Sustainable aerogels derived from bio-based 2,5-diformylfuran and depolymerization products of lignin

ABSTRACT

2,5-diformylfuran (DFF) is a promising green platform chemical obtainable by selective oxidation of 5-(hydroxymethyl)furfural (HMF). In this work, high-purity DFF was synthesized from HMF and compared to formaldehyde (F) in terms of suitability for polymerization in aqueous solution with various phenolic model substances that may be obtainable by depolymerization of lignin. Resorcinol, catechol, and phloroglucinol formed stable hydrogels with DFF, which were converted to alcogels and subsequently dried by extraction with supercritical carbon dioxide. Thermogravimetric analysis and scanning electron microscopy of the resulting aerogels showed no significant differences between DFF and F gels. The high porosity of the aerogels was confirmed by liquid nitrogen BET surface measurement; the specific surface areas measured varied significantly, ranging from 20 to 700 m² g⁻¹.

Graphical Abstract

KEYWORDS:

• 2, 5-diformylfuran
• lignin-depolymerization products
• sol-gel polymerization
• aerogels

Acknowledgments

The authors would like to thank M.Sc.Gottfried Aufischer from Wood Kplus for his valuable input into this work and guidance for testing.

Disclosure statement

No potential conflict of interest was reported by the authors. The funding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to publish the results.

Data availability statement

Data availability statement Data will be made available upon request to the corresponding author at [email protected]; www.wood-kplus.at.

Additional information

Funding

This work was carried out within the research project BioRest (Biopolymers from biogenic raw- and waste materials). The project was funded by the European Regional Development Fund (EFRE) and the province of Upper Austria.

Notes on contributors

Christoph Derflinger

Christoph Derflinger is a PhD student at the Institute for Chemical Technology of Organic Materials at the Johannes Kepler University Linz working for Wood K plus – Competence Center for Wood Composites & Wood Chemistry. He carried out the preparative work on the synthesis of the bio-based aerogels and is currently working on the development of heterogeneously catalyzed production methods for furandicarbaldehyde.

Birgit Kamm

Birgit Kamm is a Key researcher at Wood Kplus, Austría and an Honorary Professor Biorefinery Technology and Biobased Products at Brandenburg University of Technology, BTU Cottbus-Senftenberg. Her research is focused on commercially viable biobased platform chemicals and materials. She is currently working on understanding the structure–property relationships between renewably sourced biobased polymers, biobased polymer additives.

Christian Paulik

Christian Paulik is a Professor at the Johannes Kepler University Linz and Head of the Institute for Chemical Technology of Organic Materials with expertise in conventional and biobased plastics and biotechnololgy.