Tensity capacitance-resistance effect in the organic semiconductor poly-o-phthalanthracenate under uniaxial compression

In this work an investigation was made of elastic capacitance resistance effects in poly-o-phthalanthracenate (POPhA) pressed samples. Synthesized polymer was in the form of dark brown amorphous powder possessing high thermal stability in air up to 600 K. Electrical resistance and capacitance of the samples were measure under uniaxial pressure. Elastic capacitance resistance effects were found: under uniaxial compression the capacitance of the POPhA increases and its longitudinal resistance decreases. Capacitance and resistance uniaxial pressure dependences were practically the same and quasi linear. piezo capacitive and piezo resistive coefficients were equal to 0.3 10m/Newton. for explanation of the results the POPhA samples were considered as aggregates of semiconducting spherical granules coming into contact with each other. It was shown that the elastic capacitance resistance effect in POPhA is caused both the change in geometrical dimensions of the same and the increase of electrical conductivity and dielectric permeability under uniaxial compression. (author)