Highly swellable hydrogels prepared from extensively oxidized lignin
JiHyeon Hwang,
Daniella V. Martinez,
Estevan J. Martinez,
Gift Metavarayuth,
Dustin Goodlett,
Qi Wang,
Mitra Ganewatta,
Michael S. Kent,
Chuanbing Tang
Affiliations
JiHyeon Hwang
Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208, USA
Daniella V. Martinez
Joint BioEnergy Institute, Emeryville, CA 94608, USA; Sandia National Laboratories, Albuquerque, New Mexico, 87185, USA
Estevan J. Martinez
Joint BioEnergy Institute, Emeryville, CA 94608, USA; Sandia National Laboratories, Albuquerque, New Mexico, 87185, USA
Gift Metavarayuth
Ingevity Corporation, 5525 Virginia Avenue, North Charleston, SC 29406, USA
Dustin Goodlett
Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208, USA
Qi Wang
Ingevity Corporation, 5525 Virginia Avenue, North Charleston, SC 29406, USA
Mitra Ganewatta
Ingevity Corporation, 5525 Virginia Avenue, North Charleston, SC 29406, USA; Corresponding authors.
Michael S. Kent
Joint BioEnergy Institute, Emeryville, CA 94608, USA; Sandia National Laboratories, Albuquerque, New Mexico, 87185, USA; Corresponding author at: Joint BioEnergy Institute, Emeryville, CA 94608, USA.
Chuanbing Tang
Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208, USA; Corresponding authors.
Biopolymers such as lignin are gaining renewed appeal due to the need for sustainable materials. Herein, we used chelator-mediated Fenton (CMF) chemistry to oxidize Kraft lignin to develop sustainable super absorbent materials. The CMF chemistry adds oxygen, opens aromatic rings and increases COOH content, producing hydrophilic lignin without depolymerization. UV absorption, molecular weight, elemental analysis, and titration were used to study the chemical compositions of CMF-processed lignin. Then the chemically modified hydrophilic lignin was used to produce lignin-based hydrogels utilizing an aqueous polymerization and cross-linking reaction that enabled tunable properties. The resulting lignin hydrogels absorbed water up to 96% and swelled up to 2400%, as well as being re-swellable in water. These lignin-based hydrogels may be applicable in water-absorbing products in consumer goods and agriculture.
