zinkdialkyldithiophosphat

Zinkdialkyldithiophosphate, often abbreviated as ZDDP, is an organosulfur compound commonly used as an additive in lubricating oils. Its primary function is as an anti-wear agent, forming a protective tribofilm on metal surfaces. This film reduces friction and wear, extending the lifespan of engine components. ZDDPs are characterized by a central zinc atom bonded to two dialkyldithiophosphate groups. The "alkyl" part refers to hydrocarbon chains, which can vary in length and structure, influencing the properties of the ZDDP. These variations allow for tailoring ZDDPs to specific applications and operating conditions. Beyond anti-wear properties, ZDDP also exhibits antioxidant and corrosion inhibiting characteristics. However, its phosphorus content can interfere with catalytic converters in gasoline engines, leading to reduced effectiveness and emissions control issues. Consequently, the concentration of ZDDP in engine oils has been reduced in modern formulations, particularly for vehicles equipped with catalytic converters. ZDDP is synthesized through a reaction involving phosphorus pentasulfide and an alcohol, followed by neutralization with zinc oxide.