Model for the Transfer of Polymer to Rough, Hard Surfaces

A process is described for the preparation of low density polyethylene (LDPE) doped with two percent dysprosium oxide for use in transfer experiments. The doping agent made it possible to use neutron activation analysis to measure transfer of LDPE to steel disks at levels of less than one microgram. A model is described which predicts the transfer of LDPE, PVC and PCTFE to within a factor of five or less to measured values of transfer. The model also predicts the penetration depth of the highest asperity into the polymer at which the material transferred fills up the valleys on the surface. The major significance of the model is that it does not require an experimentally determined wear coefficient to make the prediction of transfer. The model uses the normal load, yield strength of the polymer, the apparent area of contact, the bearing area curve for the surface, the polymer density, and the shear angle of the polymer to make the transfer prediction.