ZnS Nanocrystals as an Additive for Gamma-Irradiated Poly (Vinyl Chloride)

Zinc sulfide (ZnS) was synthesized by sonochemical method and nanoparticles with crystallite size around 2 nm were obtained. PVC containing ZnS nanoparticles at concentrations of 0.10; 0.30; 0.50; 0.7 and 1.00 wt% were gamma irradiated (60Co) at room temperature in air. No appreciable decrease in PVC Viscosity-Average Molar Mass (Mv) was observed for samples containing 0.7 wt% of ZnS nanocrystals. It was demonstrated that the addition of ZnS nanocrystals imparted molecular protection to the polymer matrix while improving flexibility, by decreasing the Young Modulus of PVC films. These results suggest the use of sonochemically synthesized ZnS nanocrystals as a new additive for radiation-grade PVC materials.