Recyclable Polycarbosilane from a Biomass-Derived Bifuran-Based Monomer
Recyclable Polycarbosilane from a Biomass-Derived Bifuran-Based Monomer
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DOI：
10.1021/acsmacrolett.3c00095
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发表时间：
2023-04-09
影响因子：
7.015
通讯作者：
Kasuya, Ken-ichi
中科院分区：
文献类型：
--
作者：
Beppu, Shunsuke;Tachibana, Yuya;Kasuya, Ken-ichi
开发下一代聚合物的两个最基本的原则是从可再生生物质生产和精心设计的可回收性。由于其高刚性、强链间相互作用和扩展的π-共轭，联呋喃衍生物代表了用于功能聚合物的有前途的构建块。本研究通过硅氢基联呋喃与1，5-己二烯的硅氢加成反应制备了含二氢呋喃重复单元的聚碳硅烷。由于聚（二叉碳硅烷）单元的刚性和链间相互作用，含二叉碳硅烷的结晶度和热性能上级优于相应的含单呋喃基重复单元的聚碳硅烷，并与苯基类似物的结晶度和热性能相当。与含有基于单呋喃和基于苯的重复单元的聚碳硅烷相比，重复单元中的联呋喃部分引起聚碳硅烷的红移和强UV吸收。联呋喃部分还使得所得聚碳硅烷具有强荧光，而含有基于苯和基于单呋喃环的重复单元的聚碳硅烷不发射荧光。这些理想的光性能的结果从重复单元中的o-pi共轭的扩展。此外，化学可再循环性是基于双呋喃的聚碳硅烷的独特且有吸引力的性质;在用三氟乙酸处理后，双呋喃可以作为单体再生，而三氟乙酸酯硅烷可以向上循环为相应的聚硅氧烷。因此，双呋喃基序赋予聚碳硅烷以改进的热、光学和再循环性能。
Two of the most fundamental principles for the development of next-generation polymers are production from renewable biomass and well-designed recyclability. Bifuran derivatives represent promising building blocks for functional polymers on account of their high rigidity, strong interchain interactions, and extended pi-conjugation. In this study, a polycarbosilane containing a bifuran-based repeat unit was prepared via the hydrosilylation of dihydrosilylbifuran and 1,5-hexadiene. The crystallinity and thermal properties of the bifuran-containing polycarbosilane were superior to those of a correspond-ing polycarbosilane containing a single-furan-based repeat unit and comparable to those of the benzene-based analogue due to the rigidity and interchain interactions of the poly(bifurancarbosilane) unit. The bifuran moiety in the repeat unit causes a red-shift and strong UV absorption of the polycarbosilane compared to that containing the single-furan-based and benzene-based repeat units. The bifuran moiety also renders the resulting polycarbosilane strongly fluorescent, while the polycarbosilanes containing the benzene-based and single-furan-ring-based repeat units did not emit fluorescence. These desirable photoproperties result from the extension of the o--pi conjugation in the repeat unit. Furthermore, the chemical recyclability is a unique and attractive property of the bifuran-based polycarbosilane; upon treatment with trifluoroacetic acid, bifuran can be regenerated as the monomer, while trifluoroacetate silane can be up-cycled to the corresponding polysiloxane. Thus, the bifuran motif endows polycarbosilane with improved thermal, optical, and recycling properties.