Enthalpy and Dielectric Relaxations of Triacetin in the Vicinity of Glass Transition
Enthalpy and Dielectric Relaxations of Triacetin in the Vicinity of Glass Transition
复制标题
三醋精在玻璃化转变附近的焓和介电弛豫
DOI：
10.3866/pku.whxb201206061
复制
发表时间：
2012
期刊：
影响因子：
--
通讯作者：
Li-Min Wang
中科院分区：
文献类型：
--
作者：
Zeming Chen;Dongyang Bi;Li-Min Wang
为了理解实验观察，确定的焓和介电弛豫的动态参数可能会有所不同，在脆弱的玻璃形成的分子液体，一个脆弱的分子液体，三醋精，被选择为两个弛豫动力学的研究。重点研究了两种弛豫过程的非Arrhenius和非指数特征，发现由两种弛豫测量方法确定的动力学脆性和非指数参数非常相似。实验结果表明，在两个弛豫涉及的分子运动的相关程度取决于分子的灵活性。讨论了动力学参数对玻璃形成液体中分子结构的依赖关系。
To understand the experimental observation that the dynamic parameters determined for enthalpy and dielectric relaxation might differ in fragile glass-forming molecular liquids, a fragile molecular liquid, triacetin, was chosen for the study of the two relaxation dynamics. The non-Arrhenius and nonexponential characters were focused, and the kinetic fragility and non-exponential parameter determined from the two relaxation measurements were found to be remarkably similar. Experimental results indicate that the degree of correlation in the molecular motions involved in the two relaxations depends on molecular flexibility. The dependence of the dynamic parameters on molecular structures in the glass forming liquids is discussed.