Electrical conduction and ultrasound wave propagation in particulate and short fiber composites of PVC. I: PVC‐cu/al particulate composites

Poly(vinylchloride) compositions containing 0–24 v% of copper and 0–48 v% of aluminium powders were prepared and their d.c. electrical conduction and ultrasound wave propagation at 2, 3, 6, 9 MHz were studied. Segregated network formation by the filler as evident by photomicrograph. DTA and X‐ray diffraction, drastically reduces the electrical resistivity in these composites. The limiting resistivity of PVC/Cu composite is 31.62 ohm‐cm and that of PVC/Al composites is 1258 ohm‐cm. Ultrasound wave propagation through these composites having segregated network of fillers shows that absorption at 9 MHz is more in copper filled PVC than in aluminium filled PVC. Dispersion at 9 MHz is more in aluminium filled composites than in copper filled composites. Other parameters, such as excess absorption, relative velocity, relative modulus were evaluated. No definite correlation exists between electrical conduction due to segregated network formation and ultrasound wave propagation.