Ultraviolet Spectral Analysis of Polyvinyl (Butyral) Film Incorporating 10, 12-Pentacosadiynoic Acid Monomer for Application in Radiation Processing Dosimetry

A detailed study was performed to investigate the dosimetric characteristics of polyvinyl butyral (PVB) containing 10,12-pentacosadiynoic acid (PCDA) monomer. PCDA monomer undergoes radiation polymerization when subjected to gamma rays inducing change in the absorption spectra in the UV region of the spectrum. Unirradiated film is colourless and has four absorption peaks at 216 nm, 227 nm, 241 nm and 256 nm. Upon irradiation two new peaks at 271 nm and 286 nm are developed and their amplitudes with the original peaks increase with the increase of absorbed dose. The useful dose range of this film is 3 - 100 kGy depending on PCDA monomer concentration. The effects of temperature and relative humidity during irradiation on the dosimeter performance as well as pre- and post-irradiation stability at different storage conditions are discussed. The overall combined uncertainties (at 2 σ) associated with dose measurement are estimated