半晶PBT在室温存放时的聚态结构变化

用DSC观察了不同冷却条件半晶PBT样品在室温存放时所发生的聚态结构变化。实验表明,在310～325K出现的热焓松弛峰的峰高和峰温随存放时间的变化与冷却条件有关。该峰表征试样中“硬无定形部分”的松弛。本文定量地描述了它的峰高与峰温对存放时间的依赖关系。发现水对松弛过程和随之发生的冷结晶有一定程度的抑制。室温存放过程中,晶态结构缺陷有,所减少并少量新的亚稳态晶体形成。

STRUCTURAL CHANGES OF SEMICRYSTALLINE PBT DURING STORING AT ROOM TEMPERATURE

Structral changes of semicrystalline poly (buthlene terephthalate) samples prepared with different cooling conditions during storing at room temperature were observed by using DSC. The experimental results indicated that the changes of height and temperature of the small endothermal peak appearing at 310-325K with storing time is relative to the cooling conditions. The peak is attributed to the relaxation of "rigid-amorphous fractions" in samples. This paper describes quanti- tatively that the peak height and the peak temperature is relative to storing time. It is found that water inhibit the processor relaxation and cold crystallization. During storing at room temperature, crystalline defects are decreased slightly and small quantity of crystals were formed.