泥对掺聚羧酸减水剂的水泥浆体分散性的影响  

Effects of clay on the dispersibility of cement paste mixed with polycarboxylate superplasticizer

作　　者：李有光[1] 李苑[1] 万煜[2] 邓成[1] 王智[2] 钱觉时[1] 

机构地区：[1]重庆大学材料科学与工程学院,重庆400044 [2]重庆大学化学化工学院,重庆400044

出　　处：《重庆大学学报（自然科学版）》2012年第1期86-92,共7页Journal of Chongqing University

基　　金：国家重点基础研究发展计划项目(2009CB623104);高性能土木工程材料国家重点实验室开放基金课题(2010CEM004);重庆大学'211工程'三期建设研究生开放实验室资助项目

摘　　要：为了揭示含泥量对聚羧酸减水剂分散能力的影响,试验选择净浆流动度和黏度两个指标,研究泥对掺聚羧酸减水剂水泥浆体流变性质的影响,并利用IR、UV手段分析确定了泥的滤液对聚羧酸减水剂分子结构的影响及碱性环境中聚羧酸减水剂在泥颗粒表面的吸附规律。结果表明:当泥取代水泥质量的15%时,聚羧酸减水剂由于泥的存在已无分散效果;增大聚羧酸减水剂掺量可以提高含泥水泥浆体的分散性;泥的滤液不会改变聚羧酸减水剂的分子结构、对聚羧酸减水剂的分散能力无不利影响;在饱和石灰水模拟的碱性环境中,泥对减水剂的吸附很快,初始时间里(6min内)泥就已经充分吸附了聚羧酸减水剂,泥对聚羧酸减水剂的吸附量为水泥的4倍左右。To reveal the effect of clay on the dispersibility of polycarboxylate superplasticizer （PC）, the fluidity and viscosity of cement paste are chosen as performance indexes to study the effect of clay on the theological properties of cement paste mixed with PC. The influence of filtrate of clay on molecular structure and the regularity of adsorption of PC on the surface of clay particles in alkaline environment are also analyzed by IR and UV. The results show that PC has no dispersing effect on the cement paste when clay content reaches to 15%. Increasing the dosage of PC can reduce the negative impact of clay. The filtrate of clay can＇t change the molecular structure of PC and doesn＇t affect the dispersibility of PC. In simulated alkaline environment （saturated solution of calcium hydroxide）, the adsorption speed of clay on PC is rapid, whose adsorption capacity of clay on PC is about 4 times of cement＇s, and clay will have been reached its equilibrium adsorption amount in the initial period （within 6 min）.

关 键 词：泥 聚羧酸减水剂 分散性 吸附 碱性环境 

分 类 号：TU528.042.2[建筑科学—建筑技术科学]