Triboelectrification of wood with PTFE

Triboelectrification for a rolling contact between hardwood and softwood spheres and a polytetrafluoroethylene (PTFE) plane is studied. For a variety of experimental parameters, the saturation charge developed on the spheres was measured. The results are compared with those reported previously where PTFE spheres were rolled on wood planes. The observations suggest that different principles are involved in the two experimental situations; however, in both cases the saturation charge developed depends on the apparent area of contact.