Lignin is an abundant, renewable material that has the potential to yield valuable, low molecular weight, single aromatic chemicals when strategically depolymerized. In order to generate a highly bio-based thermoset for use in polymer composites, a lignin-derived chemical, vanillin, was methacrylated in a two-step, one-pot synthesis to produce a vinyl ester resin (87 cP at 25 °C) with a 1 : 1 mole ratio of a mono-functional monomer, methacrylated vanillin, to cross-linking agent, glycerol dimethacrylate. The synthetic scheme was solventless, required little catalyst and moderate reaction temperatures while generating no by-products. Upon resin curing, a hard, transparent thermoset with a broad glass transition, Tg = 155 °C (based on the tan δ maximum), and a temperature of maximum decomposition rate, Tmax, of 426 °C was produced. Overall, a potentially 100% bio-based thermoset was synthesized possessing comparable thermo-gravimetric and thermo-mechanical properties to commercial vinyl ester-based thermosets.
