高分子分子量、分子量分布与熔体指数(MI)关系的研究(Ⅱ)──聚丙烯的分子量、分子量分布及熔体指数(MI)的实验考察

Study on the Reationship between Molecular Weight,Molecular Weight Distribution and Melt Flow Index of Polymers(Ⅱ)Experimental Investigation on the Molecular Weight,Molecular Weight Distribution and Melt Flow Index(MI)of Polypropylene

本文采用凝胶渗透色谱法（ＧＰＣ：ＷＡＴＥＲＳ－１５０Ｃ），对不同分子量、分子量分布和熔体指数的聚丙烯进行了测定，测定ＭＩ的样品近５０种，为验证本文第Ｉ部分提出的理论方程提供了相当充分的基础数据。从中发现齐格勒一纳塔催化剂的工业级聚丙烯的熔体指数范围可以很宽（０．５—１６ｇ／１０ｍｉｎ）。而重均分子量的范围大体上为２．５×１０５一３．５×１０５，数均分子量范围为２×１０４一６×１０４，从而使分子量分布分散系数（Ｍｗ／Ｍｎ）范围为４—１６。

In the experiment.fifty kinds of samples of PP with different molecular weight,molecular weight distribution and melt flow index were determined using Gel permeation chromatography method(GPC:WATERS-150),it provid-ed ample basis data for verifying the theoretical equation presented in the part I of this paper.From experimental results it was found that the melt flow index range of industrial grade PP polymerized by Ziegler-Natta cata-lyst maybe much wider,but the range of weight average molecular weight is about 2.5×105-3.5×105;and the range of number average molecular weight is adout 2×104-6×104. Thus,the range of molecular weight distribution coeffi-cient Mw／Mn is 4-16