Electrification and electret effect in polymer friction

The authors suggest a mechanism of polymer electrification and electretization resulting from mechanical effects, based on the applicability of the fundamental laws of the electrostatic theory of adhesion. Application of the electron theory of disordered systems and surface states provides a deeper understanding of the suggested mechanism of electrification, particularly the existence of surface states and their filling with injected charge carriers on contact separation; an electric charge appears on polymer surfaces. The effect of the surface charge field is to redistribute the charge within the near-surface region; a spatial charge area (SCA) and a double electric layer are formed whose charge density and structure depend on surface state characteristics. During electrification and surface charge and SCA formation, polymeric materials get polarized in the field of the latter two phenomena and an electret state is formed whose parameters depend on the free injected charge carriers and the polarization