Method for preparing poly(oxyethylene)acrylic acid polymers with high solids and low viscosity

Abstract

This invention provides methods for preparing aqueous compositions, comprising, in the presence of one or more initiators, at a pH of 1 to 5, polymerizing an aqueous medium and an aqueous monomer mixture of one or more acrylic or vinyl macromonomers containing oxidized olefinic groups in the presence of one or more fluids containing carboxylic acid groups selected from copolymerizable olefinically unsaturated carboxylic acids, polymeric polycarboxylic acids, and mixtures thereof, to form a brush polymer containing oxidized olefinic side chain groups, wherein the polymerization is carried out at a solids content in the range of 8% to 60% by weight, and compounding one or more aromatic cofactors with the aqueous composition. Furthermore, this invention provides aqueous compositions of brush polymers containing oxidized olefinic side chain groups, these aqueous compositions having more than one phase domain and significantly reduced viscosity, enabling processing with much less energy input or water waste.

Description

[0001] This invention relates to methods for preparing aqueous compositions, methods comprising polymerizing a mixture of one or more macromonomers containing oxidized olefinic groups in the presence of one or more fluids containing carboxylic acid groups selected from copolymerizable olefinic unsaturated carboxylic acids, polymerizable polycarboxylic acids, or mixtures thereof, to form a brush polymer containing oxidized olefinic side chain groups, wherein polymerization is carried out at a pH of 1 to 5, and to aqueous compositions comprising a brush polymer containing oxidized olefinic side chain groups and one or more aromatic cofactors, such as additive concentrates for cement. More specifically, the present invention relates to methods comprising polymerizing a mixture of one or more aqueous monomers containing oxidized olefinic groups of acrylic or vinyl macromonomers in the presence of one or more fluids containing carboxylic acid groups, selected from copolymerizable olefinically unsaturated carboxylic acids, polymeric polycarboxylic acids, or mixtures thereof, wherein the polymerization is carried out at a pH of 1 to 5, or preferably at a pH of 1 to 4.8; and, more specifically, the present invention relates to aqueous compositions comprising one or more brush polymers containing oxidized olefinic side chain groups, one or more aromatic cofactors, and one or more fluids containing carboxylic acid groups, selected from copolymerizable olefinically unsaturated carboxylic acids, polymeric polycarboxylic acids, or mixtures thereof, which are part of the brush polymer containing oxidized olefinic side chain groups. The compositions of the present invention can be used as thickeners and water-retaining compositions, such as, preferably, aqueous additive concentrates or powder compositions for cement-containing compositions.

[0002] Cellulose, including cellulose ethers, is well known as a viscosity modifier (VMA) additive due to its thickening and water-retaining properties upon the introduction of water. They can be used in concrete mixtures, such as cementing casings used in oil and gas production, and in mortars derived from dry mixes, such as cement-based tile adhesives (CBTA). Their water-retaining properties allow for wet application of mortar to absorbent substrates such as stone, stone structures, concrete, concrete bricks, or clay brick walls, and allow for proper setting before the mortar dries. Furthermore, the thickening and water-retaining properties provided by cellulose ethers are dose-dependent, enabling shear thinning and thus allowing for highly controllable viscosity of compositions containing cellulose ethers during use. However, cellulose ethers are known to delay the cement setting reaction, resulting in lower strength properties in cement products. It is desirable to provide synthetic polymers as a means to enhance water retention in cement products without delaying cement setting.

[0003] Methoxylated poly(ethylene glycol) methacrylate (MPEGMA) polymers, along with β-naphthalenesulfonate (BNS), have been proposed as alternatives to cellulose ether-containing water-retaining agents for use in cement compositions. However, significant viscosity buildup occurs during the synthesis of MPEGMA polymers, resulting in high viscosity in water (e.g., exceeding 1 x 10⁻⁶ at only 10 wt% solids). 4 The concentration of cP makes it unsuitable for commercial production. Drastically reducing the synthetic solids to 5% by weight would undesirably result in low reactor yields and high energy requirements for removing any additional amount of water from the composition.

[0004] U.S. Patent Publication No. 2017 / 0240476A1 to Baumann et al. discloses compositions comprising aqueous solutions or powders, these compositions comprising one or more nonionic or substantially nonionic vinyl or acrylic brush polymers having side-chain or side-chain polyether groups, one or more aromatic cofactors containing one or more phenolic groups or one or more aromatic groups combined with at least one sulfate group, and additionally, one or more polycarboxylic acid ether copolymer water-reducing agents. The compositions can be used in cement. However, even at unacceptably low solids contents, high, unprocessable viscosity results are obtained when preparing the brush polymers and their compositions.

[0005] The inventors sought to solve the problem of providing an aqueous polymer composition and a method for preparing such an aqueous composition, which, when used as a viscosity modifier in a cement admixture, provides thickening and water-retaining properties of cellulose ethers at an acceptable solids content and without uncontrolled viscosity buildup during composition preparation. Summary of the Invention

[0006] According to the present invention, the aqueous composition used as a thickener and water-retaining composition comprises an aqueous medium, preferably an aqueous medium substantially free of organic solvents; one or more brush polymers containing oxidized olefin side chain groups, comprising one or more acrylic or vinyl macromonomers containing oxidized olefin chain groups in polymeric or copolymeric form, and polymeric residues of an initiator.

[0007] One or more aromatic cofactors; and

[0008] One or more fluids containing carboxylic acid groups, selected from:

[0009] As part of a brush polymer containing oxidized olefin side chain groups, olefin-bonded unsaturated carboxylic acids (preferably acrylic acid or methacrylic acid), polymeric polycarboxylic acids (preferably polyacrylic acid or polymethacrylic acid, or more preferably polyacrylic acid), or mixtures thereof in copolymer form;

[0010] The composition has a pH of 1 to 5, or preferably 1 to 4.8, and furthermore, the composition is substantially free of salt or contains no added salt, except for any one or more initiators or their polymerization byproducts. Still additionally, in the aqueous composition according to the invention, the aqueous medium is at least 90% by weight, or preferably at least 98% by weight, or more preferably at least 99% by weight of water. The aqueous composition of the invention may contain polymerization residues of one or more initiators, such as thermal initiators or redox initiators, or preferably, one or more thermal initiators, such as those present in an amount up to 1% by weight based on the total solids of the brush polymer containing olefinic side chain groups.

[0011] According to the present invention, the aqueous composition comprises the following molar ratio:

[0012] The total molar number of carboxylic acids is defined as the total molar number of olefinically unsaturated carboxylic acid monomers used to prepare one or more brush polymers containing olefinically oxidized side chain groups, plus the total molar number of olefinically unsaturated carboxylic acid monomers used to prepare one or more polymeric polycarboxylic acids, and, if any polymeric polycarboxylic acid is not an addition polymer, the total molar number of carboxylic acid groups in the total amount of one or more polymeric polycarboxylic acids.

[0013] The total molar number of olefin oxides is determined as the total molar number of one or more acrylic or vinyl macromonomers containing olefin oxide side chain groups used to prepare one or more brush polymers containing olefin oxide side chain groups, multiplied by the average number of olefin oxide chain groups in the total amount of acrylic or vinyl macromonomers containing olefin oxide chain groups, as reported by the macromonomer manufacturer.

[0014] The ratio is in the range of 0.1:1 to 10:1, or preferably 0.2:1 to 5:1.

[0015] The aqueous compositions of the present invention may comprise storage-stable aqueous mixtures or additive concentrates having a solids content in the range of 8% by weight or more, or preferably 10% by weight or more, or preferably up to 60% by weight, or more preferably 45% by weight or less, or more preferably 12% by weight or more, or even more preferably 30% by weight or more, or 8% to 60% by weight, or preferably 10% to 60% by weight, or more preferably 12% to 45% by weight. Furthermore, the aqueous compositions may comprise storage-stable dry powder compositions, such as those used as additives. The dry powder compositions according to the present invention may also comprise hydraulic cement powder.

[0016] Preferably, the brush polymer containing olefin side chain groups according to the present invention comprises a C1 to C4 alkoxy poly(C2 to C4 alkylene glycol) (meth) acrylate polymer or a copolymer thereof in copolymer form with one or more olefinically unsaturated carboxylic acids, or more preferably, an alkoxy poly(ethylene glycol) (meth) acrylate polymer or a copolymer thereof in copolymer form with one or more olefinically unsaturated carboxylic acids, or even more preferably, a methoxy poly(ethylene glycol) (meth) acrylate (MPEGMA) polymer or a copolymer thereof with acrylic acid or methacrylic acid.

[0017] According to another aspect of the invention, a method for preparing an aqueous composition comprises polymerizing an aqueous medium (preferably an aqueous medium substantially free of organic solvents) and a mixture of one or more aqueous monomers containing oxidized olefinic groups, of an acrylic or vinyl macromonomer, in the presence of a fluid containing carboxylic acid groups selected from copolymerizable olefinically unsaturated carboxylic acids (preferably acrylic acid or methacrylic acid), polymeric polycarboxylic acids (preferably polyacrylic acid or polymethacrylic acid, or more preferably polyacrylic acid), or mixtures thereof, to form a brush polymer containing oxidized olefinic side chain groups. The polymerization may be carried out at a pH of 1 to 5, or preferably 1 to 4.8, in the presence of one or more initiators, such as thermal initiators or redox initiators, preferably one or more thermal initiators. The polymerization of the present invention is carried out at a solids content in the range of 8% by weight or more, or preferably 10% by weight or more, or preferably up to 60% by weight, or more preferably 45% by weight or less, or more preferably 12% by weight or more, or even more preferably 30% by weight or more, or preferably 10% by weight to 60% by weight, or more preferably 12% by weight to 45% by weight. The polymerization of the present invention is carried out in the presence of one or more initiators, based on a total weight of at most 1% by weight, or 0.01% by weight to 0.6% by weight, of monomers used to prepare one or more brush polymers containing oxidized olefin side chain groups. Additionally, in the polymerization of the present invention, the aqueous medium of the aqueous monomer mixture is at least 90% by weight, or preferably at least 98% by weight, or more preferably at least 99% by weight, of water. The method according to the invention may also include drying the aqueous brush copolymer composition to form a dry powder, or may further include compounding one or more aromatic cofactors with the aqueous composition.

[0018] Furthermore, in the polymerization of the aqueous monomer mixture according to the present invention, the molar ratio is:

[0019] The total molar number of carboxylic acids is determined as the total molar number of olefinically unsaturated carboxylic acid monomers used in the polymerization of one or more acrylic or vinyl macromonomers containing oxidized olefinic groups, plus the total molar number of carboxylic acid groups used to prepare one or more polymeric polycarboxylic acids, and, if any polymeric polycarboxylic acid is not an addition polymer, the total molar number of carboxylic acid groups in one or more polymeric polycarboxylic acids.

[0020] The total molar number of olefin oxides is determined as the total molar number of olefin oxides used to prepare a brush polymer of one or more acrylic or vinyl macromonomers containing olefin oxide groups, or the total molar number of acrylic or vinyl macromonomers multiplied by the average number of olefin oxide groups in the total amount of acrylic or vinyl macromonomers containing olefin oxide groups, as reported by the macromonomer manufacturer.

[0021] The ratio is in the range of 0.1:1 to 10:1, or preferably 0.2:1 to 5:1.

[0022] In the polymerization of the aqueous monomer mixture according to the present invention, based on the total weight of the monomers used to prepare the brush polymer containing olefin side chain groups, the total amount of acrylic or vinyl macromonomers containing olefin side chain groups is in the range of 20% to 100% by weight, or preferably 30% to 98% by weight, or preferably 97% by weight or less, or more preferably 50% by weight or more, or even more preferably 65% ​​by weight or more.

[0023] In the polymerization of the aqueous monomer mixture according to the present invention, the total amount (in solids) of one or more fluids containing carboxylic acid groups is based on the total weight of one or more brush polymers containing olefinic side chain groups plus one or more polymeric polycarboxylic acids in the range of 2% to 80% by weight, or preferably 2% to 70% by weight, or preferably 50% by weight or less, or more preferably 35% by weight or less, or even more preferably 3% by weight or greater. Preferably, in the polymerization, the aqueous monomer mixture is substantially free of salt or contains no added salt, except for any one or more initiators or their polymerization byproducts.

[0024] Preferably, in the polymerization of the present invention, the aqueous monomer mixture comprises a C1 to C4 alkoxy poly(C2 to C4 alkylene glycol) (meth) acrylate polymer as one or more acrylic or vinyl macromonomers, or a mixture thereof with one or more olefinically unsaturated carboxylic acids; or more preferably, it comprises an alkoxy poly(ethylene glycol) (meth) acrylate polymer or a mixture thereof with one or more olefinically unsaturated carboxylic acids; or even more preferably, it comprises a methoxy poly(ethylene glycol) (meth) acrylate (MPEGMA) polymer or a mixture thereof with acrylic acid or methacrylic acid.

[0025] According to the methods of the invention, these methods may further include, after polymerization, drying or obtaining one or more brush polymers and one or more aromatic cofactors as separate powders, and then mixing them to form a dry powder blend. Alternatively, the methods of the invention may include a wet process of adding one or more brush polymers containing olefin side chain groups, one or more aromatic cofactors, or mixtures thereof, to an aqueous composition in any order after polymerization to form a stable aqueous composition. The wet process may also include adding one or more polycarboxylic acid ether copolymer water-reducing agents to an aqueous composition containing a brush polymer containing olefin side chain groups or a mixture thereof with one or more aromatic cofactors.

[0026] Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “the” include plural referents. Unless otherwise defined, the terms used herein have the same meaning as commonly understood by those skilled in the art.

[0027] Unless otherwise specified, any term containing parentheses may alternatively refer to the entire term as if it did not contain parentheses, as well as the same term contained within parentheses, and combinations of each alternative. Thus, the term "(meth)acrylate" in alternatives includes methacrylates, or acrylates, or mixtures thereof.

[0028] The endpoints of all ranges involving the same component or property include endpoints and can be combined independently. Thus, for example, the disclosed range of solid content in the range of 8 wt% or more, or preferably 10 wt% or more, or more preferably 12 wt% or more, or preferably up to 60 wt%, or even more preferably 30 wt% or more, or preferably up to 60 wt%, or even more preferably 45 wt% or less, or even more preferably 30 wt% or more, or preferably 10 wt% to 60 wt%, or more preferably 12 wt% to 45 wt%, or even more preferably 30 wt% to 45 wt%, refers to 8 wt% to 60 wt%, or 8 wt% to 10 wt%, or 8 wt% to 12 wt%, or 8 wt% to 30 wt%. The content of any or all solids in the range of % or 8 wt% to 45 wt%, or preferably 10 wt% to 60 wt%, or more preferably 12 wt% to 60 wt%, or even more preferably 12 wt% to 45 wt%, or even more preferably 30 wt% to 45 wt%, or preferably 10 wt% to 12 wt%, or preferably 10 wt% to 30 wt%, or preferably 10 wt% to 45 wt%, or more preferably 12 wt% to 45 wt%, or even more preferably 12 wt% to 30 wt%, or even more preferably 30 wt% to 45 wt%, or even more preferably 30 wt% to 60 wt%, or preferably 45 wt% to 60 wt%.

[0029] Unless otherwise specified, the temperature and pressure conditions are room temperature (23°C) and standard pressure (101.3 kPa), also known as “ambient conditions.” Additionally, unless otherwise specified, all conditions include a relative humidity of 50% (RH).

[0030] All ranges listed are inclusive and composable. For example, a disclosure of 0.25 wt% to 0.5 wt%, or preferably 0.35 wt% to 0.45 wt%, will include all of 0.25 wt% to 0.5 wt%, or preferably 0.35 wt% to 0.45 wt%, or 0.25 wt% to 0.35 wt%, or 0.25 wt% to 0.45 wt%, or 0.35 wt% to 0.5 wt%, or 0.45 wt% to 0.5 wt%.

[0031] As used herein, the term "acrylic or vinyl" refers to addition polymerizable monomers or α,β-olefinically unsaturated monomers, such as alkyl and hydroxyalkyl (meth)acrylates, vinyl ethers, olefinically unsaturated carboxylic acids, alkyl (meth)acrylamides, or monomers containing oxidized olefinic groups, such as methoxy polyethylene glycol (meth)acrylate (mPEG(M)A) or poly(ethylene glycol) (meth)acrylate (PEG(M)A) and allyl polyethylene glycol (APEG).

[0032] As used herein, the term "aqueous" means that the continuous phase or medium is water and, based on the weight of the medium, comprises 0% to 10% by weight of the water-miscible compound. Preferably, "aqueous" refers to water.

[0033] As used herein, unless otherwise specified, the term "average number of oxidized olefin groups" refers to the number of oxidized olefin groups in any given acrylic or vinyl macromonomer having oxidized olefin groups, as specified in the literature of the manufacturer of the given macromonomer. Because this is an average number, the actual number of oxidized olefin groups represents the distribution within each batch of material; and the average number of oxidized olefin groups in a mixture of two or more such macromonomers will depend on the relative amount of each selected macromonomer having an oxidized olefin group to the total amount of macromonomers in the mixture. For example, in a 50:50 (mol / mol) mixture of alkoxy poly(ethylene glycol) (meth)acrylate having 10 ethylene glycol groups per oxidized olefin group and alkoxy poly(propylene glycol) (meth)acrylate having 6 propylene glycol groups per oxidized olefin group, the average number of oxidized olefin groups is 8 per side chain.

[0034] As used herein, the term "total weight based on monomers" refers to the amount of polymer or a portion thereof relative to the total weight of addition monomers (such as acrylic monomers) used to prepare the polymer.

[0035] As used herein, the term "dry blend" or "dry powder" refers to a storage-stable powder containing cement, cellulose ether, any other polymer additives, and any fillers, as well as drying additives. Dry blends do not contain water; therefore, they are storage-stable.

[0036] As used herein, the term "fluid" (or fluids) refers to a flowing composition of matter, regardless of its physical state or phase. Fluids may include suspensions, dispersions, solutions, fluidized solids or amorphous materials, aerosols, or gases.

[0037] As used herein, the term "side chain" group refers to a side chain of a polymer or a group covalently connected to the main chain of the polymer and not an end group.

[0038] As used herein, unless otherwise specified, the phrase “polymer” includes homopolymers and copolymers derived from two or more different monomers, as well as segmental and block copolymers.

[0039] As used herein, the term "storage stable" means that, for a given powdered additive composition, the powder will not clump, and for a given aqueous additive composition, when allowed to stand on a shelf at room temperature and standard pressure, the liquid composition will not become cloudy, separate, or precipitate after 5 days or preferably 10 days.

[0040] As used herein, the term “substantially free of organic solvents” means that the composition contains less than 0.5% by weight of any one or more organic solvents based on the total weight of the composition, or preferably contains no added organic solvents, or more preferably contains 1000 ppm or less of any one or more organic solvents.

[0041] As used herein, the phrase “total moles of carboxylic acid groups” refers to the number of moles of olefinically unsaturated carboxylic acid monomers used to prepare a given polymer, or, if not an addition polymer, the total number of moles of carboxylic acid groups in one or more polymeric polycarboxylic acids, as determined by aqueous titration of the given polymer with KOH to neutralize the composition to pH 7.0.

[0042] As used herein, the term "weight-average molecular weight" for brush polymers containing olefinic side chain groups refers to the average weight obtained by gel permeation chromatography (GPC) of the weight distribution determined using poly(acrylic acid) standards required to resolve the molecular weight of a given polymer.

[0043] As used herein, unless otherwise specified, the term "weight%" means a weight percentage based on the indicated denominator.

[0044] As used herein, the phrases “total solids,” “solids,” or “as solids” refer to the total amount of any or all non-volatile components or materials present in a given composition, including synthetic polymers, monomers, natural polymers, acids, defoamers, hydraulic cement, fillers, inorganic materials, and other non-volatile materials and additives, such as initiators. Water, ammonia, and volatile solvents are not considered solids.

[0045] According to the present invention, the method of polymerization in an aqueous medium comprises polymerizing monomers that form a solution in water. However, the polymer products of the method of the present invention behave similarly to two-phase polymerization, such as stable suspension or emulsion polymerization; and, furthermore, aqueous compositions containing brush copolymers, such as those prepared by these methods, behave like emulsions or stable suspensions. At a pH equal to or lower than the pKa of the olefinic unsaturated carboxylic acid in the aqueous monomer mixture or brush polymer composition of the present invention, an associative complex is formed between the protonated carboxylic acid group and the olefinic side chain of the brush polymer. Therefore, the present invention enables the polymerization of highly water-soluble acrylic or vinyl macromonomers containing olefinic chain groups at an acceptable high solids content while minimizing the energy and water consumption in the process. Examples of suitable macromonomers include methoxy poly(ethylene glycol) methacrylate (MPEGMA).

[0046] This invention achieves a significant reduction in viscosity during the polymerization of aqueous monomer mixtures, and a significant reduction in viscosity of aqueous brush polymer compositions containing olefinic side chain groups. For comparison, aqueous compositions of the same monomer mixture or its brush polymer are used, these compositions comprising individual macromonomers or macromonomers mixed with one or more monomers having a water solubility of less than 1% by weight in deionized (DI) water at 23°C and 101.3 kPa, such as alkyl (meth)acrylates, styrene, or vinyl ester monomers, such as methyl methacrylate (MMA). Polymerization according to the method of the invention results in an in-process viscosity of over 10% by weight of MPEGMA total polymer solids. 4 cP decreased to below 10 2 cP. Furthermore, in another example of the method of the present invention, an aqueous monomer mixture comprising 15% by weight of methacrylic acid (MAA) based on the total weight of monomers allows the viscosity to be increased from above 10% before, during, and after polymerization at 10% by weight of MPEGMA total monomer / polymer solids. 4 cP decreased to below 10 2 cP. In the comparative MPEGMA aqueous monomer mixture / brush polymer in the two examples above, 15% by weight of methyl methacrylate (MMA) was used.

[0047] Specifically, the inventors have discovered aqueous compositions of polymerizable aqueous monomer mixtures containing oxidized olefinic groups of acrylic or vinyl macromonomers and brush polymers of the same macromonomers in (co)polymerizable form, having more than one phase domain, resembling emulsions or suspensions. The aqueous compositions of brush polymers prepared from the aqueous monomer mixtures of the present invention behave in the same manner as the aqueous monomer mixtures used to prepare them. The aqueous brush polymer compositions according to the present invention comprise one or more fluids containing carboxylic acid groups, selected from polymerizable polycarboxylic acids such as polyacrylic acid or poly(methacrylic acid) (pMAA) or mixtures thereof, copolymerizable olefinic unsaturated carboxylic acids such as copolymerizable methacrylic acid (MAA), or combinations thereof. Additionally, the present invention provides methods for preparing aqueous brush polymer compositions, comprising polymerizing one or more acrylic or vinyl macromonomers containing oxidized olefinic groups in the presence of one or more fluids containing carboxylic acid groups selected from one or more polymerizable polycarboxylic acids or copolymerizable olefinic unsaturated carboxylic acids or combinations thereof.

[0048] The one or more acrylic or vinyl brush polymers containing oxidized olefin side chain groups according to the present invention may be selected from homopolymers of acrylic or vinyl macromonomers having oxidized olefin side chain groups, or copolymers of one or more macromonomers and one or more olefinically unsaturated carboxylic acid monomers. The aqueous compositions of the present invention may not contain polymerized polycarboxylic acids, wherein they comprise brush copolymers containing one or more olefinically unsaturated carboxylic acids in copolymer form.

[0049] The acrylic or vinyl brush polymers of the present invention may comprise any such polymer having an alkylene oxide side chain group, preferably a poly(ethylene glycol) group or an alkoxy poly(ethylene glycol) group. The alkylene oxide side chain group may be, for example, a poly(alkylene glycol) side chain terminated with a hydroxyl, methyl, ethyl, or any other nonionic group that is uncharged at the pH of the composition. The side chain may be an alkylene glycol (EO, PO, BO, etc.) or a mixture thereof. Suitable alkylene oxide side chain groups may be selected from poly(alkylene glycols), such as poly(ethylene glycol), poly(propylene glycol), poly(butanediol), or copolyethers of two or more thereof; alkoxy poly(alkylene glycols), such as methoxy poly(alkylene glycols), ethoxy poly(alkylene glycols), and combinations thereof. Preferably, the alkylene oxide side chain group in the vinyl or acrylic brush polymers of the present invention has 5 to 25, or more preferably 7 to 15, ether or alkylene glycol groups. More preferably, the ether group is an ethoxy (-CH2CH2O-) or (EO) group.

[0050] The backbone of the vinyl or acrylic brush polymers of the present invention may comprise repeating units of one or more olefinically unsaturated carboxylic acids (such as acrylic acid or methacrylic acid); however, the repeating units are not limited to these. The vinyl or acrylic brush polymers of the present invention may also be synthesized using any other unsaturated monomers, such as vinyl, allyl, or isoprene, in an amount of up to 10% by weight of monomer solids.

[0051] In the acrylic or vinyl macromonomers containing oxidized olefin chain groups and the acrylic or vinyl brush polymers containing oxidized olefin side chain groups of the present invention, the average number of oxidized olefin side chain groups in one or more macromonomers or in the brush polymers containing oxidized olefin side chain groups is in the range of 1.5 to 100 ether groups, for example, 2 or more, or 3 or more, or 1.5 to 50 ether groups, or preferably 2 to 40, or more preferably 3 to 40, or more preferably 5 to 25 ether groups, or even more preferably 7 to 15 ether groups. Preferably, the macromonomers used to prepare the brush polymers containing oxidized olefin side chain groups of the present invention have a total of 5 to 25 alkylene glycol or ether units in the oxidized olefin groups, such as 7 or more alkylene glycol or ether units, or up to 15 alkylene glycol or ether units.

[0052] Suitable acrylic or vinyl brush polymers containing oxidized olefin side chain groups can be polymers based on a total weight of 20% to 100% by weight, or preferably 30% to 100% by weight, or preferably 40% to 70% by weight, or preferably 50% by weight or more, or preferably up to 98% by weight, or more preferably 65% ​​to 100% by weight, such as 65% to 98% by weight, of one or more acrylic or vinyl macromonomers having oxidized olefin side chain groups. Preferably, the remaining monomers used to prepare the polymer are one or more olefinically unsaturated carboxylic acids.

[0053] Suitable acrylic or vinyl macromonomers used for polymerizing or preparing the brush polymers of the present invention can be any macromonomer having a poly(alkylene glycol) chain having a desired number of ether or alkylene glycol units. Preferably, the acrylic or vinyl macromonomers used for preparing the vinyl or acrylic brush polymers of the present invention are methacrylate monomers having oxidized olefinic groups, such as poly(ethylene glycol)(meth)acrylate; alkoxy poly(alkylene glycol)(meth)acrylate, such as C1 to C4 alkoxy poly(C2 to C4 alkylene glycol)(meth)acrylate; hydrophobic C 12 To C 25Alkoxy poly(alkylene glycol) (meth)acrylate; or mixtures thereof. More preferably, one or more acrylic or vinyl macromonomers having oxidized olefinic groups include poly(ethylene glycol) (meth)acrylate, methoxy poly(ethylene glycol) (meth)acrylate, or mixtures thereof.

[0054] Suitable acrylic or vinyl macromonomers may include poly(ethylene glycol)(meth)acrylates or their corresponding (meth)acrylamides having 2 to 50 ethylene glycol units, poly(propylene glycol)(meth)acrylates or their corresponding (meth)acrylamides having 2 to 50 propylene glycol units, and C... 12 To C 25 alkoxy poly(ethylene glycol) (meth)acrylates or their corresponding (meth)acrylamides, C464 having 2 to 50 propylene glycol units 12 To C 25Alkoxylated poly(propylene glycol) (meth)acrylates or their corresponding (meth)acrylamides; polybutanediol (meth)acrylates or their corresponding (meth)acrylamides having a total of 2 to 50 alkylene glycol units; poly(ethylene glycol)-poly(propylene glycol) (meth)acrylates or their corresponding (meth)acrylamides having a total of 2 to 50 alkylene glycol units; poly(ethylene glycol)-poly(butanediol) (meth)acrylates or their corresponding (meth)acrylamides having a total of 2 to 50 alkylene glycol units; poly(propylene glycol)-poly(butanediol) (meth)acrylates or their corresponding (meth)acrylamides having a total of 2 to 50 alkylene glycol units; and poly(propylene glycol)-poly(butanediol) (meth)acrylates or their corresponding (meth)acrylamides having a total of 2 to 50 alkylene glycol units. The following are examples of poly(ethylene glycol)-poly(propylene glycol)-poly(butanediol)(meth)acrylates or their corresponding (meth)acrylamides: methoxy-poly(ethylene glycol)(meth)acrylates or their corresponding (meth)acrylamides having 2 to 50 or preferably 5 to 25 ethylene glycol units; methoxy-poly(propylene glycol)(meth)acrylates or their corresponding (meth)acrylamides having 2 to 50 or preferably 5 to 25 propylene glycol units; methoxy-poly(butanediol)(meth)acrylates or their corresponding (meth)acrylamides having a total of 2 to 50 or preferably 5 to 25 alkylene glycol units; and methoxy-poly(butanediol) mono(meth)acrylates or their corresponding (meth)acrylamides having a total of 2 to 50 alkylene glycol units. (Methacrylamide), methoxylated poly(ethylene glycol)-poly(propylene glycol)(meth)acrylate or its corresponding (meth)acrylamide having a total of 2 to 50 alkylene glycol units, methoxylated poly(ethylene glycol)-poly(butanediol)(meth)acrylate or its corresponding (meth)acrylamide having a total of 2 to 50 alkylene glycol units, methoxylated poly(propylene glycol)-poly(butanediol)(meth)acrylate or its corresponding (meth)acrylamide having a total of 2 to 50 alkylene glycol units, methoxylated poly(ethylene glycol)-poly(propylene glycol)-poly(butanediol)(meth)acrylate or its corresponding (meth)acrylamide having a total of 2 to 50 alkylene glycol units, or having 2 to 50 or more alkylene glycol units. Ethoxylated poly(ethylene glycol) (meth)acrylates or their corresponding (meth)acrylamides having 5 to 25 ethylene glycol units; poly(ethylene glycol) (meth)allyl ethers or monovinyl ethers having 2 to 50 ethylene glycol units; poly(propylene glycol) (meth)allyl ethers or monovinyl ethers having 2 to 50 propylene glycol units; poly(ethylene glycol)-poly(propylene glycol) (meth)allyl ethers or monovinyl ethers having a total of 2 to 50 alkylene glycol units; poly(ethylene glycol)-poly(butanediol) (meth)allyl ethers or monovinyl ethers having a total of 2 to 50 alkylene glycol units; poly(propylene glycol)-poly(butanediol) (meth)allyl ethers or monovinyl ethers having a total of 2 to 50 alkylene glycol units.The methoxy poly(ethylene glycol) (methyl) allyl ether or monovinyl ether having 2 to 50 ethylene glycol units, the methoxy poly(propylene glycol) (methyl) allyl ether or monovinyl ether having 2 to 50 propylene glycol units, and the corresponding monoester, monoamide, diester and diamide of itaconic acid or maleic acid, or a mixture thereof.

[0055] More specifically, suitable acrylic or vinyl macromonomers having oxidized olefinic groups may include one or more of the following: poly(ethylene glycol). 4-40 (Meth)acrylates, such as polyethylene glycol. 4-40 (Meth)acrylates; Alkoxylated poly(alkylene glycols) 4-40 (Meth)acrylates, such as C1 to C4 alkoxy poly(C2 to C4 alkylene glycols). 4-40 (Meth)acrylates, C1 to C4 alkoxy poly(C2 to C4 alkylene glycols) 4-40 (Meth)acrylate alkoxy poly(ethylene glycol) 4-40 (meth)acrylates; or hydrophobic C 12 To C 25 Alkoxylated poly(alkylene glycol) 4-40 (Meth)acrylates, such as acrylic or vinyl macromonomers, preferably include C1 to C4 alkoxy poly(C2 to C4 alkylene glycols). 4-40 (Meth)acrylates and poly(ethylene glycol) 1.5-100 (Meth)acrylates, and more preferably, polyethylene glycol. 4-40 (Meth)acrylates and C1 to C4 alkoxy poly(ethylene glycol) 4-40 (Meth)acrylates, or even more preferably, methoxy poly(C2 to C4 alkylene glycols). 4-40 (Meth)acrylates and poly(ethylene glycol) 4-40 (Meth)acrylates.

[0056] Examples of suitable acrylic or vinyl brush polymers of the present invention are (co)polymers of acrylate or acrylamide macromonomers having oxidized olefinic groups, such as poly(ethylene glycol), with one or more olefinically unsaturated carboxylic acid monomers.

[0057] Suitable olefinically unsaturated carboxylic acids for preparing the aqueous brush polymers of the present invention containing olefinically oxidized side chain groups and carboxylic acid groups may include any one or more monomers containing carboxylic acid, such as methacrylic acid, acrylic acid, crotonic acid, fumaric acid, maleic acid, 2-methylmaleic acid, itaconic acid, citraconic acid, mesocarboxylic acid, 2-methylitaconic acid, cyclohexene dicarboxylic acid, α,β-methyleneglutaric acid, monoalkyl maleate and monoalkyl fumarate; olefinically unsaturated anhydrides, such as maleic anhydride, itaconic anhydride, citraconic anhydride, mesocarboxylic anhydride, acrylic anhydride and methacrylic anhydride.

[0058] Furthermore, the aqueous brush-like polymer composition according to the invention may comprise one or more comonomers in copolymer form, which have a water solubility of less than 1% by weight in deionized (DI) water at 23°C and 101.3 kPa pressure. Suitable comonomers may include any of the following: C1 to C 12 Alkyl (meth)acrylates, such as lower alkyl (C1-C8) alkyl (meth)acrylates, such as methyl methacrylate (MMA), ethyl acrylate (EA), and 2-ethylhexyl methacrylate (2-EHA); hydroxyalkyl (meth)acrylates, such as hydroxyethyl methacrylate; aryl groups, such as styrene; vinyl ester monomers; and mixtures thereof. Such comonomers may comprise up to 10% by weight of solids, or preferably up to 5% by weight, based on the total weight of the monomers used to prepare the brush polymer. In the case where the aqueous composition contains one or more polymeric polycarboxylic acids as one or more carboxylic acids, the amount of such comonomers may be higher, for example up to 80% by weight, or for example up to 40% by weight, based on the total weight of the monomers used to prepare the brush polymer.

[0059] The aqueous brush polymer containing olefin side chain groups of the present invention may be crosslinked, but preferably, is not crosslinked. Crosslinking can be achieved by methods such as including in an aqueous monomer mixture one or more diene-bonded unsaturated crosslinking agent monomers, such as (poly) glycol di(meth)acrylate, like (poly) glycol dimethacrylate or (poly) glycol diacrylate; allyl acrylate or allyl methacrylate; or combinations thereof.

[0060] Preferably, in order to ensure that the aqueous compositions of one or more brush polymers containing olefinic side chain groups of the present invention exhibit water retention rather than water reduction, such polymers comprise a polymeric product based on a total weight of less than 0.1% by weight or preferably less than 0.05% by weight of any salt-containing monomer (such as an olefinic unsaturated carboxylate monomer) used to prepare the brush polymer.

[0061] According to the aqueous composition of the present invention, a suitable brush polymer containing olefin side chain groups may have a weight-average molecular weight (relative to Mw) of 100,000 g / mol to 50,000,000 g / mol, or preferably 250,000 g / mol or greater, or more preferably 300,000 g / mol or greater, or preferably 20,000,000 g / mol or less, or more preferably 10,000,000 g / mol or less.

[0062] According to the polymerization method and aqueous composition of the present invention, one or more polymeric polycarboxylic acids may comprise any polymer or carboxylic acid-functionalized polymer (if not an addition polymer), such as poly(aspartic acid). The polymer comprises one or more monomers containing carboxylic acids in copolymer form, such as methacrylic acid, acrylic acid, crotonic acid, fumaric acid, maleic acid, 2-methylmaleic acid, itaconic acid, citraconic acid, mesoconic acid, 2-methylitacinic acid, cyclohexene dicarboxylic acid, α,β-methyleneglutaric acid, monoalkyl maleate, and monoalkyl fumaric acid; and olefinic unsaturated anhydrides, such as maleic anhydride, itaconic anhydride, citraconic anhydride, mesoconic anhydride, acrylic anhydride, and methacrylic anhydride. The amount of such monomers should provide an acid copolymer unit in an amount of 50% to 100% by weight, or preferably 80% by weight or greater, of all monomers used to prepare the polymer. In addition to the units containing acidic groups that copolymerize, the remaining portion of the polymerized polycarboxylic acid may contain hydroxyl-containing copolymer units, and optionally, additional olefinically unsaturated monomer copolymer units. Therefore, the copolymer and the copolymerized polycarboxylic acid may contain hydroxyl-containing olefinically unsaturated monomers as copolymer units, and optionally, additional olefinically unsaturated monomers as copolymer units.

[0063] In the method for preparing an aqueous composition of a brush polymer containing olefin side chain groups according to the invention, the polymerization comprises conventional aqueous addition polymerization. The polymerization can be carried out by conventional free radical addition polymerization in the presence of a thermal initiator or a redox initiator, or preferably a thermal initiator, such as aqueous emulsion polymerization in the presence of one or more persulfates or peracids. The polymerization can be carried out as a shot of aqueous monomer mixture added together or separately, or can include the gradual addition of one or more monomers to the aqueous monomer mixture in one or more stages, either together or separately. The polymerization can be carried out in an aqueous medium at a temperature of 40°C to 80°C, or more preferably 71°C or lower. Preferably, the method for preparing a brush polymer containing olefin side chain groups according to the invention comprises conventional free radical addition aqueous polymerization, such as shot polymerization in which the aqueous monomer mixture is added all at once to a reaction vessel.

[0064] More preferably, the polymerization of the brush polymer containing olefin side chain groups of the present invention is carried out in an aqueous medium having a thermal initiator at a temperature of 40°C to 75°C, or most preferably 71°C or lower. Most preferably, the polymerization of the brush polymer containing olefin side chain groups of the present invention is carried out in an aqueous medium having a thermal initiator having a concentration of 0.05% to 1% by weight, or even more preferably 0.2% by weight or less, based on the total weight of the monomers (monomer solids) used to prepare the polymer.

[0065] An aqueous composition of one or more brush polymers containing olefin side chain groups has a pH of 5 or lower, for example 1 to 5 or preferably 4.8 or lower, or for example 1 to 4.8.

[0066] An aqueous composition of one or more brush polymers containing olefinic side chain groups comprises less than 1% by weight of salt based on the total solid weight of the composition, or preferably does not contain added salt, except for salts that are part of a polymerization initiator or a polymerization byproduct thereof. If a salt is used, it is preferably a monovalent metal salt, such as a sodium or ammonium salt.

[0067] According to the aqueous polymerization method of the present invention, one or more polymeric polycarboxylic acids comprise polymers or copolymers of one or more olefinically unsaturated carboxylic acids in copolymer form. Suitable olefinically unsaturated carboxylic acids may include, for example, methacrylic acid, acrylic acid, crotonic acid, fumaric acid, maleic acid, 2-methylmaleic acid, itaconic acid, citraconic acid, mesoconic acid, 2-methylitacinic acid, cyclohexene dicarboxylic acid, α,β-methyleneglutaric acid, monoalkyl maleate, and monoalkyl fumarate; olefinically unsaturated anhydrides, such as maleic anhydride, itaconic anhydride, citraconic anhydride, mesoconic anhydride, acrylic anhydride, and methacrylic anhydride. Preferably, the olefinically unsaturated carboxylic acid is acrylic acid or methacrylic acid. Such monomers should be used in the copolymer or copolymeric polycarboxylic acid in an amount providing 65% to 100% by weight, preferably 80% to 100% by weight, of the monomers used to prepare the polymeric polycarboxylic acid. The remainder of one or more polymeric polycarboxylic acids (besides the copolymerized acidic unit) may comprise copolymerized hydroxyl or amide groups, hydroxyl-containing olefinic unsaturated monomers (such as hydroxyethyl methacrylate), and amide-containing monomers (such as (meth)acrylamide). Polymeric polycarboxylic acids can be prepared by conventional aqueous addition polymerization, such as in the presence of one or more initiators.

[0068] According to the method and aqueous composition of the present invention, the polymeric polycarboxylic acid contains a carboxylate of less than 1% by weight based on the total weight of the monomers used to prepare the polymeric polycarboxylic acid, or preferably, does not contain a salt.

[0069] The one or more aromatic cofactors of the present invention can be any compound, polymer, or oligomer having one or more and up to 1,000,000, or up to 100,000, or preferably two or more, or more preferably three or more aromatic groups or phenolic groups (such as phenolic or naphthol groups), wherein when the aromatic cofactor has aromatic groups other than phenolic groups, it further contains at least one sulfate group. Preferably, the aromatic cofactors of the present invention have one or more aromatic groups and at least one sulfate group, or more preferably, two or more such combinations. Cofactors may include β-naphthalenesulfonate (BNS) resins, styrene sulfonate (co)polymers and lignin sulfonates, as well as phenolic resins and tannins. Aromatic cofactors may include, for example, poly(naphthalenesulfonate) formaldehyde condensate resins or polymers, such as β-naphthalenesulfonate formaldehyde condensate polymers or β-naphthalenesulfonate resins (BNS), poly(styrene-co-styrenesulfonate) copolymers, catechol tannins, phenolic resins such as phenol-formaldehyde resins, polyphenols, naphthols such as 2-naphthol, and mixtures thereof. Preferably, the aromatic cofactor is branched, and more preferably, it is BNS.

[0070] The aromatic cofactor of the present invention has one or more aromatic or phenolic groups on repeating units of oligomers or polymers in 10% to 100%, or preferably 30% to 100%, or more preferably 50% to 100% or 60% to 100% of their repeating units. For example, phenol-formaldehyde resin or naphthalene sulfonate aldehyde resin are each considered as homopolymers or oligomers having phenolic or aromatic groups in 100% of their repeating units, respectively. Preferably, in oligomers or polymers having a combination of aromatic and sulfate groups, more than 30% by weight or preferably more than 50% by weight of aromatic groups are accompanied by sulfate groups, such as poly(styrene-co-styrene sulfonate) copolymers, which are copolymers based on styrene sulfonates with a total molar percentage of vinyl monomers used to prepare the copolymer of more than 30 mol%.

[0071] Aromatic cofactors can be linear, such as in polymers containing styrene sulfonates, and are preferably branched, such as in any condensation resin, such as naphthalene sulfonate aldehydes or phenolic condensates, tannins, or lignin sulfonates. When the cofactor is linear, it preferably has a molecular weight of 600,000 to 10,000,000.

[0072] Suitable examples of aromatic cofactors are commercially available, including MELCRETE. TM 500 powder (BASF, Ludwigshafen, DE) and its liquid form MELCRETE TM 500L liquid (BASF). Both are BNS polymers or oligomers. MELCRETE TMPolymer 500 is a sulfonated naphthalene condensate with formaldehyde.

[0073] The compositions of the present invention can be used in wet (aqueous) or dry powder form. The wet aqueous compositions are used with wet cement, and the dry powder is used with dry cement. The aromatic cofactors of the present invention can be used in wet or dry form and can be combined (wet or dry) with brush polymers containing olefin side chain groups to prepare additive compositions. Drying to form a dry powder composition can be carried out by spray drying of any polymer or cofactor or both of the aqueous composition prior to mixing with cement powder, or preferably by heating in a vacuum oven, or by an azeotropic method as described in the prior art.

[0074] In the compositions of the present invention, a brush polymer containing olefinic side chain groups and one or more aromatic cofactors may be combined such that, in use, the ratio of the total weight of the brush polymer to the total weight of the cement admixture (in solids) is in the range of 0.05% to 2% by weight, or preferably, 0.1% to 1% by weight.

[0075] The aqueous compositions of the present invention can be used by mixing them with hydraulic binders or cement and water to prepare concrete or cement admixtures, or by drying them and mixing them with dry cement followed by water before use. The compositions of the present invention can be mixed with hydraulic cement in any manner, provided that no aromatic cofactors and any polycarboxylic acid ether copolymer water-reducing agents (if used) are added to the wet cement before the brush polymer containing olefin side chain groups is added. Preferably, the compositions of the present invention comprise a single aqueous composition added to wet concrete or cement.

[0076] When the composition of the present invention further comprises hydraulic or wet-curing inorganic cement, the total amount of one or more brushable polymers (based on solids) is in the range of 0.05% to 2% by weight, or preferably 0.1% to 1% by weight, or more preferably 0.2% to 0.5% by weight, based on total cement solids. Furthermore, the composition may contain one or more aromatic cofactors (based on solids) in the range of 0.1% to 10% by weight, or preferably 0.2% to 5% by weight, or more preferably 0.2% to 2% by weight, based on total cement solids.

[0077] The aqueous composition or dry powder of the present invention may also contain cellulose ethers, such as HPMC and / or HEMC (hydroxyethyl methyl cellulose), or water-reducing agents, such as polycarboxylate ethers. The total amount of any polycarboxylate ether copolymer water-reducing agent in the composition may be in the range of 0.1% to 10% by weight, or preferably 0.2% to 5% by weight, of the total cement solids content of the cement admixture.

[0078] Furthermore, the compositions of the present invention may contain conventional additives in wet or dry form, such as cement curing accelerators and retarders, air entrainers or defoamers, shrinkage agents and wetting agents; surfactants, especially nonionic surfactants; spreading agents; mineral oil dust suppressants; biocides; plasticizers; organosilanes; antifoaming agents, such as poly(dimethylpolysiloxane) (PDMS) and emulsified PDMS, silicone oils and ethoxylated nonionic compounds; and coupling agents, such as epoxysilanes, vinylsilanes and hydrophobic silanes. Example

[0079] The following examples illustrate the invention. Unless otherwise specified, all parts and percentages are by weight, all temperatures are in °C, and all preparation and testing procedures were performed at room temperature (23 °C) and pressure (1 atm). In the examples below and in Tables 1, 2, and 3, the following abbreviations are used: RDP: redispersible polymer powder; MPEGMA: methoxy poly(ethylene glycol) methacrylate; MAA: methacrylic acid; AA: acrylic acid; MMA: methyl methacrylate; EO: ethylene oxide.

[0080] All chemicals except AA, MMA, and MAA were purchased from Sigma-Aldrich and used without further purification.

[0081] Synthesis Example 1: Polymerization of Polycarboxylic Acids A 50 wt% solids poly(acrylic acid) additive was synthesized in a 1 L round-bottom flask. 103.5 g of water was added, and the mixture was stirred at 170 rpm and heated to 73 °C under a nitrogen atmosphere. Then, 1.25 g of a 0.15 wt% ferrous(II) sulfate solution dissolved in 5.94 g of water and 2.83 g of sodium metabisulfite were added. Next, 40.76 g of sodium metabisulfite dissolved in 63.31 g of water, 150 g of AA rinsed with 3.5 g of water, and 0.57 g of sodium persulfate dissolved in 8.5 g of water were simultaneously fed over 70, 90, and 95 minutes, respectively. The temperature was gradually increased to 75 °C and maintained at 75 °C for an additional 15 minutes after the sodium persulfate solution feeding was completed. After this maintenance, 0.21 g of sodium persulfate dissolved in 10.0 g of water was added over 10 minutes, and the reactor was then maintained at 75 °C for another 20 minutes. After cooling to 60°C, 4.8 g of 35% hydrogen peroxide was added over 2 minutes, and the reactor was then kept at 60°C for another 10 minutes. Finally, the reactor was cooled to room temperature.

[0082] Synthesis Example 2: Brush polymer composition containing olefin side chain groups and individual polymeric polycarboxylic acidsThe brush polymers of Comparative Example 1 and Inventive Examples 1, 2, and 3 were synthesized in a 300 mL flat-bottomed flask and stirred with an impeller at 120 rpm. 12.8 g of MPEGMA-500 (averaging 9 EO units and a molar mass of 500 g), 2.2 g of MMA, water, and a 50 wt% polyacrylic acid solution from Synthetic Example 1 were added to a reactor. The solution was heated to 70°C under nitrogen for 1 hour. Then, a solution of 0.030 g of ammonium persulfate in 1.875 g of water was added, followed by rinsing with another 1.875 g of water. The temperature was maintained at 70°C for 2 hours, and then another 0.030 g of ammonium persulfate in 1.875 g of water was added, followed by rinsing with another 1.875 g of water. The temperature was again maintained at 70°C for 2 hours, and then cooled to room temperature. The composition and polymerized polycarboxylic acid of this Synthetic Example 2 are given in Table 1 below.

[0083] Synthesis Example 3: Brush polymer composition containing olefinic side chain groups and carboxylic acids in copolymer form The brush-like polymer of Example 4 was synthesized in a 1L round-bottom flask. 451.1 g of water, 21.3 g of MPEGMA-500, and 3.7 g of MAA were added to the reactor, and each monomer was rinsed with an additional 6.2 g of water. The solution was heated to 70°C under nitrogen for 1 hour. Next, a solution of 0.050 g of ammonium persulfate in 3.124 g of water was added, and the solution was rinsed with another 3.124 g of water. The temperature was maintained at 70°C for 2 hours, and then another solution of 0.050 g of ammonium persulfate in 3.124 g of water was added, and the solution was rinsed with another 3.124 g of water. The temperature was again maintained at 70°C for 2 hours, and then cooled to room temperature. The composition prepared by this synthetic Example 3 is given in Table 3 below.

[0084] The brush-like polymer of Example 5 was synthesized in a 1L round-bottom flask. 401.6 g of water, 42.5 g of MPEGMA-500, and 7.5 g of MAA were added to the reactor, and each monomer was rinsed with an additional 12.5 g of water. The solution was heated to 70°C under nitrogen for 1 hour. Next, a solution of 0.100 g of ammonium persulfate in 6.249 g of water was added, followed by rinsing with another 6.249 g of water. The temperature was maintained at 70°C for 2 hours, and then another solution of 0.100 g of ammonium persulfate in 6.249 g of water was added, followed by rinsing with another 6.249 g of water. The temperature was again maintained at 70°C for 2 hours, and then cooled to room temperature. The composition prepared by this synthetic Example 3 is given in Table 3 below.

[0085] Table 1: Compositions from Synthetic Example 1 prepared using poly(acrylic acid) additives

[0086]

[0087] * indicates a comparison example.

[0088] Test method: Use the following testing methods:

[0089] Solid content The solids content was measured by weighing an indicated amount of the given composition and then evaporating the water in an oven at 60°C. The solids content of the indicated examples is listed in Tables 2 and 3 below.

[0090] Solution viscosity: The solution viscosity was measured using a Brookfield viscometer with the indicated rotor at the indicated frequencies of 10 rpm and 30 rpm. The solution viscosity results for the indicated examples are given in Tables 2 and 3 below.

[0091] Table 2: Brinell viscosity data of examples prepared using poly(acrylic) polymers

[0092]

[0093] * indicates a comparison example.

[0094] Table 3: Brookfield viscosity data for examples with methacrylic acid as a comonomer.

[0095]

[0096]

[0097] * indicates a comparison example.

[0098] As shown in Table 2 above, the inventive examples prepared in the presence of polyacrylic acid contained 10% by weight of MPEGMA copolymer solids, but produced a much lower viscosity than the comparative examples. This viscosity reduction was proportional to the amount of poly(acrylic acid) added. It is important to note that all examples and comparative examples had the same MPEGMA copolymer content. However, the overall solids content increased with the amount of poly(acrylic acid) added; despite this, the measured viscosity decreased with the amount of poly(acrylic acid) added. Finally, Table 3 above lists the viscosities of inventive examples 4 and 5, which comprise an acrylic brush polymer containing olefinic side chain groups and MAA in copolymer form as a comonomer. Even at the same solids content as Comparative Example 1, the compositions of Examples 4 and 5 exhibited a significantly reduced viscosity.

Claims

1. An aqueous composition used as a thickener and water-retaining agent, comprising: an aqueous medium; One or more brush polymers containing oxidized olefin side chain groups, comprising copolymers of one or more acrylic or vinyl macromonomers in copolymer form with one or more olefinically unsaturated carboxylic acids; One or more aromatic cofactors; and One or more fluids containing carboxylic acid groups, wherein: A mixture of olefinically unsaturated carboxylic acids and polymeric polycarboxylic acids in copolymer form, which are part of the brush-like polymer containing olefinic side chain groups. The aqueous medium is at least 90% by weight water; The composition has a pH of 1 to 5 and a solids content in the range of 8% to 60% by weight; and The one or more acrylic or vinyl macromonomers mentioned herein include C1 to C4 alkoxy poly(C2 to C4 alkylene glycol) (meth) acrylates.

2. The aqueous composition according to claim 1, having a pH of 1 to 4.8, and further wherein the composition is substantially free of salt or contains no added salt, except for any one or more initiators or their polymerization byproducts.

3. The aqueous composition according to claim 1, comprising the following molar ratio: The ratio of the total molar number of carboxylic acids to the total molar number of olefin oxides is in the range of 0.1:1 to 10:

1. The total molar number of carboxylic acids is determined as the total molar number of olefinically unsaturated carboxylic acid monomers used to prepare the one or more brush polymers containing olefin oxide side chain groups, plus the total molar number of olefinically unsaturated carboxylic acid monomers used to prepare the one or more polymeric polycarboxylic acids, and, if any polymeric polycarboxylic acid is not an addition polymer, the total molar number of carboxylic acid groups in the one or more polymeric polycarboxylic acids. The total molar number of olefin oxides is determined as the total molar number of the one or more acrylic or vinyl macromonomers containing olefin oxide side chain groups used to prepare the one or more brush polymers containing olefin oxide side chain groups, multiplied by the average number of olefin oxide chain groups in the total amount of acrylic or vinyl macromonomers containing olefin oxide chain groups, as reported by the macromonomer manufacturer.

4. The aqueous composition according to claim 3, wherein the molar ratio of the total molar number of carboxylic acids to the total molar number of olefin oxides is in the range of 0.2:1 to 5:

1.

5. The aqueous composition according to claim 1, comprising a storage-stable aqueous mixture or additive concentrate with a solid content ranging from 10% to 40% by weight.

6. A method for preparing an aqueous composition, comprising: In the presence of one or more initiators, at a pH of 1 to 5, an aqueous medium and a mixture of one or more aqueous monomers containing oxidized olefinic groups of acrylic or vinyl macromonomers are polymerized in the presence of a fluid containing carboxylic acid groups, which is a mixture of copolymerizable olefinically unsaturated carboxylic acids and polymerizable polycarboxylic acids, to form a brush polymer containing oxidized olefinic side chain groups, wherein the brush polymer containing oxidized olefinic side chain groups comprises a copolymer of C1 to C4 alkoxy poly(C2 to C4 alkylene glycol) (meth)acrylate in copolymer form with one or more olefinically unsaturated carboxylic acids. The aqueous portion of the aqueous monomer mixture comprises at least 90% by weight water, and furthermore, the polymerization is carried out at a solids content in the range of 8% to 60% by weight; and The one or more acrylic or vinyl macromonomers mentioned herein include C1 to C4 alkoxy poly(C2 to C4 alkylene glycol) (meth) acrylates.

7. The method according to claim 6, wherein, In the polymerization, the aqueous monomer mixture has a pH of 1 to 4.8; and, In addition, the aqueous monomer mixture contains essentially no salt or no added salt, except for any one or more initiators.

8. The method according to claim 6, wherein in the polymerization of the aqueous monomer mixture, the molar ratio is: The total molar number of carboxylic acids is determined as the total molar number of olefinically unsaturated carboxylic acid monomers used in the polymerization of the one or more macromonomers containing oxidized olefinic groups, plus the total molar number of olefinically unsaturated carboxylic acid monomers used to prepare the one or more polymeric polycarboxylic acids, and, if any polymeric polycarboxylic acid is not an addition polymer, the total molar number of carboxylic acid groups in the one or more polymeric polycarboxylic acids. The total molar ratio of olefin oxides is determined as the total molar ratio of acrylic or vinyl macromonomer polymers containing olefin oxide side chain groups used to prepare one or more brush polymers containing olefin oxide side chain groups, multiplied by the average number of olefin oxide chain groups in the total amount of acrylic or vinyl macromonomers containing olefin oxide chain groups, in the range of 0.1:1 to 10:1, as reported by the macromonomer manufacturer.

9. The method of claim 6, wherein the total amount of the acrylic or vinyl macromonomer containing oxidized olefinic groups is in the range of 20% to 100% by weight based on the total weight of the monomers used to prepare the brush polymer containing oxidized olefinic side chain groups.

10. The method of claim 6, wherein the polymerization is carried out at a solids content of 10% to 45% by weight.

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