Unrefined wood hydrolysates are viable reactants for the reproducible synthesis of highly swellable hydrogels

• A robust sequential synthetic pathway for renewable hydrogel production is developed.
• Crude wood hydrolysate biomass, rich in hemicellulose and lignin, was used as a reactant.
• Swelling ratios as high as Qeq = 270 were achieved.

A value-adding robust and sequential synthetic pathway was elaborated to produce hydrogel structures with ionic character from crude acetylated galactoglucomannan-rich wood hydrolysate (WH). The WH was first-step liquor originating from a sulphite cracking pulp process for dissolving pulp. The synthetically modified WH fractions were verified at each step by NMR and FTIR, and the hydrogels were characterized with respect to their swelling and mechanical properties. Altering the crosslinking chemistry and the content of ionic moieties resulted in hydrogels with various swelling ratios and mechanical properties. Renewable hydrogel formulations with swelling ratios as high as Qeq = 270 were achieved.