Iminoboronate Polymers as Dynamically Adaptable, Photoactive Materials

含有动态共价键的聚合物形成了一类“智能”材料，能够适应--或可以改变--施加的化学或环境刺激。我们提出了一类新的动态，共轭聚合物的基础上可逆亚胺硼酸酯键合基序。含有醛、胺和硼酸官能团的简单AB型单体将与二醇聚合，生成亚胺硼酸酯聚合物。正交动态亚胺和硼酸酯键的存在将使我们能够开发出易于官能化、从而可调的多组分聚合物材料，这些材料具有对各种外部刺激进行重组或适应的能力。通过引入电子上不同的二元醇，共轭聚亚胺聚合物主链的光物理性质可以被调节，为获得所需的材料性质提供了一条可预测的途径。这种材料体系的一组独特特性--高度可调的电子性能、通过N-B键合成稳定的结构刚性以及由于非共轭硼官能化而产生的电化学稳定性--有望使这些聚合物成为发光器件的有力候选者。(此外，对亚胺硼酸盐与电子不同的二元醇的亲和力有了基本的了解，将使我们能够通过连续的二元醇交换促进聚合物性质的连续变化。)这些材料将作为特定二元醇的荧光多受体，以及作为添加或取代四氢呋喃的可控交联性或解交联性材料进行研究。这些高价值智能材料的开发将为下一代多功能器件奠定基础，例如具有比最先进的聚(荧烯)OLED更高的效率和电化学稳定性的蓝色发光聚合物。

Polymers incorporating dynamic covalent bonds form a class of "smart" materials that are able to adapt to-or can be altered in response to-applied chemical or environmental stimuli. We propose a new class of dynamic, conjugated polymers based on the reversible iminoboronate ester bonding motif. Simple AB-type monomers incorporating aldehyde, amine, and boronic acid functionalities will polymerize together with diols to produce iminoboronate ester polymers. The presence of orthogonal dynamic imine and boronate ester bonds will allow us to develop easily functionalizable, and thus tuneable, multicomponent polymer materials that possess the ability to reorganise or adapt in response to various external stimuli. By incorporating electronically distinct diols, the photophysical properties of the conjugated polyimine polymer backbone may be tuned, providing a predictable pathway for attaining desired material properties. The unique set of characteristics of this materials system - highly tuneable electronic properties, structural rigidity through dative N-B stabilisation and electrochemical stability due to non-conjugated boron functionalization - promise to make these polymers strong candidates for light-emitting devices. (Additionally, obtaining a fundamental understanding of the affinity of the iminoboronate for electronically different diols will allow us to promote consecutive changes in polymer properties through successive diol exchanges.) These materials will be investigated as fluorescent polyreceptors for specific diols and as controllably crosslinkable or decrosslinkable materials with the addition or displacement of tetrols. Development of these high-value smart materials will lay the groundwork for the next generation of multifunctional devices, such as blue-light-emitting polymers with superior efficiency and electrochemical stability to the state-of-the-art poly(fluorene) OLEDs.