The functionalized membranes are membranes modified with appropriate functional groups that introduce new membrane properties, affinity or catalytic, for improving the selectivity or creating an entirely novel separation function (Ulbricht 2006).
The usual surface modifications in the literature are the following: coating (Dickson et al. 1998), self-assembly (Luo et al. 2005), chemical treatment (Van der Bruggen 2009), plasma treatment (De Geyter et al. 2008), and surface graft polymerization (Belfer et al. 2004).
Adsorption/adhesion – the functional layer is only physically fixed on the base material; the binding strength can be increased via multiple interactions between functional groups in the macromolecular layer and on the solid surface.
Interpenetration via mixing between the added functional polymer and the base polymer in an interphase.