聚羧酸减水剂分子结构对含膨润土水泥砂浆流动性的影响.pdfVIP

学兔兔 2014年第 11期(总第 301期 ) 混 凝 土 预 拌 砂 浆 Number 1 1 in 2014(Total No 301) Concrete READY MIXED MORTAR 聚羧酸减水剂分子结构对 含膨润土水泥砂浆流动性的影响 王伟山1_ ，冯中军1l2，邓最亮1I ，傅乐峰1l2，郑柏存1,2 (1．上海建筑外加剂工程技术研究中心，上海 200232；2．上海三瑞高分子材料有限公司，上海 200232) 摘 要：研究了聚羧酸减水剂分子结构变化对其在膨润土表面的吸附量的影响，考察了膨润土颗粒的Zeta电位、含膨润土水泥 净浆的流变性能和砂浆的流动度随聚羧酸减水剂分子结构的变化。结果表明，增大羧基密度和延长聚氧乙烯侧链长度均有利于 减小膨润土对聚羧酸减水剂的吸附量，醚类聚羧酸减水剂的吸附量远低于酯类聚羧酸减水剂。提高醚类聚羧酸减水剂的羧基密 度和侧链长度均有利于改善含膨润土砂浆的流动性。 关键词： 聚羧酸；减水剂；分子结构；吸附；流动度 中图分类号：TU528．042．2 文献标志码：A 文章编号： 1002—3550(2014)11—0132—04 Effect of molecular structure of polycarboxylate water reducer on the fiowability of cement mortar containing bentonite WANGWeishan1,2，FENGZhongjun ，DENGZuiliang ，FULefeng 一，ZHENGBaieun ’ (1．Shanghai Engineering Research Center for Construction Admixtures，Shanghai 200232，China； 2．Shanghai Sunrise Polymer Co．，Ltd．，Shanghai 200232，China) Abstract： The effect ofmolecular structure ofpolyearboxylate water reducer on its adsorption amount onto bentonite was investigated， andthe variationsinZetapotential ofbentoniteparticles，rheologieal properties ofcementpaste containingbentonite andfluidity ofcement mortar containing bentonite due to the change ofmolecular structure ofpolycarboxylate water reducer．The results indicated that larger car— boxyl density and longer polyoxyethylene side chain were favorable for decreasing the adsorption amount ofpolycarboxylate water reducer onto bentonite．The adsorption amount of ether—based polycarboxylate water reducer onto bentonite was much less than that of ester-based polycarboxylate water reducer．The flowablity of cement mortar with bentonite