Biobased polymers

In an era where the discussion about environmental pollution is at the forefront, modern societies still rely on oil to meet their daily needs. Clothing, transportation, packaging, housing are some of the sectors that shape the image of everyday life and they all exploit oil as their primary feedstock. However, fossil fuels are a finite raw material and their use entails further aggravation of the environmental problem we are facing.

Research is focusing on the exploitation of renewable feedstocks to provide chemicals and materials for a sustainable, circular economy that is not dependent on fossil fuels. Two major strategies that have been successfully exploited are biorefining, isolating abundant biochemicals (e.g., sugars, oils, fats, and amino acids) or biopolymers (e.g., lignin, cellulose, starch, chitin) from natural sources, and bioengineering, using genetically modified microbes to produce natural and non-natural metabolites. In the bioengineering category, lactic acid, propanediol, itaconic acid and succinic acid stand out.

Our team focuses on the synthesis of polymeric materials derived from such renewable feedstocks, inspired to contribute to an eco-friendly society whose daily life includes only biobased commodity plastics. Our main interests include:

2,5-furan dicarboxylic acid (2,5 FDCA): FDCA is the biobased equivalent of terephthalic acid (TPA), that is used for the production of poly(ethylene terephthalate) (PET), the most abundant commercial polyester today. Its precursor, hydroxymethylfurfural (HMF) is a product of dehydration of sugars. Polyesters derived from FDCA are considered to be ideal replacements for their terephthalic counterparts since they possess improved features like higher glass transition and lower melting temperature, along with significantly improved gas barrier properties. Our team is investigating polymerization conditions and catalysts for a variety of FDCA derived polyesters, copolyesters and nanocomposites and how important parameters like thermal transitions, thermal degradation, biodegrability and mechanical properties are influenced. You can find our pubications on FDCA-based polyesters here.

Itaconic acid (IA): IA is a biobased monomer produced on industrial scale (>80.000 t/a) via fermentation of sugars with the fungi aspergillus terreus. An interesting feature of IA is its versatility. Since it possesses two carboxylic groups and an exo-double bond, it is a good substrate for different chemical transformations. This versatility also applies for the production of polymers. Two main strategies emerge: first, the utilization of the unsaturated double bonds for radical polymerization of homo-polymers and co-polymers and second, the synthesis of unsaturated polyesters. Main interest focus of our group is the production of unsaturated polyester resins designed for thermal or UV curing applications, like adhesives or 3D printing materials.

Vanillic acid (VA): VA is the oxidation product of vanillin, a well-known food flavoring agent, derived from lignin. Lignin is one of the most abundant organic polymers on Earth, exceeded only by cellulose, and therefore an ideal feedstock to utilize for the production of chemicals and polymers. VA’s aromatic structure makes it a candidate for potential replacement of TPA, in the production of biobased materials for packaging applications. Our group works on the development of polymers derived from vanillic acid, mainly polyesters and copolyesters, examining catalytic systems and polymerization conditions along with the thermal and mechanical properties of the resulting materials.

Further reading: Review articles from BikiarisLab