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effect on the position of the isotherm. According to the X-ray structural analysis
of the crystallinity of PVA slightly decreases with increasing p/p5.
Analysis of the results carried out in the framework of a dual sorption
model, the theory of hydrate deposits, taking into account the degree of
crystallinity and osmotic pressure. First sorption studies in practice defined
osmotic pressure, caused by the presence of crystallites grids whose values are in
the glassy state varies from 40 to 100 MPa.
Proposed and implemented processing algorithm sorption isotherms to
obtain information on the thermodynamic parameters of the interaction between
glassy polymers with water. It is the consistent exclusion of the influence of the
crystal, the structure of non-equilibrium effects associated with the osmotic
pressure of the crystallites grid, glassy polymeric sorbent.
The reduced manner isotherm can be considered as much as possible close
to the equilibrium. Her treatment by the equations of the theory of Flory-
Huggins allowed to calculate the value of x> which was 0.35 ± 0.10, which is in
good agreement with the results obtained by other methods.
Amorphous silica samples - (8102) which is prepared from TMOS and
aerosil. It is shown that depending on the kinetic sorption of water vapor in both
cases vary in accordance with Fick's law.
The obtained sorption isotherm - desorption - a concave curve with a
characteristic hysteresis loop, and bend in the river/p5 ~ 0.6 for the (8 (From) for
aerosil hysteresis is observed at values of p/p3 near 1, for (8 Yug.) - In .. the
range p/p5 from 0.2 to 0.7 on the assessment of these sections of pore sizes was
conducted in accordance with the equation of the Kelvin and built their size
distribution. Thus, the average radius (8102) is n - 1.5-2 nm for aerosil - 10-20
nm.
Organic-inorganic sorbents. The kinetic curves of sorption for mixtures of
compounds under study do not differ from those described above. Typical water
sorption isotherms of organic-inorganic sorbents, where it can be seen that the
introduction of the amorphous silica of hydrophilic polymers results:
- In - first changing the nature of the sorption isotherms in the transition
from polymer to polymer-inorganic systems they become concave, and then -
convex;
- In - the second, on the sorption isotherms for the sample with the
content (8102) claim more than 70
%
is present sorption-desorption hysteresis,
the appearance of which, as mentioned earlier, due to the capillary condensation
of the water in the porous structure (8102) II. Increasing the polymer
concentration leads to its degeneration, and finally, at equal concentration of the
components in the mixture can be observed a complete coincidence sorption and
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