Titanium Dioxide and Gamma Irradiation Induced Changes in the Structural, Morphology, and Mechanical Behavior of Ethylene Vinyl Acetate Copolymer

Abstract

Some composites were prepared depending on ethylene vinyl acetate (EVA) copolymer with 18% VA content and titanium dioxide (TiO2). These composites were prepared in the ratios of 100/0, 90/10, 80/20, 70/30, and 60/40 by melt mixing method. Gamma radiation at differing doses was applied on pure EVA and composites to investigate the impact on modification of composites. Gel percentage and the Charlesby‐Pinner equation were used to confirm crosslinking increases. X‐Ray diffraction measurement (XRD), scanning electron microscope (SEM), and mechanical testing were all used to investigate the varying effects of the different processes on the structure, morphology, and mechanical behavior of EVA. It was observed that the addition of TiO2 and gamma irradiation both have a significant effect on the structure and, therefore, the composites' surface morphology. Notable changes of the lattice structure were revealed by the XRD results for both unirradiated and irradiated composites, which were also confirmed by examination of the samples' surface morphology. It was found that the presence and amount of TiO2 along with the irradiation process has a significant influence upon the EVA's mechanical behavior. When compared with the pure EVA, the results demonstrated a significant enhancement in the mechanical parameters of both unirradiated and irradiated composites, except elongation at break. The mechanical results were in line with gel content analysis. The reliability of gamma radiation as an applied method for controlling long‐term properties is clearly demonstrated. J. VINYL ADDIT. TECHNOL., 26:224–235, 2020. © 2019 Society of Plastics Engineers