Efficient mud inhibition type polycarboxylic acid water reducing agent and preparation method thereof

Abstract

The invention discloses a high-efficiency mud-resistant polycarboxylic acid water reducing agent and a preparation method thereof. The high-efficiency mud-resistant polycarboxylic acid water reducing agent is prepared by copolymerizing an unsaturated polyether monomer and an unsaturated carboxylic acid monomer body and then carrying out amidation reaction with a polyamine compound, wherein the molar ratio of the unsaturated polyether monomer to the unsaturated carboxylic acid monomer to the polyamine compound is 1:(3-5):(0.3-2.5); the use amount of a catalyst, the use amount of an initiator and the use amount of a chain transfer agent contained in the water reducing agent are 0.03-0.3%, 0.5-1.5% and 0.3-1.5% of the total mass of the unsaturated polyether monomer and the unsaturated carboxylic acid monomer respectively. Experiments prove that the polycarboxylate superplasticizer disclosed by the invention has an excellent water reducing and dispersing effect, can still show better fluidity and retention ability under a lower mixing amount, and has obvious advantages compared with a common polycarboxylate superplasticizer under the condition that the mud content of a concrete raw material is higher.

Description

technical field [0001] The invention relates to a high-efficiency mud-suppressing polycarboxylate water reducer and a preparation method thereof, belonging to the technical field of concrete admixtures. Background technique [0002] Polycarboxylate superplasticizer has the advantages of low dosage, high water reducing rate, good slump retention performance, strong molecular structure adjustability, and high performance potential. It has become the third generation of high-performance concrete superplasticizer. Polycarboxylate superplasticizer is a comb-shaped polymer composed of a main chain rich in carboxylic acid groups and side chains of polyethylene oxide. The carboxyl groups on the main chain can be directional adsorbed on positively charged cement or The surface of cement hydrate, while the polyethylene oxide side chain stretches in the solution to form a hydration layer to provide steric repulsion to prevent cement agglomeration, thus giving the cement slurry good flu...

AI Technical Summary

Problems solved by technology

CN109265052A discloses a preparation method of a cross-linked viscosity-reducing polycarboxylate water reducer. While introducing phosphate, carboxylate, quaternary ammonium salt and ester groups into the molecular structure of the polymer, it also makes the polymer structure slightly cross-linked. Linked, the cross-linked viscosity-reducing polycarboxylate superplasticizer not only has viscosity-reducing properties, but also has water-reducing, slump-retaining and mud-resistance properties, which solves the problems of high viscosity and easy The problem of poor performance and rapid loss

After searching, it breaks through the traditional method of preparing polycarboxylate water reducer by aqueous solution method, and obtains conventional polycarboxylate water reducer by copolymerization of unsaturated polyether monomer and unsaturated carboxylic acid monomer under solvent-free conditions; The carboxyl group in the carboxylic acid superplasticizer undergoes an amidation reaction with polyamine compounds to form an amphoteric polycarboxylate superplasticizer whose molecular structure contains both carboxyl anions and amino cations. There is no report on the patent or related literature.