β晶型聚丙烯塑性形变过程中的形态变化

β晶型聚丙烯塑性形变过程中的形态变化沈静姝，任宏燕，况勋（中国科学院化学研究所高分子物理开放实验室，北京，１０００８０）史观一（中国科学院上海有机所，上海，２０００３２）关键词β晶型聚丙烯，塑性形变，形态全同立构聚丙烯的分子链都是３；螺旋链，但其晶体...     

非晶聚对苯二甲酸乙二醇酯薄片在低温退火过程中的声发射现象

Acoustic emission during sub-Tg annealing fort amorphous polyethylene terephthalate (PET) sheet quenched from melt has been observed. The mechanical properties, texture and glass transition of annealed specimens have been studied. It is shown that some of PET chains change from non-equilibrium state to equilibrium state during sub-Tg annealing, which leads to stress concentration in specimen. When the level of internal stress approaches to the limit, the acoustic waves are emitted due to sudden releasing of stress and the micro-defects are for-med. This is one of the important reasons,the causes the loss of mechanical properties to an-nealed specimens.     

非晶聚对苯二甲酸乙二醇酯薄片在低温退火过程中的声发射现象

从熔体淬火得到的聚对苯二甲酸乙二醇酯(PET)薄片在室温下呈非晶玻璃态,已经证明这是一种非平衡态。很多文献曾报道,在T_g以下对它进行退火处理后虽然观察不到明显的结晶,但是它的延伸性能及抗冲性能会迅速变坏。不少文献的实验表明这退火过程是试样的分子链从非平衡态转变到更