Conductivity of polyaniline/1,2,4-trichlorobenzene composites during freezing and melting transitions

Polyaniline suspensions in 1,2,4-trichlorobenzene produced solid composites after freezing. Changes in electric conductivity after the solidification and during the melting transition have been investigated in dependence on c onducting polymer concentration. Below the percolation threshold, the condu ctivity of frozen composites was lower than that of original suspensions. I f conducting particle concentration was above this critical value, then the conductivity increased after the suspension froze. Conductivity both in th e liquid and in the solid state was higher when polyaniline particles in th e suspensions were polarized in electric field. In this case, conductive pa thways connecting the electrodes were produced by organized particle chains . (C) 2001 Elsevier Science BN. All rights reserved.