A kind of preparation method of temperature-responsive comb structure polycarboxylic acid

Abstract

The invention relates to a preparation method of a temperature responsive comb-like structured polycarboxylic acid. By using acrylic ester, a temperature responsive monomer and the like as raw materials, a polycarboxylic acid material is prepared through steps of autopolymerization, graft copolymerization and hydrolysis. The preparation method comprises the following specific steps: acrylic ester,which is used as a reaction monomer, undergoes polymerization under the action of an initiator and a chain transfer agent to generate polyacrylate with controlled molecular weight; then, polyacrylateand the temperature responsive monomer are subjected to graft copolymerization to obtain a graft copolymer with the acrylic polymer as the a main chain and the temperature responsive polymer as a side chain; and finally, the graft copolymer undergoes hydrolysis to prepare the comb-like structured polycarboxylic acid with polyacrylic acid as the main chain and the temperature responsive polymer asthe side chain. By main chain polymerization before side chain grafting, polycarboxylic acid with the intelligent responsive side chain is successfully designed and synthesized. The reaction processis convenient and controllable, and is energy-saving and environmentally friendly. The product shows excellent temperature responsive behavior and multi-effects of inhibiting shrinkage of cement mortar, and has good market prospects and application value.

Description

technical field

[0001] The invention relates to the technical field of a temperature-responsive polycarboxylic acid for cement concrete, in particular to a comb-shaped polycarboxylic acid material synthesized by self-polymerization of an acrylic ester monomer and then grafted with a temperature-responsive monomer, followed by hydrolysis specific preparation method. Background technique

[0002] The rapid development of high-performance concrete has led to higher and higher requirements for the mechanical strength and durability of concrete, and the shrinkage and cracking of concrete has always been one of the problems that cannot be effectively solved in the field of concrete engineering. High-performance concrete with high volume and low water-binder ratio, this common engineering quality problem is the main factor affecting the durability of concrete. Concrete shrinkage will have a negative impact, causing cracks in the concrete structure, significantly reducing its abili...

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