聚β-羟基丁酸酯/聚氧化乙烯共混体系力学性能研究

本文详细研究了可完全生物降解的聚 β 羟基丁酸酯 (PHB)与水溶性聚氧化乙烯 (PEO)两元共混体系的拉伸力学性能 .讨论了PEO分子量、共混组成及热处理条件对共混体系力学性能的影响 .其中 ,PHB与超高分子量PEO(重均分子量 5× 10 6)共混 ,两组分力学上具有相容性 ,共混物的拉伸强度、断裂伸长率及模量都有明显的正的协同效应 .共混改性效果显著PHB的力学性能得到很大改善 ,尤其PHB的脆性缺陷 .并且 ,共混物在经过适当温度退火处理之后 ,共混物性能还可进一步改善

Advanced research work on radiation cross-linking of polymers in CIAC

Recent research carried out at the Chinese Institute of Applied Chemistry has contributed significantly to the understanding of the radiation chemistry of polymers. High energy radiation has been successfully used to cross-link fluoropolymers and polyimides. Here chain flexibility has been shown to play an important role, and T-type structures were found to exist in the cross-linked fluoropolymers. A modified Charlesby-Pinner equation, based upon the importance of chain flexibility, was developed to account for the sol-radiation dose relationship in systems of this type. An XPS method has been developed to measure the cross-linking yields in aromatic polymers and fluoropolymers, based upon the dose dependence of the aromatic shake-up peaks and the F/C ratios, respectively. Methods for radiation cross-linking degrading polymers in polymer blends have also been developed, as have methods for improving the radiation resistance of polymers through radiation cross-linking.