State Key Laboratory of Optoelectronic Materials and Technologies and School of Physics and Engineering, Sun Yat-sen University (Zhongshan), Guangzhou, 510275, China.
J Chem Phys. 2011 Mar 21;134(11):114510. doi: 10.1063/1.3564919.
By measuring the dependences of the temperature-dependent primary ("alpha") dielectric relaxation time behavior on the temperature scanning rate for the glass-forming glycerol, we study the scaling of hysteresis at the glass transition in glycerol. Based on the Vogel-Fulcher-Tammann (VFT) expression and the Angell's fragility concept, notable correlations of the systematic kinetic fragility, and of the hysteresis effect in the vitrification∕fusion "alpha"-relaxation process of glycerol, with the temperature scanning rate, were reasonably analyzed and discussed. It was observed that the kinetic fragility m and the apparent glass-transition temperature hysteresis width ΔT(g)(a), respectively, scaled the temperature scanning rate q as m ≈ α(m)q(-γ) and ΔT(g)(a) ≈ A(0) + αq(β), at which the exponents, γ and β, were suggested to be characteristic of the resistance to the structure change or fragility change of the system during the glass transition. The observed scaling laws are quite similar to the scaling power law for the thermal hysteresis in the first-order phase transition (FOPT) of solids, providing a significant insight into the hysteresis effect in the glass transition of the glass-forming liquids.
通过测量玻璃形成甘油的温度相关主（“α”）介电弛豫时间行为对温度扫描速率的依赖性，我们研究了甘油玻璃化转变处滞后的标度。基于 Vogel-Fulcher-Tammann（VFT）表达式和 Angell 的脆弱性概念，对甘油的玻璃化/熔融“α”弛豫过程中的系统动力学脆弱性和滞后效应进行了合理的分析和讨论。观察到动力学脆性 m 和明显的玻璃化转变滞后宽度ΔT(g)(a)分别以 m ≈ α(m)q(-γ)和ΔT(g)(a) ≈ A(0) + αq(β)的方式对温度扫描速率 q 进行标度，其中指数γ和β被认为是系统在玻璃化转变过程中抵抗结构变化或脆性变化的特征。观察到的标度规律与固体一级相变（FOPT）中的热滞后的标度幂律非常相似，为玻璃形成液体的玻璃化转变中的滞后效应提供了重要的见解。
