A high-efficiency mud-suppressing polycarboxylate water reducer and its preparation method

Abstract

The invention discloses a high-efficiency anti-mud polycarboxylic acid water-reducing agent and a preparation method thereof. It is prepared by bulk copolymerization of unsaturated polyether monomers and unsaturated carboxylic acid monomers, and then through amidation reaction with polyamine compounds. Obtained; wherein the molar ratio of unsaturated polyether monomer, unsaturated carboxylic acid monomer and polyamine compound is 1:3~5:0.3~2.5; the amount of catalyst, initiator contained in the water reducing agent, The dosage of chain transfer agent is 0.03-0.3%, 0.5-1.5%, and 0.3-1.5% of the total mass of unsaturated polyether monomer and unsaturated carboxylic acid monomer respectively. Experiments have confirmed that the polycarboxylate water-reducing agent of the present invention has excellent water-reducing and dispersing effects, and can still show good fluidity and retention ability at lower dosages. When the mud content of the concrete raw materials is high, It has obvious advantages over ordinary polycarboxylate water-reducing agents.

Description

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

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.