摘要
快速、高效分散含有大掺量硅灰、微珠等超细粉体的胶凝材料是制备超高性能混凝土的关键技术。本文通过Zeta电位和总有机碳方法研究了硅灰与聚羧酸减水剂(PCE)的作用关系。结果表明,在纯水溶液中,硅灰表面呈负电性,对PCE及其侧链单体甲基烯丙基聚氧乙烯醚(HPEG)有极强的吸附能力,而对带有负电荷的主链结构聚丙烯酸钠(PAANa)吸附能力较弱。在水泥浆体孔隙溶液中,硅灰的表面仍然呈负电性,但绝对值明显降低,对PCE及其侧链的吸附量有一定的降低,对主链结构的吸附能力增强。根据Langmuir等温吸附方程对吸附测试结果的拟合以及理论计算,可以推断出硅灰在纯水中对聚羧酸侧链结构的吸附性主要来源于氢键作用,这种作用在水泥孔隙溶液中有所减弱。
Rapid and efficient dispersion of cementitious material containing large amounts of silica fume,microspheres,and other ultrafine powders is key technology for preparing ultra-high performance concrete.The interaction relation of polycarboxylate superplasticizer(PCE)and silica fume were studied by Zeta potential and total organic carbon method.The results show that surface charge of silica fume in water is negative,and has strong adsorption to PCE and its side chain monomer methacryloxypropyl polyethylene glycol ether(HPEG),while silica fume has weak adsorption to negatively charged main chain sodium polyacrylate(PAANa).In cement paste pore solution,the Zeta potential of silica fume is still negative,but the absolute value declines significantly,meanwhile the total adsorption amount of PCE and its side chain declines,while the adsorption amount of main chain increases.According to the fitting of Langmuir isotherm equation and theoretical calculation,it suggests that the adsorption of side chain structure of polycarboxylate by silica fume mainly comes from hydrogen bonding,which is weakened in cement paste pore solution.
作者
张建纲
杨勇
毛永琳
周栋梁
李申振
王涛
ZHANG Jiangang;YANG Yong;MAO Yonglin;ZHOU Dongliang;LI Shenzhen;WANG Tao(State Key Laboratory of High Performance Civil Engineering Materials,Jiangsu Sobute New Materials Co.,Ltd.,Nanjing 211108,China;Jiangsu Functional Polyether Engineering Technology Research Center Nanjing,Nanjing Bote New Materials Co.,Ltd.,Nanjing 210047,China)
出处
《硅酸盐通报》
CAS
北大核心
2024年第1期183-190,共8页
Bulletin of the Chinese Ceramic Society
基金
国家自然科学基金青年基金(52108218)。
关键词
聚羧酸减水剂
硅灰
甲基烯丙基聚氧乙烯醚
ZETA电位
吸附
polycarboxylate superplasticizer
silica fume
methacryloxypropyl polyethylene glycol ether
Zeta potential
adsorption
