We have grafted end-functionalised polystyrene bonds via a covalent bond on hydrogen-terminated silicon and on silica surfaces. The reaction is carried out using a polymer melt. The grafting density of the brushes prepared in a polymer melt is much higher than those obtained by reaction in solution. The reaction of the vinyl-terminated polystyrene takes place at the surface under very mild conditions. The preparation of both brushes is a versatile 'one pot' synthesis involving only the substrate and the vinyl-terminated polystyrene. The method also allows bimodal (mixed) brushes to be prepared from a suitable mixture of precursors. (C) 2003 Elsevier Science B.V. All rights reserved.