Influence of Organic Friction Modifiers on Surface Energy Properties in Polyalphaolefin (PAO) Blends
DOI:
https://doi.org/10.11113/jtse.v12.242Keywords:
Polyalphaolefins, Stearic Acid, Oleic Acid, Contact Angle, Friction, Wear.Abstract
The shift towards alternative fuels like hydrogen, ethanol, and other sustainable energy sources drives the need for high-performance lubricants to handle new thermal and chemical challenges. Synthetic polyalphaolefins (PAOs) are commonly utilised due to their thermal stability, high viscosity index, and reliable low-temperature flow. This study investigates the impact of organic friction modifiers—oleic acid (OA) and stearic acid (SA)—on PAO-based lubricants' tribological and interfacial characteristics. Blends containing 0.1–0.5 wt% OA or SA were tested. Contact angle measurements indicated that the 0.3 wt% OA blend significantly improved surface wettability, achieving the lowest contact angles on glass and steel surfaces. Surface energy analysis revealed decreased surface tension and better adhesion for the 0.3 wt% OA blend. Friction testing showed that the 0.3 wt% OA blend recorded the lowest coefficient of friction; however, wear resistance largely remained unaffected. These findings indicate that OA improves frictional performance in PAO lubricants, presenting a promising avenue for optimising formulations for future energy systems.
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