用合成弹性体模拟生物应力-应变行为
Mohammad Vatankhah-Varnosfaderani1, William F M Daniel1, Matthew H Everhart1
1Department of Chemistry, University of North Carolina at Chapel Hill, North Carolina 27599, USA.
Nature
|September 5, 2017
概括
研究人员开发了一种新方法来制造具有可调节的机械性质的聚合物弹性体,模仿生物组织. 这种方法精确地控制材料的行为,
科学领域:
- 聚合物化学
- 材料科学
- 生物材料工程
背景情况:
- 在合成材料中实现机械柔软性,强度和性的特定组合是具有挑战性的.
- 生物组织表现出这些特性,使其成为医疗植入物,组织工程,软机器人和可穿戴电子产品的理想模型.
- 目前的材料合成方法往往是经验性的,限制了对机械性能的精确控制.
研究的目的:
- 为合成精确模仿生物组织机械行为的聚合物网络提出总体策略.
- 展示如何使用特定的架构参数来对材料编码所需的应力-应变曲线.
- 能够开发出适合各种应用的先进材料.
主要方法:
- 开发了一种无溶剂合成策略,用于制造类似刷子和的聚合物网络 (弹性体).
- 使用三个独立的架构参数:网络链长度,侧链长度和接种密度,作为"代码"来决定材料属性.
- 用于实验验证的原型聚甲烯弹性体.
主要成果:
- 成功证明所选择的参数三重组精确地控制合成弹性体的机械行为.
- 复制生物组织,包括水母,肺和动脉组织中观察到的应变强化的特征.
- 展示了在聚合物网络中编码特定应力-张力曲线的能力.
结论:
- 提出的策略为设计具有仿生机械性质的聚合物弹性体提供了通用和精确的方法.
- 这种方法克服了传统的爱迪生合成的局限性,允许可预测和可控的材料设计.
- 这些发现为制造先进的软材料在医学和工程领域的应用铺平了道路.
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