Poly(2-oxazoline) molecular brushes by grafting through of poly(2-oxazoline)methacrylates with aqueous ATRP

• Main Authors: Jordan, Rainer, Gieseler, Dan
• Other Authors: Royal Society of Chemistry,
• Format: Article
• Language: English
• Published: Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden 2015
• Subjects: Makromolekulare Chemie; Macromolecular Chemistry; ddc:540; ddc:530; rvk:VA 1120; rvk:UA 1000
• Online Access: http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-188802; http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-188802; http://www.qucosa.de/fileadmin/data/qucosa/documents/18880/c5py00561b.pdf

Molecular brushes of poly(2-oxazoline)s (POx) are an intriguing class of polymers as they combine a unique architecture with the properties of POx as a biomaterial. Here, the synthesis of several POx macromonomers with methacrylate end groups and consecutive grafting through polymerization by aqueous atom transfer radical polymerization (ATRP) at room temperature is reported. 1H-NMR spectroscopy and size exclusion chromatography (SEC) confirmed the synthesis of POx molecular brushes with maximum side chain grafting densities, narrow molar mass distributions (Đ ≤ 1.16) and final molar masses corresponding to the initial macromonomer : initiator ratio. Chain extension experiments show high end group fidelity and formation of block copolymer molecular brushes, and kinetic studies revealed a polymerization behavior of oligo(2-methyl-2-oxazoline) methacrylate very similar to the frequently used oligo(ethylene glycol) methacrylate (OEGMA475). Aqueous solutions of POx molecular brushes with poly(2-ethyl- and 2-isopropyl-2-oxazoline) side chains exhibit the typically defined thermoresponsive behavior with a tunable, very narrow and reversible phase transition