Chemical and physical modification of fluoropolymer surfaces for adhesion enhancement: A review

The primary goal of surface modification of fluoropolymers is to improve adhesion to these low surface energy materials. Both classical methods and newer processes have been used as a means to this end. Various methods of modifying fluoropolymer surfaces include wet chemical etching, elec- trochemical reduction, grafting, application and removal of metals, ion and electron beam techniques, and plasma modification. In addition to the modification procedure, it is necessary to evaluate the effectiveness of the chosen method by subsequent analysis of the modified surface. Physical analytical methods include contact angle and wettability measurements, lap shear and composite tensile shear strengths, peel strengths, and surface topographical determinations. Chemical analyses used include infrared, Raman, Rutherford backscattering, ultraviolet-visible, wide angle X-ray scattering, X-ray flu- orescence, and X-ray photoelectron spectroscopies as well as thermal desorption mass spectrometry. Each of the modification methods, with results of the subsequent chemical or physical analysis, will be discussed. © 1989 Taylor & Francis Group, LLC.