丙烯聚合N高效催化剂的研究 Ⅰ.丙烯聚合反应动力学

Study on the High Efficiency N-Catalyst for Propylene Polymerization Ⅰ. A Kinetic Study of Propylene Polymerization

测定了N-催化剂体系丙烯常压淤浆聚合活性中心浓度(C_p)、链增长速度常数(k_p)、聚合物的分子量及其分布等参数,并与络合-Ⅱ型催化剂进行了比较。C_p用动力学外推法求取,分子量用凝胶渗透色谱法测定。结果表明,N-催化剂体系是一种长效体系,定向能力不受部分聚合条件变化的影响。与络合-Ⅱ型催化剂相比,该体系具有高活性的主要原因是其活性中心浓度较高。

The concentration of active centre (C_p), the chain propagation rate constant (k_p), the molecular weight(M_n)and the molecular weight distribution(M_w/M_n), etc. in the slurry polymerization of propylene at atmospheric pressure with Ncatalyst system were determined. C_p and M_n were obtained by kinetie extrapolation and GPC, respectively. It was found that the N-catalyst system was a permanently effective system and its stereo-regularity did not change with changes in polymerization conditions. Compared with complex-Ⅱtype catalyst, the main reason for N-catalyst system's high activity was that the system had higher concentration of active centre.