Polymerization of methyl methacrylate initiated by eerie ammonium nitrate in combination with poly(glycidyl azide)-diol was investigated in aqueous nitric acid. Poly(methyl methacrylate)-b-poly(glycidyl azide) copolymer was obtained. Block copolymer yield was increased using tetrabutyl ammonium hydrogen sulphate as a surfactant. The effect of nitric acid, eerie ions and diol concentration on the block copolymer yield was investigated. Block copolymers were characterized using GPC,H-1-NMR, FTIR, DSC, TGA and fractional precipitation methods. (C) 2001 Elsevier Science Ltd. All rights reserved.