醋酸乙烯/乙烯共聚可再分散乳胶粉对硅酸盐水泥基饰面砂浆二次泛白的影响(英文)  

Influence of vinyl acetate/ethylene copolymer powder on secondary efflorescence in Portland cement-based decorative mortar

作　　者：Hui-mei ZHU Pei-ming WANG Guo-fang ZHANG 

机构地区：[1]Materials Science & Engineering Mobile Postdoctoral Center, Xi'an University of Architecture and Technology [2]College of Materials & Mineral Resources, Xi'an University of Architecture and Technology [3]Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, Tongji University

出　　处：《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》2015年第2期143-150,共8页浙江大学学报（英文版）A辑（应用物理与工程）

基　　金：Project supported by the National Key Technology R&D Program of China during the 12th Five-year Plan(No.2012BAJ20B02);the National Natural Science Foundation of China(No.51102182)

摘　　要：目的:采用碱浸出量定量评价醋酸乙烯/乙烯共聚可再分散(VAE)乳胶粉对硅酸盐水泥基饰面砂浆二次泛白的影响,并分析其作用机理。创新点:采用定量化手段评价硅酸盐水泥基饰面砂浆的二次泛白程度。方法:1.采用碱浸出率方法定量评价硅酸盐水泥基饰面砂浆的二次泛白程度;2.采用水浸取法测试硅酸盐水泥基饰面砂浆内部可溶性Ca2+、K+和Na+的含量,p H值及可溶性物质总含量等;3.以硅酸盐水泥基饰面砂浆毛细孔失水速率表征其内部水的蒸发速率。结论:1.硅酸盐水泥基饰面砂浆的碱浸出量可用于定量评价其二次泛白程度,碱浸出量越大,二次泛白越严重;当碱浸出量大于1 g/(m2·h)时,硅酸盐水泥基饰面砂浆会呈现出可见二次泛白;2.Ca2+,K+和Na+等碱离子是导致硅酸盐水泥基饰面砂浆二次泛白的主要根源;3.VAE乳胶粉增加了硅酸盐水泥基饰面砂浆内部Ca2+,K+和Na+等碱离子的含量,并且促进它们向表面迁移,增加了碱浸出率,从而促进二次泛白。In this paper, the effect of redispersible vinyl acetate/ethylene copolymer powder （VAE） on the secondary efflo- rescence of Portland cement-based decorative mortar （PCDM） was evaluated by alkalis leachability. The secondary efflorescence substances were investigated using X-ray diffraction （XRD）, X-ray fluorescence （XRF）, and scanning electron microscope （SEM）. The mechanism was also analyzed from the aspect of soluble components in PCDM. The results show that the secondary efflorescence level of PCDM can be quantitatively evaluated by alkalis leachability, with a higher alkali leachability indicating more obvious secondary efflorescence. VAE increases the concentrations of free alkalis ions including Ca^2＋, K^＋, Na^＋ of PCDM, improves the capacity of pore water transmitting ions, increases the alkalis leachability of PCDM, and accordingly promotes the secondary efflorescence of PCDM.

关 键 词：硅酸盐水泥基饰面砂浆 VAE乳胶粉 二次泛白 碱浸出率 

分 类 号：TU578.1[建筑科学—建筑技术科学]