Accession Number : AD0726685

Title :   The Coefficient of Friction of High Polymers as a Function of Pressure.

Descriptive Note : Final rept.,

Corporate Author : NAVAL RESEARCH LAB WASHINGTON D C

Personal Author(s) : Bowers,R. C.

Report Date : 16 JUN 1971

Pagination or Media Count : 17

Abstract : Frictional behavior of low-density polyethylene, high-density polyethylene, polypropylene, polyvinylidenefluoride, PTFE, ethylene-tetrafluoroethylene copolymers, and tetrafluorethylene-hexafluoropropylene copolymers is reported. The experimental values of the coefficient of friction for each polymer agreed well with the values calculated from the pressure/shear strength data, even when this data was extrapolated to higher or lower pressures. It is concluded that the coefficient of friction as a function of pressure can be determined from shear strength measurements, and conversely shear strength as a function or pressure can be estimated from friction measurements of thin films. In general, for thin polymer films, where pressures are usually high, the coefficient of friction will be determined almost entirely by the slope of the shear strength-vs-pressure curve. For bulk polymer specimens the coefficient of friction will be greatly influenced by the intercept on the shear strength axis of that curve and the hardness of the polymer. This accounts for the large difference in the frictional properties between bulk specimens of high-density and low-density polyethylene. (Author, modified-PL)

Descriptors :   (*LUBRICANTS, THERMOPLASTIC RESINS), (*POLYETHYLENE PLASTICS, FRICTION), (*VINYL PLASTICS, FRICTION), (*HALOCARBON PLASTICS, FRICTION), FILMS, PROPENES

Subject Categories : Lubricants and Hydraulic Fluids
      Plastics

Distribution Statement : APPROVED FOR PUBLIC RELEASE