Synthesis and characterization of copolymer Poly [(Thiophene-2, 5-diyl)-co-para methoxy benzylidene] doped with Cobalt acetate using Oxidative polymerization

Abstract

A one pot oxidative polymerization technique is used to synthesize copolymer Poly [(thiophene-2, 5-diyl)-copara methoxy benzylidene]. In this technique we used catalyst POCl3 and 1, 4 dioxane solvent for copolymerization of para methoxy benzaldehyde with thiophene. One pot method takes around 24 hours. Doped copolymer was synthesized in presence of 0.2gm cobalt acetate. Catalyst is removed using ammonia. Products are obtained using menthol. UV–Vis, FTIR, 1HNMR, 13CNMR, XRD, FE-SEM, EDX, BET and TGA are used to analyze physical properties of undoped and doped copolymers. The polycrystalline phase is confirmed using structural analysis. Interconnected nonoporous structure is indicated by surface morphology. The nano crystalline sizes of undoped and doped forms are 44 nm and 55 nm respectively. The surface area changed due to cobalt doping of copolymer from 3000 to 47900cm2/g. Both copolymers are thermally stable up to 280oC confirmed by thermogravimetric analysis. Optical absorption studies proved that band gap changed from 2.93 to 2.83 eV after doping and two-probe method was used to calculate conductivity values as 1.34 x 10-9to 7.54 x 10-8 S/cm for undoped and doped copolymers. Both undoped and doped copolymers have several uses like semiconducting material and energy storage in the field of conducting polymers.