可切换的全彩反射光子圆粒子
Qilin He1, Kang Hee Ku1, Harikrishnan Vijayamohanan1
1Department of Chemistry, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, United States.
Journal of the American Chemical Society
|May 28, 2020
概括
研究人员开发了可切换的光子圆形聚合物颗粒,使用了树枝化刷块共聚物. 这些粒子表现出动态的颜色变化, 可以用磁场控制, 为智能材料提供新的可能性.
科学领域:
- 聚合物科学
- 材料科学
- 纳米技术
背景情况:
- 开发可调节的光子材料对于先进的光学应用至关重要.
- 块共聚物的自组提供了复杂纳米结构的途径.
- 控制粒子形态和光子特性仍然是一个挑战.
研究的目的:
- 合成全彩反射光子圆形聚合物颗粒.
- 实现动态的颜色变化和磁场辅助的控制.
- 探索树枝化刷块共聚物 (den-BBCPs) 的自组装行为.
主要方法:
- 从乳液中自组装den-BBCP的溶剂蒸发.
- 使用树突性单体表面活性剂来控制界面特性和粒子形状.
- 调整分子重量以控制可见光谱中的光子颜色.
- 使用磁纳米粒子进行功能化,用于开启/关闭颜色.
主要成果:
- 球形的BBCP粒子转变为条纹圆体.
- 快速自组装产生了大域 (153 nm ≤ D ≤ 298 nm).
- 在圆体内形成了高度排列的层 (>100层) 的光子多层.
- 通过改变分子重量 (4771144 kDa),可以在可见光谱中调整颜色.
- 磁性纳米颗粒可以实时切换颜色.
结论:
- 可以自行组装成光子圆体.
- 磁场辅助的激活提供了启/关色控制.
- 这些粒子代表了一类可切换的光子材料.
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