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Developments of nanoparticle reinforced plastics are of growing interest towards the emergence of new materials which enhance optimal utilization of natural resources and particularly of renewable resources. The effects of nanoparticles as fillers in glass-epoxy composite systems on the mechanical and tribological properties have been discussed in this article. The mechanical properties such as tensile strength, impact strength, flexural strength, and hardness have been studied in accordance with ASTM standards. The composites employed in the study have been fabricated using hand lay-up technique. By varying notch radius impact strength is studied. The clay and silica used in the present system were treated with 3-aminopropyltriethoxysilane. The effect of variants in sliding speed, time and applied load on the wear behavior of polymer nanocomposites is studied by measuring the weight changes and observing the surface features using scanning electron microscope. In the experiments with wear test pin having flat face in contact with hardening rotating steel disc, sliding speed, time and loads in the range of 640-1000 RPM, 300-900 s and 5-25 N respectively was used. It is observed that wear rate increases with increasing applied load, time and sliding speeds.

Nitrile butadiene rubber (NBR) is a polymer widely used in pipe fittings as a sealing and damping element. The performance of the polymer materials degrades with time and temperature. The present work emphasizes the thermal degradation of NBR materials using thermogravimetric analysis (TGA) at heating rates of 5, 10, 15, and 20 °C min−1 in a controlled nitrogen environment. Model-free methods, namely the Kissenger, Kissinger-Akahira-Sunose (KAS), and Ozawa-Flynn-Wall (OFL) approaches, are used to determine the kinetic activation energy and frequency factor. The obtained values were used to calculate the lifetime of virgin NBR and the remaining life of naturally aged NBR. Fourier-transform infrared spectroscopy (FTIR) was used to detect changes in the functional groups of the NBR material with age. From the experimental data, it is concluded that virgin NBR has better thermal stability than naturally aged NBR. Furthermore, the activation energy of NBR is temperature-dependent, and oxidative aging has a significant impact on the degradation of kinetic parameters. At lower conversion rates, the activation energy of virgin NBR (79.39 kJ mol−1) and aged NBR (78.25 kJ mol−1) are almost the same, while at increased conversion rates, virgin NBR (529.77 kJ mol)−1 has higher activation energy than aged NBR (280.15 kJ mol−1).

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