A copolymer may be obtained by polymerization reaction(s) using an anionic monomer and two polyethoxylated monomers. Such copolymers may have a polydispersity index, determined by size exclusion chromatography (SEC), of less than 3, and be obtained by at least one radical polymerisation reaction in water at a temperature ranging from 10 to 90° C. A composition may include such copolymers. Such copolymers may be prepared and use as a superplasticizer for a hydraulic binder composition.

A method includes adding (i) a comb polymer and (ii) a plasticizer to a mineral binder composition comprising swellable clays. The comb polymer includes: at least one poly(alkylene oxide) side chain-bearing monomer unit without ionic groups, optionally at least one cationic monomer unit, optionally at least one anionic monomer unit, and optionally, at least one non-ionic monomer unit, wherein a molar ratio of the cationic monomer units to the side chain-bearing monomer units is equal to or less than 10, a molar ratio of the anionic monomer units to the side chain-bearing monomer units is less than 1, and a molar ratio of the non-ionic monomer units to the side chain-bearing monomer units is less than 5.

A comb polymer, in particular for use as a clay-inerting agent, including: a) at least one poly(alkylene oxide) side chain-bearing monomer unit M1 without ionic groups, b) optionally at least one cationic monomer unit MC, c) optionally at least one anionic monomer unit MA, d) optionally, at least one non-ionic monomer unit M3, wherein the molar ratio of the cationic monomer units MC to the side chain-bearing monomer units M1 is equal to or less than 10, the molar ratio of the anionic monomer units MA to the side chain-bearing monomer units M1 is less than 1, preferably equal to or less than 0.5, and the molar ratio of the non-ionic monomer units M3 to the side chain-bearing monomer units M1 is less than 5.

An amphoteric betaine-type polycarboxylic acid water reducer and a preparation method therefor are provided in the present invention. An unsaturated betaine-type monomer A and an acrylic acid-type polyethylene glycol monomer B are placed in a reaction container, stirred until uniform and then an acrylic acid-type monomer C is added, the stirring is continued and water is added to make adjustments so as to make the total mass of the monomers account for 10%-20% of the total mass of the aqueous solution; and under the protection of an inert gas, the temperature is raised to 60° C.-100° C., an aqueous initiator solution is added, maintaining the temperature and reacting for 4-6 h, and after the reaction is completed, the solution is cooled to room temperature, and the pH value thereof is adjusted to 5-7 to prepare the amphoteric betaine-type polycarboxylic acid water reducer.

An amphoteric betaine-type polycarboxylic acid water reducer and a preparation method therefor are provided in the present invention. An unsaturated betaine-type monomer A and an acrylic acid-type polyethylene glycol monomer B are placed in a reaction container, stirred until uniform and then an acrylic acid-type monomer C is added, the stirring is continued and water is added to make adjustments so as to make the total mass of the monomers account for 10%-20% of the total mass of the aqueous solution; and under the protection of an inert gas, the temperature is raised to 60° C.-100° C., an aqueous initiator solution is added, maintaining the temperature and reacting for 4-6 h, and after the reaction is completed, the solution is cooled to room temperature, and the pH value thereof is adjusted to 5-7 to prepare the amphoteric betaine-type polycarboxylic acid water reducer.

The invention relates to a polymer which is obtainable by copolymerizing monomers comprising at least one ethylenically unsaturated monomer which comprises at least one acid group and at least one ethylenically unsaturated monomer (II) having polyether groups with 5 to 35 repeating units and at least one ethylenically unsaturated monomer (III) having polyether groups with 45 to 150 repeating units, the molar ratio of monomer (II) to monomer (III) being between 75:25 and 99.5:0.5. Further disclosed are the use of the polymer of the invention as an admixture for inorganic binder compositions, and a composition in powder form comprising an inorganic binder and the polymer of the invention.

The invention relates to a polymer which is obtainable by copolymerizing monomers comprising at least one ethylenically unsaturated monomer which comprises at least one acid group and at least one ethylenically unsaturated monomer (II) having polyether groups with 5 to 35 repeating units and at least one ethylenically unsaturated monomer (III) having polyether groups with 45 to 150 repeating units, the molar ratio of monomer (II) to monomer (III) being between 75:25 and 99.5:0.5. Further disclosed are the use of the polymer of the invention as an admixture for inorganic binder compositions, and a composition in powder form comprising an inorganic binder and the polymer of the invention.

Methods for plasticizing cementitious mixtures having relatively high water/cement ratio (at least 0.40 or higher) are surprisingly improved in terms of dosage efficiency, compared to conventional “superplasticizer” polycarboxylate polymers, when the comb-type carboxylate copolymer is formed from two different polyether side chains, specifically selected monomer constituents: (A) first polyoxyalkylene monomer represented by structural formula (R.sup.1)(R.sup.3)C═C(R.sup.2)((CH.sub.2).sub.m(CO).sub.nO(CH.sub.2).sub.o(AO).sub.pR.sup.4) wherein (AO).sub.p represents linear alkylene oxide and p is an integer of 5-23; (B) second polyoxyalkylene monomer represented by structural formula (R.sup.1)(R.sup.3)C═C(R.sup.2)((CH.sub.2).sub.m(CO).sub.nO(CH.sub.2).sub.o(AO).sub.qR.sup.4) wherein (AO).sub.q represents linear alkylene oxide groups and q is an integer of 20 to 200; (C) unsaturated carboxylic acid monomer represented by (R.sup.5)(R.sup.7)C═C(R.sup.6)(C(O)OM) wherein M represents an alkali metal, and the ratio of component A to component B is 20:80 to 50:50; and, optionally, (D) a water-soluble monomer represented by (R.sup.8)(R.sup.9)C═C(R.sup.10)(X) wherein R.sup.8, R.sup.9, and R.sup.10 each represent hydrogen or methyl group, and X represents C(O)NH.sub.2, C(O)NHR.sup.11, C(O)NR.sup.12R.sup.13, OR.sup.14, SO.sub.3H, C.sub.6H.sub.4SO.sub.3H, or C(O)NHC(CH.sub.3).sub.2CH.sub.2SO.sub.3H, or mixture thereof, wherein R.sup.11, R.sup.12, R.sup.13, and R.sup.14 each represent a C.sub.1 to C.sub.5 alkyl group.

An aqueous suspension including 5 to 65 wt. % of calcium hydroxide, wherein at least 50 wt. % of the calcium hydroxide is present in the form of nanoparticles, and at least one compound for stabilizing the suspension. The aqueous suspension accelerates the setting of mineral binder compositions without adversely affecting the processing properties of the composition.

An aqueous suspension including 5 to 65 wt. % of calcium hydroxide, wherein at least 50 wt. % of the calcium hydroxide is present in the form of nanoparticles, and at least one compound for stabilizing the suspension. The aqueous suspension accelerates the setting of mineral binder compositions without adversely affecting the processing properties of the composition.