Correlating the thermomechanical properties of a novel bio-based epoxy vitrimer with its crosslink density

摘要: Vitrimers have covalent crosslink structures as normal thermoset polymers, but they possess unique properties of being able to go through plastic deformation due to their crosslinks being dynamically exchangeable above a particular temperature. This new type of polymers is getting increased attention owing to their reprocessing, remolding, and recycling properties, along with the thermoset characteristics. As a thermoset, the materials’ degree of crosslinking, namely crosslink density, is essential to their physical and mechanical properties. Herein, a series of dynamic epoxy crosslinking networks with different crosslink densities were prepared by changing the ratio of two epoxies N,N-diglycidyl-4-glycidyloxyaniline, and butanediol diglycidyl ether but keeping the same stoichiometric ratios when cured with a hardener synthesized from bio-based lignin-derived vanillin. The reaction enthalpy (ΔH) and glass transition …