聚烯在结晶和化过程中的粘弹性特性:实验和现象学建模
Noëlle Billon1, Romain Castellani1, Jean-Luc Bouvard1
1Mines Paris, PSL University, Centre for Material Forming (CEMEF), UMR CNRS 7635, 06904 Sophia Antipolis, France.
Polymers
|September 28, 2023
概括
这项研究探讨了聚合物在化和结晶过程中的粘性弹性,发现微观结构,而不仅仅是晶体部分,影响机械性能. 这有助于建模增材制造中的残余应力.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
- 类风病学 类风病学 类风病学
背景情况:
- 在半晶体聚合物中建模残余应力需要了解相位过渡期间的粘弹性行为.
- 目前用于聚合物结晶的初始建模方法是不够的.
- 增材制造涉及准静态结晶条件,需要精确的修态模型.
研究的目的:
- 估计结晶和融对储存和损失模块的影响.
- 开发一个综合微观结构参数的现象学模型.
- 研究结晶动力学与机械效应之间的关系.
主要方法:
- 差分扫描热量计 (DSC) 用于热分析.
- 光学显微镜用于微观结构观测.
- 振荡式剪切体质学用于粘弹性性能测量.
主要成果:
- 一个现象学模型是使用实验推导的宏观参数来开发的.
- 在恒定冷却速率下结晶的模型可行性被评估.
- 风病学建模需要的不仅仅是晶体分数;球状微观结构是关键.
结论:
- 仅仅使用结晶分数是不够的准确的风湿学建模.
- 整合球状层次的微观结构提供了一个更有效的建模方法.
- 实验结果提高了对结晶动力学和机械性质相关性的理解.
相关概念视频
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