Preparation method of cross-linked viscosity-reducing polycarboxylate water reducer

Abstract

The invention discloses a preparation method of a cross-linked viscosity-reducing polycarboxylate water reducer. The preparation method comprises the following steps: (1) preparing esterification monomers; (2) performing the copolymerization reaction; and (3) performing the neutralization reaction. According to the preparation method of the invention, allyl alcohol monomers are copolymerized withesterification monomers obtained by esterifying two or three carboxyl groups in little 2-butane phosphate-1,2,4-tricarboxylic acid, polyether macro momoners, 2-methyl allyl oxyethyl phosphorylcholineand unsaturated acid prepare the cross-linked viscosity-reducing polycarboxylate water reducer, and while phosphate, carboxylate radicals, quaternary ammonium salt and ester groups are introduced intoa polymer molecular structure, the polymer structure is slightly cross-linked. The cross-linked viscosity-reducing polycarboxylate water reducer prepared by the method has viscosity reducing performance, also has water reducing, slump loss resisting and mud resisting properties, and solves the problems of high viscosity, poor mixing property and fast loss due to high mud content in a concrete rawmaterial.

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...

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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

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