全息光聚合诱导的纳米晶原位生成与有序复合

Holographic polymer nanocomposites represent one type of important recording media for holography. As well recognized, it remains a critical challenge to simultaneously enhance the processing efficiency and the holographic performance. Toward this end, this project intends to develop a novel approach for reconstructing holographic polymer nanocomposites in a single step via the in-situ formation of nanocrystals upon holographic photopolymerization. In details, homogenous solutions will be prepared by dissolving the perovskite nanocrystal precursors, organic ligands and the photoinitibitor into the mixed monomers. The in-situ formation and ordered arrangement of perovskite nanocrystals are expected when irradiating the solution by the laser interference patterns, giving rise to the in-situ formation of ordered polymer nanocomposites. The influence factors on the in-situ formation of perovskite nanocrystals will be deeply investigated and precisely regulated. Subsequently, by carefully changing the material compositions and holographic recording parameters, the in-situ formation kinetics of perovskite nanocrystals, system gelation behaviors and the formation process of ordered structures will be finely tuned, which eventually leads to the generation of high-performance holographic polymer/perovskite nanocrystal composites. Both holographic and photoluminescent functions will be integrated into a single holographic polymer/perovskite nanocrystal composite thanks to the 3D image recording capability of holography and the photoluminescent nature of perovskite nanocrystals. The outcomes of this project are envisioned not only to offer new ideas to the design and fabrication of ordered polymer nanocomposites, but also to enrich the theory system of functional polymer materials.

全息聚合物纳米复合材料是全息信息存储的重要媒介，如何同步提升其加工效率与全息性能是关键难题。针对该难题，本项目拟基于全息光聚合诱导纳米晶原位生成的原理一步法制备全息聚合物纳米复合材料。具体地，将钙钛矿纳米晶前驱体、有机配体、光引发阻聚剂和单体混合均匀，然后在相干激光照射下通过光聚合反应诱导钙钛矿纳米晶原位生成及规整排列，实现钙钛矿纳米晶与聚合物的原位有序复合。探究光聚合诱导纳米晶原位生成规律及其调控方法，优化体系组成和全息加工条件以调控复合体系的全息光聚合行为，进而有效调控纳米晶原位生成行为、体系凝胶化行为和有序结构形成过程，最终制得高性能全息聚合物/钙钛矿纳米晶复合材料。在全息聚合物/钙钛矿纳米晶复合材料中存储三维全息图像，结合钙钛矿纳米晶的光致发光性能，实现全息图像存储与光致发光功能集成。项目的顺利实施，将为结构有序聚合物纳米复合材料的设计与制备提供新思路，丰富功能高分子材料理论体系。

全息聚合物/钙钛矿纳米晶复合材料具备全息图像和荧光图像存储能力，在高端防伪、显示等领域具有广阔的应用前景。然而，由于存在制备过程繁琐、效率低、需要使用大量挥发性有机溶剂等问题，限制了实际应用。针对上述问题，项目首先建立了一种制备全息聚合物/钙钛矿纳米晶复合材料的新方法。该方法通过全息光聚合诱导相分离形成有序结构，同时诱导钙钛矿纳米晶原位生成，一步制备全息聚合物/钙钛矿纳米晶复合材料。经优化，全息聚合物/钙钛矿纳米晶复合材料的衍射效率达93.1% ± 3.7%、感光灵敏度达2.34 cm/mJ。在复合材料中存储了裸眼可见的三维全息图像，实现了全息和荧光功能的集成。此外，项目在光聚合单体中原位合成了钙钛矿纳米晶，通过光聚合反应原位制备了聚合物/钙钛矿纳米晶复合材料，制备过程完全无需使用有机溶剂。这种复合材料可以通过光聚合3D打印成型，并且由于钙钛矿纳米晶降低了光穿透深度，从而提升了3D打印成型精度。最后，在聚合物/钙钛矿纳米晶复合材料中引入卤代烷，通过光致卤素交换反应精确调控了复合材料的荧光性质，在复合材料中存储了荧光颜色分别为蓝-绿、红-绿的荧光图像。项目为结构有序聚合物纳米复合材料的绿色、高效制备提供了新思路，丰富了功能高分子材料理论体系。