itaconic

Itaconic acid, also known as 2-methylenebutanedioic acid, is an unsaturated dicarboxylic acid used as a renewable monomer in polymer chemistry. The molecule contains two carboxyl groups and a vinylidene substituent, which provides both acidic functionality and a carbon–carbon double bond suitable for various chemical reactions.

In nature and industry, itaconic acid is produced primarily by microbial fermentation. Strains of Aspergillus terreus are the most common producers, converting sugars and other carbohydrate feedstocks into itaconic acid. In the biosynthetic pathway, the enzyme aconitate decarboxylase converts cis-aconitate, an intermediate of the citric acid cycle, into itaconate, which is then secreted into the fermentation broth and recovered as the acid or as calcium itaconate before purification.

Industrial production relies on fermentation followed by purification and purification steps to obtain high-purity itaconic acid suitable for polymer applications. It also serves as a model bio-based monomer for developing sustainable alternatives to petrochemical-derived acrylates and other vinyl polymers.

Applications of itaconic acid include the production of polyitaconic and itaconate-containing polymers used in coatings, adhesives, sealants, and some hydrogels and superabsorbent materials. Its functionality enables crosslinking and incorporation into polymer networks, contributing to bio-based resin and coating technologies. Ongoing research seeks to improve fermentation efficiency, recovery processes, and the range of polymers that can be made from itaconic acid.