聚羧酸系保坍剂的低温制备及性能

Study on low temperature synthesis and performance of polycarboxylate slump retaining agent

采用异戊烯醇聚氧乙烯醚、马来酸酐、丙烯酰胺、丙烯酸羟丙酯及甲基丙烯磺酸钠等单体,低温制备了一种聚羧酸系保坍剂CHS-101,并对所制备保坍剂的水泥净浆流动度、Zeta电位及混凝土性能进行了比较。结果表明:与聚羧酸系减水剂及与2种市售保坍剂相比,掺聚羧酸系保坍剂CHS-101的水泥净浆初始流动度较低,但随时间延长明显增大,性能也占优;掺CHS-101水泥颗粒的Zeta电位绝对值下降的幅度更小,从而可以保持水泥净浆较高的经时流动度;CHS-101聚羧酸系保坍剂对大坍落度和小坍落度混凝土都具有良好的保塑效果,且对强度无影响。

A type of polycarboxylate slump retaining agent CHS-101 was synthesized at low temperature using monomer such as isoprenol ether, maleic anhydride, acrylamide, hydrexypropyl acrylate and methyl allylsulfonate, etc. The performances of C HS-101 including cement paste, zeta potential and concrete properties were studied. The results show that the initial cement paste adding CHS-101 is smaller than polycarboxylatesuperplasticizer and other slump retaining agents,the zeta potential of cement particles adding CHS-101 decline smaller than other admixtures which is reason of cement paste behavior. Whether to big or small slump concrete,the slump retention capability of concrete using polycarboxylate slump retaining agent and superplasticizer composition is much better than which using polycarboxylatesuperplasticizer only.