Towards a Polymer-Brush-Based Friction Modifier for Oil

Abstract To meet the need for oil-compatible friction modifier additives that can significantly reduce energy consumption in boundary-lubrication regime, a macromolecular design approach has been taken. The aim was to produce lubricious polymer film on sliding surfaces. A series of readily functionalizable block copolymers carrying an oleophilic poly(dodecyl methacrylate) and poly(pentafluorophenyl various lengths synthesized by means reversible addition-fragmentation chain-transfer (RAFT) polymerization. used attach surface-active nitrocatechol anchoring groups polymer. friction-reduction properties these polymers were assessed with 0.5 wt% solutions hexadecane rolling-sliding macroscopic tribological tests. Block roughly equal moderate molecular weights more effective at reduction than all other architectures investigated. They also displayed lower coefficients glycerol monooleate—a commercially additive. film-formation ability examined using quartz-crystal microbalance dissipation (QCM-D), monitoring their adsorption onto iron oxide-coated QCM crystal. highest lubrication efficiency formed thin ~ 17 nm thickness crystal, indicating formation brush. Interferometric experiments same showed separating 20 nm, which is consistent QCM-D value, bearing mind compression adsorbed layers two surfaces during testing. Graphical