An inverse gas-chromatographic study of the interaction of water with some cellulose derivatives

The sorption isotherms for water on cellulose triacetate, cellulose acetate (degree of substitution 2.45), cellulose monoacetate (degree of substitution 0.89), and ethyl cellulose were measured by finite‐concentration inverse gas chromatography. The isotherms for cellulose monoacetate were also measured with a vacuum microbalance. Polymer–solvent interaction parameters and partial molar heats of sorption at zero concentration of water were estimated from the extrapolated data, but kinetic effects and isotherm curvature lowered the precision of these results. The water sorption isotherms were examined according to the Zimm cluster theory, and the results were compared to those for cellulose and (hydroxypropyl)cellulose.