Influences of superplasticizer, polymer latexes and asphalt emulsions on the pore structure and impermeability of hardened cementitious materials
Influences of superplasticizer, polymer latexes and asphalt emulsions on the pore structure and impermeability of hardened cementitious materials
复制标题
高效减水剂、聚合物乳胶和沥青乳液对硬化胶凝材料孔隙结构和抗渗性能的影响
DOI：
10.1016/j.conbuildmat.2013.11.104
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发表时间：
2014-02
影响因子：
7.4
通讯作者：
Kong Xiangming
中科院分区：
文献类型：
--
作者：
Zhang Yanrong;Zhang Yanrong;Kong Xiangming;Kong Xiangming
采用分子/粒径从纳米到微米不同的三种混凝土和砂浆中常用的聚合物（聚羧酸减水剂、聚丙烯酸酯乳液和沥青乳液）来研究它们对硬化水泥浆体孔结构和硬化砂浆抗渗性的影响。分别采用压汞法和交流阻抗法测定固化7天和28天的硬化体的孔隙结构和抗渗性能。结果表明，高效减水剂的掺入明显减小了平均孔径，提高了抗渗性。当用量高于3%时，聚丙烯酸酯乳液还会导致孔径减小，从而增强抗渗性。在相同用量下，聚合物粒径较小的乳胶比粒径较大的乳胶具有更好的增塑效果，能更有效地降低平均孔径，增强抗渗性能。同样，沥青乳液也有利于抗渗性的增强，阴离子沥青乳液的塑化效果更好，比阳离子沥青乳液具有更强的抗渗性。人们认为，对于高效减水剂来说，增塑效果是细化孔隙结构和增强抗渗性的主要控制因素。对于聚合物乳胶和沥青乳液来说，低剂量时塑化作用发挥积极作用，高剂量时填充作用在减小孔径和增强抗渗性方面占主导地位。
Three types of polymers commonly used in concrete and mortar (polycarboxylate superplasticizer, polyacrylate latexes and asphalt emulsions) which differ in molecular/particle size from nanometer to micron were employed to investigate their effects on the pore structure of hardened cement pastes and the impermeability of hardened mortars. The pore structure and the impermeability of the hardened ones cured for 7 days and 28 days were measured by mercury intrusion porosimetry and alternating current impedance, respectively. Results show the incorporation of superplasticizer obviously reduces the average pore size and enhances the impermeability. The polyacrylate latexes also lead to the decline in pore size and consequently the enhanced impermeability at dosage higher than 3%. At the same dosage, latex with smaller polymer particle size is more effective in reducing the average pore size and enhancing the impermeability than that with larger particle size due to its better plasticizing effect. Similarly, asphalt emulsions also facilitate the enhancement in impermeability, and the anionic asphalt emulsion with better plasticizing effects brings about stronger impermeability than the cationic one. It is believed that for superplasticizer, the plasticizing effect is the main controlling factor for the finer pore structure and the enhanced impermeability. In the case of polymer latexes and asphalt emulsions, the plasticizing effect contributes actively at low dosage and the filling effect is dominant at high dosage in terms of declining pore size and augmenting impermeability.
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影响因子：
3.8
作者：
Beeldens, A;Van Gemert, D;Czarnecki, L
通讯作者：
Czarnecki, L
影响因子：
10.5
作者：
L. Woo;S. Wansom;N. Ozyurt;B. Mu;Surendra P. Shah;T. Mason
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L. Woo;S. Wansom;N. Ozyurt;B. Mu;Surendra P. Shah;T. Mason
影响因子：
11.4
作者：
Levy, SM;Helene, P
通讯作者：
Helene, P
影响因子：
11.4
作者：
W. McCarter;R. Brousseau
通讯作者：
W. McCarter;R. Brousseau
影响因子：
11.4
作者：
D. A. Silva;P. Monteiro
通讯作者：
D. A. Silva;P. Monteiro