聚合物对聚合物表面的粘附和摩擦机制
Nobuo Maeda1, Nianhuan Chen, Matthew Tirrell
1Department of Chemical Engineering, College of Engineering, University of California, Santa Barbara, CA 93106, USA.
概括
聚合物表面的摩擦和粘附取决于链条动力学. 交叉连接的聚合物比不交叉连接的聚合物具有较低的摩擦力,在表面链修改后观察到的摩擦力和粘附力增加.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物科学 聚合物科学
- 部落学 (tribology) 是一个学科.
背景情况:
- 了解聚合物表面特性对于应用至关重要.
- 粘附和摩擦是聚合物表面相互作用的关键参数.
研究的目的:
- 研究聚合物链动态对粘附和摩擦的影响.
- 探索表面链结构如何影响部落学行为.
主要方法:
- 利用表面力装置研究低于其玻璃过渡温度的聚合物表面.
- 检查了交联和未交联的聚合物样本.
- 在诱导链裂后,研究了粘附和摩擦的变化.
主要成果:
- 交叉连接的聚合物相比,与未交叉连接的聚合物相比,摩擦力显著较低.
- 在表面层的链裂后,粘附歇斯底里和摩擦大幅增加.
- 从交叉连接到长链到准自由的末端表面的过渡与增加的粘附和摩擦有关.
结论:
- 聚合物聚合物粘附歇斯底里和摩擦是由表面聚合物段的动态重新排列所支配的.
- 表面链状况极大地影响了部落学属性.
- 结果表明,通过控制表面链动态来调整聚合物表面粘附和摩擦的方法.
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