Design of New Amphiphilic Triblock Copoly(2-oxazoline)s Containing a Fluorinated Segment

Kempe, Kristian; Baumgärtel, Anja; Hoogenboom, Richard; Schubert, Ulrich S.
Abstract:
New amphiphilic triblock copoly(2-oxazoline)s, containing hydrophobic domains with fluorine-containing blocks, were synthesized. Using microwave radiation as heating source, triblock copolymers with narrow molar mass distributions were obtained by the sequential addition of 2-ethyl-2-oxazoline, 2-(1- ethylheptyl)-2-oxazoline, and 2-(2,6-difluorophenyl)-2-oxazoline. The polymers obtained were characterized by size exclusion chromatography, 1H NMR spectroscopy and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). To investigate the incorporation of all three monomers into the triblock copolymers, a model polymer was prepared with shorter blocks exhibiting a suitable length to be measured in the reflector mode of a MALDI-TOF MS. In addition, kinetic investigations on the homopolymerizations of all monomers were performed in nitromethane at 140 C, yielding the polymerization rates under these conditions. DSC measurements of poly(2-(1-ethylheptyl)-2-oxazoline) and poly(2-(2,6-difluorophenyl)- 2-oxazoline)) revealing glass transitions at about 33 and 120 C, respectively. The thermal analysis of a blend of the two polymers showed two glass transitions revealing demixing, which could be an indicating for the immiscibility of the two components in the block copolymers.
Year:
2010
Type of Publication:
Article
Journal:
Journal of Polymer Science: Part A: Polymer Chemistry
Volume:
48
Pages:
5100 - 5108