Dissociation course of polymethylvinyl ether of maleic acid cross-linked by polypropylene glycol (PMVE-MA with PPG) was investigated using classical potentiometric titration and colloid titration. It is assumed, that in the course of colloid titration monovalent counter-ions are replaced by the oppositely charged polycation, therefore it was determined the general concentration of anionic groups of hydrogel of polymethylvinyl ether of maleic acid cross-linked by polypropylene glycol. The apparent constant of dissociation (pseudo constant of dissociation) depends on the forming of the polyelectric complex but does not depend on the degree of dissociation. While it is known that potentiometric titration are determined by the apparent constant of dissociation that decreased simultaneously with the increase of the dissociation degree. Protons releasing from acid groups of hydrogel of polymethylvinyl ether of maleic acid cross-linked by polypropylene glycol leads to the formation of the complex with stronger cationic polyelectrolyte. Therefore, comparison of the results of potentiometric and colloid titration makes it possible to take in the information about the interrelation of acid characteristics of the surface of PMVE-MA with PPG and its functional properties. As a result we can define its application area for creation of new high-efficient composite material.

Kinetic analysis was made applying TG/DTG/HF data in nitrogen and air atmospherefor thermal decomposition of hydrogel of polymethylvinyl maleic acid ester, linked with polypropylene glycol, at different heating rates. TG/DTG/HF data were processed according to the followingkinetic models: Friedman, Flynn-Wall-Ozawa, Kissinger-Akahira-Sunose, Coates-Redfern and nonparametric kinetic method (NPK) was used, to obtain the following kinetic parameters: activationenergy and pre-exponential factor.According to the attained values of activation energy, the mechanism of degradation of the hydrogel was suggested. Values of kinetic parameters attained by different methods, are compliant to eachother. Isoconversion method is one of the methods for definition of activation energy; this methoddoes not require knowledge on analytical form of conversion function, and gives the possibility todefine the activation energy against conversion degree as well.To obtain full kinetic analysis it is necessary to process the data using non-parametric kineticmethod. Non-parametric kinetics method (NPK) of Serra, Nomen and Sempere is based upon thesuggestion that reaction velocity may be expressed as multiplication of two independent functions,f (α) and k (T). Reaction model f (α) considers the dependence of conversion degree, and k (T)considers the temperature dependence.

It was presented the analysis of various calculation methods of kinetic parameters of thermal decomposition of CO2-extracts samples that were distilled from Scabiosa ochroleuca and Scabiosa isetensis according to the data of dynamic thermogravimetry. The studies were carried out in air at different heating rates (from 5 to 25 deg/min). Experimental data of TG/DTG/HF methods were processed in accordance with the following kinetic models, namely, Friedman and Flynn-Ozawa-Wall to obtain the kinetic parameters. The use of the above mentioned models makes it possible to determine graphically the effective values of activation energy and pre-exponential factor at different heating rates of the sample and conversion degree. Non-parametric kinetic method was applied (NPK) for objective estimation of complex processes proceeding in parallel with thermal destruction. Non-parametric kinetic method (NPK) is a special approach for processing of kinetic data. Method is a new viewpoint to kinetic analysis, which is based upon rounding of results of single-stage process kinetics. Therefore, simultaneous use of data of TG/DTG/HF methods for kinetic analysis provide us with complete picture of thermal decomposition of carbonic extracts samples obtained from Scabiosa ochroleuca (cream scabious) and Scabiosa isetensis (lomelosia isetensis). In the result section of this study it is proved that the values of kinetic parameters determined by the use of different methods that correspond well with each other.

The results from thermogravimetric and kinetic studies of copolymers of polypropylene glycol maleate with acrylic acid at different molar ratios are presented. The results from conventional thermogravimetric studies are used to determine kinetic characteristics of the process of thermal decomposition, i.e., activation energy and pre-exponential factors. These parameters are determined in three ways: the Achar, Freeman–Carroll, and Sharp–Wentworth methods. Activation energies calculated using all the three methods confirm the dependence of the destruction process on the ratio of components in a synthesized copolymer. It is shown that the obtained values of the activation energies and thermodynamic characteristics allow us to predict a copolymer’s composition.

In this regard, in this work it was firstly performed the radical copolymerization of polypropyleneglycolmaleate with acrylic and methacrylic acids in various weight ratios at the initial mixture to produce polymers with high sorption properties. It was studied the influence of medium pH, the quality of the solvents on behaveior of hydrogels based on the copolymers of polypropyleneglycolmaleate with acrylic and methacrylic acids. Sensibility of hydrogels to the changes of above mentioned external factors was experimentally established.