| Abstract
| - Seed oils are renewable and an environmentally friendly alternative to mineral based oils in lubrication andother important industrial applications. They are generally triesters having a complex distribution of fattyacid (FA) chains. All the physical and chemical properties of seed oils are dependent on their FA distribution,composition, and additional functional groups in the chain structure. In this work, various seed oils are studiedfor their boundary lubrication properties using the Langmuir adsorption model for their possible use as industriallubricants. This information can be used to design suitable lubricant molecules that will have optimum structurefor effective metal adsorption as well as exhibit excellent boundary lubrication properties. The free energy ofadsorption (ΔGads) of cottonseed, canola, olive, and meadowfoam oil is investigated in boundary lubricationregime using steel ball-on-disk geometry. Adsorption values were compared with monoesters with varyingchain lengths. It was observed, based on computed ΔGads, that molecular polarity, hydrocarbon chain length,and relative distribution of unsaturation in the FA chain can affect adsorption on the metal surface. Statisticalanalysis on FA distribution and ΔGads was helpful in making a generalized assumption on adsorption behavior.The results are consistent with theoretical assumptions on surface adsorption as a function of molecular structure.
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