多尺度共轭微孔聚合物的可控合成

Controllable Synthesis of Multi-Scale Conjugated Microporous Polymer

自2007年首次报道以来,作为一种由共轭单元构建的三维聚合物网络骨架,共轭微孔聚合物(Conjugated Microporous Polymer,CMP)通常都是以不溶不熔的固体粉末形式存在;尽管这种材料结合了优异的多孔性、稳定的骨架结构以及多样化的功能,显示了在众多领域的应用价值和广阔前景,但又始终面临着自身性质带来的难以解决的加工性问题.为了让这种材料充分发挥自身优点,应用于除吸附分离等以外的光电、传感、催化等能源环境相关的领域,需要在多尺度范围内调控CMP生长和形成,获得微纳尺度的CMP微球以及宏观尺度的CMP薄膜、涂层或是凝胶,从而提高其溶液性质以便于进一步加工处理,或是直接获得可用于构筑器件的薄膜.从目前的研究进展来看,一共有四种研究策略来解决这一问题,分别是设计合成:(1)可溶性CMP聚合物,(2)溶液可分散CMP纳米微球,(3)CMP(复合)薄膜,(4)有机相CMP化学凝胶.这些工作采用了新的聚合方法、催化剂或功能单体,使CMP材料初步实现了溶液中的加工、组装、复合以及器件的构筑,展示了在光学传感、光电转换、能量存储、非均相催化等优异的性质.尽管目前已报道的工作仍旧面临较多的局限性,然而基于创新的思路和大量的探索,这类新型的功能高分子材料将会逐步成为一个重要的多孔材料分支,具有光明的发展前景.

As it was firstly reported in 2007, conjugated microporous polymer(CMP) has been constructed by a diversity of conjugation building blocks towards a three-dimensional rigid organic framework with the form of insoluble and infusible solid powders. Although CMP has showed the collective characteristics such as exceptional porosity, stable network structure and versatile functionality for potential applications and broad prospects in many fields, the problem of processability concerning this kind of material has not been overcome yet. To take full advantage of their features and break through the application scopes from adsorption and separation to energy and environment such as photoelectric transformation, sensing and catalysis, modulation of growth and formation of CMP in multiple scales is highly anticipated, giving rise to the micro/nanometer-size CMP microspheres and macroscopic CMP films, coatings or gels. Unambiguously, such well-organized forms either have the improved solution properties for further processing, or appear membranes directly assembled into devices. Looking back at the progress of CMP studies in recent years, there are four strategies reported to explore multi-scale CMPs, including(1) soluble CMP-like polymer,(2) solution-dispersible CMP microspheres,(3) CMP-based(composite) film, and(4) CMP-supporting organogel. In these studies, the novel polymerization methods, new catalysts or functional monomers were adopted; the resulting CMPs could be processed, assembled or combined with other materials in solution, and have greatly promoted the performances of optical sensing, photoelectric conversion, energy storage and heterogeneous catalysis on intended devices. It is noted that the reported methodologies have some limitation, but upon the creative ideas and vast explorations, CMP is going to be one important branch of porous materials with promising perspectives.