论文部分内容阅读
通过共缩聚反应合成了不同ＰＥＧ分子量的ＰＥＴ－ＰＥＧ共聚物，其中ＰＥＧ含量占７％（相对于ＤＭＴ质量比），以ＤＳＣ、解偏振光法测定了共聚物的结晶性能和结晶速度。结果表明ＰＥＧ的引入能有效地增加分子链柔性，改善结晶性能，尤其ＰＥＧ分子量为４０００时，结晶速度得以大大提高，温度为１１０℃时，ＰＥＴ－ＰＥＧ４０００结晶速度仅１ｍｉｎ，电镜分析表明共聚物中的ＰＥＧ分子量提高有助于分子链的有序性提高，从而加速结晶，但同时也会引起分子链缠结，从Ｘ衍射图谱上，可以看出ＰＥＧ在结晶过程中并不进入ＰＥＴ晶格中，它只起到诱导结晶的作用。
The PET-PEG copolymers with different molecular weights of PEG were synthesized by copolycondensation. The content of PEG accounted for 7% (relative to DMT mass ratio). The crystallization and crystallization rate of the copolymers were determined by DSC and depolarization methods. The results show that the introduction of PEG can effectively increase the flexibility of the molecular chain and improve the crystallization performance. Especially when the PEG molecular weight is 4000, the crystallization speed is greatly increased. The crystallization speed of PET-PEG4000 is only 1 min at 110 ℃. PEG molecular weight helps to improve the orderliness of the molecular chain to accelerate crystallization, but also cause molecular chain entanglement, it can be seen from the X-ray diffraction pattern that PEG does not enter the PET lattice during crystallization , It only plays the role of inducing crystallization.