The Nature of the Supramolecular Structural Variation and Hydrophilic Properties of Cellulose during Water Sorption

Resumo

Water sorption on cellulose was studied in detail. The mechanism of the adsorption–desoprtion hysteresis loop was considered using NMR relaxation methods and sorption phenomena. The degree of crystallinity was found to decrease in cellulose during water sorption, while the specific surface area of cellulose increased because a wedging pressure arose as a new adsorbent–adsorbate interface formed. The most significant changes in these parameters were observed during desorption and were accompanied by the formation of an additional capillary-porous system in cellulose. Correlations were observed between the surface tension coefficient at the solid–liquid interface, the adsorption equilibrium constant, and the net heat of adsorption.