摘要
采用4种不同外给电子体,在5L不锈钢高压反应釜中对DQC催化剂进行丙烯液相本体聚合的研究。实验结果表明,以二环戊基二甲氧基硅烷(DCPDMS)和二异丙基二甲氧基硅烷(DIPDMS)为外给电子体时可得到较高等规度的聚合物,且聚合物具有较宽的相对分子质量分布;以DCPDMS为外给电子体时得到的聚合物的数均相对分子质量和重均相对分子质量最大;在生产低熔体流动指数聚合物时,以甲基环己基二甲氧基硅烷(CHMMS)为外给电子体时聚合物具有更敏感的氢调性能;以二异丁基二甲氧基硅烷(DIBDMS)和DCPDMS为外给电子体时,预络合时间对催化剂活性的影响较小;以DIBDMS为外给电子体时,DQC催化剂在氢调敏感性、高氢加入量时催化剂活性、预络合时间对催化剂活性的影响以及催化剂活性衰减等方面均优于另外3种外给电子体。
The effects of four different external electron donors （dicyclopentyl dimethoxy silane （ DCPDMS）, diisopropyl dimethoxy silane （ DIPDMS）, diisobutyl dimethoxy silane （DIBDMS） and cyclohexyl methyl dimethoxy silane （CHMMS）） on the bulk polymerization of propylene with DQC catalyst system were studied in a five-liter reactor. Polypropylene with higher isotacticity and broader distribution of relative molecular mass were obtained when DCPDMS and DIPDMS were used as the external donors. Both the number-average and the weight-average relative molecular masses were higher with DCPDMS than those with the other three external donors. Use of CHMMS gave the catalyst system better hydrogen sensitivity in production of the low melt-index polypropylene. The effect of precompounding time on the catalyst activity was smaller in using either DIBDMS or DCPDMS. When DIBDMS was used as the external electron donor, the comprehensive performances of the catalyst system, namely hydrogen sensitivity, polymerization activity （more hydrogen addition）, precompounding time and activity decay were best among the four catalyst systems with the four electron donors.
出处
《石油化工》
CAS
CSCD
北大核心
2011年第4期381-386,共6页
Petrochemical Technology
关键词
外给电子体
DQC催化剂
聚丙烯
丙烯聚合
external electron donor
DQC catalyst
polypropylene
propylene polymerization
