Modifications induced by O+8 ion beam to Lexan polycarbonate

High-energy ion beam irradiation of polymer is an effective technique to enhance the optical, structural and mechanical properties. Lexan polycarbonate films were irradiated by oxygen ions (energy 100 MeV, charge state O+8) with fluence varying from 3x10(10) to 3x10(12)ions/cm(2). Ion beam-induced optical and structural modifications were studied by ultraviolet-visible (UV-Vis), X-ray diffractometer and Fourier Transform Infrared (FTIR) spectroscopy. It is observed that optical absorption increases with increasing fluencies. The absorption edge was also found to shift from the UV region to the visible region. Value of band gap shows a decreasing trend with increasing ion fluences. The correlation between the optical band gap and number of carbon atoms inside the carbon clusters embedded in the network of Lexan has been discussed. X-ray Diffraction (XRD) analyses show the significant change in crystallinity with fluences. FTIR spectra show that the intensity of the absorption bands of Lexan polymer decreases after ion beam irradiation.