Title:
Reversible Functionalization of Conjugated Aromatic Polymers via Imine Linkage for Electronic Applications
Authors: T. Eppler [1,2], G. Liu [3], M. Wang [3], X. Feng [3], B. Voit [1,2]
Affiliations: [1] Leibniz-Institut für Polymerforschung Dresden e.V., Germany; [2] Technische Universität Dresden, Professur für Organische Chemie der Polymere, Germany;
[3] Technische Universität Dresden, Professur für Molekulare Funktionsmaterialien, Germany
Abstract:
A variety of materials, based on reversible imine formation, have been reported in the literature, including well studied examples such as covalent organic frameworks (COFs), linear aromatic and non-aromatic polymers and their corresponding post functionalized derivatives. [1-3] Various applications have been discussed for such materials, including catalysis, gas storage, sensing, drug delivery, usage in batteries and (opto)electronic devices. [4] Furthermore, linear aromatic imine polymers are a promising candidate in green chemistry, due to the possible recycling under highly acidic aqueous conditions. [5]
In this work, strategies towards reversible imine functionalization of linear, aldehyde moiety containing polymers are reported under solvothermal conditions. As precursor, covalently linked benzodithiophene-bithiophene (BDT-BT) polymers are used. Functionalization with aniline and pyrazine derivatives is carried out to test and tune the (opto-)electronic properties of the obtained material. To establish suitability for application in electronic devices, typical characterization methods such as cyclovoltammetry and UV/Vis measurements are applied in both solution and on thin film. Following the complete characterization of the obtained imine polymers, highly acidic, aqueous conditions allow defunctionalization, therefore testing the reusability of the polymer backbone with various substitution patterns. Naturally occuring additives are used to allow recycling at milder conditions
The combination of a highly conducting BDT-BT linear polymer and aniline/pyrazine derivative functionalization via imine linkage in this work is expected to yield remarkable (photo-)electronic properties to allow later usage in devices, while still allowing effective (re-)functionalization, tuning the properties and recycling the used materials.
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