Mud-proof slump-retaining type polycarboxylate superplasticizer with low shrinkage and high adaptability and low-temperature preparation method thereof

Abstract

The invention discloses a mud-proof slump-retaining type polycarboxylate superplasticizer with low shrinkage and high adaptability and a low-temperature preparation method thereof. The polycarboxylatesuperplasticizer is mainly prepared by the following steps: carrying out free radical polymerization on 4-hydroxybutylvinyl polyoxyethylene ether, unsaturated carboxylic acid, an unsaturated amide-type monomer, dipolyethylene glycol maleate, an unsaturated quaternary ammonium cationic monomer, an oxidizing agent, a catalyst, a reducing agent, a chain transfer agent and deionized water at 5-15 DEGC through an aqueous solution, regulating pH value by adding a sodium hydroxide solution, and supplementing water. The preparation method of the invention has advantages of low-temperature production, no heat source, simple equipment, no pollution, short reaction time and high production efficiency. The prepared mud-proof slump-retaining type polycarboxylate superplasticizer endows concrete withgood workability, good adaptability, low shrinkage and high strength, has excellent mud-proof slump-retaining property, and greatly reduces construction difficulty.

Description

technical field [0001] The invention relates to the technical field of water reducer improvement, in particular to a low-shrinkage, high-adaptability mud-resistance and slump-preserving polycarboxylate water reducer and a low-temperature preparation method thereof. Background technique [0002] Polycarboxylate superplasticizer is widely used as a contemporary high-performance water reducer and has become an indispensable component in concrete. Polycarboxylate superplasticizer has high water reducing rate, good slump retention, and molecular structure can be designed It is widely used in the preparation of high-performance concrete for highways, railways, bridges, and high-rise construction projects. However, the main problems of polycarboxylate superplasticizers are that the homogeneity of large monomers is too serious, and the requirements for serialization and functionalization are relatively prominent; the shrinkage of high-performance and high-strength concrete leads to ...

AI Technical Summary

Problems solved by technology

However, the main problems of polycarboxylate superplasticizers are that the homogeneity of large monomers is too serious, and the requirements for serialization and functionalization are relatively prominent; the shrinkage of high-performance and high-strength concrete leads to concrete cracking; the high mud content of sand and gravel aggregates It leads to too fast loss of slump; it is sensitive to changes in cement, coal ash and other silty materials, and poor sand and gravel gradation, which makes the workability of concrete worse, and bleeding and bottoming are prone to occur, resulting in concrete Decreased work performance

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