PET/LCP反应性共混酯交换动力学研究

Study on Transesterification Kinetics of PET/LCP Reactive Blends

采用1 HNMR对聚对苯二甲酸乙二酯 (PET)与液晶共聚酯 (LCP)在少量扩链剂双 (2 唑啉 )BOZ存在下反应性共混的酯交换动力学进行了研究。设反应性共混的酯交换反应是二级可逆 ,则在 2 70、2 80、2 90℃下的酯交换反应速率常数分别为 1.5 5×10 - 2 、2 .2 0× 10 - 2 、3 .0 1× 10 - 2 (min- 1 ) ,均比不含扩链剂的体系的酯交换速率快 ;取得酯交换的活化能为 84.4(kJ·mol- 1 )较一般的PET/LCP的酯交换反应活化能低 ,这些均表明BOZ的加入对于PET/LCP的酯交换反应具有明显的促进作用。

The transesterification kinetics of Poly(ethylene terephthalate) (PET)/Copoly(oxybenzoate p terephthalate) (LCP) (70/30 by weight) in the presence of small amount of bis(2 oxazoline)(BOZ) as chain extender were studied by using 1 HNMR . The kinetic data was treated as a second order reversible reactions, it was found that the rate constants of transesterification at 270?280?290℃ are 1.55×10 -2 ?2.20×10 -2 ? 3.01×10 -2 (min -1 ) , respectively, the value at 280℃ was higher than the blend without addition of BOZ at 280℃, 1.26×10 -2 (min -1 ), and the activation energy of PET/LCP transesterification is 84.4 kJ·mol -1 .