Styrene/ethyl methacrylate (SEMA) colloids were obtained by cocondensation at 77 K of the monomers with several metals such as Au, Pd, In and Sn. The colloids were polymerized with 2,2'-azoisobutyronitrile and dibenzoyl peroxide as radical initiators at 60 degrees C for 3.5 h. A viscosity average molecular weight (10(4) < M(v) < 10(5)) was obtained depending upon the metal used,The particle size of these clusters dispersed in the copolymers ranges from 20 to 31 Angstrom. The metal clusters are incorporated in the copolymers.