从香到封闭聚合物:自然和人工泡核化
Carlos Arauz-Moreno1, Keyvan Piroird2, Elise Lorenceau3
1Saint-Gobain Research Paris, Université Grenoble Alpes, CNRS, LIPhy, 38000 Grenoble, France and , 39 Quai Lucien Lefranc, Aubervilliers 93360, France.
Physical review. E
|August 19, 2025
概括
粘弹性材料中的泡生长受温度和气体平衡的影响. 核化机制,无论是自然的还是人工的,都会影响泡的形状和生长速度,类似于香泡.
科学领域:
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
- 物理 物理学 物理
背景情况:
- 气泡核和增长是各种科学和工业应用中的关键现象.
- 了解像粘弹性聚合物这样复杂流体中的这些过程对于预测材料行为至关重要.
研究的目的:
- 在特定条件下实验研究粘弹性聚合物中的气泡核和生长.
- 探索温度,气体平衡和气泡形态之间的关系.
- 分析不同核化机制对泡增长动态的影响.
主要方法:
- 使用Hele-Shaw细胞将粘性弹性聚乙烯丁结合起来.
- 在高温下应用受控解压,以诱导气泡形成.
- 使用显微镜观察和分析泡核,形状和生长.
- 改变了初始核的形态,并引入了人工核化场所.
主要成果:
- 气泡的出现和增长与气体平衡 (水蒸气过和空气过) 的温度变化有关.
- 泡的形状和大小因最初的核形态和接近其他泡而有所不同.
- 由于接触线钉定,观察到大型核的异型增长.
- 核形成的可能性与溶解水含量和温度相关,温度与生长核的数量之间有反向关系.
- 不同的核化机制 (自然与人工) 影响了泡增长率.
结论:
- 这项研究阐明了粘性弹性,气体平衡和气泡动力学之间的复杂相互作用.
- 核化机制显著影响泡增长率,为控制这些系统中的泡形成提供了洞察力.
- 这些发现为了解相位过渡和材料在受限粘弹性流体中的行为提供了基础.
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