Observation of Dynamic Strain Hardening in Polymer Nanocomposites
Observation of Dynamic Strain Hardening in Polymer Nanocomposites
复制标题
DOI：
10.1021/nn103104g
复制
发表时间：
2011-04-01
期刊：
影响因子：
17.1
通讯作者：
Ajayan, Pulickel M.
中科院分区：
文献类型：
--
作者：
Carey, Brent J.;Patra, Prabir K.;Ajayan, Pulickel M.
大多数材料对施加的应力做出弹性或非弹性的响应，而重复加载会导致机械疲劳。相反，骨骼和其他生物力学组织在承受反复的弹性应力时也有增强的能力。垂直排列的碳纳米管/聚(二甲基硅氧烷)纳米复合材料的循环压缩载荷显示出一种在合成材料中未曾见过的自增强效应。此行为会导致刚度的永久性增加，直到动应力被移除，并在重新应用时恢复。这种效应也是特定于动态载荷的，类似于生物结构中发生的局部的、自我增强的：这些观察有助于阐明基质材料和纳米结构之间的复杂相互作用，而对这一机制的控制可能导致适应性结构材料和活性、承重的人造结缔组织的发展。
Most materials respond either elastically or inelastically to applied stress, while repeated loading can result in mechanical fatigue. Conversely, bones and other biomechanical tissues have the ability to strengthen When subjected to recurring elastic stress. The cyclic compressive loading of vertically aligned carbon nanotube/poly(dimethylsiloxane) nanocomposites has revealed a self-stiffening response previously unseen in synthetic materials. This behavior results In a permanent increase in stiffness that continues until the dynamic stress is removed and resumes when it is reapplied. The effect is also specific to dynamic loads, similar to the localized, self-strengthening that occurs in biological structures: These observations help to elucidate the complex Interactions between matrix materials and nanostructures, and control over this mechanism could lead to the development of adaptable structural materials and active, load-bearing artificial connective tissues.