偶氮聚合物Janus粒子及其光致形变功能研究

Azo polymers are well-known for their interesting properties as photoresponsive materials. Janus particles (JPs), named after the roman god Janus, are generally referred to noncentrosymmetric nano/micrometer particles. On the basis of the concepts of JPs, different kinds of materials with various interesting properties can be incorporated into one single particle to realize novel functionalities. As a new research frontier, azo polymer JPs can integrate photoresponisve functions of azo polymers with the unique symmetry-breaking architecture of JPs. This proposed project plans to carry out the systematic study on azo polymer JPs from the preparation of polymers to fabrication of JPs, structure control, photoinduced deformation, multi-functionalities, and possible applications. The study will be dedicated to understand the phase separation of azo polymers and the other polymers in confined volumes in order to establish practical methods. Through self-assembly of azo polymers and other types of polymers in confined volumes, i.e., via phase separation in dispersion (emulsion) and phase inversion approaches, the project will fabricate various JPs with controllable structures and properties. The proposed project plan to fully elucidate the effects of the mutual interactions, restricted nucleation and growth in the systems on the structure formation, condition adjustments and optimization. Different light irradiation conditions (uniform, non-uniform and varied polarization states) will be explored to achieve unique types of symmetry-breaking deformations. Based on the results, new types of JPs with multi-functionalities are proposed to be developed for future applications. This study on the novel types of JPs is valuable for both fundamental understanding and smart photofabrication in micrometer scale.

偶氮聚合物是一类光响应性新材料，Janus粒子（JPs）为非中心对称结构新型胶体粒子。具有光致形变功能的偶氮聚合物JPs是结合上述领域的全新研究方向。本项目以具有光致形变功能的偶氮聚合物JPs为研究对象，拟深入研究聚合物和JPs结构的制备、调控、光致形变机理、结构性能关系和应用。重点研究利用悬浮液（乳液）法和相反转法制备偶氮聚合物JPs的优化条件。致力阐明偶氮聚合物和非偶氮聚合物两种组分在受限空间发生相分离的微观机理，通过偶氮聚合物和其它聚合物在受限空间的自组装，得到各种结构和性能可调的JPs。阐明各种的相互作用对相分离过程和JPs结构形成的影响规律。掌握各种光辐照方式（非均匀光场、均匀光场、不同偏振态等）对偶氮聚合物JPs形变的影响规律。建立各种新型偶氮聚合物JPs的制备方法，拓展功能性，并探索其应用。研究此类新型的Janus粒子具有重要的科学研究价值和应用前景。

偶氮聚合物是一类光响应性新材料。Janus粒子具有非中心对称的结构，是目前国内外研究的热点。具有光致形变功能的偶氮聚合物Janus粒子（JPs）是结合这两个领域的全新研究方向。本项目以具有光致形变功能的JPs为研究对象，合成了JPs制备所需的偶氮聚合物、偶氮分子玻璃和其它功能材料，深入研究了各种JPs的制备、结构调控、光致形变机理、结构性能关系和应用等。重点研究了利用悬浮液分散法制备偶氮聚合物JPs的优化条件，并建立相应的制备方法。阐明了偶氮聚合物和非偶氮聚合物两种组分在受限空间发生相分离的微观机理。利用荧光聚合物作为一相，通过荧光分子探针功能，系统表征了JPs形成过程中的相分离、聚并和固化对应的时间系列。通过建立的显微镜原位观察的方法，揭示了组分的相分离和聚并的动力学过程。通过偶氮聚合物和其它聚合物在受限空间的自组装，得到各种结构和性能可调的JPs。包括偶氮聚合物和荧光聚合物的JPs，具有定性黏附和协同光致形变功能的JPs等等。在此基础，建立了利用悬浮液分散法制备偶氮聚合物三相粒子的新方法，将功能性粒子的制备从Janus粒子拓展到三相粒子能显著拓展材料的功能性。阐明了各种相互作用对相分离过程、JPs结构和三相粒子形成的影响规律。上述研究建立了制备各种新型偶氮聚合物JPs和三相粒子的方法，阐明了不同偏振态等光辐照对偶氮聚合物JPs和三相粒子形变的影响规律，拓展了偶氮聚合物和偶氮分子玻璃的功能性和应用领域。研究工作已发表SCI收录的文章18篇，核心刊物收录的文章一篇。这些文章发表在Adv. Funct. Mater., Adv. Optical Mater., Soft Matter, Langmuir等刊物上。另有6篇文章在写作和修改中。上述研究成果具有重要的科学价值和潜在的应用前景。