Modification of polythiophene by the incorporation of processable polymeric chains: Recent progress in synthesis and applications

Intrinsically conductive polymers (ICPs) have attracted significant attention in recent decades because of their wide range of potential applications in various fields such as chemistry, physics, electronics, optics, materials, and biomedical sciences. In particular, conjugated polythiophene (PTh) and its derivatives stand out as the most promising members of the conjugated polymer family because of their unique electrical behavior, excellent environmental and thermal stability, low-cost synthesis, and mechanical strength. However, similar to other π-conjugated polymers the main drawback of unsubstituted PTh is the lack of solubility due to its strong interchain interactions, resulting in limited processability. Various procedures have been invoked to overcome these restrictions, such as side chain functionalization, the synthesis of PTh copolymers with processable polymers, and combination of both of these strategies. Because of large number of publications on the chemical modification of polythiophene, this review is focused on progress in the synthesis of polythiophene copolymers with processable polymers. The properties of the polythiophene copolymers and their applications are also highlighted.