Poly[2-methoxy-5-(2';-ethylhexyloxy)-(p-phenylenevinylene)] (MEH-PPV) synthesized via a modified Gilch method and the electrical conductivities of MEH-PPV/MCMB films

Abstract

Poly[2-methoxy-5-(2'-ethylhexyloxy)-(p-phenylenevinylene)] (MEH-PPV) was obtained via the modified Gilch route. The expected polymer was obtained in an overall yield of 19.5%. The structures of all synthesized intermediates and MEH-PPV fully complied with their respective spectroscopic data using 1H and 13C nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectroscopies. Thermal properties of the polymer was studied using simultaneous thermogravimetry and differential scanning calorimetry (TGA/DSC) and morphologies by transmission electron microscopy (TEM). The glass transition temperature, Tg, of MEH-PPV was obtained at 85 °C. TEM results showed that the material was amorphous. Results showed that pure MEH-PPV exhibited high impedance at room temperature but the impedance increases in the MEH-PPV/MCMB composite. The MEH-PPV/MCMB composite film shows an increase in conductivity of the order of 2. The enhancement of conductivity of MEH-PPV by the addition of MCMB was attributed to the change in morphology of the film and contribution of electrons by carbon in the polymer matrix.