Manometric-gravimetric-oscillometric measurements

Figure 5.16. Scheme of an instrument for manometric-gravimetric-oscillometric measurements of binary coadsorption equilibria in swelling materials (polymers, resins etc.) without sorptive gas analysis by GC or MS. 

Combining the dielectric measurements with either manometric, gravimetric or oscillometric measurements of gas adsorption equilibria states, one gets calibration curves allowing one the determination of Gibbs excess adsorbed masses by purely electric measurements which normally can be performed fairly quickly and on site in industrial situations. 

We also would like to draw reader s attention to the possibility to combine oscillometric, gravimetric, and manometric measurements in a single experiment. The schematic diagram of such an instrument is given in Figure 5.16. It basically consists of a rotational pendulum, a microbalance (two beams as indicated in Fig. 5.16 or single beam as sketched in Fig. 5.15) and a storage vessel for the sorptive gas. This instrument would allow cosorption... 

For swelling sorbents like polymers and resins, combined osciUometric-gravimetric or oscillometric-manometric measurements allow one to determine simultaneously the total mass (m + m ) and the volume (V ) of the sorbent / sorbate system. In this way, for example, a shift in the glass transition temperature of a polymer due to gas absorption can be observed. 

For rigid sorbent materials, combined oscillometric-gravimetric or oscillometric-manometric measurements in a saturation state of an adsorption system also allow one to determine both the total mass (m m ) and the Volume (V ) of the system without using the so-called helium volume hypothesis, cp. Fig. 5.8 and Chap. 1. 

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