Vanillin: Key-Building Block from Lignin to Synthesis of Biobased Polymers

The synthesis of aromatic polymers from renewable resources is a real challenge. Vanillin is currently one of the only biobased aromatic compounds industrially available. Most vanillin is produced from petroleum, but part of the supply comes from lignin. At present, vanillin is used almost exclusively in the flavor and fragrance industry for food, body care and household applications.

The industrial processes used all generate large quantities of effluent, but there are many avenues for improvement, in particular to produce less pure vanillin, not intended for the food industry. Vanillin has already proved its worth in many materials as a replacement for petroleum-based substances. Vanillin is a non-hazardous compound with an aromatic ring, a structure sought after in many materials for its thermomechanical properties. The possibility of obtaining vanillin from renewable resources (lignin) is of considerable interest, as access to biosourced aromatic molecules is a real industrial challenge. Vanillin is thus a promising aromatic substance, industrially available and of undeniable interest for numerous applications. The current challenge is to improve extraction processes in order to reduce costs and impacts, leading to the development of vanillin as a biosourced aromatic platform molecule.

The aim of this article is to present current biobased vanillin production processes and the environmental impacts they generate; to review current work on the use of biobased vanillin in polymers; and to show the future challenges of this molecule of interest by putting into perspective the expected developments in production processes. This overview highlights vanillin's potential as a chemical reagent of renewable origin, particularly in the field of polymers such as polyepoxides, polyurethanes and phenolics, for applications in binders, coatings and composites.