文摘
The effect of gamma irradiation on the electrical, molecular and structural properties of copolymers of methacrylic esters and olefins, PM-555 solid-state nuclear track detector was investigated. DC conductivity measurements were studied in the temperature range 293–417K using solid-state samples of the PM-555 polymer. These samples were irradiated with gamma doses in the range 5–63kGy. Furthermore, the activation energy was measured, at various temperatures, as a function of the gamma dose. It was found that many changes in electrical resistance of PM-555 polymer could be produced by gamma irradiation via the degradation mechanism. Also, the gamma dose gives an advantage for the increasing correlation between the DC conductivity and the number and mobility of the charge carriers created by the ionizing effect of gamma radiation. Moreover, solutions of different loadings (0.2 % , 0.4 % , 0.6 % and 0.8 % ) were prepared from the irradiated and non irradiated sheets using pure chloroform as a solvent. The effect of both temperature and gamma dose on the intrinsic viscosity of the liquid samples, as a measure of the mean molecular mass of the PM-555 polymer, were studied. In addition, structural and optical property studies using X-ray diffraction and refractive index measurements were performed on all irradiated and non irradiated PM-555 samples. The results indicate that both the degree of ordering or disordering and the anisotropic character of the PM-555 polymer are dependent on the gamma dose.