Brush macromolecules having poly (l-lactide)(PLLA) and poly (styrene)(PS) side chains were prepared on the backbone of partially esterified poly (2-hydroxyethyl methacrylate)(PHEMA) by using a combination of atom transfer radical polymerization (ATRP) and ring-opening polymerization. The number-average degrees of polymerization of PLLA side chains and PS side chains were determined by 1H NMR spectroscopy, and the ...