聚羧酸系减水剂的构性关系及其作用机理研究

聚羧酸系减水剂作为一种高性能减水剂,目前已成为国内外研究与发展的热点。概述了近几年国内外高效减水剂的研究与发展现状,阐述了聚羧酸系高效减水剂的分子结构、性能特点及作用机理,分子主链上阴离子基团越多及聚氧乙烯长侧链越长,聚羧酸系减水剂的分散性能和流动保持性能越好。聚羧酸系减水剂主要依靠聚氧乙烯长侧链的位阻效应和羧基及磺酸基的静电斥力来分散水泥颗粒。最后,提出了减水剂在应用中存在的问题并展望了其发展趋势。

Study on the Structure and Performances and Acting Mechanisms of Polycarboaylate-type Superplasticizers

As a high performance superplasticizer,the research and development of polycarboxylate-type superplasticizers have become more popular recently at home and abroad.The research status of the superplasticizers is summarized in recent years,and the chemical structure,performances and adsorption mechanisms are discussed.The more anion groups and the longer polyoxyethylene side chains on the copolymer main chain,the better dispersing and retarding performance of polycarboxylate-type superplasticizers are obtained.Polycarboxylate-type superplasticizers depend mainly on the steric hindrance effect of polyoxyethylene side chains and the electrostatic repulsion of-COO-and-SO3-groups.Finally,the problem of superplasticizers in application and the development trends are proposed.