Development and characterization of a wettable surface modified aromatic polyethersulphone using glow discharge induced HEMA-graft polymerisation.

The aromatic polyethersulphone (PES) is a well known polymer for the preparation of membranes with excellent thermal stability and chemical resistance. The disadvantage of PES-membranes is their hydrophobic character, which in contact with protein containing solutions leads to high protein adsorption and as a consequence to deterioration of membrane properties. In this report the surface modification of PES by means of glow discharge induced grafting of 2-hydroxyethyl methacrylate (HEMA) is described. Graft polymerisation creates a largely wettable layer of poly(2-hydroxyethyl methacrylate) (PHEMA) on the surface of PES. This has been shown by contact angle measurements using the Wilhelmy plate method. Chemical characterization is carried out by means of X-ray photoelectron spectroscopy (XPS) and infrared spectroscopy/attentuated total reflection (FTIR-ATR). The influence of storage conditions on the surface properties of modified PES samples has been investigated after storage in vacuum, water, and air.