Synthesis, Thermal and Electrical Properties of 2, 2’-HBBF Copolymer Resin

Abstract

The copolymer (2, 2'-HBBF) synthesized by the condensation of 2, 2'-dihydroxybiphenyl (2, 2'-HB) and biuret (B) with formaldehyde (F) in the presence of acid catalyst using 1:1:2 molar proportions of the reacting monomers. The thermogravimetric analysis of copolymer resin prepared in the present study has been carried out by non-isothermal thermogravimetric analysis technique in which sample is subjected to condition of continuous increase in temperature at linear rate. The advantage of Freeman-Carroll method is to calculate both the order of reaction (n) and energy of activation in one single stage by keeping heating rate constant. By using data of thermogravimetric analysis, various thermogravimetric parameters like frequency factor (Z), entropy change (ΔS), free energy change (ΔF) and apparent entropy (S*) have been determined using Freeman-Carroll method. The electrical properties of 2, 2'-HBBF copolymers were measured over a wide range of temperature (303-423 K). From the electrical conductivity of these copolymers, activation energies of electrical conduction have been evaluated and values lies in the range 3.01x10 -20 - 6.43x10 20 J/K. On the basis of above studies, these copolymers can be ranked as semiconductors.