Monolayers of amphiphilic block copolymers via physisorbed macroinitiators

The synthesis of block copolymer monolayers at the surface of silicon oxide is described. Physisorbed monolayers of poly(epsilon-caprolactone) macroin itiators containing azo groups are used to start the radical chain polymeri zation of n-alkyl methacrylates in situ leading to the formation of amphiph ilic surface-attached block copolymers. The characterization of the attache d layers by surface plasmon spectroscopy, ellipsometry, infrared techniques , X-ray reflectometry, and water contact angle measurements is described. T he macroinitiator technique can be used to prepare hydrophobic layers on hy drophilic substrates and allows one to circumvent some major limitations of the block copolymer physisorption process, such as solubility problems of the block copolymer and intrinsic Limitations of the layer thickness.