The cationic ring-opening polymerization of 2-methyl-2-oxazoline (MOx) using iodine in system was reported Uncolored polyoxazolines were produced in spite of the use of iodine initiator, well-known dye molecule Low molecular weight asymmetric telechelic polyoxazolines carrying an acetylimine headgroup and an oxazolinium end group were synthesized, with a good control over the molecular weight NMR and MALDI-TOF experiments allowed the full determination of the chemical structures of the produced poly(2-methyl-2-oxazoline)s, notably with the acetylimine headgroup, explained by spontaneous alpha-H1 elimination Finally, to our knowledge, we reported the first detailed mechanism of cationic ring-opening polymerization of 2-methyl-2-oxazoline in acetonitrile according to UV experiments An ionic-type mechanism was involved With the dissociation Of molecular iodine to active initiating species