Influence of gamma rays on the optical characteristics of CPVC/Ag nanocomposite film

In the current study carboxylated polyvinyl chloride/silver (CPVC/Ag) nanocomposite film was prepared. Samples from the CPVC/Ag nanocomposite film (1.5cm x 1.5 cm) were treated with 25-200 kGy gamma dosages. The optical characterization of the treated films has been investigated considering dosage by applying UV spectroscopy and colour difference studies. The optical bandgap, refractive index, Urbach energy, optical dielectric parameters, chromaticity coordinates, tristimulus values, colour intensity and colour intercepts have been calculated and interpreted based on gamma dosages. The bandgap decreased from 4.14 to 3.87 eV with augmenting the gamma dosage upto 200 kGy, together with a rise in the Urbach energy. This is attributed to the domination of crosslinks which damage the crystalline phase. Moreover, the non-treated CPVC/Ag is practically transparent. It demonstrated kindliness to change in colour by gamma treatment, as the colour intensity reached a value greater than 5, meaning permanent colour changes.