物理化学学报 >> 2013, Vol. 29 >> Issue (06): 1260-1265.doi: 10.3866/PKU.WHXB201303262

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胶体粒子表面有效电荷的实验测量

周宏伟1, 米利1,2, 刘丽霞1, 徐升华1, 孙祉伟1   

  1. 1 中国科学院力学研究所微重力重点实验室, 北京 100190;
    2 山东师范大学化学化工与材料科学学院, 济南 250014
  • 收稿日期:2012-12-27 修回日期:2013-03-26 发布日期:2013-05-17
  • 通讯作者: 徐升华 E-mail:xush@imech.ac.cn
  • 基金资助:

    国家自然科学基金(11172302, 11032011)资助项目

Experimental Measurements of the Surface Effective Charge of Colloidal Particles

ZHOU Hong-Wei1, MI Li1,2, LIU Li-Xia1, XU Sheng-hua1, SUN Zhi-Wei1   

  1. 1 Key Laboratory of Microgravity, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, P. R. China;
    2 College of Chemistry, Chemical Engineering and Material Science, Shandong Normal University, Jinan 250014, P. R. China
  • Received:2012-12-27 Revised:2013-03-26 Published:2013-05-17
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (11172302, 11032011).

摘要:

胶体溶液中带电胶粒的有效电荷是计算粒子间相互作用势的一个重要参数. 在本文中用电导率-粒子数密度关系法和电导滴定法分别研究了七种粒径及表面带电情况均不相同的聚苯乙烯粒子, 结果显示两种测量方法得到的有效电荷数值具有较好的一致性, 误差在7%以内. 同时发现, 经验公式计算的有效电荷差不多是实验值的2倍, 表明文献中的经验公式对于本文所研究的胶体粒子体系不适用.

关键词: 胶体晶体, 有效电荷, 相互作用, 电导滴定

Abstract:

The effective surface charge of colloidal particles is an important parameter for calculating inter-particle interaction potentials. In this study, we investigated the effective charge of seven kinds of polystyrene particles having different diameters and surface charges. Two methods, conductivity-number density relationships and conductometric titration, were used to measure the effective charges. The results obtained from the two different methods show small variations of 7%. The effective charges were also calculated from empirical formulas and found to be twice as large as the experimental values, indicating these formulas cannot be universally applied to all colloidal dispersions.

Key words: Colloidal crystal, Effective charge, Interaction, Conductometric titration