Preparation of block copolymer by atom transfer radical seeded emulsion polymerization

Poly(i-butyl methacrylate)-polystyrene block copolymer was successfully prepared in an aqueous medium by two-step atom transfer radical polymerization (ATRP), mini-emulsionand seeded-ATRP, in which ethyl 2-bromoisobutyrate\CuBr\4,4-dinonyl-2,2-dipyridyl initiator system was used. The block copolymer had narrow molecular weight distribution (Mw\Mn=1.1) and the number-average molecular weight measured by gel permeation chromatography agreed with the calculated value.