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Makrofol-N polycarbonate was irradiated with carbon (70 MeV) and copper (120 MeV) ions to analyze the induced effects with respect to optical and structural properties. In the present investigation, the fluence for carbon and copper beams was kept in the range of 1 × 10 11 -1 × 10 13 ions/cm 2 to study the swift heavy ion induced modifications. UV-VIS, FTIR and XRD techniques were utilized to study the induced changes. The analysis of UV-VIS absorption studies revealed that the optical energy gap was reduced by 17% on carbon irradiation, whereas the copper beam leads to a decrease of 52% at the highest fluence of 1 × 10 13 ions/cm 2 . The band gap can be correlated to the number of carbon atoms, N , in a cluster with a modified Robertson's equation. In copper (120 MeV) ions irradiated polycarbonate, the number of carbon atoms in a cluster was increased from 63 to 269 with the increase of ion fluence from 0 to 1 × 10 13 ions/cm 2 , whereas N is raised only up to 91 when the same polymer films were irradiated with carbon (70 MeV) ions under similar conditions. FTIR analysis showed a decrease in almost all characteristic absorption bands under irradiation. The formation of hydroxyl (−OH) and alkene (C=C) groups were observed in Makrofol-N at higher fluence on irradiation with both types of ions, while the formation alkyne end (R−C≡CH) group was observed only after copper ions irradiation. The radii of the alkyne production of about 3.3 nm were deduced for copper (120 MeV) ions. XRD measurements show a decrease in intensity of the main peak and an increase of the average intermolecular spacing with the increase of ion fluence, which may be attributed to the structural degradation of Makrofol-N on swift ion irradiation.

Thin polystyrene films are irradiated with protons (3 MeV) under vacuum at room temperature with the absorbed dose ranging from 2 Â 10 6 to 2 Â 10 7 Gy. The changes in color, increase of cross-linking, and induction of microstrain on the surface of proton-irradiated polystyrene are investigated with UV-VIS, Fourier transform infrared (FTIR) spectroscopy, and X-ray diffraction (XRD) techniques, respectively. There are minimal changes in these properties up to 6 Â 10 6 Gy, which is much more than the 25 kGy radiations needed for sterilization.

The samples of polypropylene (PP) have been irradiated with 120 MeV 64 Cu 9+ and 70 MeV 12 C 5+ ion beams, with the fluence ranging from 1 × 10 13 to 1 × 10 11 ions/-cm -2 . UV-VIS and FTIR techniques have been used to study the chemical and optical properties of these irradiated polymers. UV spectra revealed that the optical-gap energy decreases by 54 % with copper ion irradiation at the fluence of 1 × 10 13 ions/cm 2 , whereas at the same fluence, carbon beam decreases the optical-gap energy by 20%. FTIR analysis of ion irradiated samples revealed the presence of -OH, C = O and C = C bonds. Alkyne formation has been observed only in the case of copper ion irradiation.