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.

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.

The present invention discloses a polycarboxylic acid water-reducing agent with high adaptability to temperature and a preparation method for preparing the same. The polycarboxylic acid water-reducing agent is prepared by introducing an unsaturated macromonomer D with a temperature-sensitive side chain which could be bonded to the backbone of the polycarboxylic acid through free radical polymerization. The polycarboxylic acid water-reducing agent prepared by the invention has an adsorption group density that can be automatically adjusted with the change of ambient temperature, and thereby shows similar dispersing capability and dispersion retention capability at different ambient temperatures, demonstrating high adaptability to different ambient temperatures. It can be used in a larger temperature range with a constant dosage, which is beneficial to further popularization and application of the polycarboxylic acid water-reducing agent in regions of different climates.

Methods for the treatment of non-hardened cement compositions, especially returned concrete, and admixtures suitable to be used in such methods. The admixtures include modified starch and a sugar. Also, solid granules obtained by the methods and fresh concrete or mortar utilizing solid granules thus obtained.

A polymer having a dispersing function, a preparation method therefor, and a use thereof as a cement dispersant are provided. The polymer has a structural unit a, a structural unit b, a structural unit c and a structural unit d. The structural unit a is provided by an unsaturated polyether and/or polyester, the structural unit b is provided by an unsaturated carboxylic acid or an anhydride or salt thereof, the structural unit c is provided by a silane and/or siloxane containing a polymerizable group, and the structural unit d is provided by an unsaturated sulfonic acid or a salt thereof. The molar ratio of the structural unit a to the structural unit d is 1:(5-15) and the polymer has a weight average molecular weight of 20,000 to 120,000. The polymer can be used as an oil well cement dispersant.

A polymer having a dispersing function, a preparation method therefor, and a use thereof as a cement dispersant are provided. The polymer has a structural unit a, a structural unit b, a structural unit c and a structural unit d. The structural unit a is provided by an unsaturated polyether and/or polyester, the structural unit b is provided by an unsaturated carboxylic acid or an anhydride or salt thereof, the structural unit c is provided by a silane and/or siloxane containing a polymerizable group, and the structural unit d is provided by an unsaturated sulfonic acid or a salt thereof. The molar ratio of the structural unit a to the structural unit d is 1:(5-15) and the polymer has a weight average molecular weight of 20,000 to 120,000. The polymer can be used as an oil well cement dispersant.

Providing a multi-functional group superplasticizer for an ultra-high performance concrete and a method for preparing the same. Its backbone is an alkyl chain, and its side chain are some side chains with carboxylic acid or carboxylate at terminals, some polyether side chains, and some polyol amine side chains substituted with phosphoric acid or phosphite at terminals, the polyol amine side chains substituted with phosphoric acid or phosphite at terminals is connected to the backbone through a phenyl or an alkyl group of 1-9 carbons, and a ratio of a number of the side chains with carboxylic acid or carboxylate at terminals to a total number of side chains is ≥0 and ≤0.8; and a ratio of a number of the polyether side chains to the total number of side chains is ≥0.1 and ≤0.9.

The present invention relates to an additive for hydraulically setting compositions comprising a colloidally disperse preparation comprising at least one salt of a polyvalent metal cation with at least one organic phosphonate and/or phosphate compound as anion and at least one polymeric dispersant comprising anionic and/or anionogenic groups and polyether side chains. The additive is especially suitable as slump retainer and for improving early strength.

Disclosed are a multifunctional cement hydration heat control material and a manufacturing method therefor. The cement hydration heat control material in is a comb polymer having three side chain structures, the three side chain structures are respectively a carboxyl group, a sugar alcohol group, and a polyether structure, and the main chain of the polymer is a carbon chain structure formed by free-radical polymerization of a double bond in a double bond compound monomer. The multifunctional cement hydration heat control material can achieve integration of cement hydration heat control performance, water reduction performance, and shrinkage reduction performance in a same molecule, can achieve control focusing on a performance by means of structural adjustment, does not need multi-component compounding during use, and is more convenient. The control material is non-toxic and water-soluble, can be made to have an appropriate concentration, and is convenient to use.

Disclosed are a multifunctional cement hydration heat control material and a manufacturing method therefor. The cement hydration heat control material in is a comb polymer having three side chain structures, the three side chain structures are respectively a carboxyl group, a sugar alcohol group, and a polyether structure, and the main chain of the polymer is a carbon chain structure formed by free-radical polymerization of a double bond in a double bond compound monomer. The multifunctional cement hydration heat control material can achieve integration of cement hydration heat control performance, water reduction performance, and shrinkage reduction performance in a same molecule, can achieve control focusing on a performance by means of structural adjustment, does not need multi-component compounding during use, and is more convenient. The control material is non-toxic and water-soluble, can be made to have an appropriate concentration, and is convenient to use.