Direct arylation polymerization toward a narrow bandgap donor–acceptor conjugated polymer of alternating 5,6‐difluoro‐2,1,3‐benzothiadiazole and alkyl‐quarternarythiophene: From synthesis, optoelectronic properties to devices

Abstract

Direct arylation polymerization (DAP) enabled facile synthesis of a narrow bandgap donor–acceptor conjugated polymer (PDFBT‐Th4) composed of alternating 5,6‐difluoro‐2,1,3‐benzothiadiazole and alkyl‐quaternarythiophene. The optimized reaction condition of DAP catalyzed with Pd(OAc)2/(o‐MeOPh)3P/PivOH/K2CO3 in o‐xylene led to the target polymer with a number‐average molecular weight (Mn) of 14.6 kDa without noticeable homocoupling or β‐branching defects. UV‐vis absorption spectra of PDFBT‐Th4 indicate strong interchain aggregation in films. While the C‐H selectivity and the alternating polymer structure of PDFBT‐Th4 synthesized via DAP are comparable to those of the same type polymers synthesized via Stille coupling, the batch of PDFBT‐Th4 synthesized via optimal DAP, despite its lower Mn, showed higher hole mobility in field effect transistors and larger power conversion efficiency in organic solar cell devices. These results further demonstrate the promising potential of DAP for efficient synthesis of high‐performance D‐A conjugated polymers for broad optoelectronic applications. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 1869–1879

A Novel Conjugated Polymer Consists of Benzimidazole and Benzothiadiazole: Synthesis, Photophysics Properties, and Sensing Properties for Pd2+

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Synthesis, Self‐assembly, and Fluorescence Application of Bottlebrush Polyfluorene‐g‐Polycaprolactone with Conjugated Backbone and Crystalline Brushes

“…[ 27,28 ] This is because the creation of such novel fluorophores would lead to advances in organic solid‐state light‐emitting devices. [ 29 ] Thus, to suppress the aggregation of conjugated groups and enhance photoluminescence efficiencies are also the important ways for exploring the practical application of luminescent materials. [ 30 ]…”

Recent developments in the synthesis of regioregular thiophene-based conjugated polymers for electronic and optoelectronic applications using nickel and palladium-based catalytic systems

“…In 2017, Amsalu Efrem and co-workers developed a direct arylation polymerization (DArP) protocol for the synthesis of high performance, narrow bandgap donor-acceptor conjugated polymer 263, composed of alternating alkylquaternarythiophene and 5,6-diuoro-2,1,3-benzothiadiazole units. 278 A series of DArP optimization led to the target molecule with a number average molecular weight (M n ) of 14.6 kDa without noticeable b-branching effects and homocoupling.…”