【摘要】 综合宏观性能和微观结构两方面研究聚对苯二甲酸乙二醇酯(PET)的水热老化过程,研究水在老化不同阶段所起的作用,从而揭示PET的水热老化机理。结果表明:PET老化过程中,不仅存在水解反应引起的化学结构变化,而且存在水热共同作用导致的结晶度变化及结构松弛现象。各因素自始至终都在起作用,不同阶段起主导作用的因素不同,老化初期结晶度对材料性能的影响最大,而在老化后期,水降解起主导作用。更多还原

【Abstract】 Hydrothermal ageing of poly(ethylene terephthalate)(PET)and the effect of water during the different stages of ageing process had been investigated macroscopically and microscopically.The hydrothermal ageing mechanism was discussed accordingly.The results showed that there were changes of two aspects:chemical changes owing to hydrolysis,and physical changes arising from re-crystallization and structure relaxation caused by water and temperature.These factors had effect on the properties throughout the whole ageing process,and different factors played the dominant role at the different stages.In the early stage of aging,re-crystallinization was the key factor and then hydrolysis was the predominant reaction.更多还原