A series of densely grafted star-and comb-shaped molecular brushes composed of polystyrene, poly (tert-butyl acrylate), and poly (N-isopropylacrylamide) were prepared by atom transfer radical polymerization (ATRP) using either cyclotriphosphazenes or polyphosphazenes as initiators. The initiators were prepared by the introduction of a free hydroxyl group into the side chains of a phosphazene cyclic trimer and polymer, followed ...