PVA/HDPE/HDPE-g-MAH共混物的相形貌与动态流变性能

Phase Morphology and Dynamic Rheological Properties of PVA/HDPE/HDPE-g-MAH Blends

采用熔融共混法制备了聚乙烯醇（PVA）/高密度聚乙烯（HDPE）共混物,引入马来酸酐接枝高密度聚乙烯（HDPE-g-MAH）对体系进行增容。利用SEM、小振幅震荡剪切、溶剂提取、拉伸测试考察组成和增容剂含量对共混物相形貌、动态流变性质、相连续性和力学性能的影响。结果表明,当HDPE质量分数达到20%~30%时,PVA/HDPE/HDPE-g-MAH共混物呈现接近共连续的结构;储能模量-频率图中观察到较为明显的第二平台;PVA相的连续度达到98%;共混物的断裂伸长率由5%显著提高到25%左右。另外,当HDPE-g-MAH的含量增大时,共混物的相界面变得模糊,力学性能也随之提高。

Polyvinyl alcohol （PVA）/high density polyethylene （HDPE） blends were prepared via melt blending with high density polyethylene-gra/z-maleic anhydride（HDPE-g-MAH） added to the blends for compatibilization. Effects of blend composition and content of compatibilizer on the phase morphology, dynamic rheological properties, phase continuity and mechanical properties of the blends were investigated using scanning electron microscope, small amplitude oscillatory shear, solvent extraction and tensile measurement. Results indicated that a relatively co-continuous structure was generated when the mass fraction of HDPE was 20%-30 %, in which case a second plateau was observed from the storage versus frequency curves. The continuity of PVA phase calculated by solvent extraction reached approximately 98%. The elongation at break also experienced a significant increase from 5 % to 25%. In addition, the phase interface of PVA/HDPE/HDPE-g-MAH blends blurred as the HDPE-g-MAH content increased, meanwhile the mechanical performance improved.