrylate, in a predetermined compositional range, in the presence of a polymerization initiator, and in an aliphatic hydrocarbon solvent, particularly a C3-C10 saturated hydrocarbon, which is branched or unbranched, cyclic or acylic, and, preferably, is heptane or cyclohexane. The terpolymers are obtained in high yield, as a white powder, which can be filtered and dried easily.
U.S. Pat. No. 6,025,431 describes a polymeric rheology modifier (PRM) which has been prepared by polymerizing from about 5 to about 80 weight percent of an acrylate monomer (a) selected from the group consisting of a C1-C6 alkyl ester of acrylic acid and a C1-C6 alkyl ester of methacrylic acid, from about 5 to about 80 weight percent of a monomer (b) selected from the group consisting of a vinyl-substituted heterocyclic compound containing at least one of a nitrogen or a sulfur atom, (meth)acrylamide, a mono- or di-(C1-C4)alkylamino (C1-C4)alkyl (meth)acrylate and a mono or di-(C1-C4) alkylamino (C1-C4)alkyl (meth)acrylamide, and 0 to about 30 weight percent of an associative monomer (c), all percentages based on the total weight of monomer used to prepare the PRM, and a cosmetically-active agent (CAA).
EP 3235 A1 (BASF) describes a water-soluble copolymer which comprises (a) from 80 to 2′ by weight of an ethylenically unsaturated C3- to C5-carboxylic acid, acrylamidodimethylpropanesulfonicacid, vinylsulfonic acid or vinylphosphoric acid, or of an ester the formula
where R is H or —CH3, n is from 1 to 4 and R1 and R2 are alkyls of 1 to 4 carbon atoms, or of mixtures of the said monomers, and (b) from 20 to 98% by weight of a polymerizable ethylenically unsaturated compound of the formula
where R3 is alkyl of 1 to 20 carbon atoms, R4 is H or —CH3, R5 is H, n is from 2 to 100 and m is from 0 to 50.
EP 11806 A1 (Dow Chemical) describes aqueous liquid emulsion polymers prepared by the copolymerization of (A) 15-60 weight percent of a C3-C8 □-ethylenically unsaturated carboxylic acid monomer, preferably acrylic or methacrylic acid or a mixture thereof with itaconic or fumaric acid, (B) 15-80 weight percent of a nonionic copolymerizable C2-C12
□-ethylenically unsaturated monomer, preferably a monovinyl ester such as ethyl acrylate or a mixture thereof with styrene, acrylonitrile, vinyl chloride or vinyl acetate, and (C) 1-30 weight percent of certain nonionic vinyl surfactant esters, such as nonylphenoxypoly(ethyleneoxy)9 ethyl acrylate, to give an emulsion copolymer stable as an aqueous colloidal dispersion at an acid pH lower than about 5.0 but responsive to pH adjustment with base. These emulsion polymers adjusted to a pH of 5.5-10.5 or higher serve as thickeners for aqueous systems including cosmetic products, drilling muds, and particularly aqueous coating compositions such as latex paint.
EP 13836 (Rohm & Haas) describes copolymers containing (1) 20-69.5% by weight of acrylic and/or methacrylic acid; (2) 0.5-25% by weight of monomer of the formula CH2═C(R)—C(O)—O—(CH2CH2O)n—Ro wherein R is H or CH3, n is at least 2 and Ro is C8-C30 alkyl, alkylaryl or polycyclic alkyl; (3) at least 30% by weight of at least one C1-C4 alkyl acrylate and/or methacrylate and (4) 0-0.1% by weight of polyethylenically unsaturated monomer, the total of (1), (2), (3) and (4) being 100%.
EP 1690878 A1 (Rohm & Haas) describes a polymer comprising (a) from 25% to 45% carboxylic acid monomer residues, (b) from 50% to 65% C2-C4 alkyl(meth)acrylate residues, (c) from 2% to 20% of residues of at least one of: (i) an alkyl(meth)acrylate, (ii) a vinyl alkanoate, (iii) an N-vinyl alkylamide, and (iv) an N-alkyl(meth)acrylamide, wherein an alkyl group having from 6-18 carbon atoms is present; and (d) from 0.01% to 2% of residues of at least one crosslinker.
WO 2003/061615 (Noveon) describes an aqueous hair setting composition comprising an effective hair setting amount of a rheology modifying hair setting, alkali-swellable and/or alkali-soluble associative polymer which is the polymerization product of a monomer mixture comprising:
(a) at least one acidic vinyl monomer or a salt thereof;
(b) at least one nonionic vinyl monomer;
(c) a first associative monomer having a first hydrophobic end group;
(d) at least one monomer selected from the group consisting of a second associative monomer having a second hydrophobic end group, a semihydrophobic monomer, and a combination thereof; and, optionally,
(e) a monomer selected from the group consisting of a crosslinking monomer, a chain transfer agent, and a combination thereof;with the proviso that when monomer (d) is solely selected from a second associative monomer, the first and second hydrophobic end groups of associative monomers (c) and (d) are each independently selected from the same or different hydrocarbon classes, and when the first and second hydrophobic end groups are selected from the same hydrocarbon class, the molecular formulas of the hydrophobic end groups differ by at least 8 carbon atoms.
Anionic associative rheologiy modifying polymers are commercially available as e.g. Aculyn® 22 (INCI: Acrylates/Steareth-20 Methacrylate Copolymer; a copolymer of the ester of methacrylic acid and Steareth-20 and one or more monomers of acrylic acid, methacrylic acid or one of their simple esters), Aculyn® 28 (INCI: Acrylates/Beheneth-25 Methacrylate Copolymer; a copolymer of the ester of methacrylic acid and Beheneth-25 and one or more monomers of acrylic acid, methacrylic acid, or one of their simple esters), Aculyn® 88 (INCI: Acrylates/Steareth-20 Methacrylate Crosspolymer; a copolymer of steareth-20 methacrylate and one or more monomers consisting of acrylic acid, methacrylic acid or one of their simple esters, crosslinked with an allyl ether of pentaerythritol or an allyl ether of trimethylolpropane), and Tinovis® GTC (INCI: Acrylates/Beheneth-25 Methacrylate Copolymer).
Although there are plenty of polymeric thickeners for cosmetic use already known and commercially available, there is still a need for thickeners that at the same time can easily be incorporated into cosmetic compositions, enable fast thickening, particularly at pH values in the ranges from 5 to 9, preferable from 6 to 8, and have good film forming and hair-setting properties. Furthermore, long-term stability of such cosmetic compositions combined with tolerance of comparably high salt contents are desired properties of up-to-date polymeric thickeners. Other desired properties are the ability to form clear gels, stabilizing properties for particles, emulsions, and foams, broad pH range stability, peroxide compatibility, shear tolerance, proccessability in the cold, and broad compatibility with other ingredients.
Surprisingly, it has now been found that these objectives are achieved by a polymer comprising as polymerized units
For the purposes of this invention, the term “alkyl” comprises straight-chain and branched alkyl groups. Suitable short-chain alkyl groups are, for example, straight-chain or branched C1-C7-alkyl groups, preferably C1-C6-alkyl groups and particularly preferably C1-C4-alkyl groups. These include, in particular, methyl, ethyl, propyl, isopropyl, n-butyl, 2-butyl, sec-butyl, tert-butyl, n-pentyl, 2-pentyl, 2-methylbutyl, 3-methylbutyl, 1,2-dimethylpropyl, 1,1-dimethylpropyl, 2,2-dimethylpropyl, 1-ethyl-propyl, n-hexyl, 2-hexyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl, 2,3-dimethylbutyl, 1,1-dimethylbutyl, 2,2-dimethylbutyl, 3,3-dimethylbutyl, 1,1,2-trimethylpropyl, 1,2,2-trimethylpropyl, 1-ethylbutyl, 2-ethylbutyl, 1-ethyl-2-methylpropyl, n-heptyl, 2-heptyl, 3-heptyl, 2-ethylpentyl, 1-propylbutyl, octyl.
Suitable longer-chain C8-C30-alkyl groups and C8-C30-alkenyl groups are straight-chain and branched alkyl groups and alkenyl groups. Preference is given here to predominantly linear alkyl radicals as also occur in natural or synthetic fatty acids and fatty alcohols and in oxo alcohols, which may, if appropriate, additionally be mono-, di- or polyunsaturated. These include, for example, n-hexyl(ene), n-heptyl(ene), n-octyl(ene), n-nonyl(ene), n-decyl(ene), n-undecyl(ene), n-dodecyl(ene), n-tridecyl(ene), n-tetradecyl(ene), n-pentadecyl(ene), n-hexadecyl(ene), n-heptadecyl(ene), n-octadecyl(ene), n-nonadecyl(ene), arachinyl(ene), behenyl(ene), lignocerinyl(ene), melissinyl(ene).
Cycloalkyl is preferably C5-C8-cycloalkyl, such as cyclopentyl, cyclohexyl, cycloheptyl or cyclooctyl.
Aryl comprises unsubstituted and substituted aryl groups and is preferably phenyl, tolyl, xylyl, mesityl, naphthyl, fluorenyl, anthracenyl, phenanthrenyl, naphthacenyl and in particular phenyl, tolyl, xylyl or mesityl.
In the text below, compounds which are derived from acrylic acid and methacrylic acid may sometimes be referred to in short by adding the syllable “(meth)” to the compound derived from acrylic acid.
Monomer a): Acrylic Acid
In one embodiment of the invention the polymer comprises as polymerized units of from 25 to 85% by weight of acrylic acid.
In another embodiment of the invention the polymer comprises as polymerized units of from 40 to 60% by weight of acrylic acid.
In a preferred embodiment of the invention the polymer comprises as polymerized units of from 65 to 75% by weight of acrylic acid.
Monomer b): N-Vinyl Pyrrolidone
In one embodiment of the invention the polymer comprises as polymerized units of from 10 to 60% by weight of N-vinyl pyrrolidone.
In another embodiment of the invention the polymer comprises as polymerized units of from 20 to 50% by weight of N-vinyl pyrrolidone.
In still another embodiment of the invention the polymer comprises as polymerized units of from 10 to 25% by weight of N-vinyl pyrrolidone.
Monomer c): Cationic Monomer
The polymers according to this invention comprise as polymerized units of from 0.3 to 10% by weight of at least one cationic monomer.
For the purposes of this invention, the term “cationic monomer” means monomers carrying a cationic charge or monomers carrying groups, preferably amine groups, that can be cationically charged either by protonation or by quatemization with acids or alkylating agents, respectively. In other words, the term “cationic monomer” can be used to describe cationically charged monomers as well as monomers that can be cationically charged.
In one embodiment of the invention monomer c) comprises at least one compound which is chosen from
All the aformentioned monomers may be mono- or dialkylated on a suitable amine nitrogen.
In one embodiment of this invention, preferred monomers c) are N,N-dimethylaminomethyl(meth)acrylate, N,N-dimethylaminoethyl(meth)acrylate, N,N-diethylaminoethyl(meth)acrylate, N,N-dimethylaminopropyl(meth)acrylate, N,N-diethylaminopropyl(meth)acrylate and N,N-dimethylaminocyclohexyl(meth)acrylate. In one embodiment of this invention, preference is given to N,N-dimethylaminoethyl(meth)acrylate.
In another embodiment of this invention, preferred monomers c) are N-[tert-butylaminoethyl(meth)acrylamide, N-[2-dimethylamino)ethyl]acrylamide, N-[2-(dimethylamino)ethyl]methacrylamide, N-[3-(dimethylamino)propyl]acrylamide, N-[3-(dimethylamino)propyl]methacrylamide, N-[4-(dimethylamino)butyl]acrylamide, N-[4-(dimethylamino)butyl]methacrylamide, N-[2-(diethylamino)ethyl]acrylamide, N-[4-(dimethylamino)cyclohexyl]acrylamide and N-[4-(dimethylamino)cyclohexyl]methacrylamide.
In one embodiment of this invention, preference is given to N-[3-(dimethylamino)propyl]methacrylamide (DMAPMAM).
A specific embodiment relates to polymers which comprise as monomer c) N-[3-(dimethylamino)propyl](meth)acrylamide. In another embodiment, monomer c) consists of N-[3-(dimethylamino)propyl](meth)acrylamide.
In another embodiment of this invention, preferred monomers c) are N,N-diallylamines and N,N-diallyl-N-alkylamines
In another embodiment of this invention, preferred monomers c) are vinyl- and allyl-substituted nitrogen heterocycles different from vinylimidazoles, such as 2- and 4-vinylpyridine, 2- and 4-allylpyridine.
In a preferred embodiment of the invention, monomer c) comprises as cationic monomer c) at least one N-vinylimidazole compound of the general formula (II)
wherein R5 to R7, independently of one another, are hydrogen, C1-C4-alkyl or phenyl.
Examples of compounds c) of the general formula (II) are given in Table 1 below:
In a preferred embodiment of the invention, monomer c) is selected from N-vinylimidazole and mixtures comprising N-vinylimidazole.
A particularly preferred embodiment of the invention relates to polymers in which monomer c) is N-vinylimidazole.
In one embodiment of this invention the polymer comprises as polymerized units of from 0.3 to 5% by weight of the at least one cationic monomer c).
In another embodiment of this invention the polymer comprises as polymerized units of from 0.5 to 3% by weight of the at least one cationic monomer c).
In still another embodiment of this invention the polymer comprises as polymerized units of from 0.5 to 2% by weight of the at least one cationic monomer c).
In one embodiment of the invention the molar ratio between acrylic acid a) and monomer c) is at least 10:1. In another embodiment of the invention the molar ratio between acrylic acid a) and monomer c) is at least 20:1. In still another embodiment of the invention the molar ratio between monomer a) and monomer c) is at least 30:1. In still another embodiment of the invention the molar ratio between monomer a) and monomer c) is at least 40:1.
In one embodiment of the invention the molar ratio between monomer a) and monomer c) is at most 120:1. In another embodiment of the invention the molar ratio between monomer a) and monomer c) is at most 100:1.
In another embodiment of the invention the molar ratio between monomer a) and monomer c) is at most 50:1.
In a preferred embodiment of the invention the molar ratio between monomer a) and monomer c) is in the range of from 30:1 to 120:1, more preferred in the range of from 40:1 to 100:1. In another embodiment of the invention the molar ratio between monomer a) and monomer c) is in the range of from 40:1 to 50:1.
Preferably, the cationogenic and/or cationic groups of the monomer c) are nitrogen-containing groups, such as primary, secondary and tertiary amino groups, and quaternary ammonium groups. The nitrogen-containing groups are preferably tertiary amino groups or quaternary ammonium groups. Charged cationic groups can be produced from the amine nitrogens either by protonation with acids or by quaternization with alkylating agents. The acids include, for example, carboxylic acids, such as lactic acid, or mineral acids, such as phosphoric acid, sulfuric acid and hydrochloric acid. Alkylating agents are e.g. C1-C4-alkyl halides or sulfates, such as ethyl chloride, ethyl bromide, methyl chloride, methyl bromide, dimethyl sulfate and diethyl sulfate. A protonation or quaternization preferably takes place after the polymerization.
In one embodiment of this invention, monomers c) are co-polymerized in their substantially non-quaternized form and remain non-quaternized after the polymerization.
In another embodiment of this invention, monomers c) are co-polymerized in their substantially non-quaternized form and at least partly quaternized after the polymerization.
In still another embodiment of this invention, monomers c) are co-polymerized in their substantially non-quaternized form and completely quaternized after the polymerization.
Substantially non-quaternized form of a monomer c) means that at least 90 mole percent, preferably at least 95 mole percent, more preferably at least 99 mole percent, still more preferably at least 99.9 mole percent of monomers c) are not quaternized until after the polymerization.
The term “after the polymerization” means such point in time, when at most 1 weight percent, preferably at most 0.1 weight percent, more preferably at most 0.01 weight percent, still more preferably at most 0.001 weight percent of all initially polymerizable monomers are still in their polymerizable form, i.e. still carrying a monoethylenic unsaturation.
Due to various experimental reasons, there can always be minor portions of monomers c) that are already cationic (i.e. protonated or quaternized) before or during the polymerization although no purposeful protonation/quaternization has been performed.
The polymers according to this invention comprise as polymerized units of from 1 to 6% by weight of at least one of compounds d1) or d2).
In a preferred embodiment of this invention the polymers comprise as polymerized units of from 2 to 4% by weight of at least one of compounds d1) or d2).
wherein
In one preferred embodiment of the invention, R8 is hydrogen, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, n-pentyl or n-hexyl, particularly preferred hydrogen, methyl or ethyl. Most preferably R8 is methyl.
In one preferred embodiment of the invention, k is an integer in the range of from 1 to 500, in particular of from 3 to 250 and 1 is an integer in the range of from 0 to 100.
In one preferred embodiment of the invention, R9 of monomers d1) and d2) is selected from n-octyl, 1,1,3,3-tetramethylbutyl, ethylhexyl, n-nonyl, n-decyl, n-undecyl, tridecyl, myristyl, pentadecyl, palmityl, heptadecyl, octadecyl, nonadecyl, arrachinyl, behenyl, lignocerenyl, cerotinyl, melissinyl, palmitoleinyl, oleyl, linolyl, linolenyl, stearyl, lauryl.
In particularly preferred embodiments of this invention R9 of monomers d1) and d2) is selected from palmityl, heptadecyl, octadecyl, nonadecyl, arrachinyl, behenyl and their binary or tertiary mixtures.
In another preferred embodiment of this invention R9 of monomers d1) and d2) is selected from the binary and tertiary mixtures of the even-numbered alkyl residues like e.g. C16, C18, C20, and C22.
Preferably, X in formula d1) is O or NH.
Suitable polyether (meth)acrylates d1) are, for example, the condensation products of (meth)acrylic acid with polyetherols. Suitable polyetherols can be prepared easily by reacting ethylene oxide, 1,2-propylene oxide and/or epichlorohydrin with a starter alcohol R9—OH. The alkylene oxides can be used individually, alternately one after the other or as mixtures. The polyether (meth)acrylates d1) can be used on their own or in mixtures for the preparation of the polymers according to the invention.
In one embodiment of this invention the polymers comprise as polymerized units at least one compound d1) chosen from polyether (meth)acrylates terminated with C8-C22-alkyl groups.
Preferred monomers d1) according to this invention are esters of methacrylic acid with ethoxylated C16-C18 alkyl alcohols, wherein the degree of ethoxylation (k in formula d1)) is 10 to 40, preferably 20 to 30.
In one embodiment of this invention, the monomers d1) are provided as mixtures with methylmethacrylate and/or methacrylic acid.
In one preferred embodiment of the invention, the commercially available C18-PEG 1100 MA (Plex® 6877-0, CAS number 70879-51-5 (APG 1100 MA), manufacturer: Evonik) is selected as at least one monomer d1).
In another embodiment of the invention, monomer d1) can be prepared as described in U.S. Pat. No. 3,708,445 using alcohols and acids described in column 3, lines 36-75.
This particular monomer d1) is of the formula:
wherein R8 is hydrogen or methyl,
wherein R10 is alkyl of 8 to 20 carbon atoms.
Suitable allyl alcohol alkoxylates d2) are, for example, the etherification products of allyl chloride with corresponding polyetherols. Suitable polyetherols can be prepared easily by reacting ethylene oxide, 1,2-propylene oxide and/or epichlorohydrin with water or a starter alcohol R9—OH. The alkylene oxides can be used individually, alternately one after the other or as a mixture. The allyl alcohol alkoxylates d2) can be used on their own or in mixtures for the preparation of the polymers according to this invention.
The polymers according to this invention comprise in copolymerized form of from 0.01 to 2% by weight of at least one crosslinking agent e) (crosslinker). Preferred crosslinkers are compounds with at least two polymerizable, ethylenically unsaturated, nonconjugated double bonds.
Suitable crosslinkers e) are e.g. (meth)acrylic esters, allyl ethers or vinyl ethers of at least dihydric alcohols. The OH groups of the parent alcohols here may be completely or partially etherified or esterified; however, the crosslinkers comprise at least two ethylenically unsaturated groups.
Examples of the parent alcohols are dihydric alcohols, such as 1,2-ethanediol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 2,3-butanediol, 1,4-butanediol, but-2-ene-1,4-diol, 1,2-pentanediol, 1,5-pentanediol, 1,2-hexanediol, 1,6-hexanediol, 1,10-decanediol, 1,2-dodecanediol, 1,12-dodecanediol, neopentyl glycol, 3-methylpentane-1,5-diol, 2,5-dimethyl-1,3-hexanediol, 2,2,4-trimethyl-1,3-pentanediol, 1,2-cyclohexanediol, 1,4-cyclohexanediol, 1,4-bis(hydroxymethyl)cyclohexane, hydroxypivalic neopentyl glycol monoester, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis[4-(2-hydroxypropyl)phenyl]propane, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, tetrapropylene glycol, 3-thiopentane-1,5-diol, and polyethylene glycols, polypropylene glycols and polytetrahydrofurans with molecular weights of in each case 200 to 10000. Apart from the homopolymers of ethylene oxide and propylene oxide also block copolymers of ethylene oxide or propylene oxide or copolymers which comprise incorporated ethylene oxide and propylene oxide groups can be used. Examples of parent alcohols with more than two OH groups are trimethylolpropane, glycerol, pentaerythritol, 1,2,5-pentanetriol, 1,2,6-hexanetriol, triethoxycyanuric acid, sorbitan, sugars, such as sucrose, glucose, mannose. The polyhydric alcohols can also be used following reaction with ethylene oxide or propylene oxide as the corresponding ethoxylates or propoxylates. The polyhydric alcohols can also firstly be converted into the corresponding glycidyl ethers by reaction with epichlorohydrin. Preference is given to ethylene glycol di(meth)acrylate and polyethylene glycol di(meth)acrylates.
Further suitable crosslinkers e) are the vinyl esters or the esters of monohydric, unsaturated alcohols with ethylenically unsaturated C3-C6-carboxylic acids, for example acrylic acid, methacrylic acid, itaconic acid, maleic acid or fumaric acid. Examples of such alcohols are allyl alcohol, 1-buten-3-ol, 5-hexen-1-ol, 1-octen-3-ol, 9-decen-1-ol, dicyclopentenyl alcohol, 10-undecen-1-ol, cinnamyl alcohol, citronellol, crotyl alcohol or cis-9-octadecen-1-ol. However, it is also possible to esterify the mono-hydric, unsaturated alcohols with polybasic carboxylic acids, for example malonic acid, tartaric acid, trimellitic acid, phthalic acid, terephthalic acid, citric acid or succinic acid.
Further suitable crosslinkers e) are esters of unsaturated carboxylic acids with the above-described polyhydric alcohols, for example of oleic acid, crotonic acid, cinnamic acid or 10-undecenoic acid.
Suitable crosslinkers e) are also straight-chain or branched, linear or cyclic, aliphatic or aromatic hydrocarbons which have at least two double bonds which, in the case of aliphatic hydrocarbons, must not be conjugated, e.g. divinylbenzene, divinyltoluene, 1,7-octadiene, 1,9-decadiene, 4-vinyl-1-cyclohexene, trivinylcyclohexane or polybutadienes with molecular weights of from 200 to 20000.
Also suitable as crosslinkers e) are the acrylamides, methacrylamides and N-allylamines of at least difunctional amines. Such amines are, for example, 1,2-diaminomethane, 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,6-diaminohexane, 1,12-dodecanediamine, piperazine, diethylenetriamine or isophoronediamine. Likewise suitable are the amides of allylamine and unsaturated carboxylic acids, such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, or at least dibasic carboxylic acids as have been described above.
In addition, triallylamine and triallylmonoalkylammonium salts, e.g. triallylmethylammonium chloride or methyl sulfate, are suitable as crosslinker e).
Also suitable are N-vinyl compounds of urea derivatives, at least difunctional amides, cyanurates or urethanes, for example of urea, ethyleneurea, propyleneurea or tartardiamide, e.g. N,N′-divinylethyleneurea or N,N′-divinylpropyleneurea.
Further suitable crosslinkers e) are divinyldioxane, tetraallylsilane or tetravinylsilane.
It is of course also possible to use mixtures of the abovementioned compounds e).
In one preferred embodiment of this invention, crosslinker e) is at least one of ethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylates, pentaerythritol triallyl ether, methylenebisacrylamide, N,N′-divinylethyleneurea, triallylamine and triallylmonoalkylammonium salts.
In one preferred embodiment of this invention, crosslinker e) is or comprises pentaerythritol triallyl ether (PETAE, CAS No. 1471-17-6).
The polymers of this invention comprise as polymerized units of from 0.2 to 5% by weight of at least one further monomer f) comprising a group of formula (I)
wherein
Preferably the at least one monomer f) is chosen from compounds of the general formula (Ia)
wherein
In one particularly preferred embodiment of this invention, monomer f) is or comprises 2-(2-oxo-1-imidazolidinyl)ethylmethacrylate (CAS No. 86261-90-7), also known as ureido methacrylate (UMA):
In one embodiment of this invention, the polymers can also contain structural units resulting from byproducts of the synthesis of ureido methacrylate, in particular hydroxyethylethyleneurea (CAS No. 3699-54-5) and N-(methacryloyloxyethyl)-N′-(methacryloyl)ethyleneurea (CAS No. 157312-17-9), as described in DE 4301673, the disclosure of which is hereby incorporated as reference.
Preferred polymers of this invention comprise as polymerized units of from 0.5 to 2% by weight of 2-(2-oxo-1-imidazolidinyl)ethylmethacrylate (ureido methacrylate, UMA).
The polymers according to this invention comprise as polymerized units of from 0 to 30% by weight of further monomers g) different from a) to f). In one embodiment of the invention, the polymers comprise as polymerized units of from 1 to 20% by weight of such further monomers g). In still another embodiment of the invention, the polymers comprise as polymerized units of from 1 to 10% by weight of such further monomers g).
In one embodiment of the invention, at least one monomer g) is chosen from the group consisting of methyl(meth)acrylate, ethyl(meth)acrylate, n-propyl(meth)acrylate, isopropyl(meth)acrylate, methyl ethacrylate, ethyl ethacrylate, n-propyl ethacrylate, isopropyl ethacrylate, n-butyl ethacrylate, tert-butyl ethacrylate, isobutyl ethacrylate, n-butyl(meth)acrylate, tert-butyl(meth)acrylate, isobutyl(meth)acrylate, sec-butyl(meth)acrylate, 2-pentyl(meth)acrylate, 3-pentyl(meth)acrylate, isopentyl acrylate, neopentyl acrylate, n-octyl(meth)acrylate, 1,1,3,3-tetramethylbutyl(meth)acrylate, ethylhexyl(meth)acrylate, n-nonyl(meth)acrylate, n-decyl(meth)acrylate, n-undecyl(meth)acrylate, tridecyl(meth)acrylate, myristyl(meth)acrylate, pentadecyl(meth)acrylate, palmityl(meth)acrylate, heptadecyl(meth)acrylate, nonadecyl(meth)acrylate, arrachinyl(meth)acrylate, behenyl(meth)acrylate, lignocerenyl(meth)acrylate, cerotinyl(meth)acrylate, melissinyl(meth)acrylate, palmitoleinyl(meth)acrylate, oleyl(meth)acrylate, linolyl(meth)acrylate, linolenyl(meth)acyrlate, stearyl(meth)acrylate, lauryl(meth)acrylate, phenoxyethyl acrylate, 4-t-butylcyclohexyl acrylate, cyclohexyl(meth)acrylate, ureido(meth)acrylate, tetrahydrofurfuryl(meth)acrylate and mixtures thereof.
One preferred embodiment of the invention is a polymer as described before, wherein at least one monomer g) is chosen from esters of □-ethylenically unsaturated mono- and dicarboxylic acids with C1-C8-alkanols.
Preferably, at least one monomer g) is chosen from C1-C6 alkyl(meth)acrylates, still more preferred C1-C4 alkyl(meth)acrylates, e.g. from the group consisting of methyl(meth)acrylate, ethyl(meth)acrylate, n-propyl(meth)acrylate, isopropyl(meth)acrylate, methyl ethacrylate, ethyl ethacrylate, n-propyl ethacrylate, isopropyl ethacrylate, n-butyl ethacrylate, tert-butyl ethacrylate, isobutyl ethacrylate, n-butyl(meth)acrylate, tert-butyl(meth)acrylate, isobutyl(meth)acrylate, sec-butyl(meth)acrylate.
In one preferred embodiment of the invention, at least one monomer g) is chosen from the group consisting of methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, tert-butyl methacrylate, isobutyl methacrylate, sec-butyl methacrylate and mixtures thereof.
In another embodiment of the invention, at least one monomer g) is chosen from compounds of the general formula VI
where R1 is a group of the formula CH2═CR4— where R4═H or C1-C4-alkyl and R2 and R3 are, independently of one another, H, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl or R2 and R3 together with the nitrogen atom to which they are bonded are a 5- to 8-membered nitrogen heterocycle or
R2 is a group of the formula CH2═CR4— and R1 and R3 are, independently of one another, H, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl or R1 and R3 together with the amide group to which they are bonded are a lactam having 5 to 8 ring atoms with the proviso that monomer g) is different from any of the monomers a) to f).
In one embodiment of the invention, preferred monomers g) are N-vinyllactams different from any of the monomers a) to f). Suitable monomers g) are unsubstituted N-vinyllactams and N-vinyllactam derivatives, which can, for example, have one or more C1-C6-alkyl substituents, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl etc. These include, for example, N-vinylpiperidone, N-vinylcaprolactam, N-vinyl-5-methyl-2-pyrrolidone, N-vinyl-5-ethyl-2-pyrrolidone, N-vinyl-6-methyl-2-piperidone, N-vinyl-6-ethyl-2-piperidone, N-vinyl-7-methyl-2-caprolactam, N-vinyl-7-ethyl-2-caprolactam etc. and mixtures thereof.
In one embodiment of the invention, preferred monomers g) are N-vinylcaprolactam, N-vinylformamide, acrylamide, N,N-dimethylacrylamide or mixtures thereof.
In still another embodiment of the invention suitable monomers g) are the amides of (meth)acrylic acid different from any of the monomers a) to f). Such amides are, for example, (meth)acrylamide, N-methyl(meth)acrylamide, N-ethyl(meth)acrylamide, N-n-propyl(meth)acrylamide, N-i-propyl(meth)acrylamide, N-(n-butyl)(meth)acrylamide, N-(sec-butyl)(meth)acrylamide, N-(tert-butyl)(meth)acrylamide, N-(n-pentyl)(meth)acrylamide, N-(n-hexyl)(meth)acrylamide, N-(n-heptyl)(meth)acrylamide, N-(n-octyl)(meth)acrylamide, N-(tert-octyl)(meth)acrylamide N-(1,1,3,3-tetramethylbutyl)(meth)acrylamide, N-ethylhexyl(meth)acrylamide, N-(n-nonyl)(meth)acrylamide, N-(n-decyl)(meth)acrylamide, N-(n-undecyl)(meth)acrylamide, N-tridecyl(meth)acrylamide, N-myristyl(meth)acrylamide, N-pentadecyl(meth)acrylamide, N-palmityl(meth)acrylamide, N-heptadecyl(meth)acrylamide, N-nonadecyl(meth)acrylamide, N-arrachinyl(meth)acrylamide, N-behenyl(meth)acrylamide, N-lignocerenyl(meth)acrylamide, N-cerotinyl(meth)acrylamide, N-melissinyl(meth)acrylamide, N-palmitoleinyl(meth)acrylamide, N-oleyl(meth)acrylamide, N-linolyl(meth)acrylamide, N-linolenyl(meth)acrylamide, N-stearyl(meth)acrylamide, N-lauryl(meth)acrylamide.
In still another embodiment of the invention suitable monomers g) are 2-hydroxyethylacrylamide, 2-hydroxyethylmethacrylamide, 2-hydroxyethylethacrylamide, 2-hydroxypropylacrylamide, 2-hydroxypropylmethacrylamide, 3-hydroxypropylacrylamide, 3-hydroxypropylmethacrylamide, 3-hydroxybutylacrylamide, 3-hydroxybutylmethacrylamide, 4-hydroxybutylacrylamide, 4-hydroxybutylmethacrylamide, 6-hydroxyhexylacrylamide, 6-hydroxyhexylmethacrylamide, 3-hydroxy-2-ethylhexylacrylamide and 3-hydroxy-2-ethylhexylmethacrylamide.
In still another embodiment of the invention, at least one monomer g) is chosen from vinyl acetate, vinyl propionate, vinyl butyrate, ethylene, propylene, isobutylene, butadiene, styrene, α-methylstyrene, acrylonitrile, methacrylonitrile, vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride and mixtures thereof.
In still another embodiment of the invention, at least one monomer g) different from acrylic acid is chosen from monomers with a free-radically polymerizable, α,β-ethylenically unsaturated double bond and at least one anionogenic and/or anionic group per molecule. Such monomers g) include monoethylenically unsaturated mono- and dicarboxylic acids having 3 to 25, preferably 3 to 6, carbon atoms, which can also be used in the form of their salts or anhydrides. Examples thereof are methacrylic acid, ethacrylic acid, α-chloroacrylic acid, crotonic acid, maleic acid, maleic anhydride, itaconic acid, citraconic acid, mesaconic acid, glutaconic acid, aconitic acid and fumaric acid. Such monomers g) also include the half-esters of monoethylenically unsaturated dicarboxylic acids having 4 to 10, preferably 4 to 6, carbon atoms, e.g. of maleic acid, such as monomethyl maleate. Such monomers g) also include monoethylenically unsaturated sulfonic acids and phosphonic acids, for example vinylsulfonic acid, allylsulfonic acid, sulfoethyl acrylate, sulfoethyl methacrylate, sulfopropyl acrylate, sulfopropyl methacrylate, 2-hydroxy-3-acryloxypropylsulfonic acid, 2-hydroxy-3-methacryloxypropylsulfonic acid, styrenesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, vinylphosphonic acid and allylphosphonic acid. Such monomers g) also include the salts of the abovementioned acids, in particular the sodium, potassium and ammonium salts, and the salts with amines. Such monomers g) can be used as they are or as mixtures with one another. The weight fractions given all refer to the acid form.
In one embodiment of the invention the component g) is chosen from methacrylic acid, ethacrylic acid, a-chloroacrylic acid, crotonic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, citraconic acid, mesaconic acid, glutaconic acid, aconitic acid, 2-acrylamido-2-methylpropanesulfonic acid, vinylphosphonic acid and mixtures thereof.
In one preferred embodiment of the invention, at least on monomer g) is selected from methacrylic acid, ethacrylic acid, a-chloroacrylic acid, crotonic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, citraconic acid, mesaconic acid, glutaconic acid, aconitic acid and mixtures thereof.
In one embodiment of this invention, the at least one monomer g) is or comprises methyl methacrylate (MMA).
In another embodiment of this invention, the at least one monomer g) is or comprises methacrylic acid (MAA).
In still another embodiment of the invention, the at least one monomer g) is or comprises a mixture of methacrylic acid (MAA) and methyl methacrylate (MMA).
In one embodiment of the invention, monomers d) and g) are used as mixtures for the manufacture of the polymers. Such mixtures of monomers d) and g) are for example mixtures containing methacrylic ester of an ethoxylated (25 mol EO) C16-C18 fatty alcohol spectrum and methylmethacrylate (like e.g. Plex®6877-O) or mixtures comprising C16-C18-(EO)25 methacrylate and methacrylic acid (like e.g. Lutencryl® 250).
In one embodiment of the invention, monomers f) and g) are used as mixtures for the manufacture of the polymers. Such mixtures of monomers f) and g) are for example mixtures containing 2-(2-oxo-1-imidazolidinyl)ethylmethacrylate and methylmethacrylate (like e.g. Plex® 6844-O, N-(2-Methacryloyloxyethyl)ethylene urea 25% by weight in methylmethacrylate).
The following table shows exemplary compositional ranges of monomers a) to g) for six polymers Ito IV according to this invention. The numbers are in % by weight with the proviso that a) to g) add up to a total of 100% by weight; a) is Acrylic acid, b) is N-vinyl pyrrolidone, c) is preferably N-vinyl imidazole, d) is preferably C16-C18 PEG-25 methacrylate, i.e. monomer d) according to formula d1) wherein R8 is Methyl, X is Oxygen, k is about 25, l is zero, R9 is a mixture of C16 alkyl and C18 alkyl; e) is preferably pentaerythritol triallyl ether (PETAE); f) is preferably 2-(2-oxo-1-imidazolidinyl)ethylmethacrylate (CAS No. 86261-90-7), also known as ureido methacrylate (UMA) and g) is preferably methyl methacrylate and/or methacrylic acid.
One embodiment of the invention are polymers comprising as polymerized units
Still another embodiment of the invention are polymers comprising as polymerized units
The polymers according to the invention are preferably manufactured by the method of precipitation polymerization.
The invention thus further provides a method for manufacturing the polymers according to the invention wherein the polymerization is a precipitation polymerization.
In a specific embodiment of the precipitation polymerization use is made of at least two free-radical initiators whose decomposition temperatures and/or half-lives thereof at a certain polymerization temperature are different from one another. As a result, copolymers with particularly low residual monomer contents can be achieved. This is the case, particularly if the initiator that decomposes at the higher temperature is added before the polymer has finished precipitating, preferably before the polymer has started precipitating.
During precipitation polymerization the monomers are soluble in the reaction medium which comprises the monomers and the solvent but not the resulting polymer. The resulting polymer becomes insoluble under such polymerization conditions and precipitates. Thereby it is possible to obtain copolymers with higher molecular weights compared to other polymerization processes, e.g. through solution polymerization. Such copolymers having relatively high molecular weights are particularly advantageous as rheology modifiers, in particular as thickeners.
The precipitation polymerization preferably takes place in a solvent, in which each of the monomers used is soluble (at 20° C. and 1 bar) in an amount of at least 10% by weight to give a solution visibly clear to the human eye.
The precipitation polymerization takes place, for example, in esters such as ethyl acetate or butyl acetate and/or hydrocarbons such as cyclohexane or n-heptane as solvents. In one embodiment of the invention mixtures of ethyl acetate and cyclohexane are used as solvent.
The resulting polymer particles precipitate from the reaction solution and may be isolated by known methods such as filtration at reduced pressure.
The polymerization temperatures are preferably in a range from about 30 to 120° C., particularly preferably from 40 to 100° C.
Suitable Initiators for the free-radical polymerization are peroxo and/or azo compounds customary for this purpose, for example alkali metal or ammonium peroxydisulfates, diacetyl peroxide, dibenzoyl peroxide, succinyl peroxide, di-tert-butyl peroxide, tert-butyl perbenzoate, tert-butyl perpivalate, tert-butyl peroxy-2-ethylhexanoate, tert-butyl permaleate, cumene hydroperoxide, diisopropyl peroxydicarbamate, bis(o-toluoyl)peroxide, didecanoyl peroxide, dioctanoyl peroxide, dilauroyl peroxide, tert-butyl perisobutyrate, tert-butyl peracetate, di-tert-amyl peroxide, tert-butyl hydroperoxide, 2,2′-Azobis(2.4-dimethyl valeronitrile), Azobis(2-amidinopropane)dihydrochloride, 2-2′-Azobis(2-methylbutyronitrile) (Wako® V65), tert.butyl peroctoate (CAS No 13467-82-8), 2,5-Dimethyl-2,5-bis(t-butylperoxy)hexane (Trigonox® 101).
To produce polymers with minimized residual monomer contents, the first polymerization (main polymerization) may be followed by an afterpolymerization step. For such afterpolymerization the same or a different initiator system as for the main polymerization may be used. Preferably the temperature of the afterpolymerization step is equal to, preferably higher than the main polymerization temperature. The reaction temperature during the main polymerization is preferably at most 100° C. and during the afterpolymerization preferably at most and 130° C.
In a specific embodiment at least two free radical initiators which permit an essentially independent initiation in at least two phases are used for the preparation of the polymers according to the invention. Thereby polymers with particularly low residual monomer contents can be achieved.
US 2008/0199416 A1, [0494] to [0508], which is herewith incorporated by reference, gives a detailed description of such a kind of process.
After polymerization the precipitated polymer is isolated from the reaction mixture. Therefore any method known to the skilled person can be used. Such methods are filtration, centrifugation, evaporation of the solvent or combinations of these methods. The polymers can be further purified by conventional washing steps with the same solvents that have been used for the polymerization itself.
Resulting dry polymer powders can advantageously be converted to an aqueous solution or dispersion by dissolution or redispersion, respectively, in water. Pulverulent copolymers have the advantage of better storability and easier transportability and usually exhibit a lower propensity for microbial attack.
The acid groups of the monomers or polymers can be partially or completely neutralized with a base. Bases which can be used for the neutralization of the polymers are alkali metal bases such as sodium hydroxide solution, potassium hydroxide solution, sodium carbonate, sodium hydrogencarbonate, potassium carbonate or potassium hydrogencarbonate and alkaline earth metal bases, such as calcium hydroxide, calcium oxide, magnesium hydroxide or magnesium carbonate and also amines. Suitable amines are, for example, C1-C6-alkylamines, preferably n-propylamine and n-butylamine, dialkylamines, preferably diethylpropylamine and dipropylmethylamine, trialkylamines, preferably triethylamine and triisopropylamine. Preference is given to amino alcohols, e.g. trialkanolamines, such as triethanolamine, alkyldialkanolamines, such as methyl- or ethyldiethanolamine and dialkylalkanolamines, such as dimethylethanolamine, and also 2-amino-2-methyl-1-propanol. Particularly for use in hair treatment compositions, 2-amino-2-methyl-1-propanol, 2-amino-2-ethylpropane-1,3-diol, diethylaminopropylamine and triisopropanolamine have proven particularly useful for the neutralization of the polymers comprising acid groups. The neutralization of the acid groups can also be carried out with the aid of mixtures of two or more bases, e.g. mixtures of sodium hydroxide solution and triisopropanolamine. Depending on the intended used, the neutralization can take place partially or completely.
In one embodiment of this invention, the acrylic acid monomers are at least partially neutralized before polymerization. In one embodiment of this invention, the acrylic acid monomers are at least partially neutralized before polymerization with (NH4)HCO3.
In another embodiment of this invention, the acrylic acid monomers are at least partially neutralized before polymerization with Triethanolamin.
In one preferred embodiment of the invention the precipitation polymerization is carried out in the presence of at least one surfactant. Preferably, this surfactant has an HLB value of less than or equal to 10.
Using the HLB-value (according to W. C. Griffin, J. Soc. Cosmetic Chem. 1 (1949) 311), emulsifiers can be classified according to the ratio of hydrophilic groups to lipophilic groups (HLB=hydrophilic-lipophilic balance).
Suitable surfactants with an HLB value of less than or equal to 10 are described, for example, in Karl-Heinz Schrader, Grundlagen and Rezepturen der Kosmetika [Fundamentals and Formulations of Cosmetics], 2nd edition, Verlag Hüthig, Heidelberg, pp. 395-397, to which reference is made here in its entirety.
The determination of the HLB value of emulsifiers is known to the person skilled in the art and is described, for example, on p. 394 of the abovementioned literature reference.
Further suitable surfactants with an HLB value of less than or equal to 10 are listed, for example, in U.S. Pat. No. 4,375,533, column 7, II. 26-60, to which reference is made here in its entirety. The use of surfactants in the precipitation polymerization of crosslinked polyacrylic acid is already described in U.S. Pat. No. 4,420,596 and U.S. Pat. No. 4,375,533.
The invention thus also provides a method as described above where the precipitation polymerization is carried out in the presence of at least one surfactant which is chosen from linear block copolymers with a hydrophobic structural unit with a length of more than 5 nm (calculated by the law of cosines), which are defined by the following formula:
Cw—(B-A-By)x-Dz
The invention further provides a method as described above where the precipitation polymerization is carried out in the presence of at least one surfactant chosen from random comb copolymers which are defined by the following formula:
R1—(Z)m-(Q)n-R2
In one preferred embodiment of the invention the surfactants are selected from 12-hydroxystearic acid block copolymers, further preferably 12-hydroxystearic acid block copolymers with polyethylene oxide. The 12-hydroxystearic acid block copolymers are particularly preferably ABA block copolymers.
Useful surfactants are disclosed in EP 584771 B1, page 23, lines 2 to 37, which is hereby incorporated by reference.
In another embodiment of the invention the surfactant is selected from the group consisting of
Other surfactants are copolymers of polydimethylsiloxanes and organic glycols like e.g. substances with the INCI name PEG/PPG-25/25 dimethicone (e.g. Belsil® DMC 6031) and dimethicone copolyol acetate (e.g. Belsil® DMC 6032).
Another suitable commercially available dimethicone PEG-7 phosphate (INCI) is e.g. Pecosil® PS-100.
Other suitable commercially available dimethicones are aminoalkyl subsituted dimethicones like e.g. Methoxy PEG/PPG-7/3 Aminopropyl Dimethicone (Abil® Soft AF 100 by Evonik). Aminoalkyl subsituted surfactants enable higher solid contents during the precipitation polymerization compared to the use of non aminated surfactants.
In one preferred embodiment of this invention, the monomers are polymerized by a precipitation polymerization in the presence of Methoxy PEG/PPG-7/3 Aminopropyl Dimethicone.
In another preferred embodiment of this invention, the monomers are polymerized by a precipitation polymerization in the presence of PEG/PPG-25/25 dimethicone.
In still another preferred embodiment of this invention, the monomers are polymerized by a precipitation polymerization in the presence of Leophen RW ECO (mixture of different ethoxilated long chain fatty alcohols, BASF).
Commercially available polyesters comprising polyethylene glycol that may be used as surfactants in the precipitation polymerization are block copolymers of the Hypermer® brand, in particular the grades B239, B246, B261, B234, LP6, A-109, A-409 (described in EP 584771 B1, page 10, lines 25-42).
Commercially available polyoxyethylene-glycerol-fatty-acid esters also suitable as surfactants are e.g. polyglyceryl-2 dipolyhydroxystearates (INCI) such as Dehymuls® PGPH (Cognis).
Other suitable surfactants are compounds with the INCI names PEG-7 Hydrogenated Castor Oil, such as Arlacel® 989, Cremophor® WO7 (BASF) or Dehymuls® HRE 7 (Cognis), PEG-2 Hydrogenated Castor Oil such as Arlacel® 582, sorbitan monooleate/propylglyceryl 4/3-ricinoleate, such as Arlace® 1689 (Croda), sorbitan stearate and sucrose cocoate such as, for example, Arlartone® 2121 (Croda), sorbeth-20 beeswax such as, for example, Atlas G-1726 (Croda).
Another suitable surfactant is a polyamide wax like e g Kahl Wax 6635 (Kahl & Co).
Other suitable commercially available natural waxes are e.g. mixtures of fatty acid esters, fatty acid and fatty alcohol, such as, for example, beeswax, berry wax, rice wax (Kahl & Co). Suitable beeswaxes are in particular those with the CAS numbers 8006-40-4 (white) or 8012-89-3. Suitable beeswaxes bear the INCI (EU) names Cera Alba, synthetic beeswax, PEG-7 dimethicone beeswax. Particularly suitable beeswaxes are those with the INCI EU name Cera Alba.
Suitable berry waxes are e.g. those with the INCI name Rhus Verniciflua Peel Wax (Berry Wax 6290 (Kahl & Co) or Botaniwax® OT (Botanigenics, Inc)).
Suitable rice waxes are in particular those with CAS number 8016-60-2 or the INCI name Oryza Sativa (rice) bran wax. Such rice waxes are available commercially as Cerewax® (Chemyunion Quimica LTDA), ESP® Rice Bran Wax (Earth Supplied Products, LLC), Florabeads® RBW (Floratech Americas), Naturebead® R20 (Micro Powders, Inc. Personal Care Division), Oryza Soft® “COS” (Cosmetochem International Ltd.), ORYZA® Wax (Ichimaru Pharcos Company, Ltd.), Ricebran Wax SP 8000 (Strahl & Pitsch, Inc.), Rice Wax No. 1 (Tri-K Industries), Rice Wax 2811 (Kahl).
The amount of surfactant present during the precipitation polymerization is in the range from 0.001 to 50% by weight, preferably from 0.01 to 20% by weight and particularly preferably in the range from 0.1 to 10% by weight, based on the total amount of 100% by weight of the components a) to g).
On account of their thickening effect, the polymers obtainable by the method according to the invention can be used as the sole gel former in cosmetic preparations. Moreover, they are also suitable for use in combination with customary gel formers.
The polymers according to the invention can be used, in particular as thickeners, in aqueous preparations in the sectors of household, personal care, building industry, textiles, for paper coating slips, pigment printing pastes, aqueous colors, leather-treatment compositions, cosmetic formulations, pharmaceutical products and agrochemicals.
Furthermore, the polymers of this invention are easy to handle, allow for use of continuous production processes with use of in-line static mixers, can be processed with membrane pumps and, when diluted, with turbine mixers and high speed propellers, are able to formulate clear products, can be used with electrolytes, support the stabilization of hydrophobic (low solubility) components, are compatible with nonionic, anionic, zwitterionic and some cationic surfactants, are able to stabilize suspensions, are mild, soft, non-greasy, non-sticky, stable in pH 5.5 to 12 formulations, thicken and stabilize hydrogen peroxide, and allow a flexible choice of the preservative system.
Another embodiment of this invention are cosmetic preparations comprising the polymers according to the invention.
Non-limiting examples for cosmetic preparations comprising the polymers of this inventions are anti-dandruff shampoos, bath foams, curl activators, depilatories, emulsifier free formulations, foaming facial cleansers, hair styling gels, liquid soaps, lotions, moisturizing creams, shampoos, shower gels, skin masks, waterless hand cleaners, and wave sets.
The invention is illustrated in more detail by reference to the following nonlimiting examples.
Preferably, the polymers of this invention are manufactured by precipitation polymerization.
Copolymer of AA/VP/VI/Lutencryl 250/Plex 6844-O/PETAE//Belsil® 6031 (77/12/1/8/2/1.5% w/w)
A stirred reaction vessel was filled with the initial charge, kept under nitrogen atmosphere and the initial charge was heated to 70° C. Feed 1 was added continuously during 3 hours and Feed 2 was added continuously during 5 hours. After completion of Feed 1, Feed 3 was added continuously during 1.5 hours. After completion of Feed 2, the reaction mixture was heated to 75° C. and kept at 75° C. for another 3 hours before heating it to 100° C. and keeping it at 100° C. for another 4 hours.
The reaction mixture was afterwards cooled, filtered, washed with ethyl acetate/cyclohexane and then dried at 80° C./vacuum during 24 hours.
All monomer amounts given in the following table are in weight-%.
In the following, the term “Polymer selected from No. 1 to 35” means any of the Polymers No 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35.
Phase 1 is weighed and homogenized with stirring at a temperature in the range from 20 to 50° C. After about 3 hours, a milky dispersion forms. Triethanolamine is added with stirring. After about 2 hours, a (virtually) homogeneous, high-viscosity gel is formed. Phase 2 is then stirred slowly into phase 1. The gel is stirred at room temperature for a further hour. This produces a stable, clear gel.
Phase 1 is weighed and homogenized with stirring at a temperature in the range from 20 to 50° C. After about 3 hours, a milky dispersion forms. Triethanolamine is added with stirring. After about 2 hours, a (virtually) homogeneous, high-viscosity gel is formed. Phase 2 is then stirred slowly into phase 1. The gel is stirred at room temperature for a further hour. This produces a stable, clear gel.
Phase 1 is weighed and homogenized with stirring at a temperature in the range from 20 to 50° C. After about 3 hours, a milky dispersion forms. Triethanolamine is added with stirring. After about 2 hours, a (virtually) homogeneous, high-viscosity gel is formed. Phase 2 is then stirred slowly into phase 1. The gel is stirred at room temperature for a further hour. This produces a stable, substantially clear gel.
Phase 1 is weighed and homogenized with stirring at a temperature in the range from 20 to 50° C. After about 3 hours, a milky dispersion forms. Triethanolamine is added with stirring. After about 2 hours, a (virtually) homogeneous, high-viscosity gel is formed.
Phase 2 is then stirred slowly into phase 1. The gel is stirred at room temperature for a further hour. This produces a stable, clear gel.
Phase 1: Stir polymer into water. With stirring, the polymer is neutralized with triethanolamine and dissolved. Slowly stir phase 2 into phase 1. Bottle and add propellant gas.
Phase 1: Stir polymer into water. With stirring, the polymer is neutralized with triethanolamine and dissolved. Slowly stir phase 2 into phase 1. Bottle and add propellant gas.
Weigh in and, with stirring, dissolve phases 1 and 2 separately and mix. Slowly stir phase 2 into phase 1.
Weigh in and dissolve phases 1 and 2 separately with stirring, and mix. Slowly stir phase 2 into phase 1.
| Number | Date | Country | |
|---|---|---|---|
| 61309459 | Mar 2010 | US |
