玻璃态PS焓松弛β参数的热历史依赖性

doi:10.3969/j.issn.1000-1565.2011.06.012

摘要/Abstract

摘要： 用TNM模型研究了PS的焓松弛,将模型参数△h,x和lnA作为材料常数,假定β参数随热处理条件变化,提出了新的参数优化方法:由极限假想温度Tf'求取△h；由Tf '和峰值温度Tmax求取x和lnA,不同热处理条件下的β值由对归一化比热CNp数据进行拟合得到.Tf',Tmax和CNp的理论计算值都与实验结果十分接近,得到的参数具有规律性,β随热处理条件变化,当降温速率从100 K/min降到0.1 K/min时,β从0.498降到0.341,在363.15 K下恒温老化,随老化时间延长β呈现极大值0.504,从结构松弛的角度对上述结果进行了解释.

关键词: PS, β参数, 玻璃化转变, 焓松弛, 热历史

中图分类号:

O631.5

李丽霞,赵冬梅,范留彬,刘国栋. 玻璃态PS焓松弛β参数的热历史依赖性[J]. 河北大学学报(自然科学版), 2011, 31(6): 617-622.

LI Li-xia,ZHAO Dong-mei,FAN Liu-bin,LIU Guo-dong. Thermal History Dependence of Kohlrausch Parameter β in Enthalpy Relaxation of Glassy Polystyrene[J]. Journal of Hebei University (Natural Science Edition), 2011, 31(6): 617-622.

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