Amphiphilic comb-shaped and comb-like statistical copolymers of oligo(ethylene glycol) methacrylate (OEGMA) and 1H,1H,2H,2H-perfluorooctyl methacrylate (FOMA) has been synthesized in supercritical carbon dioxide as solvent via free-radical copolymerization and block copolymers¹ were prepared using group transfer polymerization. The hydrophilic chain is based on methoxy-capped oligo(ethylene glycol) methacrylate (OEGMA), a branched analogue of PEO, and the CO₂-philic component is a perfluorooctyl methacrylate segment. The micellar characteristics of the statistical copolymers in water and chloroform were investigated by quasi-elastic light scattering and transmission electron microscopy. The size and morphologies of micelles were greatly influenced by statistical copolymer composition. In addition, the solubility of statistical copolymers and the formation of reverse micelles in CO₂ were described in terms of the cloud points. The comb-shaped copolymers could form stable reverse micelles at w_o=12