The bulk polymerization of 2-(dec-9-enyl)-2-oxazoline (DecEnOx), a fatty acid-based monomer for the cationic ring-opening polymerization, is reported. Furthermore, under optimal conditions, namely microwave heating at 100 degrees C, the bulk copolymerization with 2-ethyl-2-oxazoline yielded well-defined copolymers. Due to its pendant alkene groups DecEnOx-based polymers possess the potential to be modified in efficient thiol-ene reactions. The functionalization with thiols, e. g., dodecanethiol and 2,3,4,6-tetra-O-acetyl-1-thio-beta-D-glycopyranose in "green'' solvents is demonstrated.