1 Uzbekistan, Samarkand электронный выпуск ксерогели, стекло и объёмные керамические материалы Перспективные материалы для применений в области

 
to it’s isothermical differincial avtomatical calorimeter of the type Tian-Kalve. 
Adsorption of water in nanoporous
 
hybrid nanocompositional materials is presented high 
scientifical and technical interest owing to using of these materials as sorbents in high-effective liquid 
chromatography, catalaysts, sensors, for purification of sewage from ions of heavy metals [6].
In this work correlation between molecular structure and
 
thermodynamical characteristics for 
determination of number, strange and localization of adsorption centers, structure of 
nanocompositional materials such as diacetate cellulose (DAC)-silica and polyacrilonitrile (PAN)-
silica, mechanism of adsorption of polar molecules of water, nature of intermolecular interactions, 
conformation and state of absorbited clasters and also thermokinetics of adsorption has been 
investigated [7].
Isotherms were treated by equations of theory of volume filling micropors (TVFM). Isotherms 
of water adsorption in hybrid nanocompositional materials has described in best degree by three-

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СЕКЦИЯ 4. «ГИБРИДНЫЕ НЕОРГАНИЧЕСКИЕ И ОРГАНО-
НЕОРГАНИЧЕСКИЕ ЗОЛЬ-ГЕЛЬ МАТЕРИАЛЫ» 
69 
member equations of TVFM and at this date calculated by equations are in good correlation with 
experimental data.
By equation of Gibbs-Gelmgolz the molar differential entropy of water adsorption in hybrid 
nanocompositional materials DAC-silica and PAN-silica was calculated. Values of the molar 
differential entropy have shown that station of water on surface is ice-similar (entropy of ice – 26 
J/mole∙K). Middle molar integral entropy of water adsorpted on surface of DAC-silica has equaled – 
70,3 J/mole∙K and for PAN-silica it has equlaled -36 J/mole∙K. Value of the midde-molar integral 
entropy for DAC-silica has indicated on the fact that mobility of molecules of adsorbited water is 
strongly braked in hybrid nanocomposite and in case of PAN-silica has approached to value of ice 
entropy. 
The isotherm of water adsorption in PAN-silica hybrid nanocomposite materials is satisfactory 
and fully described by the three-term equation of TOZM: 
а= 0,365 ехр [-(A/13,93)]
4
+ 2,893 exp [-(A/4,08)]
2
+ 0,625 exp [-(A/0,59)] 
Parameters of the equation: 
the fraction of the first term a
01
= 0.365 mmol/g, E
01
= 13.93 kJ/mol, n
1
= 4; 
for the second term a
02
= 2.893 mmol/g, E
02
= 4.08 kJ/mol, n
2
= 2; 
for the third term, a
03
= 0.625 mmol/g, E
03
= 0.59 kJ/mol, n
3
= 1. 
The TVFM equation could be considered as three-dimensional, where the water molecule is 
firmly located in the pore space of the hybrid PAN-silica nanocomposite. The high initial energy and 
high energy level of the interaction of water with nanocomposites indicate that water molecules 
adsorbed on a PAN-silica hybrid nanocomposite are in an ice-like state, which indicates inhibition of 
adsorbed water molecules. Further, water molecules adsorbs on nanocomposites with relatively low 
energy forms clusters, located on the surface of a PAN-silica hybrid nanocomposite. The three-term 
equation of TOZM describes the main region of adsorption by high values degree under the exponent, 
indicating a high uniformity of the sorption system [8,9]. 
TVFM involves three adsorption mechanisms: approximately 85% of the sorption space of 
hybrid nanocomposites is filled by the first mechanism, then filling another part of the sorption space, 
which differs from the first, by adsorption interaction. 
The use of the method for compensating heat fluxes by the Peltier allows to increase the 
accuracy of measuring the adsorption heat by more than an order of magnitude. Adsorption 
measurements were carried out on a universal high-vacuum volumetric equipment, which made it 
possible to carry out adsorption measurements and dosage of the adsorbate with high accuracy. 
Thus isotherms and differential heats of water adsorption by hybrid nanocompositions 
polymer – silica have been investigated. Precizional adsorptionno – calorimetrical installation was 
used. This installation besides thermodinamical characteristies has given full information about 
physical, chemical and crystallo-chemical nature of adsorbent surface and also about mechanism and 
thermokinetics of adsorption and state of adsorbate in matrixe of adsorbent. Isotherms were treated by 
equations of theory of volume filling of microporuse. Isotherm of water adsorption in hybride 
nanocompositional materials is described in good degree by equation of TVFM