在二硫化玻璃制剂中的温度和速率依赖的断裂
Zhaoqiang Song1, Gaoweiang Dong2, Franck J Vernerey3
1Department of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, California 92093, United States.
ACS macro letters
|July 25, 2024
概括
硫化二氧化物玻璃制剂的断裂取决于速率,并不能完全通过时间温度叠加来解释. 分子环缺陷,随着温度的增加,驱动这些骨折行为.
科学领域:
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
- 类风病学 类风病学 类风病学
背景情况:
- 双硫化玻璃体表现出复杂的,取决于速度的骨折行为.
- 现有的模型,如时间-温度叠加,不能完全捕捉这些行为.
- 假设分子网络缺陷会影响材料属性.
研究的目的:
- 调查分子缺陷在二硫化玻璃制剂的温度和速率依赖的断裂中的作用.
- 为了识别玻璃体网络中的主要动态缺陷.
- 为了将缺陷度与观察到的断裂现象相关联.
主要方法:
- 利用小振幅振荡剪切来探测材料动态.
- 量化了EPS25二硫化物玻璃制剂中循环缺陷的比例.
- 多种温度条件,观察缺陷度和机械反应的变化.
主要成果:
- 确定循环缺陷是网络中关键的动态分子缺陷.
- 在高温下观察到更高的循环缺陷度.
- 建立了温度依赖的断裂行为和循环缺陷数量之间的直接联系.
结论:
- 硫化二氧化玻璃剂的温度依赖的断裂行为主要由循环缺陷的温度依赖群体控制.
- 分子网络拓学,特别是循环缺陷,在玻璃体力学中发挥着关键作用.
- 这一发现为了解玻璃层骨折提供了超越传统时间温度叠加的新视角.
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