Poly‐α,β‐unsaturated aldehydes derived from castor oil via ADMET polymerization

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 a,v-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 808C 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 a,bunsaturated 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-a,b-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-a,b-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.

Renewable rosin fatty acid polyesters: the effect of backbone structure on thermal properties

“…Acyclic diene metathesis (ADMET) polymerization was used to prepare polymers. 21,22,24,25 Both Grubbs second generation and Hoveyda-Grubbs second generation catalysts were used; however, the Hoveyda-Grubbs catalyst provided better results, including fast reactions and higher molecular weight. As shown in Figure 4, 1 H-NMR spectrum of the fi nal polymer displayed a loss of the terminal alkene peak at 4·9 ppm, which was expected for an ADMET polymerization.…”

“…Among natural molecular biomass, fatty acids have shown to be a prime resource for polymer chemistry. [21][22][23][24][25] Derived from castor oil, 10-undecenoic acid is one of the most important fatty acids with a fl exible, linear structure and can undergo a number of synthetic reactions to produce renewable monomers for polymer synthesis. 24,26,27 In contrast, rosin that is obtained from pine resin is available with a more rigid fused-ring structure, and can also undergo a pyramid of reactions.…”

“…[21][22][23][24][25] Derived from castor oil, 10-undecenoic acid is one of the most important fatty acids with a fl exible, linear structure and can undergo a number of synthetic reactions to produce renewable monomers for polymer synthesis. 24,26,27 In contrast, rosin that is obtained from pine resin is available with a more rigid fused-ring structure, and can also undergo a pyramid of reactions. 20,[28][29][30][31][32][33][34][35][36] Olefi n metathesis and thiolene reactions are just a few examples of highly effi cient reactions that take advantage of the unsaturated terminal olefi ns to produce valuable monomers.…”

Metathesis Curing of Allylated Lignin and Different Plant Oils for the Preparation of Thermosetting Polymer Films with Tunable Mechanical Properties

“…In our group, star‐ and block copolymers from 10‐undecenyl acrylate via ADMET polymerization were intensively studied . In addition, various linear polymers starting from 10‐undecenoic acid, 10‐undecenal, methyl oleate, or methyl erucate were prepared via ADMET …”

“…[19][20][21] In addition, various linear polymers starting from 10-undecenoic acid, 10-undecenal, methyl oleate, or methyl erucate were prepared via ADMET. [22][23][24] Likewise, the application of plant oils in renewable thermosets is described via various methods. Besides copolymerization to produce epoxy thermosets [25,26] or polyurethanes, [27] and radical homopolymerization, [28] metathesis is an equally powerful but up to date less investigated tool for the synthesis of renewable thermosets from plant oils.…”