Dithienobenzimidazole‐containing conjugated donor–acceptor polymers: Synthesis and characterization. Issue 1 (14th December 2018)

• Record Type: Journal Article
• Authors: Harris, Jared D.; Stihl, Markus; Schmidt, Hans‐Werner; Carter, Kenneth R.
• Is Part Of: Journal of polymer science. Volume 57:Issue 1(2019)
• Page Start: 60
• Page End: 69
• Publication Date: 2018-12-14
• Subjects: addition polymerization -- conducting polymers -- conjugated -- dithienobenzimidazole -- donor–acceptor -- semiconducting polymer -- ionomers -- synthesis; 547
• DOI: 10.1002/pola.29284
• Languages: English
• ISSNs: 0887-624X

Abstract

ABSTRACT: The synthesis of two new conjugated polymers based on the relatively under‐exploited monomer, 5, 8‐dibromo‐2‐[5‐(2‐hexyldecyl)‐2‐thienyl]‐1 H ‐dithieno[3, 2‐ e :2′, 3′‐ g ]benzimidazole (dithienobenzimidazole, DTBI ), and either 4, 7‐bis[4‐hexyl‐5‐(trimethylstannyl)‐2‐thienyl]‐2, 1, 3‐benzothiadiazole (BTD ) or 2, 6‐bis(trimethylstannyl)‐4, 8‐bis(5‐(2‐ethylhexyl) thiophen‐2‐yl)benzo[1, 2‐ b :4, 5‐ b ′]dithiophene (BDT ) is described. The polymers were synthesized via Stille polycondensation and characterized by traditional methods ( 1 H NMR, gel‐permeation chromatography, matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry, thermal gravimetric analysis, differential scanning calorimetry, ultraviolet–visible spectroscopy, photoluminescence, and cyclic voltammetry). Prior to their synthesis, trimer structures were modeled by DFT calculations facilitating a further understanding of the systems' electronic and geometric structure. Polymers were titrated with acid and base to take advantage of their amphiprotic imidazole moiety and their optical response monitored with ultraviolet–visible spectroscopy. Finally, pristine polymer thin‐films were treated with acid and base to evaluate (de)protonation's effect on system electronics, but thin‐film degradation was encountered. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem.2019, 57, 60–69 Abstract : This report describes the synthesis and characterization of two new semiconducting conjugated polymers. The polymers' structure is scrutinized using matrix‐assisted laser desorption/ionization‐time of flight spectroscopy and the effect of adding acid and base to the amphiprotic polymers is assessed. These analyses reveal interesting observations regarding these unique systems, which shed light upon areas in need of improvement in conjugated polymer synthesis.