PET/PC共混物配比对其高压结晶行为的影响

利用SEM及W AXD等测试手段研究了配比对PET/PC共混物高压结晶行为的影响。SEM观察表明,随PC比例的增加,共混物高压下主要结晶形态以伸直链晶体,生长成熟的立体开放球晶,大尺寸球晶的方式变化。拟合分峰法和W arren-A verbach傅氏分析法的计算结果表明,随PC含量的增加,高压结晶共混物的结晶度降低,PET的平均晶粒尺寸总体呈减小趋势,晶粒尺寸分布则变窄,而晶格畸变平均值在一定PC比例范围内达到极大值。

EFFECT OF COMPOUNDING RATIO ON HIGH-PRESSURE CRYSTALLIZATION BEHAVIOURS OF PET/PC BLENDS

Compounding ratio effect on high-pressure crystallization behaviours of PET/PC blends was investigated by SEM and WAXD measurements.SEM observation revealed that three kinds of crystal morphology formed orderly with the increase of PC ratio,i.e.extended-chain crystal,grownup stereo-open spherulite and large size spherulite.Total crystallinity of various samples obtained from WAXD results showed a decreasing tendency with the increasing of PC ratio.This is explained by the crystallization rate difference between PC and PET.Mean crystallite size and mean micro-strain of PET in these samples was computed according to W-A/FT method.The results demonstrated a change of decreasing for mean size and narrowing for distribution with PC ratio increasing.This is interpreted as the inhibition of PC for the crystallization of PC droplets with finer dispersion that did not result in heterogeneity.The results also showed mean micro-strain attained a maximum value for some PC ratio due to different miscibility for various PET/PC blend crystallized under high-pressure.