【摘要】 采用等速升温DSC方法对单轴取向聚对苯二甲酸乙二酯 (PET)的结晶过程进行了研究 ,发现单轴取向PET的冷结晶峰表现为多重结晶峰 .等温DSC方法的研究结果进一步证实结晶重峰的存在 .为此 ,本文提出了一种依据非等温DSC曲线解析高聚物结晶动力学参数的新方法 .对单轴取向PET的研究结果表明 ,与其他方法相比较 ,由新方法计算出的理论曲线与实验数据能更好地吻合 .单轴取向PET的总的结晶过程由三个子结晶过程组成 .根据不同拉伸比 ,各个子过程的Avrami指数和质量分数的变化 ,对结晶机理进行了解释 .与各向同性PET样品相比 ,单轴取向PET在低温部分的结晶速率明显增快更多还原

【Abstract】 The crystallization process of uniaxially oriented poly(ethylene terephthalate)(PET)was investigated by using DSC with a constant heating rate.The cold crystallization thermograms of uniaxially oriented PET exhibit multiple-overlapping peaks.This phenomenon was also confirmed by the isothermal DSC studies.A new method was proposed to obtain the crystallization kinetic parameters of polymers from the complicated DSC curves.The result indicated that the theoretical curve calculated from the new method shows a better agreement with the experimental data than that from the other methods.The crystallization process of uniaxially oriented PET was analyzed by using a model that involved three different crystallization mechanisms depending on different temperature ranges.The whole crystallization process of uniaxially oriented PET consists of three sub-processes.Crystallization mechanism was explained based on the change of the Avrami exponent and mass fraction of every sub-process with draw ratio.更多还原