为什么切割比撕裂弹性体更容易?
Donghao Zhao1, Alex Cartier1, Tetsuharu Narita1
1Laboratoire de Sciences et Ingénierie de la Matière Molle, ESPCI Paris, CNRS, PSL University, Paris, France.
Nature communications
|April 3, 2025
概括
撕裂像这样的软固体需要比切割更多的能量,因为拉伸会导致分子损伤. 这项研究量化了弹性体中的键裂变,解释了为什么撕裂比切割更难.
科学领域:
- 材料科学 材料科学 材料科学
- 材料机械学 材料机械学
- 聚合物科学 聚合物科学
背景情况:
- 撕裂软固体 (,皮革,肉类) 比切割要耗费更多的能量.
- 了解软材料中断裂和切割的机制对于各种应用至关重要.
研究的目的:
- 为了研究软固体中切割和撕裂力学之间的差异.
- 量化与每个过程相关的分子损伤和能源需求.
- 阐明弹性体中预拉伸,化和断裂能量之间的关系.
主要方法:
- 使用机械敏感的光剂来标记聚甲基氧 (PDMS) 弹性体样本.
- 在预拉伸的PDMS样本中研究了切割和骨折行为.
- 使用光技术量化了裂纹尖端附近的键裂和变形.
- 测量了断裂能量,并将其与断裂的聚合物链的密度相关联.
主要成果:
- 预拉伸弹性体中的拉伸诱导的裂会导致显著的变形,键裂裂变,裂尖端变,增加传播能量.
- 使用刀片切割可以最大限度地减少拉伸和形,导致与撕裂相比,骨折能量更低.
- 在断裂能量和破碎的聚合物链的面积密度之间观察到线性相关性.
- 多尺度的洞察力揭示了软材料中断裂和切割力学之间的明显差异.
结论:
- 由于减少了分子损伤和变形,切割比撕裂软固体更节能.
- 该研究阐明了骨折和切割能量的差异背后的分子机制.
- 这些发现可以优化加工,食品工业,回收和生物医学设备的工程应用.
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