2013 Annual Report
1a.Objectives (from AD-416):
Synthesize, characterize and develop new biobased molecules for use as components of biobased lubricants. Initial work will focus on novel oleochemical-based ethoxylated oils synthesized at a collaborator laboratory. Other functional groups (e.g., amides and esters) will be synthesized and investigated later in the program.
1b.Approach (from AD-416):
Novel molecules will be synthesized and characterized in the labs of colleagues in Poland; evaluated for various tribological characteristics by colleagues in Poland, Lithuania and ARS; formulated for specific lubrication applications and tested at ARS and collaborator labs.
ARS scientists in the Bio-Oils Research Unit at the USDA-ARS National Center for Agricultural Utilization Research in Peoria, Illinois, in collaboration with scientists at the Technical University of Radom, investigated alkyl polyglucosides (APGs) as multi-functional additives for water-based metalworking fluids. Water can be used as an ecological lubricant base if it is possible to select additives which can beneficially modify its tribological and corrosion properties. Additionally, those additives should not be harmful to human health and the natural environment. These conditions limit or even eliminate the application of many additives used in traditional oil based lubricants, since they are insoluble in water and often toxic. APGs have been suggested as potential additives for improving lubricating properties of water because they: (1) are biodegradable, (2) do not have to be recycled, and (3) exhibit surface activity. APGs produce micelles at low concentrations and lyotropic liquid crystals at high concentrations. Two types of APGs differing in alkyl chain lengths and degrees of polymerization were investigated. Tribological tests were carried out using a ball-on-disc tribometer. The balls were made of steel, whereas the disc materials varied (steel, aluminium oxide, zirconium oxide, polymethylmethacrylate, and polyamide). The addition of APGs improved the lubricating properties of water. The relative decrease in friction and wear was a function of both the type of friction couple (ball and disc material combination) and on the kind of APG. Tribological test results were correlated with the surface activity of APGs and friction couples, such as the wettability of friction couples by aqueous APG solutions.
Collaborators will send samples of new ethoxylated vegetable oils to ARS for further evaluations.