在快速正面固化聚合物中,残留菌株的发展
Zhuoting Chen1, Behrad Koohbor2, Xiang Zhang1
1Mechanical Engineering Department, University of Wyoming, Laramie, Wyoming 82071, United States.
ACS applied engineering materials
|November 28, 2024
概括
前端聚合 (FP) 使用外热反应快速固化热. 这项研究模拟了材料演变和残留变形,建议预热以减轻FP制造中的应变.
科学领域:
- 聚合物科学 聚合物科学
- 材料工程 材料工程 材料工程
- 化学工程是化学工程的重要组成部分.
背景情况:
- 前端聚合 (FP) 可快速,节能地制造热和复合材料.
- 商业应用需要更好地预测FP期间的材料演变和残余变形.
- 了解依赖治疗的特性对于设计FP过程至关重要.
研究的目的:
- 在前端聚合过程中实验性地描述和数值模型材料进化.
- 为了捕获和预测FP过程中产生的残留菌株.
- 确定用于减轻FP制造中的残余变形的策略.
主要方法:
- 实验测量二cyclopentadiene的温度和治疗依赖性质 (弹性模块,Poisson的比率,CTE,化学收缩).
- 基于实验数据的结合热化学机械模型的开发.
- 数字模拟以捕捉菌株演变和残留菌株.
主要成果:
- 材料的性能 (弹性模块,波桑比率,CTE,化学收缩) 非常依赖于固化的程度.
- 一个合模型准确地捕获实验测量的残留菌株.
- 与固化速率相关的化学收缩导致应变局部化,特别是在反应前线合并的地方.
- 在合并的前面区域预热单体/凝有效减少剩余变形.
结论:
- 开发的热化学机械模型准确地预测了前部聚合过程中的残余应变.
- 化学收缩是局部残留菌株的主要驱动因素.
- 合并前面区域的预热是一种可行的策略,以最大限度地减少FP应用中的残留变形.
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