Modification of Water Sorption Capacity of Polydimethylsiloxane based Composites by Incorporation of Lignin

Lignin, a natural renewable material, was incorporated in a series of polydimethylsiloxane/silica composites. Besides the effect as bulk filler, the presence of lignin determines the change of some properties among them being surface properties that were evaluated by contact angle and water sorption measurements. The contact angles were determined in static regime by using the sessile drop technique. Dynamic water vapour sorption was applied to register the sorption/desorption isotherms and kinetic curves. The sorption type and maximum vapour sorption capacity were evaluated based on these data. The results were correlated with the composition of the prepared materials.