Poly-α,β-unsaturated aldehydes derived from castor oil via ADMET polymerization
✍ Scribed by Oliver Kreye; Tommy Tóth; Michael A. R. Meier
- Publisher
- John Wiley and Sons
- Year
- 2011
- Tongue
- English
- Weight
- 174 KB
- Volume
- 113
- Category
- Article
- ISSN
- 1438-7697
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✦ Synopsis
Abstract
10‐Undecenal, derived by pyrolysis and reduction from castor oil, was almost quantitatively transformed into the corresponding aldol condensation product under basic conditions. This α,ω‐diene monomer was polymerized using acyclic diene metathesis (ADMET) polymerization. In a catalyst screening, four of nine different ruthenium‐based metathesis catalysts showed good reactivity under neat conditions at 80°C in the presence of 1,4‐benzoquinone and polymers with molecular weights up to 11 kDa were formed. Furthermore, the ^1^H NMR spectra showed that the metathesis catalysts tolerate the α,β‐unsaturated aldehyde function and due to the addition of benzoquinone, the degree of double bond isomerization was low. Further experiments investigating reduced catalyst amounts (down to 0.2 mol%) and the temperature dependence of these ADMET polymerizations gave also satisfying results for the formation of poly‐α,β‐unsaturated aldehydes. Moreover, ADMET polymerizations with different amounts of methyl 10‐undecenoate as chain‐stopper were performed and the integrals of the corresponding ^1^H NMR spectra allowed the determination of an absolute degree of polymerization. Finally, a reduction of a poly‐α,β‐unsaturated aldehyde with sodium borohydride was accomplished. The resulting poly‐(allyl alcohol) could be a useful compound in the generation of polymer networks like polyesters, polyurethanes, and polycarbonates and thus be of high interest in materials research.