Effects of swift heavy ion beam irradiation on the structural and morphological properties of poly(methacrylic acid) cross-linked gum ghatti films

Poly(methacrylic acid) (PMAA) chains were cross linked onto the backbone of gum ghatti (Gg) using N,N′-methylene-bis-acrylamide (MBA) and ammonium persulfate (APS) as a cross linker-initiator system in a vacuum oven. The cross linking of the PMAA chains on the polysaccharide backbone was confirmed by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. Later, the cross-linked polysaccharide samples were irradiated at room temperature with 100 MeV O7+ ion beam irradiation at various fluences from 1 × 1011 to 3 × 1012 ions/cm2. We have observed noticeable modifications in the structural and morphological properties after irradiation. The XRD study reveals the gradual decrease in peak intensity with an increase in the ion fluence, which reflected a loss of crystallinity after irradiation. The FTIR spectra show a decrease in intensity of the typical bands at the higher fluence. Different causes of these modifications are discussed.