摩尔质量分布对宽峰聚乙烯动态流变行为的影响

The Influence of Molecular Weight Distribution on the Dynamical Rheology Behavior of BPE

通过熔融共混一种双峰聚乙烯(PE100)和单峰聚乙烯(PE5000S)制备了一系列摩尔质量连续变化的宽峰聚乙烯,研究了摩尔质量分布对它们动态流变行为的影响。结果表明,PE100和PE5000S具有良好的相容性,没有发现明显的相分离现象;随着多分散性逐渐变窄,共混物的零剪切黏度下降,储能模量和损耗模量均有减小,并表现出交点模量Gx,它随着Mw/Mn的减小略有增加,而交点频率有较大升高。

In this paper, a series of bimodal/broad polyethylenes （BPE） with different molecular weight distribution were prepared by melt blending a bimodal PE and a unimodal PE, and the dynamical rheology behaviors of them were studied. The results showed no obvious phase separation had been found in the experiments for all samples, indicating the good compatibility of the PE100 and 500S, with the decrease of PDI （M w/Mn ） of the blends, the zero shear viscosity, storage modulus and loss modulus of the blend decreased to some extent, and the module of intersection GX had a slight increase with the Mw;Mn increased, while the frequency at Gx increased a lot.