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带状球状岩的跨晶机制 在融化结晶半晶聚合物中的发展
1Department of Chemical Engineering, Biotechnology and Materials, Faculty of Engineering, Ariel University, Ariel 40700, Israel.
Polymers
|September 14, 2024
概括
聚合物中的带状形成是由顺序的透晶性解释的,而不是连续的扭曲. 这种对带状球状石形成的新理解为聚合物加工和设计提供了洞察力.
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:
- 带状球体中连续状扭曲的传统模型受到最近不连续性发现的挑战.
- 以前的研究缺乏解释这些在聚合物球体中观察到的不连续性.
研究的目的:
- 调查和证明带状球状岩石形成背后的主要机制.
- 阐明了顺序的透晶性在带状聚合物球体的发展中的作用.
- 为带状球体中观察到的不连续性提供机械解释.
主要方法:
- 对三种半晶体聚合物的实验研究:高密度聚乙烯 (HDPE),聚乙烯糖醇 (PEG10000) 和Pluronic F-127.
- 在各种融流条件下分析带状球状岩的形成,包括散装流,界面接触和流.
- 显微镜检查以识别和描述球状岩及其构成层的形态.
主要成果:
- 连续的透晶性,以自我剪切导向的无形层为核心,被确定为带状球状岩石形成的主要机制.
- 晶体层可以在由融流方向的无形聚合物链上核化,甚至在像气泡或样品边缘这样的接口上.
- 在生长过程中,无形材料的过度排斥会导致脱位,并通过跨晶层核形成启动螺旋带.
结论:
- 这项研究揭示了顺序的透晶性作为带状球体的占主导地位的形态和形成机制.
- 这一发现挑战了长期存在的连续层扭曲的范式.
- 了解这种机制可以为设计聚合物加工技术和应用带来新的见解.
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