固相缩聚对聚酯切片热性能和结晶行为的影响

Influence of Solid-phase Polycondensation on Thermal and Crystallization Properties of Polyester Chips

用差示扫描量热仪(DSC)和热重分析仪分别对普通聚酯切片和通过固相缩聚增黏的聚酯切片进行了热性能和结晶行为的研究。结果表明,固相缩聚增黏的聚酯切片的DSC第一次升温曲线上观察不到结晶放热峰,说明固相缩聚使聚酯相对分子质量增大的同时,也使其得到充分结晶;固相缩聚增黏聚酯切片的熔点升高;此外,固相缩聚增黏聚酯切片的结晶度较低、结晶尺寸较小、结晶速率较小,而热稳定性优于普通聚酯切片。

The thermal and crystallization properties of ordinary polyester （PET I） and solid-phase polycondensation thickened polyester chips （PET II） were analyzed by DSC and thermal gravimetric analysis. On the first heating of DSC, no crystallization endothermic peak was observed on PET II, indicative that the solid-phase polycondensation not only increased the molecular weight, but also completed the crystallization. The melting point of PET II increased. The crystallinity of PET II was lower, the size of PET II was smaller, the crystallization rate of PET II was smaller, compared with PET I. The thermal stability of PET II was better than PET I.