Abstract: The present invention discloses a polycarboxylic acid water-reducing agent with high adaptability to temperature and a 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.

Abstract: Disclosed is a preparation method of a polycarboxylate water reducer having a regular sequence structure. The preparation method of the present invention comprises: performing Michael addition on polyethylene glycol ether acrylate macromonomer A and amino-containing carboxylic acid B for 5-12 hours, then cooling to 0° C., dropwise adding acryloyl chloride slowly and evenly, and further reacting for 12 hours at room temperature to obtain carboxyl-containing polyether macromonomer C; mixing the carboxyl-containing polyether macromonomer C, a small molecular RAFT reagent, an initiator, and water adequately; and holding the polymerization mass concentration at 30%-60% and heating to 60-80° C. in the atmosphere of N2 to react for 2-5 hours to obtain the polycarboxylate water reducer having a regular sequence structure.

Abstract: Disclosed is a preparation method of a polycarboxylate water reducer having a regular sequence structure. The preparation method of the present invention comprises: performing Michael addition on polyethylene glycol ether acrylate macromonomer A and amino-containing carboxylic acid B for 5-12 hours, then cooling to 0° C., dropwise adding acryloyl chloride slowly and evenly, and further reacting for 12 hours at room temperature to obtain carboxyl-containing polyether macromonomer C; mixing the carboxyl-containing polyether macromonomer C, a small molecular RAFT reagent, an initiator, and water adequately; and holding the polymerization mass concentration at 30%-60% and heating to 60-80° C. in the atmosphere of N2 to react for 2-5 hours to obtain the polycarboxylate water reducer having a regular sequence structure.

Abstract: The present invention provides a method for preparing a polymer and a use of the polymer. The resulting polymer is used as a dispersant for an aqueous dispersion of a hydraulic binder and/or a latent hydraulic binder, such that water-reducing rate is improved, and suitable control of air content can be achieved, thereby improving the strength of concrete. The method for preparing a polymer includes polycondensation of a polyether macromonomer A of a specific structure, a monomer B and an aldehyde C to obtain the polymer. The monomer B is phenylsulfonic acid, p-/o-aminophenylsulfonic acid, p-/o-hydroxylbenzoic acid, p-/o-aminobenzoic acid, p-/o-hydroxylphenylsulfonic acid, or a phosphoric acid group or phosphorous acid group-containing monomer of a specific structure. A molar ratio of the polyether macromonomer A and the monomer B is 1:(0.5 to 12).

Abstract: A slump retaining polycarboxylic acid superplasticizer. A weight average molecular weight of the superplasticizer is 20,000-80,000. The slump retaining polycarboxylic acid superplasticizer is prepared by performing polymerization reaction on a monomer A, a monomer B, a monomer C and a monomer D in an aqueous solution in the presence of a redox initiator, wherein a molar ratio of (the monomer A+the monomer B):the monomer C:the monomer D is 1:(3-8):(4-12), and a molar ratio of the monomer A to the monomer B is 1:(1-4).