Study of physical and chemical modifications induced by 50 MeV Li3+ ion beam in polymers

• We irradiated the industrial polymers with Swift Heavy Ions at different fluences.
• Structural effects, optical and chemical changes after irradiation were examined by XRD, UV–Visible and FTIR spectroscopy respectively.
• Increase in crystalline nature and decrease in band gap is observed with increase in fluence.
• Increase in particle size and variation in the Urback′s energy is observed with increase of fluence.
• The modifications caused by SHI in various chemical bonds are also discussed.

Polyether-sulphone and polyamide-nylone-6 polymers were irradiated by 50 MeV Li3+ ions for modifications in structural, optical and chemical properties. The decrease in peak width and increase in peak intensity of XRD spectra indicated alignment of polymeric chains in a regular pattern and hence there was decrease in the amorphous character of the irradiated polymers. The gradual increase in the optical absorption and shift towards visible region was observed in optical absorption spectra of irradiated polymers. The increase in absorption was attributed to the generation of a conjugated system of bonds which lowered the band gap of irradiated polymers to significant values. The thermal fluctuations in the band gap energy due to temperature dependent self energies of the electrons were observed from the calculated values of the Urbach′s energy. The FTIR spectra obtained after irradiation exhibited decrease in absorbance for various bands in case of PN-6 whereas opposite behavior was observed in case of PES polymer.