蒙脱石层电荷与有机改性蒙脱石凝胶性能关系研究

STUDY ON RELATION BETWEEN LAYER CHARGE AND GEL PERFORMANCE OF ORGANIC MONTMORILLONITE

利用自然沉降法提取了山东两不同产地膨润土中的钙基蒙脱石矿物M1和M2,利用结构式推算法计算了两提纯蒙脱石的层电荷:M1单位半晶胞的层电荷为0.38,M2单位半晶胞的层电荷为0.59;利用十八烷基三甲基氯化铵对蒙脱石进行有机改性,并对有机蒙脱石凝胶性能和层电荷的相关关系进行研究。研究发现:蒙脱石单位半晶胞的层电荷越低,在水中的分散性越好,越有利于十八烷基三甲基铵阳离子的插层,相应有机改性蒙脱石在二甲苯和乙醇体系中的凝胶性能越好(如M1);蒙脱石单位半晶胞的层电荷越高,在水中的分散性越差,越不利于十八烷基三甲基铵阳离子的插层,相应有机改性蒙脱石产品的凝胶性能较差(如M2)。

By means of natural sedimentation, two raw bentonite samples from Shandong Province were purified, layer charge of the two purified montmorillonite samples（M1 and M2 ）were calculated by way of crystal structure formula. The calculation results showed that the layer charge per half crystal cell of M1 was 0.38,the layer charge per half crystal cell of M2 was 0.59. The two purified montmorillonite samples were organically modified by Octadecyl Trimethyl Ammonium Chloride,the correlation between the layer charge and gel performance of organic montmorillonite was revealed that the lower the layer charge of montmorillonite,the better the decentralization of montmorillonite in water, which are propitious to Octadecyl Trimethyl Ammonium cation inserting into the interlayer of montmorillqnite. Therefore, the prepared organic montmoriltonite has better gel performance （such as M1）than the one prepared from montmorillonite with higher layer charge （such as M2）.