Understanding the Effect of Graphene Nanoplatelet Size on the Mechanical and Thermal Properties of Fluoroelastomer-Based Composites

This study presents a comprehensive evaluation of the behavior of fluoroelastomer (FKM) compounds reinforced with graphene nanoplatelets of various sizes such as 15 μm (GN15) and 5 μm (GN5). The study evaluates the mechanical, dynamic mechanical, thermal, wetting, and photothermal properties of the compounds when irradiated with an 808 nm laser. The results demonstrate that the size of the graphene nanoplatelets significantly impacts the mechanical properties, with smaller sizes exhibiting a stronger reinforcing effect compared to larger nanoplatelets. Additionally, clear evidence of an influence on dynamic mechanical properties was observed, particularly through the broadening of the damping factor (tan δ) peak. This suggests modifications to the material's viscoelastic behavior. Regarding the photothermal response, it was found that smaller nanoplatelets (GN5) dispersed in the rubber matrix allow higher temperatures to be reached and thermal equilibrium to be achieved more efficiently under irradiation. Overall, the results suggest that FKM compounds containing graphene nanoplatelets can attain high temperatures with low-energy infrared irradiation. This makes them promising materials for technological applications in extreme environments, such as the Arctic, high mountains, or space, where materials with controlled thermal responses and high mechanical performance are required.