Synthesis and characterization of copolymers composed of 3-hexylthiophene and fluorene via chemical oxidation with FeCl3

Abstract

A series of conducting copolymers including fluorene (F) and 3-hexylthiophene (3HT) were synthesized in chloroform via chemical oxidative polymerization with FeCl3. The incorporation of 3HT and fluorene units into the resultant polymer main chain was verified via proton nuclear magnetic resonance (1H NMR) and matrix-assisted laser desorption/ionization mass spectrometry. During copolymerization, the molar ratios of fluorene and thiophene changed (0 to 100%). Thus, the fluorene content in the copolymers was proportional to that of the fluorene fed into the polymerization reaction mixture. Ultraviolet–visible (UV–Vis) and fluorescence spectra indicated that the absorption and emission peak wavelengths of the resulting copolymer were significantly affected by the fluorene content. The quantum yield determined using the relative method increased from 0.26 to 0.73 with an increase in the fluorene content. The thermal stability of the copolymers also improved with the presence of fluorene. A series of conducting copolymers including fluorene (F) and 3-hexylthiophene (3HT) were synthesized in chloroform by chemical oxidative polymerization with FeCl3, and the incorporation of fluorene and 3HT units into the resultant copolymer main chain was clarified. The quantum yield value of obtained copolymers determined by relative method increased by the amount of incorporated fluorene molecules in the resulting copolymer backbone. In addition, fluorene was demonstrated to play an important role in enhancing the thermal stability of the copolymers.