Plant Oil and Lignin-Derived Elastomers via Thermal Azide–Alkyne Cycloaddition Click Chemistry

The developments of sustainable elastomers from natural biomass to compete fossil fuel-derived elastomers are gaining increasing attention during recent years. In this work, elastomer derived from soybean oil and lignin was developed via a metal-free thermal azide–alkyne cycloaddition reaction (TAAC). Azide-containing polymers derived from soybean oil and alkyne-functionalized lignin were first prepared and confirmed via FT-IR, NMR, and GPC. A mixture of azide-containing polymers/lignin-alkyne was then thermal cured via TAAC, which afforded thermoset elastomers. The mechanical properties as well as elasticity were calculated via tensile tests. Moreover, mechanical properties of these elastomers could be facilely tuned via controlling the azide content in the soy-based polymers and the ratio of lignin-alkyne cross-linkers.