AVS 53rd International Symposium
    Surface Science Thursday Sessions
       Session SS2+NS+TF-ThA

Paper SS2+NS+TF-ThA4
Design of Environmentally Friendly Lubrication Systems through Surface Grafting of Ultrahydrophilic High-density Polymer Brushes

Thursday, November 16, 2006, 3:00 pm, Room 2004

Session: Tribology
Presenter: A. Takahara, Kyushu University, Japan
Authors: A. Takahara, Kyushu University, Japan
M. Kobayashi, Kyushu University, Japan
K. Ishihara, The University of Tokyo, Japan
A. Suzuki, Toyota Motor Co., Ltd., Japan
M. Kaido, Toyota Motor Co., Ltd., Japan
Correspondent: Click to Email
The hydrophilic polymer brushes of poly(2,3-dihydroxypropyl methacrylate) (poly(2)) and poly(2-methacryloyloxyethyl phosphorylcholine) (poly(3)) were prepared by surface-initiated atom transfer radical polymerization of (2,2-dimethyl-1,3-dioxolan-4-yl)methyl methacrylate (1) and (3) on the initiator- immobilized silicon wafer. A large water contact angle hysteresis was observed for poly(2). Extremely low water contact angle and low contact angle hysteresis of poly(3) against water were observed. Neutron reflectivity measurements at water/poly(3) brush interface reveled that the poly(3) is highly stretched to the bulk water phase. Frictional properties of the poly(2) and (3) brushes were characterized by sliding a glass ball probe on the polymer brush surfaces in various solvents under the load of 0.49 N at a sliding velocity of 90 mm/min. Friction coefficient of poly(3) brush was lower than that of poly(2) in water. This can be ascribed to the presence of phosphorylcholine in poly(3). Further low friction coefficient was observed, even in air, by sliding a poly(3) brush immobilized glass ball against poly(3)-immobilized silicon wafer.