Fabrication and characterization of gamma-irradiated nanomarble/acrylonitrile and styrene butadiene rubber nanocomposites

A comparative study on two nanocomposites based namely on acrylonitrile-butadiene (NBR) and styrene-butadiene (SBR) synthetic rubbers, reinforced by varying ratios of waste nanomarble particles (WM) was carried out. Silane which served as coupling agent was applied in treating waste marble (TWM) and the characters of the prepared nanocomposites before and after treatments were examined. Nanocomposites were fabricated using a laboratory roll mill and pressed under heat, then irradiated with gamma-rays at 100 kGy. Filler characterization, using the techniques transmission electron microscopy (TEM), FTIR spectroscopy, and X-ray diffraction (XRD) were discussed. TEM micrographs revealed that though untreated WM particles were within the nanometer scale, however showed incremental reduction in size via silane treatment. Mechanical parameters, thermal stability, FTIR and scanning electron microscopy (SEM) of the advanced NBR and SBR nanocomposites have been studied. Filler loading with 5 wt% led to remarked improvement in the tensile strength (TS), modulus of elasticity (M-100), and tearing strength of the NBR nanocomposite samples. Meanwhile, elongation at break of SBR nanocomposites exhibited regressive behavior. Thermal stability testing of pristine NBR and SBR specimens demonstrated adverse features by compounding with untreated and treated waste nanomarble. Furthermore, gamma irradiated NBR nanocomposites reinforced with TWM indicated appreciable development at all thermogravimetric stages. Whereas, irradiation of SBR nanocomposites with a gamma integral dose of 100 kGy resulted in slight enhancement in thermal stability.