Copper (Cu) nanoparticles have attracted considerable attention because of their applications in many different fields. In this paper, Cu particles have been produced by means of a pulse laser ablation (PLA) process to ablate Cu metallic target submerged in two different mediums, water, and ethanol. The laser ablation process was occurred at energy by 900 and 700 mJ with wavelengths of 532 and 1064 nm. The UV visible spectrum was also characterized to investigate the optical properties. The atomic force microscope (AFM) and scanning electron microscope (SEM) were used to detect the nanoparticles of Cu. The results showed that the Cu nanoparticles could be prepared successfully in ethanol media at both laser energies 900 and 700 mJ for 532 and 1064 nm wavelength. Peak at 575 nm appeared in the U.V visible spectrum which indicates the formation of Cu nanoparticles. Furthermore, there is a slight chance for preparation of Cu nanoparticles in water media owing to the incidence of Cu oxides instead of Cu nanoparticles.

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Improving the mechanical properties of polymeric materials has become necessary for the mechanical designer, especially by using nano materials due to easy and wide use. Therefore, in this research, silica nanoparticles (SiO2NPs) were used to improve the tensile, creep resistance, and hardness of epoxy. The volumetric ratios of SiO2NPs (0.5, 1, 1.5, and 2%) were mixed by using a magnetic starrier and ultrasound mixer then poured into a mold. The tensile, creep resistance, and hardness properties of the resulting composites were studied. The microstructure was investigated using a field emission scanning electron microscope (FESEM) and x-ray diffraction devices. The results showed that the best Young Modules and the ultimate stress were obtained at (1.5%) of SiO2NPs, while the best creep strain improvement was at (1%) of SiO2NPs. The SEM and X-ray diffraction results showed homogeneous silica nanostructures.

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The research covered most of the recent scientific research related to strengthening the natural rubber and improving its physical properties. The swelling properties played a substantial role in decreasing the efficiency of the elastomer compounds as a result of immersing or contacting these compounds with organic solvents. Using nanoparticles for inorganic fillings is essential with a view to expanding the industrial applications of natural rubber Nano-composites. The research covered the latest methods that researchers have used to reduce rubber swelling to the lowest levels. The paper discussed the relationship between swelling properties and mechanical, electrical, curing, and morphology properties. The research also discussed the relationship between swelling properties and the concentration of the filter used to harden the rubber matrix, the swelling capacity, and the type of Nano-composite. All results, which discussed by previous studies showed that improving the thermal, electrical and mechanical properties of the Nano-composites of natural rubber leads to a reduction in the swelling problems of the natural rubber compound, and that selecting or modifying the properties of the filler material gives encouraging and strong results towards reducing the rates of swelling.