直接测量和建模自由立体薄聚烯薄膜的粘弹性-粘可塑性质
Yuhan Xiao1, Pei Bai1, Zhengyang Zhang1
1University of Michigan-Shanghai Jiao Tong University Joint Institute, Shanghai Jiao Tong University, Shanghai 200240, China.
The Journal of chemical physics
|December 6, 2023
概括
这项研究揭示了纳米限制如何影响薄聚合物薄膜. 粘度和屈服应力随着薄膜厚度的降低而增加,影响其非线性粘弹性-粘可塑性质.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物物理 聚合物物理
背景情况:
- 薄聚合物薄膜对于涂料和电子包装等应用至关重要.
- 聚合物薄膜的纳米级机械性能与散装材料有很大的不同.
- 理解在纳米限制下非线性粘弹性-粘可塑性行为是必不可少的.
研究的目的:
- 为了研究独立的薄聚烯薄膜的非线性粘弹性-粘可塑性质.
- 探索纳米限制对这些机械行为的影响.
主要方法:
- 气泡膨胀方法用于机械测量.
- 用于建模的Shapery和Perzyna方程.
- 对薄型聚钢 (PS) 薄膜的分析.
主要成果:
- 玻璃的合规性保持不变,而的硬化被观察到.
- 下部状高原可能是由于塑性变形引起的分子取向造成的.
- 粘度和屈服应力分别以指数和线性增加,随着薄膜厚度的下降.
结论:
- 纳米封闭显著改变了薄聚合物薄膜的粘性塑料特性.
- 需要进一步的研究,以充分理解从线性粘性弹性到在纳米限制下非线性粘性弹性-粘性弹性的过渡.
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