摘要
分别采用DQ型和BC-MS型Ziegler-Natta催化剂催化丙烯本体聚合,助催化剂为三乙基铝(TEAL)与三异丁基铝(TiBA)的混合物,外给电子体为二苯基二甲氧基硅烷,氢气作相对分子质量调节剂,反应釜内的装料系数为70%。首先在20℃条件下进行预聚合,预聚合结束后迅速升温至70℃聚合。研究了TEAL/TiBA混合助催化剂对聚丙烯(PP)等规指数、熔体流动速率(MFR)和力学性能的影响。结果表明:随着助催化剂中TiBA用量的增加,所制PP的等规指数降低,MFR呈降低趋势。与BC-MS型催化剂相比,用DQ型催化剂制备的PP的弯曲强度和弯曲模量总体上较低,简支梁缺口冲击强度相对较高。
In this paper, two kinds of commercialized Ziegler-Natta catalysts, namely DQ catalyst and BC-MS catalyst, were used to catalyze propylene bulk polymerization with triethylaluminum(TEAL) and triisobutylal-uminium (TiBA) mixtures as cocatalysts, diphenyldimethoxysilane as an external donor and hydrogen as a relative molecular mass regulator, and the charge coefficient of the autoclave was 70%. The prepolymerization of propylene was carried out at 20 ℃,and the temperature was rapidly elevated to 70 ℃ after prepolymerization. The effects of TEAL/TiBA mixed cocatalyst on isotacticity, melt flow rate(MFR) and mechanical properties of the resultant polypropylene(PP) were studied. The results indicate that both the isotacticity and the MFR of the PP tend to decrease as the amount of TiBA in TEAL/TiBA mixed cocatalyst increases. Compared with BC-MS catalyst, the PP prepared with DQ catalyst has lower flexural strength and flexural modulus but higher charpy notched impact strength.
出处
《合成树脂及塑料》
CAS
北大核心
2014年第5期6-9,共4页
China Synthetic Resin and Plastics
基金
国家重点基础研究发展规划项目(2011CB606001)
浙江省公益技术研究工业项目(2012C21056)