Стр. 96 - ДЛЯ ППС

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Substituting in reference data on the water activity in an ethanol solution
[14. 350] found the coefficients a, (3 and y). The thus obtained values of the
coefficients were respectively: a = 3.33, 3 = 8.51 and y = 0.51. Then, using these
values, curve was constructed for the monomer solution.
Sorption of water vapor polyelectrolytes based on polystyrene crosslinked
with various crosslinking of DVB and different types of polar groups. Isotherms
which clearly shows that sorption of water at specific in this case, affects the
amount of DVB in the polymer, and the type of the polar group in the ion
exchanger.
The results indicate that in all the cases studied, there was a link between
dependence
nw
= f
(aw)
in the monomer solution and water sorption isotherm
corresponding polymer. This relationship is described by the constant water
distribution Kd and can be traced over the entire range studied the vapor
pressure values. It is evident that under the same external conditions, PS
concentration is always greater concentration of the monomer solution.
When studying the water sorption PVA determined that the specific
amount of water, which absorbs PVA depends on the vapor pressure and does
not depend on the crosslinking. Obtained when the concentration of PVA
solution is greater than in the same conditions, the concentration of ethanol
solution, which is a monomeric analog of PVS. This difference may explain the
polymer chain influence and the influence of the fixed distance between the
polar groups in the polymer molecule. And on RP concentration affects the mass
of the polymer molecule. Of - for high molecular weight polymer chains have
on the water molecules in between, an effect similar to the action of the capillary
wall, i.e. affect the value of external pressure.
For this reason, the standard value of the chemical potential for water in the
RP will differ from the standard values of the chemical potential for water in
normal conditions. In [10] it is shown that for the same vapor pressure of water
activity concentration in the RP will differ from the corresponding values in the
usual solution. Properties of water stored in the ER and in the case where the
polymer is not water vapor in the atmosphere, and water or an aqueous solution.
This means that the polymer backbone is a water activity influences the phase of
the ER, and it leads to a decrease of pressure on the external phase. By analogy
with the capillary effect called polymer effect.
Effect of polymer reduces the effect of external pressure on the ER, and as
a consequence to a decrease in its specific equilibrium amount of water. As a
result, under the same ambient conditions, the relative vapor pressure SH
concentration is always greater than the corresponding monomer solution.
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