Effect of Low Gamma-Irradiation Doses on Cellulose Triacetate Polymer Films: I. Dispersion Properties

In the work, optical behavior of cellulose triacetate films and related parameters are investigated under the effect of low dose gamma irradiation. The irradiation by a 10 kGy got success to reduce the refractive index of the cellulose triacetate polymeric film to reach 10.3% of its original value. At this irradiation dose the material dispersion is decreased by 65% associated with a reduction of 64% in the ratio between carrier density to the effective mass of carrier. The average oscillator strength and the average interband oscillator wavelength are suffered also drop of 36% and 15.3% in their initial values, respectively. An increase of about 18.6% in the band gap energy is achieved also with a dose of 10 kGy. The chemical bond approach and electronic polarizability are used to analysis and explain the results.