PET/LCP反应性共混物的非等温结晶动力学

采用DSC方法研究了聚对苯二甲酸乙二酯 (PET)和热致性液晶共聚酯 6 0PHB PET (LCP)体系在少量扩链剂双 (2 唑啉 ) (BOZ)存在下形成的反应性共混物的非等温结晶动力学 .结果表明反应性共混物的Avrami指数均在 3 0～ 4 5之间 ,BOZ的加入使反应共混物中PET组分的结晶速率降低 ;表明BOZ对酯交换的促进作用 ,使所生成的共聚酯中PET嵌段的数均序列长度变短 ,而使结晶在某种程度上较为困难 ,但对体系的成核和结晶生长机理无明显影响 .结果还表明 ,随冷却速率的增大结晶峰向低温方向移动

NON-ISOTHERMAL CRYSTALLIZATION KINETICS OF PET/LCP REACTIVE BLENDS

The non\|isothermal crystallization kinetics of reactive blends of poly(ethylene terephthalate) (PET)/copoly(oxybenzoate\| p \|terephthalate) at molar ratio 60/40 (LCP) (70/30 by weight) with addition of bis(2\|oxazoline)(BOZ) was studied by using differential scanning calorimetry (DSC).PET and LCP were blended at 280℃ with 1.5?wt% BOZ in a twin extruder for 5?min or 10?min and then put into ice water bath, respectively.The DSC results show that the Avrami exponent of the PET/LCP reactive blends is in a range of 3.0 to 4.5,which is different from the results of isothermal crystallization of PET/LCP,and the crystallization rate increases with increasing cooling rate.BOZ could promote the transesterification between PET and LCP,resulting in a decrease of the number average sequence length of PET.Therefore,It is demonstrated that,compared to the blends without addition of BOZ,the crystallization rate of the PET in the reactive blends with BOZ decreases,and the crystallinity decreases,too.The peek temperature of crystallization of reactive blends shifts to lower temperature,but the crystallization mechanism of the reactive blends isn't affected by bis(2\|oxazoline) significantly.