ADHESION OF POLYTETRAFLUOROETHYLENE

Nucleation and crystallization of polytetrafluoroethylene in contact with gold produces a surface region of high mechanical strength in the polymer as evidenced from the strong adhesive joints prepared with a conventional epoxy adhesive. In addition, the wettability of the gold-nucleated polytetrafluoroethylene, after dissolution of the gold, is vastly improved. The critical surface tension of wetting increases from 18.5 dynes/cm to 40 dynes/cm, indicating an increase in the surface density of the gold-nucleated polymer. We conclude from this study, that the occurrence of the normal weak boundary layer on polytetrafluoroethylene is a consequence of the morphology of the surface region and is therefore influenced by the method of preparation. © 1969 Taylor & Francis Group, LLC. All rights reserved.