Submitted to: Society of Tribologists and Lubrication Engineers
Publication Type: Abstract Only
Publication Acceptance Date: 10/3/2003
Publication Date: 5/20/2004
Citation: Isbell, T. 2004. Directed synthesis of base oils that overcome traditional vegetable oil shortcomings. Society of Tribologists and Lubrication Engineers.
Technical Abstract: Vegetable oils offer unique advantages over petroleum derived products for lubricity and biodegradability. However, poor cold temperature performance and oxidative stability have remained an issue for vegetable oils. High oleic oils have improved oxidative stabilities but still fall considerably short of most commercial lubricants in the market. Furthermore, most attempts to improve the performance of vegetable oils has been through additive packages or blending with synthetic oils with limited improvement in performance. We attacked the poor performance problem of vegetable base materials by chemically modifying the weak structural aspects of a vegetable based material, unsaturation and linear alkyl chains. Using an acid catalysis, oleic acid was condensed with a range of fatty acids to form estolides which were esterified with 2-ethylhexanol insitu. The iodine value of the estolides ranged from 0 to 45 where as the starting material had an iodine value of 85. Typically materials with low iodine value give good oxidative stability and bad pour points. However, estolides with low iodine value gave pour points from -30 to -42 deg C and RBOT times greater than 400 minutes. The estolides also maintained good lubricity and biodegradability that were inherent to the starting vegetable oils.