2-Ethyl-2-oxazoline undergoes cationic ring opening graft polymerization using tosylated cellulose nanowhisker as macroinitiator.2-Ethyl-2-oxazoline (EtOx) was used in synthesis of block copolymers of EtOx and styrene by cationic ring-opening polymerization and atom transfer radical polymerization. 2-Ethyl-2-oxazoline undergoes cationic ring opening graft polymerization using tosylated cellulose nanowhisker as macroinitiator. 2-Ethyl-2-oxazoline (EtOx) was used in synthesis of block copolymers of EtOx and styrene by cationic ring-opening polymerization and atom transfer radical polymerization.