Nicholas Szwaja
HW 5, Problem 4
Polymer Brushes
Reference :” Lubrication with Oil-Compatible Polymer Brushes”, Bielecki , Benetti, kumar, and Spence, 8
January 2012
A polymer brush provides surface modification strategy for friction and wear reduction in hard contact
under boundary lubrication conditions, specifically for a non-aqueous environment. The brush is
comprised of a densely grafted, surface tethered polymers in the presence of a good solvent attain a
brush-like, stretched configuration. Other scientists and engineers have investigated frication properties
of polymer brush and found that when immersed in a good solvent, they lead to substantial decrease in
frictional forces, resulting from the fluid like interfacial layer. The behavior of polymer brushes under
tribological stress depends on the way in which they are anchored to surfaces, their chemical and
physical state under the liquid, and the type and level of mechanical stresses within the contact zone.
Various experimental brushes have been tested using various polymers and various solvents. The
conclusion shows that polymer brushes submerged in poor quality solvent has a large increase in friction
and higher Hertzian contact pressure while higher quality solvent brought out the low friction properties
in the brushes.