Toward the design of LPEI containing block copolymers: Improved synthesis protocol, selective hydrolysis, and detailed characterization

Abstract The synthesis of poly(2‐ethyl‐2‐oxazoline)‐ b ‐linear poly(ethylenimine) (PEtOx‐ b ‐LPEI) copolymers by selective basic hydrolysis of PEtOx‐ b ‐poly(2‐ H ‐2‐oxazoline) (PEtOx‐ b ‐PHOx) is described. For this purpose, an easy method for the preparation of the 2‐ H ‐2‐oxazoline (HOx) monomer was developed. Based on the microwave‐assisted polymerization kinetics for this monomer, PEtOx‐ b ‐PHOx copolymers were prepared. Subsequently, the block copolymers were selectively hydrolyzed to PEtOx‐ b ‐LPEI under basic conditions. The success of the polymerizations and subsequent post‐polymerization reactions was demonstrated by 1 H NMR spectroscopy and MALDI‐TOF‐MS investigations of the obtained polymers. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012