Preparation of Methacrylate End-Functionalized Poly(2-ethyl-2-oxazoline) Macromonomers
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Weber, Christine; Becer, C. Remzi; Baumgärtel, Anja; Hoogenboom, Richard; Schubert, Ulrich S.
- Abstract:
- Three methods for the functionalization of 2-ethyl-2-oxazoline (EtOx) oligomers with a methacrylate or
methacrylamide unit are compared to identify the best suitable route to obtain such macromolecules. In the
first method, a functional initiator, namely methacryloyl chloride, was used for the cationic ring-opening
polymerization of EtOx, which proceeded in a living manner. However, the formation of a large amount
of hydrogen initiated chains resulted in a low degree of functionalization (21%). The second method was
based on the termination of active oligo(EtOx) chains with an aqueous sodium carbonate solution yielding
hydroxyl-terminated oligomers. These end-groups were subsequently modified by an esterification reaction
with methacryloyl chloride yielding oligomers with a large variety of different end-groups, as demonstrated
by MALDI-TOF-MS. In the last method, the living chain ends were reacted with in situ formed triethyl ammonium
methacrylate yielding macromonomers with a high degree of functionalization (>80%). Besides,
MALDI-TOF-MS analysis revealed only a single oligomer distribution with the desired end-groups. Furthermore,
these directly end-capped oligomers revealed narrow molar mass distributions with PDI values
below 1.2 making this the best method for macromomonomer synthesis.
- Year:
- 2009
- Type of Publication:
- Article
- Keywords:
- Poly 2-ethyl-2-oxazoline; MALDI-TOF-MS; end-functionalization; living polymerization; macromonomer
- Journal:
- Designed Monomers and Polymers
- Volume:
- 12
- Pages:
- 149 - 165