聚羧酸系高效减水剂的近期研究进展

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聚羧酸系高效减水剂(PC)越来越广泛的应用于混凝土中,特别是自密实混凝土(SCC)。与木质素磺酸盐、密胺或者萘系减水剂相比,尽管聚羧酸系高效减水剂在一些方面有显著优点,比如,高减水率、水泥颗粒分散性好、掺量低、对水泥成分的敏感性小、保坍好而不延长混凝土的凝结硬化时间等。但传统的聚羧酸系高效减水剂在许多情况下还是难以满足要求,特别是对于自密实混凝土。而通过改变聚羧酸分子中主链、枝链和羧基的化学结构,可以实现保坍、凝结控制、减缩等多种功能。满足高性能自密实混凝-土的设计和施工的需要。本文综述了近期发展的一些新型聚羧酸系高效减水剂。 Polycarboxylate superplasticizer (PC) is more and more widely used in concrete, especially self-compacting concrete (SCC). Although polycarboxylate superplasticizers have significant advantages over lignosulfonates, melamine or naphthalene superplasticizers in some respects, such as high water reduction rates, good cement particle dispersibility, low dosage , The sensitivity of the cement composition is small, good Paul slump does not extend the concrete hardening time. However, the traditional polycarboxylate superplasticizer in many cases is still difficult to meet the requirements, especially for self-compacting concrete. By changing the chemical structure of the main chain, the branch chain and the carboxyl group in the polycarboxylic acid molecule, various functions such as slump retention, coagulation control and reduction can be achieved. Meet the needs of high-performance self-compacting coagulation - soil design and construction. This article reviews some recent developments of polycarboxylate based superplasticizers.
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