As the most abundant natural aromatic polymer on earth, lignin is expected to replace fossil resources to prepare high-performance thermosetting polymers. Numerous studies have been devoted to the utilization of lignin through depolymerization and chemical modification, nevertheless, green and facile valorization of lignin to high value products is still a challenge. Herein, we developed a straightforward approach to directly use lignin to prepare thermosetting polymers combining high performance and excellent degradability. In a green acetone-water-acetic acid component solvent system, lignin-based thermosets were facilely prepared via cross-linking reactions between lignin and silane coupling agent KH560. The thermosets exhibited outstanding thermal and mechanical properties with glass transition temperature of ~214 °C, tensile strength of ~45 MPa and Young''s modulus of ~2274 MPa, and these properties can be easily manipulated by adjusting the ratio of lignin and KH560. In addition, the thermosets possessed the ability of 100% UV shielding. The presence of Si-O-C bonds and ester bonds in the network structure imparts excellent degradability to the thermosets in alkaline aqueous solution. This work provides a green and facile strategy to directly integrate lignin into cross-linked networks, which discloses a new idea for the valorization of lignin to value-added materials.

论文链接：https://pubs.rsc.org/en/content/articlelanding/2022/gc/d2gc03302j