Submitted to: Society of Tribologists and Lubrication Engineers
Publication Type: Proceedings
Publication Acceptance Date: 12/15/2011
Publication Date: 5/6/2012
Citation: Harry O Kuru, R.E., Biresaw, G., Cermak, S.C. 2012. Characteristics of polyhydroxy milkweed triglycerides and their acylated derivatives in relation to lubricity. Proceedings of the Society of Tribologists and Lubrication Engineers Annual Meeting & Expo. p. 112.
Technical Abstract: Industrial lubricants are derived from non-renewable petroleum-based resources that can cause pollution due to poor degradation. Seed oils, however, are both renewable and readily biodegradable, but have lower thermal stability and shorter shelf-life. This drawback can be overcome and yet retain the inherent biodegradability by appropriate derivatization of the oil. In this regard, we have investigated milkweed oil to assess its suitability as an industrial lubricant. The milkweed plant of the family Asclepiadaceae L, comprising genera which include the common milkweeds, Asclepias syriaca, A. speciosa, A. tuberosa, etc., were investigated. The oil contains highly unsaturated C-18 triglycerides. Modification generates polyhydroxy triglycerides exhibiting high viscosity and excellent water retention. Further modification was conducted via acyl substitution of varying chain lengths. Effect of chemical modification on oxidative stability, film thickness, friction and wear is discussed.