Rapid surface functionalization of poly(ethersulphone) foils using a highly reactive oxygen-plasma treatment

We present a study of the oxygen-plasma functionalization of polyethersulphone (PES). PES samples were exposed to a weakly ionized, highly dissociated oxygen plasma, with an electron temperature of 5 eV and a positive ion density of 8 x 10(15) m(-3), and its afterglow, in which the density of charged particles was negligibly low and the density of neutral oxygen atoms was 4 x 10(21) m(-3). The wettability of the samples was determined by measuring the contact angle of a water drop, while the appearance of the functional groups on the surface of the samples was determined using high-resolution conventional XPS. The samples were saturated with surface functional groups, both in the plasma and in the afterglow region, after 1 s of treatment time. The results are explained by the high flux of oxygen atoms on the sample surface and the characteristics of the oxygen plasma. Copyright (c) 2007 John Wiley & Sons, Ltd.