Submitted to: Annual Meeting and Expo of the American Oil Chemists' Society
Publication Type: Abstract Only
Publication Acceptance Date: 5/13/1998
Publication Date: N/A
Technical Abstract: Biodegradable lubricants present an opportunity for vegetable oils to be utilized at large scale. Biodegradability is a property of basestock, which amounts to more than 80% of lubricant. Volatility, oxidative stability, oxypolymerization tendencies and low temperature properties of vegetable oils were tested to compare them against other biodegradable basestocks, such as polyalphaolefins (PAO), isoalkyl adipates and polyol oleates. Test to Investigate Liquid Oxypolymerization of Nonvolatile Analytes (ILONA) at 150C and 175C showed that vegetable oils are essentially nonvolatile, whereas other basestocks exhibited evaporation in excess of 20%wt. ILONA demonstrated that oxidative stabilities of vegetable oils were much lower than those of PAO or adipates. However, vegetable oils with minor contents of methylene interrupted polyunsaturated fatty acids, such as meadowfoam or high oleic sunflower, showed better resistance to oxypolymer formation than commercial oleates in ILONA. Pour point and cold storage at -25C tests showed poor performance of vegetable oils at low temp. Chemical modification is necessary to overcome the performance deficiencies. Elimination of methylene interrupted fatty acids can increase oxidative stability and reduction of molecular weight through interesterification can improve low temperature properties.