聚丙烯酸酯乳液改性砂浆微观结构与改性机理  

Microstructure and modification mechanism of polyacrylate latex modified mortars

作　　者：李蓓[1] 田野[1] 赵若轶[2] 段安[1] 李宗津[3] 马红岩[3] 

机构地区：[1]浙江大学建筑工程学院,浙江杭州310058 [2]浙江工商大学艺术设计学院,浙江杭州310018 [3]香港科技大学土木与环境工程系香港

出　　处：《浙江大学学报（工学版）》2014年第8期1345-1352,1361,共9页Journal of Zhejiang University：Engineering Science

基　　金：国家自然科学基金资助项目(51008272,51108413);高等学校博士学科点专项资助项目(20100101120061);中央高校基本科研业务费专项资金资助项目(2012QNA4016);浙江省重点科技创新团队资助项目(2010R50034)

摘　　要：为了研究聚丙烯酸酯乳液(PA)改性砂浆硬化过程中微观结构的形成过程及改性机理,分析PA聚合物乳液在新拌水泥砂浆中的吸附特性,并模拟孔隙溶液和PA乳液之间相互作用.同时采用扫描电子显微镜(SEM)和能谱分析(EDX)法表征了PA改性砂浆微观结构的演化过程.试验结果表明,PA颗粒将与孔隙溶液中的钙离子发生化学反应,PA聚合物将以不同的形态吸附在水泥砂浆的局部部位.在此基础上,考虑PA聚合物改性乳液与水泥基材料的反应,提出一种改进的聚合物改性与微观结构形成模型.这对研究聚合物改性水泥基材料的力学性能与推广聚合物改性水泥基材料在工程中的应用具有重要意义.In order to study the microstructure forming process and modification mechanism of polyacrylate （PA） latex modified mortars during the hardening process, the adsorption performance of PA latex in fresh mortars was analyzed, and the interaction between PA latex and pore solution was simulated. Meanwhile, the microstructure evolution of PA modified mortars was measured by Scanning Electron Microscope （SEM） and Energy Dispersive X-ray Detector （EDX） analysis. The test results show that PA particles chemically react with calcium ions in the pore solution and PA polymer is localized at some places within cement mortar through different morphologies. Based on these experiments, in considering the reactions between PA latex and cement-based materials, an improved polymer modification and microstructure formation model is proposed. This is of great importance for the investigation on the mechanical properties of polymer modified cement-based materials and the application of polymer modified cement-based materials in civil engineering.

关 键 词：聚合物改性水泥砂浆 微观结构 聚合物改性机理 聚合物乳液 表面活性剂 

分 类 号：TU411[建筑科学—岩土工程] TU472[建筑科学—土工工程]