坚固,可拉伸和热敏的智能水凝
Yi Luo1, Werner Pauer1, Gerrit A Luinstra1
1Institut für Technische und Makromolekulare Chemie, Universität Hamburg, 20146 Hamburg, Germany.
Gels (Basel, Switzerland)
|September 27, 2023
概括
这项研究引入了新的自我愈合,热响应的三重网络水凝. 这些先进材料具有出色的机械性能,自我修复能力和维度稳定性,为新的应用铺平了道路.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
背景情况:
- 水凝在各种应用中至关重要,但往往缺乏自我愈合和强大的机械性能.
- 热敏材料为温度变化提供动态反应.
- 三重网络 (TN) 水凝增强机械强度和弹性.
研究的目的:
- 为了开发自我愈合,热响应的三重网络 (TN) 水凝.
- 为了研究酸 (TA) 度对水凝特性的影响.
- 评估开发的TN水凝的机械性能,自我愈合效率和热响应能力.
主要方法:
- N-异烯酸胺 (NiPAAm) 与功能化聚乙醇 (PVA) 和N,N'-甲基二 (N,N'-甲基二胺) 交叉连接剂的联合聚合.
- 加入低度的酸 (TA) (<1重量%).
- PVA的冷解结晶,X射线衍射 (XRD),差分扫描热度计 (DSC),扫描电子显微镜 (SEM),拉力测试,阶段扫描应变测试和膨胀-解循环测试.
主要成果:
- 成功合成了具有不同TA度的TN水凝.
- 较高的TA度降低了PVA结晶性和晶体大小.
- 一种含有0.5%重量%TA的凝在断裂时表现出高延伸度 (880%),优异的自我愈合效率 (81%),厚度转移性行为,良好的热响应 (膨胀率为13.3) 和增强的尺寸强度.
结论:
- 酸有效地增强了TN水凝的自我愈合,机械和厚性otropic性质.
- 开发的TN水凝表现出机械强度,自我愈合能力和热响应的有希望的平衡.
- 这些材料显示出需要动态和弹性软材料的应用的潜力.
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