聚苯乙烯的暗氧化及其反应机理研究

THE DARK OXIDATION OF POLYSTYRENE AND ITS MECHANISM

聚苯乙烯的暗氧化及其反应机理研究朱军民曹维孝冯新德（北京大学高分子科学与工程系北京１００８７１）关键词聚苯乙烯，异丙苯，接触电荷转移复合物（ＣＣＴ），暗氧化反应高分子材料在加工、贮存和使用的过程中，当受到大气中氧、光、热等作用时，会发生降解和交...

Cumene and other derivatives of benzene can form reversible contact charge transfer complexes (CCT) with O_2, but due to the influence of the space structure of polystyrene (PS) such as steric or electronic effect caused by the neighboring benzene ring, the O_2 CCT of PS is irreversible. High molecular weight PS(HPS) gives its maximum absorption wavelength of O_2 CCT at 278.4nm, but low molecular weight PS(LPS) at 2956nm as it has a similar structure of styrene due to a double bond at one end of its chain which results in the red shift of O_2 CCT absorption. The CCT formed between PS and O_2 has been considered as the initial state of the dark oxidation and it is proposed that PS as like the model compound cumene undergoes dark oxidation through O_2 CCT, CTC, H + transfer, free radicals in cage and the formation of hydroperoxides.