木糖醇玻璃焓松弛动力学的现象学研究  

A phenomenological study of enthalpy relaxation dynamics of xylitol glass

作　　者：崔培培[1] 高才[1] 杨锁[1] 叶斌[1] 唐景春[1] 倪宜华[1] 

机构地区：[1]合肥工业大学机械与汽车工程学院,安徽合肥230009

出　　处：《合肥工业大学学报（自然科学版）》2011年第10期1545-1550,共6页Journal of Hefei University of Technology：Natural Science

基　　金：国家自然科学基金资助项目(20803016);安徽省自然科学基金资助项目(070414163)

摘　　要：为了比较3种基于Adam-Gibbs(AG)理论的焓松弛现象学模型的预测力,文章利用差示扫描量热仪(DSC)分析木糖醇玻璃体系的焓松弛行为,在10 K/min的升温速率下测定经历不同降温速率(0.5～20K/min)的木糖醇在玻璃化转变温度(Tg)前后的比定压热容(cp),并运用Adam-Gibbs-Vogel(AGV)、Gmez Ribelles(GR)和Hutchinson(H)3种现象学模型对实验数据进行曲线拟合。结果表明,3种模型均能很好地重现经历不同降温速率木糖醇玻璃体系实验升温cp曲线,但模型预测的Adam-Gibbs温度(T2)普遍小于由其他实验方法分析(如Williams-Landel-Ferry(WLF)方程分析、介电松弛法等)得到的T2值,H模型对实验数据的预测力强于AGV和GR模型。In order to compare the predictive power of three kinds of enthalpy relaxation phenomenological models based on Adam-Gibbs（AG） theory, the enthalpy relaxation behavior of xylitol glass system was analyzed by differential scanning calorimetry（DSC）. A series of specific heat capacity （cp） near the glass transition temperature（Tg） were measured while heating at a rate of 10 K/min as the cooling rate varied between 0. 5 K/min and 20 K/min. Three phenomenological models of Adam- Gibbs-Vogel（AGV）, Gmez Ribelles（GR） and Hutchinson（H） were used in the curve fitting of exper- imental data. The results show that all of the three models are able to reproduce the experimental cp curves of xylitol,but the values of Adam-Gibbs temperature（T2） predicted by these models are lower than those by other approaches, such as Williams-Landel-Ferry（WLF） equation analysis and dielectric relaxation analysis. It can be concluded that H model works better than other two models in the presented study.

关 键 词：木糖醇 现象学模型 焓松弛 差示扫描量热仪 

分 类 号：O642.3[理学—物理化学] O645.16[理学—化学]