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Preparation of Binary and Ternary Deep Eutectic Systems
Published on: October 31, 2019
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Glass transition and mixing thermodynamics of a binary eutectic system
Wenkang Tu1, Zeming Chen, Yanqin Gao
1State Key Lab of Metastable Materials Science and Technology, and College of Materials Science and Engineering, Yanshan University, Qinhuangdao, Hebei 066004, China. Limin_Wang@ysu.edu.cn.
Physical Chemistry Chemical Physics : PCCP
|January 14, 2014
Summary
Mixing thermodynamics significantly impact glass transition temperature (Tg) in binary systems. This study quantifies this effect in benzil and m-nitroaniline, revealing deviations from ideal mixing behavior.
Area of Science:
- Physical Chemistry
- Materials Science
- Thermodynamics
Background:
- Glass transition temperature (Tg) is a critical parameter in polymer and materials science.
- Understanding the factors influencing Tg, such as mixing thermodynamics, is essential for material design.
Purpose of the Study:
- To quantitatively evaluate the contribution of mixing thermodynamics to the glass transition in a binary eutectic system.
- To investigate the deviation from ideal mixing rules for the glass transition temperature (Tg).
Main Methods:
- Microcalorimetric measurements of the enthalpy of mixing.
- Analysis of the composition dependence of the glass transition temperature (Tg).
- Application of the Gordon-Taylor and Couchman-Karasz models.
Main Results:
- Enthalpy of mixing values were small and positive (~200 J mol(-1) for equimolar mixture).
- The Tg showed large, negative deviations from the ideal mixing rule.
- Existing models explained only a small fraction of the observed Tg deviation.
Conclusions:
- Mixing thermodynamics play a quantitatively significant role in the glass transition of miscible systems.
- The study highlights limitations of current models in fully explaining Tg behavior based on mixing thermodynamics.
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