Influence of Ion-Beam Bombardment on Physicochemical Properties of PVC Medical Device

Mahmmoud S. Abd-Elmonem*
Analytical Chemistry, National Organization for Drug Control and Research (NODCAR), P.O. Box. 29, Giza, Egypt.

A B S T R A C T
Beams have been found to be widely applicable in improving the structure and physical properties of polymers. In this paper, the effect of ion bombardment on physicochemical properties of low-density polyvinylchloride (PVC) was studied. Polymer samples were bombarded with 3 keV Ar ions to fluencies ranging from 3 × 10¹⁷ to 6 × 10¹⁷ ions cm⁻². The pristine and ion beam bombarded samples were investigated using ultraviolet–visible (UV–Vis) spectrophotometer. The physical and chemical structures of PVC were evidently changed after irradiation. These structural changes are reflected in the mechanical properties of the polymer. Ionizing radiations always have a large effect on the mechanical properties of polymers. This effect differs widely depending on whether the polymer cross links or degrades. The tensile strength of PVC at various ion fluencies was illustrated increase from 10.34 to 15.80 MPa. The optical band gap (Eg) was decreased from ∼4.13 to ∼3.85 eV for the pristine sample and those samples bombarded with Ar ion at the highest influence. The change in the optical gap indicates the presence of a gradual phase transition for the polymer. With increasing ion influence, a decrease in both the energy gap and the activation energy was observed. The number of carbon atoms (N) in a formed cluster is found to be directly proportional to ion influence and is determined according to the modified Tauc equation.
Keywords: ion-beam beam irradiation; optical properties; PVC; medical device