4: Dynamic Vapour Sorption

Dynamic vapour sorption (DVS) is a gravimetric technique used to measure the weight loss/gain of a material as a function of humidity. It is possible to use organic solvents on many commercially available instruments. The most common experiment carried out using DVS analysers is the construction of sorption isotherms for materials. The raw data are usually presented as normalised weight percentage versus time. Sorption isotherms are conventionally presented as equilibrium water content versus relative humidity. This chapter considers the principles of the technique and discusses its application to a wide range of samples, including food, pharmaceuticals, textiles, building materials and explosives.