Fabrication of a model cellulose surface from straw with an aqueous sodium hydroxide/thiourea solution

摘要

Model cellulose surfaces were prepared with both microcrystalline cellulose and cellulose isolated from wheat straw with different molecular weights. A sodium hydroxide/thiourea aqueous solution, instead of any organic solvents, worked as the solvent for dissolving cellulose, and model cellulose films were prepared by a two-step method: first, the cellulose solution was deposited onto the surface of the substrate with the spin-coating method, and second, the as-prepared film was washed with deionized water to remove the impurities and was formed with a flattened surface. Atomic force microscopy was used to measure the morphology, surface roughness, and thickness of the cellulose thin films. X-ray photoelectron spectroscopy and energy-dispersive X-ray spectrometry were used to characterize the surface chemical information of the films. The results revealed that model cellulose surfaces could form from both kinds of cellulose. (C) 2008 Wiley Periodicals, Inc.