PP/LDPE共混物拉伸过程中的颈缩行为

Necking Behaviour of PP/LDPE Blends in Tensile

应用Instron材料试验机考察了室温下PP／LDPE共混物拉伸过程中的颈缩行为，以及断裂伸长率。随LDPE质量百分含量外的变化。研究发现，拉伸强度极限随着φL的增加而下降，相应的形变亦随之增大；而。对φL的依赖性，熔体指数高的PP与低的PP有所不同，反映出它们与LDPE在混容性方面的差异。

The necking behaviour of polypropylene (PP)/low density poyethylene(LDPE) blends in tensile and the relationship between elongation at break 4 and weight percentage content de of LDPE were investigated with an Instron theterial Testing Machine at room temperature. It was found that the tensile strength limit decreased and relevant deformation increased with increasing φL; and in terms of the dependence of 4 on φL, PP with high melt flow index was different to that with low melt flow index. It suggested that the difference between they and LDPE in mixing competibility was attributed to the viscosity ratio among them