ELECTRICAL STUDIES ON PVA-PE COPOLYMER

The electrical transport properties including electrical conductivity (sigma), dielectrical constant (epsilon'), thermally stimulated depola rization current (TSDC), and pyroelectric coefficient (P) of a poly(vi nyl alcohol)-polyethylene (PVA-PE) copolymer were studied in the tempe rature range 296-433K. Two stages of behavior have been observed with activation energies 1.49 and 0.05 eV. Discussion of conduction mechani sm was carried out in terms of relevant theories. The existence of a r elaxation peak in epsilon' versus T relation has been analyzed taking into consideration space charge effects and dipole orientation phenome na. The TSDC spectra showed two peaks with differing intensity and pos ition independent of field intensity. Pyroelectric current data provid e further support to space charge effects. (C) 1997 John Wiley & Sons, Inc.