聚合物的结晶和晶体形态:一个多相场研究
Navid Afrasiabian1, Ahmed Elmoghazy2, Juliane Blarr3
1Department of Physics and Astronomy, Univeristy of Western Ontario, London, ON, Canada.
概括
这项研究提出了聚合物结晶的新粗粒度模型,模拟了微观结构的演变. 该模型准确地预测了碳纤维如何影响晶体形态和生长,为复合材料的行为提供了洞察力.
科学领域:
- 材料科学 材料科学 材料科学
- 计算建模 计算建模
- 聚合物科学 聚合物科学
背景情况:
- 了解聚合物结晶对于材料性能至关重要.
- 现有的模型可能对混合物和复合材料等复杂系统缺乏灵活性.
- 微观结构的进化显著影响最终的材料性能.
研究的目的:
- 介绍一种用于聚合物结晶的新型粗粒度模型.
- 研究碳纤维对结晶形态和运动学的影响.
- 分析冷却速度和初始谷物分布的影响.
主要方法:
- 一个多相场的方法与纳卡穆拉的运动方程和热传导相结合.
- 在异热和非异热条件下的微结构演变的模拟.
- 适用于整洁的PA6和PA6/碳纤维复合材料系统.
主要成果:
- 该模型在质量上与实验相对晶度数据一致.
- 碳纤维促进更均的晶体形态和垂直的谷物生长.
- 较高的初始晶体分数和纤维热导率有助于观察到的效应.
结论:
- 开发的模型有效地模拟了整洁和复合系统中的聚合物结晶.
- 碳纤维作为核化场所,由于几何和热效应,影响晶体形态.
- 观察到的垂直增长归因于表面限制,而不是内在的增长方向.
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