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A comparative study on two nanocomposites based namely on acrylonitrilebutadiene (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.

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The present study aims to investigate the influence of modified zinc oxide nanoparticles content on the physico-chemical properties of sawdust/epoxy composite specimens. The results show an improvement in the mechanical properties in terms of flexural strength, impact strength, and hardness with increasing the modified zinc oxide nanoparticles content up to 5%, while the physical properties such as water absorption and thickness swelling percentages are decreased directly with increasing the content of modified zinc oxide. In addition, the behavior of irradiated composite specimens containing 5% modified zinc oxide nanoparticles at different gamma-irradiation doses, 10, 30, and 50 kGy, has been studied. The results indicate that the irradiated composite specimens at 10 kGy have better physico-chemical properties as compared to the unirradiated specimens. Furthermore, the antimicrobial properties of composite specimens containing 5% modified zinc oxide at 0 kGy and 10 kGy against different plant pathogenic fungi and bacteria are also discussed. The results demonstrate that the growth activity of fungi and bacteria on the composite specimens are reduced to a great extent as compared to the control composite specimens (0% of zinc oxide nanoparticles). Thermal behavior and morphology of the prepared specimens are detected using thermogravimetric analysis and scanning electron microscopy technique.