FLUOROCARBON HYDROCARBON INTERACTIONS AND FRICTIONAL SURFACE FORCES

Alumina-adsorbed hydridosiloxane polymers are used as a ''base'' for f urther chemical modification and determination of intersurface frictio nal coefficients. The stability of this base layer is found to be part icularly sensitive to the presence of moisture. Sedimentation experime nts suggest that the final densities of compacts produced from hydrido siloxane-coated alumina particles are independent of the range of mole cular weights used in this study. Subsequent reaction of the base laye r with silanol-terminated trifluoropropylsiloxane and polydimethylsilo xane tails yielded considerable differences in sediment density and ch aracter in spite of similar molecular weights. Use of a frictional sur face forces apparatus suggests that this phenomenon is not due to a fr ictional or lubricative effect induced by the fluorine-containing comp onent.