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Published on: January 26, 2016
Dielectric relaxation dynamics in glass-forming mixtures of propanediol isomers
Li-Min Wang1, Yue Zhao, Mingdao Sun
1State Key Laboratory of Metastable Materials Science and Technology, and College of Materials Science and Engineering, Yanshan University, Qinhuangdao, Hebei 066004, China. limin_wang@ysu.edu.cn
Abstract:
The relaxation dynamics of 1,2-propanediol-1,3-propanediol mixtures is studied in supercooled liquid regions across a wide composition range. The composition dependences of liquid fragility and nonexponential parameter β(KWW) are presented in the hydrogen-bonded mixtures with ideal mixing. The fragility index and glass transition temperature are shown to develop inversely with β(KWW), in analogy to the dynamic behaviors in mixtures of van der Waals liquids. Negative mixing effects on liquid fragility and β(KWW) are observed, and the strongest dependence of β(KWW on relaxation dynamics is revealed at the equimolar concentration. The glass formation in isomeric liquids is also addressed.
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