Laser Photoluminescence Spectroscopy of the Subsurface Microstructure in a Nafion Polymer Membrane in Deuterated Water

The paper describes experiments in exposing the surface of a water-swollen Nafion polymer membrane to near ultraviolet radiation at grazing incidence. Ultraviolet radiation caused the surface of the Nafion polymer membrane to photoluminesce in a specific spectral range. This luminescence appears due to the presence of sulphonic acid groups at the ends of perfluorovinyl ether groups that form the polytetrafluoroethylen base of the Nafion membrane. We show that the photoluminescence signal is an important parameter for describing the process of polymer swelling in water

The study was supported by RFBR (grants no. 15-02-07586, no. 16-52-540001 and no. 1702-02-00214)

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