Influence of Polyalkylmethacrylate Viscosity Index Improvers on the Efficiency of Lubricants

The efficiency of lubricated machine elements such as transmissions, crankcase engines, and hydraulic pumps depends strongly on the friction properties of the lubricant employed. For the design of modern, highly efficient lubricants it is thus essential to understand the influence of the components of the lubricating fluid in terms of film formation and consequent friction.

The influence of Polyalkylmethacrylate (PMA) Viscosity Index Improvers on those important parameters has been studied by means of optical interferometry and friction testing. Low friction coefficients and positive contributions to the boundary film thickness of the lubricant were obtained when composition and architecture of the polymeric VII were appropriately designed.

Results from bench tests measuring the oils' equilibrium temperature in a bearing (ARKL test) and their torque transmitting efficiency (FZG gear test) indicate that PMA Viscosity Index Improvers provide a tool to formulate lubricants with tailored friction properties and improved efficiency.