Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 1/15/2005
Publication Date: 9/12/2005
Citation: Adhvaryu, A., Sharma, B.K., Erhan, S.Z. 2005. Process development and tribochemical evaluation of seed oil based antiwear/antifriction additive. Meeting Abstract. Interpretive Summary:
Technical Abstract: Antiwear/antifriction additives enhance the ability of lubricants to withstand mechanical stresses of interacting surfaces under boundary lubrication conditions. The majority of lubricants and additives currently used are petroleum based and are toxic to environment; making it increasingly difficult for safe and easy disposal. There has been an increasing demand for 'green' lubricants and lubricant additives in recent years due to concerns about lubricants lost to the environment and increasingly strict government regulations controlling their use. The triacylglycerol structure of seed oils is amphiphilic in character which makes them an excellent candidate for use as a lubricant or additive. In addition, triacylglycerol structures provide sites for chemical modification to improve on the existing technical properties such as thermo-oxidation, cold flow, and other tribochemical degrading processes. The antiwear properties of additives are as a result of tribochemical protective film formation. As a result, metal-to-metal contact and progression of pits and asperities on the metal surface are inhibited. It has also been observed that friction coefficient and wear rate are dependent on the adsorption energy and film strength of the lubricant components. In this work, seed oil structure was chemically modified to obtain a poly(hydroxy thioether) derivative. This compound can effectively function as antiwear/antifriction additive in industrial and automotive applications. This process retains the seed oil structure and its basic advantages (high flash point, viscosity index, lubricity, and eco-friendly nature). Different lubrication conditions were simulated using ball-on-flat and four-ball test geometry to compare the bio-additive molecules with commercially available products. Tribochemical phenomena occurring in such systems are also explained.