New Model of Wood Cell Wall Microfibril and Its Implications

Abstract

Traditionally it has been accepted that the cell walls are made up of microfibrils which are partly crystalline. However, based on the recently obtained Raman evidence that showed that the interior of the microfibril was significantly disordered and water accessible, a new model is proposed. In this model, the molecular chains of cellulose are still organized along the fibril direction but, at the local level, the chains retain significant degrees of freedom. The new fibril model has implications for not only formation of inter-chain H-bonds and therefore, cellulose ultrastructure but also, a number of areas of practical applications where cellulose fibers are used. Various research and development areas, including biofuels and nanocellulose fields, are likely to be impacted. Based on the new model, the broadened nature of X-ray diffractograms of cellulose I materials and lack of crystallinity increase upon pulp and cellulose nanocrystals (CNCs) production were interpreted in terms of degree of consolidation of cellulose chains within the microfibrils rather than their crystallite size.

Citation

Agarwal, Umesh P.; Ralph, Sally A.; Reiner, Rick S.; Baez, Carlos. 2015. New Model of Wood Cell Wall Microfibril and Its Implications. Proceedings of the 18th ISWFPC (International Symposium on Wood, Fiber, and Pulping Chemistry) held in Vienna (Sept 9 -11, 2015). pp. 142-145.