使用多模管模型预测高密度聚乙烯融解病变,该模型是使用非平衡热力学推导的
Pavlina C Konstantinou1, Pavlos S Stephanou1
1Department of Chemical Engineering, Cyprus University of Technology, P.O. Box 50329, 3603 Limassol, Cyprus.
Polymers
|August 12, 2023
概括
聚合物的新型风学模型准确地预测了材料的行为,包括应力下拉,并且与高密度聚乙烯树脂的实验数据有很好的一致性.
科学领域:
- 非平衡的热力学.
- 聚合物转化学 聚合物转化学
- 构成模型的建构模型.
背景情况:
- 现有的模型在热力学定律方面存在局限性,并且无法预测诸如压力下射等复杂的风质现象.
- 一般化支架 (或贝里斯-爱德华兹) 形式主义为先进的学模型提供了基础.
研究的目的:
- 扩展和验证最近提出的聚合物和溶液的差异构成模型.
- 评估模型对工业聚合物系统,特别是高密度聚乙烯 (HDPE) 的预测能力.
主要方法:
- 开发差异构成模型的多模式版本.
- 模型预测与HDPE树脂的实验性风学数据的比较.
- 在不同的流量条件中验证:小振幅振荡剪切,启动剪切和启动单轴延伸.
主要成果:
- 多模式模型成功地预测了风湿反应,包括短暂的压力下拉.
- 该模型在各种剪切和延伸测试中与HDPE的实验数据有很好的一致性.
- 改进的模型克服了先前版本关于对流约束释放参数和热力学一致性的局限性.
结论:
- 经过验证的多模式构成模型是研究纠聚合物系统的质学的一个有前途的工具.
- 该模型能够准确预测工业聚合物行为的能力提高了其在材料科学和工程中的实际适用性.
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