含聚合物的多阶段可逆光调和硬化
Sirun Yang1, Jared D Harris1, Aloshious Lambai2
1Department of Chemistry, Dartmouth College, Hanover, New Hampshire 03755, United States.
Journal of the American Chemical Society
|September 30, 2021
概括
用水光开关的聚合物的光异构化增加了它们的玻璃过渡温度 (Tg). 这允许在单一材料中获得多个稳定的Tg值,证明光硬化能力.
科学领域:
- 聚合物化学
- 材料科学
- 摄影化学
背景情况:
- 具有可光切换组的聚合物具有可调节的特性.
- 控制玻璃过渡温度 (Tg) 对材料应用至关重要.
- 水光开关表现出双稳定性,允许有不同的Z和E异构体.
研究的目的:
- 研究光异构对聚烯酸和聚甲烯酸聚合物玻璃化温度 (Tg) 的影响.
- 探索具有多个稳定的Tg值的材料的潜力.
- 在含有双稳定光开关的聚合物网络中展示光硬化.
主要方法:
- 聚烯酸和聚甲烯酸聚合物的合成,使用悬挂式双光开关.
- 使用紫外线/Vis光对水单元进行光异构.
- 纳米印记测量以评估机械性能和光硬化.
- 差分扫描热量计 (DSC) 用于确定玻璃过渡温度 (Tg).
主要成果:
- 水悬挂的光异构化导致聚合物的玻璃过渡温度 (Tg) 增加.
- 纳米印记证实了聚合物网络在光异构化后的光硬化.
- 水开关的双稳定性使同一材料内多个Tg值的锁定和维持成为可能.
- 这些多重Tg状态即使在高温下也保持,取决于Z/E同位素比率.
结论:
- 包含双稳定光开关的聚合物具有可光调节的玻璃过渡温度.
- 光硬化效应与水单元的光异构化直接相关.
- 这项研究为开发具有可切换热和机械性能的先进聚合物材料提供了途径.
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