Investigation of anti-wear additives for synthetic esters

Antiwear (AW) properties of phoshphonic acid derivatives for trimethylolpropane (TMP) esters were investigated under boundary conditions. AW effect of dialkyl phosphonates depends on polarity of base fluid. They provide good AW performance in less polar TMP esters, whereas their AW effect is not sufficient in polar TMP esters. Amine sails of phosphonic acid were developed as new AW additive system for TMP esters. They provide excellent AW performance even in polar TMP esters.