上转换粒子辅助的NIR聚合使微域梯度光聚化在粒子间长度尺度上成为可能
1International Research Center for Photoresponsive Molecules and Materials, Jiangnan University, Wuxi, 214122, Jiangsu, PR China.
Nature communications
|June 20, 2023
概括
上转化颗粒辅助NIR聚合 (UCAP) 能够使光聚合物材料具有高交叉连接和低收缩应力. 这种新的方法通过在凝前释放应力来增强机械性能.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 光聚合的光聚合方式.
背景情况:
- 在光聚合物中同时实现高交叉连接和低收缩应力是具有挑战性的.
- 传统的紫外线聚合技术往往会导致严重的内部压力.
- 提高性能的光聚合物材料需要仔细控制固化过程.
研究的目的:
- 引入和研究一种新的光聚合方法,使用上转换粒子辅助的NIR聚合 (UCAP).
- 证明UCAP能够降低收缩应力,同时提高固化材料的机械性能.
- 阐明UCAP实现这些改进的独特机制.
主要方法:
- 利用在NIR激发后发射UV-VIS光的上转化粒子.
- 实施一个以上转换粒子为中心的域限梯度光聚合过程.
- 监测固化系统的状态 (液体,凝) 和功能组转换.
- 将机械性能和收缩应力与传统紫外线聚合物的比较.
主要成果:
- 在粒子中心域内,UCAP会诱导梯度光聚合.
- 固化系统保持流动性,直到高功能组转换,在凝之前释放压力.
- 经UCAP固化材料表现出高凝点转换率和显著较低的收缩应力.
- 通过UCAP固的材料与传统的UV固对应物相比,具有优越的机械性能.
结论:
- 向上转换粒子辅助的NIR聚合 (UCAP) 提供了一种独特的机制,以克服交叉连接和收缩应力之间的权衡.
- UCAP 便于制备具有增强机械强度和降低内部应力的高性能光聚合物材料.
- 这种方法为开发先进的光聚合物应用提供了有希望的进步.
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