Thickness effect on electric resistivity on polystyrene and carbon black- based composites

摘要: Changes on electrical resistivity were experimentally studied for polystyrene and carbon black-based composites respect to the temperature. 22% w/w black composite films at 30 μm, 2mm y 1cm thick submitted thermal heating-cooling cycles from room temperature 100°C, slightly up Tg of composite. For each cycle changes constituent a hysteresis loop that depends sample thickness. The during heating stage could be explained as consequence expansion mobility polymer chains Tg, producing disconnecting contacts among particles an important increasing (200%) resistivity. cycle, was observed in thicker samples, whereas ? m thickness lost after four cycles.