Atom transfer radical polymerization (ATRP) was applied to a novel synthesis of rod consisting of hyperbranched pendant chains-coil block copolymers. The procedure included the following steps: (1) esterification reaction of poly(ethylene glycol) methyl ether (PEO) with 2-bromoisobutyryl bromide (BIBB) yielded a PEO-Br macroinitiator, (2) ATRP method of 2-hydroxylethyl methacrylate (HEMA) using PEO-Br provided PEO-block-poly(2-hydroxyethyl methacrylate) (PHEMA) block copolymers, (3) esterification of PEO-block-PHEMA with BIBB yielded block-type polyinitiator, and (4) ATRP of HEMA-Br inimer using block-type polyinitiator provided coil-rod (consisting of hyperbranched pendant chains) block copolymers. (c) 2008 Wiley Periodicals, Inc.