Synthesis of new hydrogels by copolymerization of poly(2-methyl-2-oxazoline) bis(macromonomers) and N-vinylpyrrolidone

New non-ionic hydrogels were synthesized by radical homopolymerization of vinyl end-functionalized poly(2-methyl-2-oxazoline) bis(macromonomers), or by radical copolymerization of these bis(macromonomers) with N-vinyl-2-pyrrolidone (NVP). The poly(2-methyl-2-oxazoline) bis(macromonomers) were synthesized through "living" cationic ring-opening polymerization of 2-methyl-2-oxazoline (MeOXA), using, simultaneously, the known "initiating" and "end-capping" method for synthesis of macromonomers. Chloromethyl styrene was used as initiator and N-(4-vinylbenzyl)-piperazine was used as the terminating agent. Well defined poly(2-methyl-2-oxazoline) bis(macromonomers) were obtained with P_n = 4, 11, and 17. The hydrogel structures were characterized by high-resolution magic angle spinning NMR technique and their solvent absorption capacity was tested by swelling experiments in different solvents. The bis(macromonomers) were characterized by NMR spectroscopy and gel permeation chromatography.