Tribological analysis of a novel lubricant additive: Pyrone esters

This work evaluates the friction and anti-wear properties under boundary lubrication of novel lubricity additives derived from 2-pyrone. Pyrone Esters (PEs) of varying carbon chain lengths were synthesized by reacting coumalic acid chloride with alcohols. Chemical composition was verified via NMR and mass spectroscopy while rheological behavior was characterized with a parallel plate rheometer. In comparison, a commercially available monoester was tested. For friction and wear testing, all additives were blended at 1% by weight into a mineral base oil. Neat oil served as the control. A custom reciprocating microtribometer and temperature controlled stage was used to generate wear scars and record the time-evolving friction response. Results showed that the addition of certain PEs reduced friction by up to 25% and mitigated wear by up to 60% in comparison to the neat oil. Subsequently, PE demonstrated its superb potential as an environmentally friendly base stock or lubricant additive.