高活性催化剂制备乙烯共聚产物的结构与性能(Ⅰ)支化结构和结晶与熔融行为  

STRUCTURE AND CHARACTERISTICS OF COPOLYMERS OF ETHYLENE/ 1 BUTENE PREPARED WITH HIGHLY ACTIVE CATALYST (Ⅰ) BRANCHING STRUCTURE AND BEHAVIORS OF CRYSTALLIZATION AND MELTING

作　　者：胡锦民[1] 王海华[1] 王森辉[1] 高克京[1] 麦堪成[1] 

机构地区：[1]中山大学高分子研究所,广东广州510275

出　　处：《高分子材料科学与工程》2000年第4期107-110,共4页Polymer Materials Science & Engineering

基　　金：国家自然科学基金;博士点基金资助项目

摘　　要：新型高活性催化剂 Ti Cl4、Ti(OBu) 4/ Mg Cl2 、Si O2 、Zn Cl2 /醇 / Al R3体系催化乙烯气相齐聚和共聚合 ,制得了一系列线性低密度塑性体和极低密度弹性体。用 DSC、FT- IR研究了它们的支化结构、结晶度、结晶与熔融行为。结果表明新型高活性催化剂具有和齐聚性能相关的很好的催化乙烯与 1-丁烯共聚合的性能 ;当共聚单体中 1-丁烯含量由 7% (体积 ,下同 )增加到 2 6 % ,产物的支化度 (乙基数 / 10 0 0 C)从 11.0增大至 47.5的高数值。产物结晶度、熔点随支化度增大而下降 ,当支化度低于 2 4.7时制得的 L L DPE为塑性体 ,而超过 30 .4时获得透明弹性体。弹性体在加热熔融过程中 ,出现熔融双峰 ,而与通常采用乙烯 / 1-丁烯共聚制得的支化度及熔点相近的极低密度聚乙烯(VL DPE)相比 ,具有明显不同的熔融行为。The gas phase oligomerization and copolymerization of ethylene with 1 butene was conducted in the presence of highly active catalyst system consisting TiCl 4,Ti(OBu) 4/MgCl 2,SiO 2,ZnCl 2/alcohol/AlR 3 by fluided bed prosess. The LLDPE plastics and VLDPE elastomers had been prepared. The branching degrees, melting points and crystallinity of the products were measured by DSC and FT IR. The results show that the catalytic system exhibits characteristics of oligomerization and very highly copolymerization of ethylene with 1 butene. When the content of 1 butene feed from 7%(V) to 26%(V), the branching degrees of copolymers increase from 11.0 to 47.5 ethyl/1000C. As branching degrees increase, the melting points and crystallization temperature and crystallinity of the products decrease. As the branching degrees are lower than 24.7 the copolymers are LLDPE plastics, while, as branching degrees are higher than 30.4 the products are elastomers. The DSC curve of the elastomer showed double melting behavior.

关 键 词：共聚合 支化度 聚乙烯 结构 结晶 性能 熔融行为 

分 类 号：TQ325.12[化学工程—合成树脂塑料工业] O631.11[理学—高分子化学]