2-Isopropenyl-2-oxazoline: A versatile monomer for functionalization of polymers obtained via RAFT

Christine Weber, Toni Neuwirth, Kristian Kempe, Bengi Ozkahraman, Emel Tamahkar, Humeyra Mert, C Remzi Becer, Ulrich S. Schubert

Research output: Contribution to journalArticleResearchpeer-review

44 Citations (Scopus)

Abstract

2-Isopropenyl-2-oxazoline (iPOx) was polymerized for the first time via a controlled radical polymerization technique. Reversible addition-fragmentation chain transfer (RAFT) polymerization utilizing a dithiobenzoate-based chain transfer agent was employed to form a backbone that is highly reactive toward thiols and acids. Moreover, the statistical copolymerization of iPOx with methyl methacrylate (MMA) and N-iso-propylacrylamide (NiPAm) was investigated resulting in two copolymer series with iPOx content varying from 100% to 13% (PDI = 1.37 to 1.21). The P(iPOx-stat-NiPAm) copolymers displayed thermoresponsive behavior in water as well as phosphate buffered saline at higher temperatures in comparison to homopolymers of NiPAm due to the hydrophilicity of the introduced iPOx moieties (T cp = 25 to 75 °C). Futhermore, iPOx-based (co)polymers were functionalized by polymer analogous addition reactions with thiophenol, benzoic acid and 4-azidobenzoic acid in high conversions (74-100%). The latter adduct represented a suitable building block for the synthesis of a graft copolymer consisting of a PMMA backbone and poly(2-ethyl-2-oxazoline) (PEtOx) side chains via copper-catalyzed azide-alkyne cycloaddition (CuAAC) of PEtOx with alkyne terminus.

Original languageEnglish
Pages (from-to)20-27
Number of pages8
JournalMacromolecules
Volume45
Issue number1
DOIs
Publication statusPublished - 10 Jan 2012
Externally publishedYes

Cite this