"Living" free radical photopolymerization initiated from surface-grafted iniferter monolayers

A method for chemically modifying a surface with grafted monolayers of init iator groups, which can be used for a "living" free radical photopolymeriza tion, is described. By using "living" free radical polymerizations, we were able to control the length of the grafted polymer chains and therefore the layer thickness up to similar to 100 nm. Also, single-layer grafted block copolymers were obtained by subsequent polymerizations of styrene and methy l methacrylate monomers. The surface-grafted polymer and block copolymer la yers were evidenced by direct imaging methods (transmission and scanning el ectron microscopy) and by indirect surface characterization methods (contac t angle measurements, SFM, XPS, and IR). The ability to control the thickne ss of the grafted polymer as web as the synthesis of a grafted block copoly mer layer in a well-defined manner affirms the "living" character of the su rface-initiated free radical photopolymerization.