氰基琥珀酸酯为内给电子体的丙烯聚合催化剂

Propylene polymerization catalyst based on the cyano succinate internal donor

以2-氰基-2,3-二异丙基琥珀酸二乙酯(CDIPS)为内给电子体制备了Zielgler-Natta丙烯聚合催化剂(记为CDIPS催化剂),通过本体聚合及中试评价研究了催化剂的性能,并利用^(13)C NMR,DSC,GPC等方法对制备的聚丙烯进行了表征。实验结果表明,CDIPS含量适宜的催化剂具有良好的综合性能,如高活性和高定向性,制备的聚合物粉料形态良好,堆密度高。与含邻苯二甲酸酯内给电子体的参比催化剂相比,CDIPS催化剂的氢调性能和对外给电子体的响应均不敏感。CDIPS催化剂可应用于气相聚丙烯工艺制备相对分子质量分布较宽的聚丙烯。当制备低溶体流动速率产品时,CDIPS催化剂的优势更明显,所得产品的拉伸模量、弯曲模量和常温冲击强度均优于参比催化剂。

With diethyl 2-cyano-2,3-diisopropyl-succinate（CDIPS） as internal electron donor, Ziegler-Natta propylene polymerization catalyst（CDIPS catalyst） was prepared. Its properties were studied via bulk polymerization and continuous gas phase pilot test, and the properties of the corresponding polypropylene（PP） were characterized by 13C NMR, DSC, and GPC et al. The results show that the catalyst containing appropriate CDIPS has good comprehensive performance, such as high activity, high stereospecificity, good particle morphology and high bulk density of polymer powder. Compared with the Ref. catalyst using phthalate as internal donor, the CDIPS catalyst has a significantly low response to hydrogen and silane external donor. CDIPS catalyst can be used on gas phase propylene polymerization process to prepare PP having relative broad molecular weight distribution. CDIPS catalyst is advantageous to prepare low melt flow ratio PP. The tensile modulus, flexural modulus and impact strength of obtained PP is better than that of Ref. catalyst.