The influence of gamma irradiation on the intrinsic properties of cellulose acetate polymers

Ionizing radiation of polymers is a promising technique that has found applications in various fields such as food preservation, pharmaceutical production and natural bioactive agent industries. Irradiation technology has several advantages like controlling the degree of degradation, producing uniform molecular weight distribution, saving chemicals and environmentally friendly process. This study was carried out to evaluate the effect of γ-irradiation on the physical and structural properties of cellulose acetate (CA) polymer. Solid disks of CA were exposed to a cobalt-60 source (50 kGy) for different periods of time. Dilute solutions of irradiated and non-irradiated CA were prepared and studied viscometrically and refractometrically. γ-irradiation of CA causes a decrease in the values of relative, specific, reduced and intrinsic viscosities. In addition, there is a reduction in the values of molar mass, hydrodynamic volume, real and ideal chain dimensions and the characteristic ratio of CA. On the contrary, γ-irradiation increased the values of Schulz–Blaschke constant, critical concentration and solute–solvent interaction. However, the values of refractive index, dielectric constant, solubility parameters and cohesive energy density of the polymer in dilute solutions are decreased due to the effect of γ-irradiation.