如何区分非指数性和非线性在玻璃成型材料的同热结构放松中
1Department of Physical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentská 573, Pardubice 532 10, Czech Republic.
The journal of physical chemistry. B
|August 8, 2024
概括
玻璃成型材料中的结构松表现出非指数性和非线性,可以使用温度跳跃实验来分离. 一种新方法估计了材料中非指数性 (ß) 和非线性 (σ) 的参数.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 玻璃成型材料中的结构松以非指数性和非线性为特征.
- 这些属性往往相互交织,难以分离.
- 了解这些特征对于预测物质随时间推移的行为至关重要.
研究的目的:
- 在结构放松中分离和量化非指数性和非线性.
- 提出一种简单的方法来估计与这些现象相关的材料参数.
- 分析温度跳跃后接近平衡的不对称性.
主要方法:
- 使用相同大小的温度下跳和上跳实验.
- 使用稳定期 (log(t_m/t_0)) 量化同热结构放松.
- 为现象学模型制定材料参数σ.
主要成果:
- 提出了一种方法,将放松描述为非指数性 (1.181/ß) 和非线性 ((σ/2.303) ΔT) 项的和或差.
- 材料参数σ量化了放松时间变化与结构变化的变化.
- 该方法在聚合物和其他玻璃制成物的实验和计算数据上进行了测试.
结论:
- 温度跳跃实验提供了一种方法来区分结构放松中的非指数性和非线性.
- 介绍了一种用于估计关键材料参数 (ß 和 σ) 的简单方法.
- 这种方法有助于理解用于材料设计和老化评估的结构松动动力学.
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