Dynamic Vapour Sorption
Dynamic Vapor Sorption (DVS) is a gravimetric technique that measures how quickly and how much of a solvent is absorbed by a sample.
It does this by varying the vapor concentration surrounding the sample and measuring the change in mass loss or uptake. Water vapor is most commonly used, but it is also possible to use a wide range of organic solvents.
The DVS instrument rapidly measures uptake and loss of moisture or organic vapours by flowing a carrier gas at a specified relative humidity over a sample (which can weigh between 1 mg and 4 g) suspended from the weighing mechanism of an ultra-sensitive recording microbalance. This particular microbalance is used as it is capable of measuring changes in sample mass lower than 0.1ppm , providing unrivalled long-term stability required for accurate measurements of vapour sorption, which may take from minutes to days to complete depending upon the sample size and material. A big factor of sorption behaviour is the need to establish rapid sorption. So the DVS instrument allows sorption behaviour to be accurately determined on very small sample sizes (typically 10 mg) to have a fast expiriment.