A multitechnique analysis of the outermost layers of the Teflon PFA surface

Fluoropolymers are notoriously difficult to metallize. In order to ascertain the role of the substrate surface, the surface chemical structure of a representative fluoropolymer has been determined. Three techniques have been used to study the outer surfaces of the extruded fluoropolymer film, Teflon PFA. These techniques are: high-resolution electron energy-loss spectroscopy, phase-sensitive photoacoustic Fourier-transform infrared spectroscopy and time-of-flight secondary ion mass spectroscopy. These complementary techniques confirm that the extrusion process introduces a small amount of outer surface contamination, probably through the reaction of the hot extrudate with the atmosphere immediately on exiting the film-forming die.