Microwave-Assisted Cationic Ring-Opening Polymerization of 2-Oxazolines: A Powerful Method for the Synthesis of Amphiphilic Triblock Copolymers

Hoogenboom, Richard; Wiesbrock, Frank; Huang, Haiying; Leenen, Mark A. M.; Thijs, Hanneke M. L.; van Nispen, Sjoerd F. G. M.; van der Loop, Michel; Fustin, Charles-Andre; Jonas, Alain M.; Gohy, Jean-Francois; Schubert, Ulrich S.

Abstract:

We report on the first successful example of the preparation of triblock copolymers via a cationic ring-opening polymerization procedure. A library of 30 triblock copolymers was prepared from 2-methyl-, 2-ethyl-, 2-nonyl-, and 2-phenyl-2-oxazoline in a single-mode microwave reactor. The polymers exhibited narrow molecular weight distributions and showed only minor deviations from the targeted monomer ratio of 33:33:33. The glasstransition temperature of the triblock copolymers spanned the range from 50 to 100 °C depending on the incorporated monomers. The micellization behavior was investigated for some amphiphilic triblock copoly(2- oxazoline)s containing two hydrophilic and one hydrophobic blocks. The size of the micelles was larger when the hydrophobic block is located at one end of the triblock copoly(2-oxazoline)s, as measured by atomic force microscopy and dynamic light scattering.

Year:

2006

Type of Publication:

Article

Journal:

Macromolecules

Volume:

39

Pages:

4719 - 4725