writer：Zhang, N.; Huber, S.; Schulz, A.; Luxenhofer, R.; Jordan, R.
keywords：2-oxazoline, molecular brush, AFM, lower critical solution temperature
source：期刊
specific source：Macromolecules
Issue time：2009年

We report on the synthesis and characterization of cylindrical molecular brushes based on poly(2-oxazoline)s (POx). The dual-functional monomer, 2-isopropenyl-2-oxazoline (IPOx), was first converted to a poly(2-isopropenyl-2-oxazoline), backbone by free radical (PIPOxR) or living anionic polymerization (PIPOxA). Quantitative reaction with methyl triflate yields a macroinitiator salt (PIPOxOTfR/A) for the preparation of molecular brushes via the grafting from approach by living cationic polymerization of 2-oxazolines (2-methyl-, 2-ethyl-, and 2-isopropyl-2-oxazoline). Characterization of the resulting molecular brushes by NMR and FTIR spectroscopy indicates a very high side chain grafting density and quantitative reactions. Visualization of adsorbed molecular brushes by AFM corroborates this assumption. Furthermore, the lower critical solution temperatures of the POx molecular brushes were determined. The transition temperatures were found to be very defined, reversible, and with no noticeable hysteresis.

http://pubs.acs.org/doi/abs/10.1021/ma802627y