Wood-based hemicelluloses as renewable source for functional materials

Trees are a tremendous source of renewable materials comprising mainly cellulose, hemicellulose and lignin. Hemicelluloses are a complex component of wood cell wall that contribute to the strong network with cellulose fibrils. The structure of the hemicellulose grades depends on the plant species and extraction method. While cellulose is, and has been, of scientific and industrial interest, wood-based hemicelluloses, xylan being the principle type of them, have had very limited use in industrial applications. So far, the main attention of hemicelluloses has been as a raw material for biobased chemicals. In materials technology applications, investigations have been directed in modification of the wood-based hemicelluloses to tune their water-solubility, functionality, film formation, among others. In addition to solid structures such as films, hemicelluloses are suggested as interfacial stabilizers. In this contribution etherified and oxidized hemicellulose grades are suggested for applied materials science purposes. The surface activity and interfacial stabilization capability of hardwood and softwood hemicellulose ethers is contrasted to their structural features. Oxidized xylan grades are presented as a novel material for functional hemicellulose films.