Abstract We report the design and synthesis of a series of bisisoindigo‐based donor–acceptor (D–A) copolymers, P4F18, P4F10, P2F18, and P2F10. By reverse evolution of fluorine substitution and side‐chain structure, we effectively tuned the frontier molecular orbital energy levels, intermolecular interactions, molecular self‐assembly, and thus charge transport properties, achieving high electron mobilities of exceeding 7 cm 2 ·V −1 ·s −1 . Our results show that the copolymers bearing the 4‑decyltetradecyl side chain (P4F10 and P2F10) exhibit higher electron mobility than their counterparts with the 4‑octadecyldocosyl one (P4F18 and P2F18). Furthermore, the copolymers based on 2F‑bisisoindigo (P2F18 and P2F10) display significantly enhanced electron transport relative to those derived from 4F‑bisisoindigo (P4F18 and P4F10). The variation in electron mobility correlates well with the thin‑film microstructure of each copolymer. Our results demonstrate that strategic molecular simplification through optimized fluorine substitution and side chain engineering constitutes an effective approach for developing high‐performance polymeric semiconductors.
Shi et al. (Thu,) studied this question.