4，4＇－二苯醚二甲酸改性PET的热性能研究

STUDY ON THE THERMAL PROPERTY OF POLY (ETHYLENE TEREPHTHALATE) MODIFIED WITH 4,4'-OXYBIS (BENZOIC ACID)

采用示差扫描量热和热重分析的方法对合成的不同４，４＇－二苯醚二甲酸（ＯＢＢＡ）含量的共聚酯的热性能进行了研究。结果发现共聚酯的熔点和热结晶温度与ＰＥＴ相比有所降低；而冷结晶温度则升高。随着ＯＢＢＡ添加量的增加，在恒温热重分析中热失重速率常数减小；在升温热重分析中，热失重活化能则增加。所有的实验结果皆表明，芳族醚键的引入对提高共聚酯的热性能有重要作用。

The thermal property of PET modified with4,4'-oxybis (benzoic acid) (OBBA) was studied by using differential scanning calorimetry, isothermal and dynamic thermogravimetric analysis. The results showed that the melting temperature and hot crystallization temperature of copolyester were lower while cold crystallization temperatures were higher than the related values of pure PET.It was found that the thermogravimetic rate constants k of copolyester decreased in the isothermal thermogravimetic analysis and the thermogravitric activation energy Ea of copolyester increased with increasing amount of OBBA in the dynamic thermogravimetry analysis.All the above experimental results indicated that the contribution of the ether bond of 4,4 '-oxydiphenylene group to the main chain lead to an important effect on the themal property of this kind of copolyester.