Dielectric properties on the radiation and thermal aged PEEK

The dielectric properties of gamma-ray irradiated and thermally aged polyetheretherketone (PEEK) have been investigated. Results of the temperature dependency of the dielectric properties indicated that the glass transition temperature of the aged PEEK increased with radiation and thermal ageing. The frequency dependency of dielectric properties implied that the magnitude of radiation and thermal induced dipoles and ions increased as radiation and thermal ageing. The values of the relaxation intensity calculated using Cole-Cole's circular arc can be useful for the evaluation of the degradation level of PEEK.