The polymer nitrile N-oxide containing poly(ethylene glycol) (PEG) skeleton PEG-CNO was synthesized via a stepwise reaction. The catalyst-free click reaction of PEG-CNO with terminal CvC bond-tethering compounds afforded the corresponding diblock and multi-arm star polymers in high yields. The click reactions under solvent-free conditions resulted in significant rate acceleration and high yields of the polymers.