Abstract

This study aims to understand better the mechanical, thermal, and tribological behavior of silicone rubber nanocomposites. Graphite, exfoliated graphite, reduced graphene oxide, ionic liquid modified graphene oxide, silane-modified graphene oxide, fumed silica, and other fillers were used in this study. Adding graphene-based fillers to the silicone rubber matrix substantially improves the nanocomposite's mechanical, thermal, and tribological properties. The DMA and DSC analyses confirmed the improved polymer filler contact in the composite. When compared to the neat silicone rubber, the inclusion of graphite (20 phr) reduces the friction coefficient (40%) and the specific wear rate of QM significantly (50 percent). The modified Hummers process synthesized graphene oxide, and FT-IR, XRD, Raman, and XPS studies were performed to validate GO reduction. XRD, AFM, SEM, and TEM studies were used to investigate the dispersion and interaction of the filler in the polymer matrix. The tribological tests were conducted utilizing an ASTM G99-05 pin-on-disc tribometer to examine the effect of operating variables such as applied load, sliding velocity, and temperature. A single-layer graphene film functionalizes the polymer composite surface in the microstructure of graphene composites. Nanocomposites have a better filler distribution, according to scanning electron microscopy (SEM), transmission microscopy (TEM), and energy dispersive X-ray analysis (EDX). The mechanical properties of the nanocomposites, such as tensile strength and hardness, as well as the electrical and thermal properties, such as thermal conductivity, thermal degradation, and dielectric properties, are improved when compared to pure silicone rubber, which can be attributed to the improved distribution of the nanofillers. The composite's worn surface morphology exhibits a smooth surface, indicating that the presence of fillers significantly reduced metal contact. The wear mechanism involves the formation of a lubricant film on the counter surface, which prevents the asperities from touching the composite surface. As a result, the friction coefficient and specific wear rate are reduced. In addition to having high permeability and strong temperature resistance, silicone rubber also has outstanding age resistance and electrical insulation. As a result, it is frequently utilised in a variety of industries, including automotive, textiles, electronics, medical field, sealants, hard ware and food storage.

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