The invention relates to a process for coating a material surface comprising the steps of: (a) reacting the material surface with a compound of formula (1), wherein the variables are as defined in the claims; (b) reacting the so modified surface with a functional polymerization initiator having a functional group that is co-reactive to L2 or L2'; and (c) applying one or more different ethylenically unsaturated hydrophilic monomers or macromonomers to the bulk material surface obtainable according to step (b) and polymerizing said macromonomers, thereby providing a preferably hydrophilic surface coating onto the material surface. Composite materials obtainable according to the process of the invention have desirable characteristics regarding adherence to the substrate, durability, hydropholicity, wettability, biocompatibility and permeability and are thus useful for the manufacture of biomedical articles such as ophthalmic devices.