Cylindrical polymer brushes with densely grafted cyclic side-chains are synthesized via the grafting-onto method.The structure and composition of the polymers are well characterized.Linear polynorbornylene derivative (l-PND) backbones containing alkynyl groups are prepared by ring opening metathesis polymerization (ROMP)

and cyclic poly(tert-butyl acrylate) side-chains (c-PtBA) containing azide groups are synthesized by the combination of atom transfer radical polymerization (ATRP) and copper catalyzed azide-alkyne cycloaddition (CuAAC) reaction.Then

the cyclic side-chains are grafted densely onto the backbone by CuAAC reaction to form a cylindrical polymer brush.The structures of the polymers were characterized by 1H-NMR

gel permeation chromatography (GPC) and infrared (IR) spectroscopy.The obtained polymer brush has a long backbone of 400 degree of polymerization.The densely grafted side-chains lead to extension of the backbone.A single molecule of the polymer brush shows a wormlike (cylindrical) morphology observed by the atomic force microscopy (AFM).The length of the polymer brush is 200 nm

and the diameter is 30 nm.The polymer brush with cyclic side-chains is observed as a wormlike molecule for the first time

which has great reference value to study the influence of the topological structure (backbone and side-chains) on the morphology of the polymer brushes.