A kind of preparation method of cross-linked viscosity-reducing polycarboxylate water reducer

Abstract

A preparation method for a crosslinked viscosity-reducing polycarboxylic acid water reducer, comprising the following steps: (1) preparing an esterified monomer; (2) performing a copolymerization reaction; and (3) performing a neutralization reaction. The crosslinked viscosity-reducing polycarboxylic acid water reducer is prepared from the copolymerization of the following components: esterified monomers prepared by esterification reactions of an allyl alcohol monomer with 2-phosphonobutane-1,2,4-tricarboxylic acid, which comprise a product obtained by esterifying one carboxyl group in 2-phosphonobutane-1,2,4-tricarboxylic acid and a small amount of products obtained by esterifying two carboxyl groups and esterifying three carboxyl groups in the 2-phosphonobutane-1,2,4-tricarboxylic acid, a polyether macromonomer, 2-methacryloyloxyethyl choline phosphate and an unsaturated acid, so that said polymer has a lightly crosslinked structure while a phosphate, a carboxylate, a quaternary ammonium salt and an ester group are introduced into the structure of the polymer.

Description

technical field [0001] The invention belongs to the technical field of building admixtures, and in particular relates to a preparation method of a cross-linked viscosity-reducing polycarboxylate water reducer. Background technique [0002] Polycarboxylate superplasticizer has the advantages of low dosage, high water reducing rate, strong designability and environmental friendliness, and has become the most widely used concrete admixture. High-rise and ultra-high-rise buildings require concrete to reach a certain level of strength. The pumping construction of high-rise building concrete also has high requirements on the workability of concrete. Ratio, increasing the amount of cementitious materials, increasing the proportion of mineral admixtures, etc., but these measures will also cause problems such as increased concrete viscosity and decreased fluidity. Agent or use viscosity-reducing polycarboxylate superplasticizer to solve these problems. However, with the rapid incre...

AI Technical Summary

Problems solved by technology

High-rise and ultra-high-rise buildings require concrete to reach a certain level of strength. The pumping construction of concrete in high-rise buildings also has high requirements for the workability of concrete. Ratio, increasing the amount of cementitious materials, increasing the proportion of mineral admixtures, etc., but these measures will also cause problems such as increased concrete viscosity and decreased fluidity. agent or use viscosity-reducing polycarboxylate superplasticizer to solve these problems

However, with the rapid increase in the amount of infrastructure projects, the consumption of sand and gravel is huge, the resources of high-quality sand and gravel are getting less and less, and the mud content in sand and gravel is gradually increasing. The amount is very sensitive, which makes the dispersibility and dispersion retention of polycarboxylate superplasticizer decrease

Images