高温丙烯聚合时烷基铝对Ziegler-Natta催化剂定向能力的影响  

Effect of Alkyl Aluminium on Isotacticity of Polypropylene Polymerized at Higher Temperature by Ziegler-Natta Catalyst

作　　者：高明智[1] 刘昆正[2] 丁春敏[2] 李天益[2] 杨菊秀[2] 魏根栓[1] 

机构地区：[1]北京大学 化学院应用化学所,北京100871 [2]北京化工研究院,北京100013

出　　处：《石油化工》2004年第9期838-842,共5页Petrochemical Technology

摘　　要：比较了在70,93℃时不同烷基铝及其浓度对MgCl2／DNBP／TiCl4-AIEt3／DCPDMS(DNBP为邻苯二甲酸二正丁酯,DCPDMS为二环戊基二甲氧基硅烷)催化体系定向能力的影响,并通过NMR,CRYSTAF,DSC及GPC等方法分析了93℃时由不同烷基铝及其浓度下得到的聚合物的微观结构。实验结果表明,温度不同,烷基铝浓度的变化对催化剂定向能力的影响也不同,高温时烷基铝对催化剂性能的影响比较低温度时显著。高温时,三乙基铝浓度的增加将降低催化剂的定向能力,而三异丁基铝浓度的增加则有助于提高催化剂的定向能力。Effects of different alky aluminium and its concentration on isotacticity of polypropylene(PP) by MgCl2/di-n-butyl-phthalate /TiCl4-AlR3/ di-cyclopentyl-di-methoxy-silane system at 70℃ and 93 ℃were compared. Micro-structures of obtained polymers were characterized by NMR,CRYSTAF,DSC and GPC. Effects of concentration variation of cocatalyst on stereospecificity of PP were different at different temperatures. Effect of alkyl aluminium on isospecificity of PP at higher temperature was more obvious than that at lower temperature. Isotacticity of PP decreased with increase in concentration of triethylaluminum, but increased with that of triisobutylaluminum at higher temperature.

关 键 词：丙烯聚合 ZIEGLER-NATTA催化剂 等规度 结晶分级 

分 类 号：O632.12[理学—高分子化学]