3D structure of lightweight, conductive cellulose nanofiber foam

We investigate the three-dimensional (3D) structuring of cellulose nanofiber (CNF) foam-based ink using direct ink writing 3D printing and the transformation of CNF foam from an insulator to a conductor. The colloidal stability of a CNF foam is critical to producing a solid CNF foam which can be used as a template for the synthesis of conducting polymers. Liquid CNF foam ink is produced by simple stirring of CNF suspension with sodium dodecyl sulfate as an emulsifier. The shear thinning behavior of the liquid CNF foam ink enables printing through a needle. Flexible design of CNF foam structures is enabled by 3D printing using computer-aided design. Lightweight conductive CNF foams are prepared via in situ polymerization of polypyrrole on a solid CNF foam. The topological features of the resultant porous conductive CNF foams are observed, and their conductivity is investigated.

Automated summary

This study examines the 3D structuring of cellulose nanofiber foam-based ink and the transition of foam from insulator to conductor. The colloidal stability of the foam is crucial for producing a solid template for the synthesis of conducting polymers. Liquid foam ink is prepared by stirring a CNF suspension with an emulsifier, allowing for shear-thinning behavior and flexible design of structures through 3D printing. Conductive CNF foams are prepared via in situ polymerization on solid foam, with observed topological features and conductivity investigation.