单茂钛催化剂用于苯乙烯-乙烯嵌段共聚物的合成与表征

乙烯（Ｅ）与苯乙烯（Ｓ）的嵌段共聚合用自制的两种催化剂———茂基三呋喃甲氧基钛［ＣｐＴｉ（ＯＣＨ２Ｏ）３］和茂基三苄氧基钛［ＣｐＴｉ（ＯＣＨ２Ｐｈ）３］进行了研究．考察了促进剂三甲基铝（ＴＭＡ）及乙烯的预聚合时间对聚合结果的影响，发现不同的催化体系有不同的［ＴＭＡ］最佳值以及随着乙烯预聚合时间的延长总的催化效率降低．对嵌段共聚合产物用丁酮、四氢呋喃和氯仿连续萃取分离，得到四氢呋喃中的可溶级分即嵌段共聚物ＰＥ ｂ ｓＰＳ，它占总嵌段共聚合产物的４０ｗｔ％～６０ｗｔ％．对嵌段共聚物用ＤＳＣ、ＷＡＸＤ、ＦＴＩＲ和１３Ｃ ＮＭＲ等方法进行了表征．

SYNTHESIS OF BLOCK COPOLYMER OF ETHENE AND STYRENE WITH NOVEL TITANOCENE CATALYST

The PE b sPS block copolymers were synthesized with η 5 cyclopentadiencyltri furfuryloxyltitanium/MAO and η 5 cyclopentadiencyltribenzyloxyltitanium/MAO catalyst systems respectively.The effect of TMA and ethene prepolymerization time on catalytic efficiency were investigated.The results showed that total catalytic efficiency came down with the increasing of ethene prepolymerization time and the TMA had a optimum value for different catalyst system.The PE b sPS block copolymers were obtained by butanone extraction fractionation.The PE b sPS block copolymers accounted for 40wt%～60wt% of the total copolymerization products and the weight content of styrene segment in the block copolymer is up to 80%～85%.The block copolymers were characterized by DSC,WAXD,FTIR and 13 C NMR methods.