相对分子质量分布对双峰聚乙烯薄膜树脂等温结晶动力学的影响

研究了2种双峰聚乙烯薄膜树脂（9455F1 W和9455F1 100）的等温结晶动力学行为，并讨论了相对分子质量分布的双峰相对含量对结晶过程的影响。结果表明，2种样品都呈现双峰分布的特征，且其相对分子质量相差不大，但高/低相对分子质量级分含量不同；其中，9455F1 W样品的高相对分子质量级分的相对含量大，9455F1 100样品的低相对分子质量级分的相对含量大；随低相对分子质量级分含量的增加，样品的结晶速率常数增大，半结晶时间减小，结晶速率增大。

Effect of Molecular Weight Distribution on Isothermal Crystallization Kinetics of Bimodal Polyethylene Resin for Films

Isothermal crystallization kinetics of two types of bimodal polyethylene resins (9455F1-W and 9455F1-100) for films was studied in this work, and the effect of bimodal molecular weight distribution on their crystallization behavior was discussed. The results from gel permeation chromatography measurements indicated that these two types of resins exhibited a bimodal distribution feature. They had a similar molecular weight but different fractions in high- and low-molecular-weight macromolecules. 9455F1-W sample had a higher fraction in-molecular-weight macromolecules than 9455F1-100 sample. Isothermal crystallization investigation indicated that the crystallization rate constant increased with an increase in the fraction of low-molecular-weight macromolecules, and however the half crystallization time decreased, suggesting an increase in crystallization rate.