Sustainable lignin-based thermoplastic elastomer derived from furfural and terpenes, with good mechanical properties, adhesion properties, and UV absorption properties.

To enhance the application potential of lignin, lignin-based thermoplastic elastomers were developed by utilizing sustainable monomers. This work used grafting strategy to introduce terpene-derived monomer tetrahydrogeraniol acrylate (THGA) and tetrahydrofurfuryl methacrylate (TFMA) derived from furfural into lignin to obtain sustainable lignin-based thermoplastic elastomers. The findings indicate that the long-branched structure of THGA enables the lignin-based elastomer to achieve a reduced Tg. By modifying the ratio of the two biomass monomers, the Tg and mechanical properties can be regulated. Lignin plays an indispensable role in enhancing mechanical action. With identical monomer molar ratio input, lignin graft copolymers exhibit superior mechanical properties compared to linear copolymers. For instance, the fracture stress of Lignin0.50-PTFMA700 is 6.3 MPa, the fracture elongation is 277 %, the fracture stress is 2.5 times higher than PTFMA700, moreover, Lignin0.59-PTFMA500 also has good elastic recovery ability. Meanwhile, Lignin0.59-PTFMA500 exhibits excellent adhesion to various substrates, with a shear strength of 2.0 MPa on glass substrates. Additionally, these lignin-based thermoplastic elastomers also possess outstanding ultraviolet absorption performance. This offers a novel research idea for developing sustainable functional monomers and broadening the high-value addition of lignin.