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半晶聚合物中拉伸诱导的固态到固态相变:晶体滑动的关键作用
Xiaolu Sun1, Mengzhe Han1, Jian Song1
1State Key Laboratory of Chemical Engineering and Low-Carbon Technology, Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310058, China.
The journal of physical chemistry letters
|December 1, 2025
概括
晶体学滑动驱动半晶体聚合物的固体到固体相位过渡,如转-1,4-聚乙烯 (tPBD). 这种机制是了解在中间温度下拉伸过程中的结构变化的关键.
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
- 晶体学 晶体学是指结晶学.
背景情况:
- 半晶体聚合物通过形状变化,晶体滑动或化再结晶来表现出固体到固体相位过渡.
- 结晶学滑动在这些过渡过程中的具体作用,特别是与化再结晶相结合时,仍然不太清楚.
研究的目的:
- 研究在拉伸过程中转-1,4-多聚乙烯 (tPBD) 的晶相过渡和叶片结构演变.
- 阐明固体到固体相变的机制,重点关注结晶学滑动的贡献.
主要方法:
- 作为一个模型的多态聚合物,利用了trans-1,4-polybutadiene (tPBD).
- 在各种温度下 (低,中,高) 进行拉伸实验.
- 分析了晶相过渡和状结构变化,使用未明确说明但结果暗示的技术.
主要成果:
- 在相应的低 (≤20°C) 和高 (70°C) 拉伸温度下,tPBD保留单临床和六角相.
- 在中间温度 (25-50°C) 发生由晶体学滑动主导的固体到固体,单临床到六边形相位过渡.
- 拉伸诱导的六角相位形成是由更高的应变和温度促进的.
结论:
- 晶体学滑动在半晶体聚合物从固态过渡到固态过渡中起着至关重要的作用.
- 该研究提供了关于tPBD中相变的温度和应变依赖性的见解.
- 了解这些转变对于控制聚合物形态和特性至关重要.
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