A comparison of modifications induced by Li3+ and Ag8+ ion beams irradiation in poly(lactide-co-glycolide) films

Abstract

Poly(lactide-co-glycolide) (PLGA) films were irradiated by 180 MeV/amu Ag8+ ions and 50 MeV/amu Li3+ ions at different fluences of 5 × 1010, 5 × 1011 and 1 × 1012 ions/cm2. Modifications of polymer films induced by the swift heavy ions (SHI) irradiation were studied by X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR) and UV–Vis spectroscopy. The dominant effect of the SHI beam irradiation is proposed to be chain scission which leads to breakage of polymer chains, followed by hydrogen abstraction. The results from FTIR spectroscopy showed that the intensity of all peaks of the irradiated samples decreased at high fluence of SHI, suggesting PLGA samples significantly degraded at high SHI fluence. The variation in optical band gap energy and Urbach energy with increasing fluence was calculated from UV–Vis spectroscopy and explained in terms of changes occurring in the polymer matrix. X-ray diffraction patterns also show appreciable changes in PLGA at high fluence. FESEM results revealed that the hydrophilicity of the PLGA surface increased with an increase in ion fluence. In this paper the optical, chemical and structural changes with different fluence rates are discussed.