Controlled polymerization of methyl methacrylate with prophinatocobalt(II)catalysts in supercritical carbon dioxide

[GRAPHICS] We report the successful controlled polymerization of methyl methacrylate i n the presence of the catalytic chain transfer agents 5,10,15,20-tetrapheny lporphinatocobalt(II) and 5,10,15,20-tetra(pentafluorophenyl)porphinatocoba lt(ll) (CoTFPP) in supercritical carbon dioxide (scCO(2)). Low molecular we ight polymers with narrow polydispersities have been prepared both at low a nd high monomer conversion and the chain transfer constant is found to be 1 .3 x 10(3), which is comparable to the value obtained in traditional solven ts.