heal.abstract |
The results of electrical and dielectric studies in semicrystalline nylon II (degree of crystallinity 62%) by means of dielectric relaxation spectroscopy (DRS) in the frequency range 10(-2)-10(6) Hz at temperatures between the glass transition temperature of about 40 degreesC and the melting temperature of about 190 degreesC are reported. Emphasis is put on the investigation of electrical conductivity and conductivity effects. Additional information on de conductivity is obtained from triangular voltage measurements. The results of DRS were analyzed within the formalism of permittivity (ac conductivity), impedance, and electric modulus. At temperatures higher than about 100 degreesC the spectra are dominated by de conductivity and conductivity current relaxation. Despite high values of de conductivity (sigma (dc)=10(-6)-10(-5)S/m at 170 degreesC), electrode effects and space charge polarization, giving rise to high values of epsilon' at low frequencies, are negligible in the whole temperature range of measurements. This feature, as well as the rather small temperature dependence of static dielectric permittivity, su-e important with respect to technological applications of nylon 11 as a high-temperature electroactive material. (C) 2000 American Institute of Physics. [S0021-8979(00)06324-6]. |
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