STRUCTURE-PROPERTY RELATIONSHIPS IN THIN SOLID POLY(METHYL METHACRYLATE) BOUNDARY FILMS

The interface properties of boundary films are commonly characterized by the measurement of the interface shear stress, tau, which is define d as the functional force per unit area of contact. The parameter tau has been observed to be a strong function of seueral contact mechanica l variables which Include the contact pressure, the temperature, the s liding velocity and the contact time. tau is also found to be a strong function of the processing methods used In the preparation of polymer films. It is this facet of the functionality of tau that is pursued i n the present paper with an emphasis upon the apparent ductile or brit tle lubrication modes, the locus of the shear zone and the molecular a rchitectures which are responsible for these resultant lubrication mod es.