Eco-friendly carboxymethyl cellulose nanofiber hydrogels prepared via freeze crosslinking and their applications
—Development of highly versatile hydrogel materials using biomass materials—

As a solution to the environmental problem stemming from plastic residues in the environment, biodegradable materials that are biodegraded by microorganisms existing in the natural world are attracting increasing attention. However, conventional biodegradable materials have problems in terms of strength and moldability.

This research has revealed that a high strength hydrogel can be prepared by adding an aqueous solution of citric acid to a frozen carboxymethyl cellulose nanofiber (CMCF) and then thawing the sol. The reaction between the freeze-concentrated CMCF and CA created a rigid porous structure, which resembled the ice crystal structure.

The cellulose hydrogel material obtained through this technique exhibited sufficient strength that withstands a compression load of 2 tons along with a high level of moldability that allows it to be molded into different three-dimensional shapes. In addition, the material has the potential to be used as an adsorbent to remove hazardous substances.

The results are expected to be applied to a wide applications as new plastic substitutes that do not remain in the environment, environmental clean-up materials, and even regenerative medicine materials.