固相氯化法氯化聚乙烯晶粒尺寸的X射线衍射研究

晶粒尺寸的测定常用付里叶变换法^1]和积分宽度法^2],这两种方法都要求样品相应于某个晶面至少存在三个级别的衍射峰,而对聚合物来说,观察到高级衍射峰的情况是很少见的.方差函数法不要求样品存在三个级别的衍射峰,而且方法简单,曾广泛用于金属材料晶粒尺寸和点阵畸变的测定^3-5],但在聚合物材料中的应用甚少^6].本文采用方差函数法对固相氯化法氯化聚乙烯(CPE)和原料聚乙烯(PE)的晶粒尺寸和点阵畸变参数进行了研究,得到了较为满意的结果.

STUDY ON X-RAY DIFFRACTION OF CHLORINATED POLYETHYLENE(CPE)FROM SOLID-PHASE CHLORINATION

In this paper polyethylene(PE)and chlorinated polyethylene(CPE)from solid-phase chlorination were studied by the variance method in x-ray diffractometer.After the deduction of back ground and the corrections for Kαdoublet and the broadening of the instrument, the crystallite sizes and degrees of lattice distortion in PE and CPE were obtained.The results show that(1)With the aid of microcomputer,the method of variance-range function can be used for determining the crystallite size and degree of lattice distortion in polymer;(2)In CPE the crystallite size decreases and the degree of lattice distortion increases with increase of chlorine content when the later is ≤12.0% in the polymer.