Abstract
Nowadays, ion bombardment became one of the powerful methods usually carried out to modify the surface characteristics of the polymeric materials. In this work, low-density polyethylene (LDPE) polymer samples were bombarded with different fluences by 130 keV He-ion beam. The X-ray diffraction patterns of the untreated sample as well as those exposed to He-ion beam revealed the crystalline nature of the samples. The effects of He-ion beam bombardment on the structural parameters e.g. crystal size, dislocation density, inter-chain separation, micro-strain, and distortion were studied. The optical absorption coefficient and refractive index were calculated as a function of He-ion beam fluences. The optical energy gap and Urbach energy were also evaluated. Wemple-DiDomenico effective single oscillator and Sellmeier models were both used to describe adequately the refractive index dispersion in the low absorption region. Graphical representation of the complex dielectric constant and dissipation factor was also presented. A significant modification in the structural and optical parameters was obtained by ion bombardment technique.
•Influence of He-ion on the surface properties of polyethylene was investigated.•Alterations in the structure of bombarded polymer with increasing ion fluence.•Remarkable variation in optical parameters with He-ion beam fluences.•The refractive index dispersion in the low absorption region is adequately described.•Ion beam bombardment improves the structural and optical properties of polyethylene.