在超软的凝上移动湿
Hansol Jeon1, Youchuang Chao1, Stefan Karpitschka1
1Max Planck Insitute for Dynamics and Self-Orgnization, 37077 Göttingen, Germany.
Physical review. E
|September 19, 2023
概括
软聚合物凝的动态湿是复杂的. 毛细管油的提取似乎是最有希望的,而常见的弹性毛细管缩放无法预测山脊形状,但提供了可行的动态角度预测.
科学领域:
- 软物质物理学 软物质物理学
- 表面科学是一门科学.
- 聚合物科学 聚合物科学
背景情况:
- 软固体上的湿现象对于自然和技术应用至关重要.
- 软聚合物凝作为研究静态和动态湿的模型系统.
- 对于凝上湿的现有理论模型缺乏共识,需要实验验证.
研究的目的:
- 实验性地研究超软聚合物凝上的移动湿的形状,具有高时空分辨率.
- 将实验结果与从线性粘性状毛细体理论的预测进行比较.
- 评估不同理论模型的有效性,包括弹性毛细体缩放和毛细体提取.
主要方法:
- 在不同硬度的聚甲基 (PDMS) 凝上测量了湿形状的高分辨率测量 (约. 100 Pa) 的时间.
- 实验采用不同的湿阶段进行:水,FC-70和空气.
- 实验数据与线性粘性状毛囊理论的非对称行为进行比较.
主要成果:
- 通常使用的弹性毛囊缩放不准确地崩湿形状.
- 弹性毛囊缩放在小的正常力下提供了可行的预测,用于在小的正常力下动态角.
- 既没有辩论的理论模型完全解释了观察到的现象量化.
- 油的毛细血管提取是最有可能的机制.
结论:
- 这项研究强调了目前关于软凝动态湿化的理论描述的局限性.
- 实验证据表明,毛细血管提取是湿脊形成的主要因素.
- 需要进一步的理论发展,以充分捕捉软固体在湿过程中的复杂表面力学.
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