可持续聚乙烯等材料的多态化和拉伸诱导的变化
Hamed Janani1, Stephanie F Marxsen1, Marcel Eck2
1FAMU-FSU College of Engineering, Department of Chemical and Biomedical Engineering, 2525 Pottsdamer Street, Tallahassee, Florida 32310, United States.
ACS macro letters
|January 23, 2024
概括
生物衍生聚烯在低火温度下形成六角晶体,在更高温度下形成正方形晶体. 六角形的形状在加热或拉伸时转变为正方形,增强了材料的性.
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:
- 生物衍生,可生物降解和可回收的阿里法基聚烯为传统塑料提供了可持续的替代品.
- 了解这些聚合物的晶体结构对于定制它们的机械性能至关重要.
研究的目的:
- 为了研究类似聚乙烯的生物衍生聚合物的晶体结构.
- 探索不同晶体形式之间的热和机械转换.
- 识别结构-属性关系,以提高材料性能.
主要方法:
- 聚乙烯类聚烯 (PE-2,18) 在不同温度下灭.
- 不同扫描热度计 (DSC) 和X射线衍射 (XRD) 用于结构分析.
- 单轴拉伸变形实验,以研究机械反应.
主要成果:
- 六角晶体结构在~50°C以下火时形成,其特点是形状障碍.
- 在更高的火温度或在异热结晶过程中,具有全跨CH2序列的正方体类型的包装形式.
- 六角晶体通过融再结晶在60°C左右转化为正方体晶体.
- 单轴拉伸变形诱导了拉伸诱导的变化,从六边形到正角形的结构.
- 这种转变导致更大的应变和增强的应变硬化,提高材料性.
结论:
- 生物衍生聚烯表现出不同的晶体结构,取决于加工条件.
- 六角形晶体形式通过拉伸诱导的相变提供了通过延伸诱导的相变来增强机械性能的途径.
- 这些发现为设计更坚固,高性能可生物降解聚合物提供了洞察力.
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