m-PE-LLD/PE-LD共混物结晶结构的研究  

Study on Crystal Structure of m-PE-LLD/PE-LD Blends

作　　者：吴彤[1] 宋亮[1] 赵磊[1] 吴丝竹[1] 吴刚[1] 

机构地区：[1]北京化工大学材料科学与工程学院北京市新型高分子材料制备与加工重点实验室,北京100029

出　　处：《中国塑料》2005年第1期34-38,共5页China Plastics

摘　　要：采用DSC、WAXD和SAXS相结合的方法研究了共混物的相分离、结晶度、片晶厚度等结晶结构参数。研究结果表明 ,在m PE LLD/PE LD共混物中 ,当PE LD含量较大时无论是熔融曲线还是降温曲线都只出现一个峰 ,说明两者存在共结晶 ,有很好的相容性。当PE LD含量减小时 ,共混物出现相分离 ,升、降温曲线均出现双峰 ,但两峰值呈现靠近趋势 ,预示m PE LLD/PE LD共混物中仍存在少量共结晶。WAXD数据显示 ,PE LD添加到m PE LLD中 ,没有改变茂金属聚乙烯固有的晶体结构 ,共混物仍然保持了聚乙烯的正交晶系结构。并随着PE LD在m PE LLD中添加比例的增加 ,共混物正交晶系增强的同时晶粒尺寸变小。The phase separation, crystallinity and lamellae thickness of the blends of metallocene linear low density polyethylene (m-PE-LLD) and low density polyethylene (PE-LD) were studied via DSC, WAXD and SAXS determinations. When the fraction of PE-LD was 80 %, only one melting and one crystallizing peak appeared on the DSC trace, which indicated that the two components possessed good compatibility and co-crystallization occurred. As PE-LD content decreased, phase separation took place and two peaks were observed on both melting and cooling traces. WAXD analysis showed that the intrinsic crystal structure of m-PE-LLD was not affected with the addition of PE-LD. As PE-LD content increased, the size of the crystallites decreased.

关 键 词：茂金属线形低密度聚乙烯 低密度聚乙烯 广角X射线衍射 小角X射线散射 结晶结构 

分 类 号：TQ325.12[化学工程—合成树脂塑料工业]