摘要
本文通过对TiCl_3-Al(C_2H_5)_3聚合1-辛烯产物的双峰型分子量分布曲线用Schulz函数进行拟合、分峰处理,发现这种双峰型分布中的高分子量峰部分由一种活性中心生成,低分子量峰部分则由至少两种活性中心生成.将不同转化率时聚辛烯的分子量分布分峰拟合数据与聚合速率、活性中心数等测定数据相结合,得到了高分子量和低分子量两部分产物相应的活性中心上各自的动力学参数(增长速率常数、活性中心数、链转移常数等)及各自的聚合速率曲线,从而证实了多种活性中心的存在、它们催化特性的差异及与聚合物分子量分布增宽的关系.
The bimodal molecular weight distribution (MWD) of polyoctene-1 synthesized with TiCl3-Al(C2H5)3 are fitted with the Schulz-Flory 'most probable' distribution and seperated into two peaks. It was found that the peak with higher molecular weight is formed on one kind of active center, while the peak with lower molecular weight is produced by at least two kinds of active center, Combining the results of MWD fitting with data of the polymerization rate and the number of active centers, a series of kinetic parameters (preparation rate constant, number of active centers, chain transfer constants, etc.)of different kinds of active centers are determined. The results highlighted the plurality of active centers, the differences in catalytical characteristics between these centers and the origin of the broadened bimodal MWD.
出处
《高分子学报》
SCIE
CAS
CSCD
北大核心
1992年第5期577-584,共8页
Acta Polymerica Sinica
基金
国家自然科学基金
关键词
活性中心
Z-N聚合
聚1-辛烯
Ziegler-Natta polymeriza ion, Active center, Molecular weight disttribution
