Characterization of Optical Modification in Polyethersulfone due to Irradiation with Si and Ne ions

Abstract

Irradiation of the polymeric materials with radiation results into the modification of their physico-chemical properties due to the transfer of high value of energy by the heavy ions causing unusual density of electron hole pairs close to the ion path. Films of 250 μm thickness of the polymer, Polyethersulphone (PES) were irradiated to Si⁸⁺ ions of energy 100 MeV to the fluences of 1 x 10¹⁰, 1 x 10¹¹, 1 x 10¹² and 5 x 10¹² ions/cm² and Ne⁶⁺ ions of energy 145 MeV to the fluences of 1 x 10¹² and 1 x 10¹³ ions/cm². Optical modifications were characterized by UV-Vis. Spectroscopy is found to decrease with transferred energy density of the ion beams. The energy band gap (E_g) values were computed from the absorption edge in the 200-800 nm region. E_g varied from 2.68 to 1.63 eV in Si⁸⁺ irradiated PES samples and from 2.68 to 1.61 eV Ne⁶⁺ irradiated PES samples. The cluster size varied in a range of 6 to 11 carbon atoms per cluster.