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Abstract Reprocessable and biobased thermosets are prepared from two renewable feedstocks, lignin and polyamine (Priamine 1071). Lignin is oxidized to produce polycarbonyl and further reacts with polyamine to form a crosslinked network of imines. The thermoset materials are formed under heat and pressure in the absence of any catalysts. The mechanical strength and thermal properties of thermosets are tunable by changing feedstock ratios. The dynamic imine crosslinks can be associatively reformed. 

Lignin is a renewable feedstock that is abundant and inexpensive but still presents challenges for its valorization. In this work, we converted functionalized lignin into broad-spectrum adhesives using thiol–silyl ether crosslinkers. The curing behavior of adhesives was investigated via rheology of their resin forms. These materials exhibit good adhesion on diverse substrates, including wood, glass, steel, aluminium, carbon fiber, and different plastics, with the most adhesion strength in the range of 1–3 MPa. These adhesives were also explored for applications, ranging from wet conditions to different mechanically responsive materials. The mechanism of adhesion was further examined to understand the bonding process. 

Biomass-based polymers show promise for the mitigation of environmental issues associated with petroleum-derived commodity polymers; however, due to poor entanglement, many of these polymers typically lack mechanical strength and toughness. Herein, we report a facile approach to utilizing metal–ligand coordination to create physical crosslinking, and thus chain entanglements for plant oil-derived polymers. A series of soybean oil-derived copolymers containing a pendant acid group can be easily synthesized using free radical polymerization. The resulting chain architecture can be controlled through supramolecular interactions to produce bioplastics with enhanced thermomechanical properties. The metal–ligand coordination in this work can be varied by changing the metal lability and the density of metal–ligand bonds, allowing for further control of properties. The final bioplastics remain reprocessable and feature good thermoplastic and stimuli-responsive properties.