Unexpected Reactivity for the RAFT Copolymerization of Oligo(ethylene glycol) Methacrylates
-
Pietsch, Christian; Fijten, Martin W. M.; Lambermont-Thijs, Hanneke M. L.; Hoogenboom, Richard; Schubert, Ulrich S.
- Abstract:
- Homo- and copolymers of di(ethylene glycol) methyl ether methacrylate
(DEGMA) and oligo(ethyleneglycol) methyl ether methacrylate (OEGMA1100) were
synthesized with various chain lengths via reversible addition fragmentation chain
transfer (RAFT) polymerization in ethanol using [M]/[RAFT] ratios of 100 and 200.
Kinetic investigations on the homo- and copolymerization of these monomers were
performed using a parallel synthesizer resulting in well-defined polymers with polydispersity
indices mostly below 1.3. The polymerization kinetics are presented and
discussed in detail surprisingly revealing that the DEGMA homopolymerization is
slower than the OEGMA1100 homopolymerization. Transfer coefficients capp
tr were estimated
to be ~0.5 for the RAFT polymerization of both DEGMA and OEGMA1100
resulting in hybrid behavior at the beginning of the polymerizations. Subsequent
copolymerization also revealed fast incorporation of the OEGMA1100 and relatively
slow incorporation of DEGMA resulting in well-defined copolymers with a molecular
weight up to 100 kDa and polydispersities around 1.20.
- Year:
- 2009
- Type of Publication:
- Article
- Keywords:
- chain transfer coefficient; controlled radical polymerization; copolymerization; oligo ethyleneglycol methyl ether methacrylate; polymerization kinetics; reversible addition fragmentation chain transfer; RAFT
- Journal:
- Journal of Polymer Science: Part A: Polymer Chemistry
- Volume:
- 47
- Pages:
- 2811 - 2820