Polyfluorene–poly(ethylene oxide) diblock copolymers: synthesis and electron transport behavior

Under mild reaction conditions, we synthesized diblock copolymers of poly(9,9-dioctylfluorene)-block-poly(ethylene oxide) (PFO-b-PEO) via end-capping poly(9,9-dioctylfluorene) (PFO) with poly(ethylene oxide) (PEO) on one end. We investigated the thermal, optical, electrochemical and crystalline properties as well as electron transport performance of these polymers. Our results demonstrate that PFO-b-PEO diblock copolymers with short PEO chains (Mn = 1000 and 2000 g mol−1) exhibit higher electron mobilities compared to the PFO homopolymer and longer PEO chain (Mn = 4000 g mol−1) attached copolymers. This enhanced electron mobility is attributed to the higher crystallinity induced by the shorter PEO chain end-capping.