The research is about the bottom-up development of advanced lubricant coatings that are inspired by natural lubricating systems. Specifically, the project will develop new poly(ionic liquid) coatings and investigate their rolling and sliding frictional properties in contact with a swelling ionic liquid solvent. This system offers charged, comb-like polymer chains within a bound/mobile medium, much like natural lubricants, and a liquid with tailorable viscosity and swelling properties to fine tune the tribological performance. The approach of the research will be to employ surface-initiated ring opening metathesis polymerization to grow the lubricant coatings from both planar silicon (oxide) surfaces and silica microparticles. This method enables rapid polymer growth and the ability to tailor the ionic liquid side chain length, composition, and counter ion to investigate molecular-scale effects on the lubricating performance of the coatings. The most promising lubrication systems, based on sliding results, will be employed for the rolling lubrication of silica microspheres confined in both microchannels and hemispherical polymeric cavities.
If successful, this research will lead to new types of lubricated systems improving sliding and rolling lubrication systems. This will lead to greatly reduced friction and wear in microfabricated systems. Outreach will include the development of case studies from this research that will impact undergraduate classes, undergraduate research, and a week-long specialty course for gifted eight graders through the Vanderbilt Summer Academy. Students will learn to assemble coatings, measure their surface and tribological properties and connect these properties to basic intermolecular interactions. The research will also create a better understanding in high school by allowing a local high school teacher to participate in this research through a Research Experience for Teachers program.