聚乙二醇改性PET/PBT共混体系研究

STUDY ON PET/PBT BLEND MODIFIED BY POLY(ETHYLENE GLYCOL)

本文以廉价易得的聚乙二醇(PEG)作结晶促进剂,利用WAXD、DSC研究了PET/PBT共混体系的结晶行为,并以共混体系结晶熔融峰面积计算PET和PBT各自的结晶度。结果发现,加入PEG可以使共混体系冷结晶峰温明显下降,PEG用量越大,冷结晶峰温越低,结晶速度加快;随着PEG分子量增大,当小于2000或等于2000时,冷结晶峰温随之降低,但当分子量≥6000时,冷结晶峰温随之略有升高;加入PEG,对共混体系中PET和PBT各自结晶的作用不同,二者的结晶度随PEG分子量或用量变化不同。

PET/PNT blend with poly (ethylene glycol) (PEG) as crystalline-accelerator was investigated with aid of WAXD and DSC. It was found that PEG can obviously decrease the peak temperature of PET/PUT blend for cold crystallization, and the peak temperature becomes lower and crystallization becomes faster with PEG amount. The peak temperature decreases as molecular weight of PEG increases at M(PEG)<2000, but it rises at M(PEG)>00; PEG has different function to PET and PBT crystallization, crystallization of PBT and PET rises as M(PEG) rises. However, crystallization for PBT increases and for PET decreases as PEG level adds. Generally speaking, for PET/PBT blend system, PEG is favorable to PBT crystallization but not favorable to PET crystallization.