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辅助性聚合物网络:交联,密度和混乱的作用
Andrea Ninarello1,2, José Ruiz-Franco1,3, Emanuela Zaccarelli1,2
1CNR Institute of Complex Systems, Uos Sapienza, Piazzale Aldo Moro 2, 00185 Roma, Italy.
The Journal of chemical physics
|December 18, 2023
概括
低交叉连接的聚合物网络表现为负波桑值.
科学领域:
- 聚合物物理 聚合物物理
- 材料科学 材料科学 材料科学
- 软物质物理学 软物质物理学
背景情况:
- 低交叉连接的聚合物网络可以在张力下显示辅助性行为 (负波松比, ν < 0).
- 钻石状网络在机械稳定性极限时表现出超性 (ν = -1),表明了临界性.
- 这种现象对材料科学和基本物理学都有影响.
研究的目的:
- 为了研究聚合物网络中超性现象.
- 探索网络结构 (有序与无序) 和数字密度对弹性性质的作用.
- 用现象学弹性理论验证模拟结果.
主要方法:
- 聚合物网络的平衡和应力-应变模拟.
- 现象弹性理论的应用.
- 对钻石状和无序网络结构的研究.
主要成果:
- 在类似钻石的聚合物网络中证实了超辅性行为 (ν = -1).
- 证明在无序的网络中,超辅助性行为和类似临界现象会持续存在.
- 确定数字密度作为弹性性质的关键控制参数.
结论:
- 这项研究证实并扩大了对高分子网络 (包括无序系统) 中超性 (hyper-auxeticity) 的理解.
- 这些发现表明,数量密度对于调整弹性反应至关重要.
- 在无序网络中这种现象的强度支持了对水凝等材料的潜在实验研究.
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