Comparative impact of gamma radiation on reinforced nitrile rubber with graphite and agro waste activated carbons

In this article, graphite fine powder and two types of activated carbon (AC) namely based-on waste corn and sugarcane bagasse were implemented as reinforcers for the nitrile rubber (NBR). Both types of AC were prepared through a low-temperature chemical carbonization treatment. Each type of these fillers, at 5, 10, and 15 wt%, was mixed with NBR on a rubber mill and pressed under heat to develop sheets to be gamma irradiated at 100 kGy. Filler characterization using Fourier Transform Infrared spectrophotometer (FTIR) spectroscopy and scanning electron microscopy (SEM) were discussed. X-ray diffraction (XRD) proved that graphite has a crystalline structure but corn and bagasse ACs have amorphous nature. Furthermore, dynamic light scattering (DLS) analysis was used to determine the particle size of the studied fillers. In addition, mechanical properties, XRD, thermal stability, and SEM of the prepared unirradiated or irradiated NBR‒composites were investigated. The physicomechanical features of the NBR matrix could be enhanced by the presence of reinforcing fillers, even at relatively low filler loading. The composites filled with graphite showed superior mechanical parameters and also have the highest thermal stability as indicated by their high-temperature mass loss (Tm). Generally, irradiated samples expressed grander properties than unirradiated ones as a result of the radiation-induced crosslinking structures.