Tribological Properties of Thin Functionalized Polyethylene Film on Si With Chemical Modifications

A very thin functionalized polyethylene (fPE) film is successfully attached to Si substrate via a reactive benzophenone (Ben) layer. The presence of fPE promotes the wear durability of Si/Ben/fPE to 1000 cycles compares with 100 cycles of Si/Ben under 40 mN applied load and 500 rpm sliding speed. As an enhancement, perfluoropolyether (PFPE) is applied as a top mobile lubricant layer coated onto Si/Ben and Si/Ben/fPE and their tribological properties are evaluated under the same experimental conditions. A significant improvement in the wear durability is observed as Si/Ben/PFPE fails at 250,000 cycles and Si/Ben/fPE/PFPE does not fail till one million cycles. Si/Ben/fPE/PFPE can withstand the maximum applied load of 150 mN that provides the PV limit of 106.6 MPa ms⁻¹.