New semiconducting copolymers containing alkyl quarterthiophene and alkoxy naphthalene moieties for organic thin film transistors

Abstract

A pi-conjugated alkyl quarterthiophene-based copolymer was synthesized by a Suzuki coupling reaction, and its optical, thermal, and electrochemical and organic thin film transistor properties were characterized. The copolymers showed good solubility in common solvents such as chloroform and toluene, etc. The weight average molecular weight (M (w) ) of PQTHN and PQTON were found to be 9,200 with polydispersity of 1.2 and 30,600 with polydispersity of 2.39, respectively. The structure of PQTHN and PQTON was confirmed using H-1 NMR and FTIR spectroscopy. Solution-processed organic thin film transistors (OTFTs) using PQTON exhibited 6.96x10(-4) cm(2)V(-1)s(-1) as mobility with an on/off ratio of 2.46x10(4).