文献类型：期刊文章

作　　者：胡文艳[1] 杨敏[1] 赵辛[2] 刘宾元[1] 郝小宇[1] 闫卫东[1]

机构地区：[1]河北工业大学化工学院高分子科学与工程研究所,天津300130 [2]中国人民解放军95989部队,北京100076

出　　处：《高等学校化学学报》

基　　金：国家自然科学基金(批准号:50573018)资助

年　　份：2008

卷　　号：29

期　　号：2

起止页码：430-432

语　　种：中文

收录情况：AJ、BDHX、BDHX2004、CAS、CSCD、CSCD2011_2012、EI(收录号：20081711223363)、IC、JST、RCCSE、RSC、SCIE、SCOPUS、WOS、ZGKJHX、核心刊

摘　　要：A novel catalytic system to prepare branched polyethylene with single catalyst activated by two different co-catalysts is reported in this paper via the tandem catalysis,with ethylene as single monomer.Such catalytic system is composed of β-diketonate zirconium complexes,i.e.(acac)2ZrCl2(Ⅰ)and(dbm)2ZrCl2(Ⅱ)as catalyst precursors,diethylaluminium chloride(AlEt2Cl)as a co-catalyst for ethylene oligomerization and methylaluminoxane(MAO)as another one for the in situ copolymerization with ethylene.The oligomers obtained were mainly α-olefins,and the contents of them in weight were 76.84 for Ⅰ and 65.99 for Ⅱ,while the part being able to be copolymerized was 62.12 and 55.32 for Ⅰ and Ⅱ,respectively.The branched polyethylene via in situ copolymerization of ethylene was prepared by the tandem catalytic system Ⅰ/AlEt2Cl/MAO or Ⅱ/AlEt2Cl/MAO.13C NMR spectrum reveals that the resultant copolymer was branched polyethylene with total branches of 2.1/1000C,including ethyl group of 1.2/1000C,butyl group of 0.8/1000C and longer branches of 0.1/1000C.With increasing the molar ratio of AlEt2Cl to MAO,the melting temperature of the polymer obtained decreased from 133.7 to 116.7 ℃ for Ⅰ/AlEt2Cl/MAO and from 131.7 to 118.8 ℃ for Ⅱ/AlEt2Cl/MAO as well as the change of crystallinity.The catalytic activities for catalyst Ⅰ/AlEt2Cl/MAO and Ⅱ/AlEt2Cl/MAO were from 2.48×104 to 0.10×104 g PE/(mol Zr·h)and from 1.00×104 to 0.32×104 g PE/(mol Zr·h),respectively.The results indicate that the branched polyethylene can be obtained by such a catalytic system.

关 键 词：乙烯原位共聚  支化聚乙烯 β-二酮锆配合物  一氯二乙基铝 甲基铝氧烷

分 类 号：O631]