在高应变率测试中解开弹性体的相关长度和时间尺度
Katherine M Evans1, Dustin A Baird1, Polette J Centellas1
1Materials Science and Engineering Division, National Institute of Standards and Technology, 100 Bureau Dr, Gaithersburg, Maryland 20899, United States.
Macromolecules
|March 2, 2026
概括
激光诱导膜扩张 (LIME) 显示了三种弹性体的类似高拉伸率模块,尽管它们的准静态特性不同. 该方法量化了快速变形下的能量消耗和聚合物动态.
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
- 机械工程 机械工程
背景情况:
- 对于涉及快速变形的应用,了解高拉伸率弹性体的机械性能至关重要.
- 测量高延展率属性的传统方法可能是复杂和有限的.
- 激光诱导膜膨胀 (LIME) 提供了一种新的方法来探测这些特性.
研究的目的:
- 使用LIME研究三种不同的弹性体的高拉伸率机械性能.
- 模拟空洞事件作为和振器,以确定剪切模量和散射.
- 分析弹性活性聚合物长度及其在能量消耗中的作用.
主要方法:
- 利用激光诱导的膜扩张 (LIME) 来诱导弹性体样本中的腔化.
- 模拟了使用和振器框架的化事件.
- 定量化的剪切模量和能量消耗是聚乙烯-异乙烯-乙烯 (SIS),线性聚二甲基 (lPDMS) 和瓶刷PDMS (bPDMS) 的变压率的函数.
主要成果:
- 通过LIME测量的高延展率切割模块在三个弹性体中是相似的.
- 在近静态条件下观察到剪切模块的显著差异.
- 计算了弹性活性的聚合物长度,提供了对能量消散机制的洞察力.
结论:
- 在高应变率下,弹性体的行为可以惊人地均,尽管网络结构各异.
- LIME是一种有效的技术,用于表征高应变率的机械性能和能量消耗.
- 这些发现对设计聚合物有影响,这些聚合物具有针对动态应用的量身定制的能量存储,释放和消散能力.
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