Submitted to: Society of Tribologists and Lubrication Engineers
Publication Type: Abstract Only
Publication Acceptance Date: 12/13/2010
Publication Date: 5/15/2011
Citation: Sharma, B.K., Doll, K.M., Erhan, S.Z. 2011. Modified vegetable oils-based lubricant emulsions [abstract]. Society of Tribologists and Lubrication Engineers Annual Meeting. p. 136.
Technical Abstract: Lubricants made from vegetable oils represent only a small section of the market today. Recent legislation, however, in both the United States and Europe, could begin to brighten their prospects due to their eco-friendly and biodegradable character, unlike petroleum oil-based products. In order to understand the effect of chemical modification, vegetable oils with different modifications were studied as base oils in lubricant emulsions. Vegetable oils evaluated were epoxidized vegetable oil, heat modified vegetable oil, castor oil, soybean oil, methyl soyate, and 2-ethylhexyl epoxy soyate. A series of different surfactants were studied in order to obtain emulsions suitable for lubrication applications. The epoxidized oils were found to form more stable emulsions, utilizing different surfactant systems, whereas only Brij® 30 and a modified Surfonic® MES 530 were able to stabilize soybean oil for 1 week under our test conditions. Overall, the best surfactants were the ones with an HLB value slightly above 9. The droplet size of emulsions made with surfactant, compared to those made without, showed the expected trend with submicron droplets formed only when surfactant was used. Finally, a lubrication study was performed showing that, even at only 1%, these vegetable oil emulsions can reduce friction nearly as well as their base oils. This information can be used to design suitable lubricant molecules that will provide good emulsion stability as well as lubricity.