The surface properties of cellulose and lignocellulosic materials assessed by inverse gas chromatography: a review

The physicochemical surface properties of cellulose and lignocellulosic materials are of major importance in the context of the production of composites, in papermaking, and textile area. These properties can be evaluated by using inverse gas chromatography (IGC), a particularly suitable technique for the characterization of the surface properties of fibrous materials and powders. At infinite dilution conditions of appropriate gas probes, IGC may provide important parameters including the dispersive component of the surface energy of the material under analysis, thermodynamic data on the adsorption of specific probes, and Lewis acid-base interaction parameters between the matrix and the filler of composite materials. This paper critically reviews the most relevant results available in the literature concerning the characterization of cellulose and lignocellulosic materials using IGC. Emphasis will be put into the cellulose and nanocellulose surface properties, changes in the surface properties of cellulose and lignocellulosic materials after chemical and physical modifications, and in the compatibility of cellulose-based materials with polymeric matrices. The surface properties of non-woody fibers will also be considered. Before discussing the results available in the literature, the theoretical background and the main approaches used for the calculation of parameters accessed by IGC will be given. It is expected that this review can contribute to a better knowledge of the physicochemical surface properties of cellulosics.