光致质量迁移效应构筑聚集诱导发光聚合物表面起伏图案

Fluorescent patterns have attracted much attention for their potential applications in photonics, optoelectronics, display technique and other related areas. Much effort has been made to prepare these kinds of patterns by different methods. Among these methods, photoinduced SRGs approach has attracted great attention for its simple fabrication of surface relief patterns. Anyway, as we know that azobenzenes are generally non-fluorescent, the emission of the fluorophores will be prone to quenching by the azobenzene components. In addition, the aggregation of the fluorophores in the solid state will generally debase or quench the emission (ACQ). To resolve these issues, series of photoresponsive aggregation-induced emission (AIE) active polymers containing imidazole-type azo chromophores will be prepared in this project. Surface relief patterns on such prepared polymers can be easily fabricated by irradiation of interference laser beams. Then the imidazole-type azo chromophores will be totally photo-bleached at final stage. In this way, the advantages of the surface patterning technique are used and the quenching effect of azobenzene on the fluorophores will be avoided. This work will provide a fascinating and viable strategy to design and fabricate complex fluorescent patterns.

荧光材料纳/微米图案在光电子学等领域有着重要的应用前景。与纳米压印光刻技术、微接触印刷、掩模光刻技术等方法相比，表面起伏光栅法过程简单只需通过激光光照即可。但表面起伏光栅法需要在材料中引入偶氮基团，而偶氮基团的荧光淬灭效应使得光致表面起伏光栅法的应用受到了非常大的限制。另外，荧光材料的聚集诱导荧光淬灭现象也是荧光材料图案化需要注意的问题。针对上述问题，我们提出了利用含可光降解的咪唑类偶氮苯基团的新型光响应性聚集诱导发光聚合物材料来高效制备荧光表面图案的新方案。在本项目中我们可通过分子设计成功制备上述聚合物，在此基础上，先利用偶氮基团的光致质量迁移特性，再利用其光降解特性来避免偶氮基团对荧光的淬灭效应，同时聚集诱导发光材料的使用又进一步解决了荧光基团自身的聚集诱导荧光淬灭。有关研究结果将在制备系列具有可光加工特性的聚集诱导发光聚合物的基础上，开辟荧光材料表面图案化的高效新途径。

具有刺激响应性荧光材料在光子学、光电子学等领域有着很重要的应用前景，近年来受到了越来越多的关注。设计新颖的刺激响应性荧光材料以及在此基础上发展行之有效的荧光材料图案化方法也是当前研究热点。而上述应用更多的时候荧光分子是处于聚集态，因此本项目以此设计并合成了多种刺激效应性聚集诱导发光聚合物，将不同的刺激响应性功能单元如偶氮苯或donor-acceptor Stenhouse Adduct（DASA）等引入到具有AIE特性的四苯基乙烯（TPE）基体系中，为TPE基材料带来了诸如可见光和化学氧化还原等刺激响应的荧光点亮型聚集诱导发光性能。对相关刺激响应性AIE材料的结构与性能之间的构效关系进行了系统研究。在上述工作基础上进一步实现了聚集诱导发光聚合物材料的表面图案化以及在肿瘤组织内的乏氧荧光成像。上述材料在光信息存储、防伪以及生物成像等领域有着潜在的应用价值。