有机蒙脱土的制备与性能表征

本文采用十六烷基三甲基溴化铵、十八烷基三甲基氯化铵和双十八烷基二甲基氯化铵分别对蒙脱土进行有机改性,对样品进行了X-射线衍射、红外光谱和热稳定性分析。结果表明三种插层剂均已进入蒙脱土的层间,有机蒙脱土的层间距由1.54nm分别增加到2.14nm、2.84nm和3.80nm。通过对蒙脱土改性前后DTA和TG分析,发现经过有机化改性后的蒙脱土对层间水分子的吸附明显变弱,吸附水和结构水的脱除温度明显降低。实验结果证明,有机季铵阳离子完全可以插层进入蒙脱土层间,并且随着有机改性剂碳链的增长,蒙脱土的层间距增大。同时,有机改性剂进入蒙脱土晶层中明显改变了蒙脱土表面的亲疏水性能,使其由亲水性变为疏水性,这对利用有机蒙脱土制备纳米复合材料具有一定的指导意义。

The Preparation and Characterization of Organic Montmorillonite

This article using hexadecyl trimethyl ammonium bromide,the octadecyl trimethyl ammonium chloride and the double octadecyl dimethyl ammonium chloride to intercalated modification on the montmorillonite separately.And doing the X-ray diffraction,the infrared spectrum and the thermostable analysis on the sample.The result showed that three kinds of intercalators all have entered the intercalation of montmorillonite interlayer,organic montmorillonite layer spacing increases from 1.54nm to 2.14nm,2.84nm and 3.80nm separately.The DTA and the TG analysis for the montmorillonite clay before and after the modification indicates that the montmorillonite clay weakens the interplayer water molecule adsorption obviously,the temperature of adsorbing water and the structure water decreased significantly,after the organizing modification.This experimental result proved that the organic quaternary ammonium cation definitely can insert into the clay layers,and the montmorillonite clay layer spacing is increasing along with the organic modifier carbon chain's growth.At the same time,the entry of organic modifiers montmorillonite layers significant changed on the surface of the montmorillonite affinities water properties,from hydrophilic to hydrophobic,providing the thinking of utilizing the organic montmorillonite clay preparation of nanocomposites.