We report the "green" synthesis and characterization of a series of fused benzo[1,2-b:4,5-b′]bis[b]benzothiophene (BBBT) polymers containing a phenyl ring and naphthalene as comonomers, as well as BBBT homopolymers. These novel fused polymers have been obtained from simple acid and hexaethyltriaminophosphine catalyzed polymerization without involving any metal catalyst. The effect of the different aromatic units on the optical and electronic properties of the resulting polymers has been studied. It was found that these polymers possess high electron affinities due to the presence of electron-deficient lactams on each repeat unit. BBBT-P and BBBT-N exhibit NIR absorption spectra with the tail extending to 1000 nm, while the BBBT homopolymer exhibits a large blue-shifted absorption.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-30
Acknowledgements: The authors thank the NSF of China (Grant No. 21875291 and 21702240) for the financial support. L. Yao thanks Guangxi University for Nationalities Graduate Education Innovation Project (gxun-chxps201819) and the specific research project of Guangxi for research bases and talents (AD18126005) for the financial support. MKR thanks the SRM Supercomputer Centre, SRM Institute of Science and Technology for providing the computational facility.