Yelena Minayeva

Dr. Yelena Minayeva


Research Focus & Metrics

Academic Career Length

3Years (2024-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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3 October 2025 in Polymers
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GBGulsym Burkeyeva
Gulsym Burkeyeva
AKAnna Kovaleva
Anna Kovaleva
DMDanagul Muslimova
Danagul Muslimova
DHDavid Havlíček
David Havlíček
ABAbylaikhan Bolatbay
Abylaikhan Bolatbay
MNMargarita Nurmaganbetova
Margarita Nurmaganbetova
For the first time, the kinetics of isothermal curing and thermal degradation of polyethylene glycol maleate (pEGM)–based systems and their composites with mineral fillers were investigated in the presence of a benzoyl peroxide/N,N-Dimethylaniline redox-initiating system. DSC analysis revealed that the curing process at 20 °C can be described by the modified Kamal autocatalytic model; the critical degree of conversion (αc) decreases with increasing content of the unsaturated polyester pEGM and in the presence of fillers. In particular, for unfilled systems, αc was 0.77 for pEGM45 and 0.60 for pEGM60. TGA results demonstrated that higher pEGM content and the incorporation of fillers lead to increased thermal stability and residual mass, along with a reduction in the maximum decomposition rate (dTGₘₐₓ). Calculations using the Kissinger–Akahira–Sunose and Friedman methods also confirmed an increase in the activation energy of thermal degradation (Ea): EKAS was 419 kJ/mol for pEGM45 and 470 kJ/mol for pEGM60, with the highest values observed for pEGM60 systems with fillers (496 kJ/mol for SiO2 and 514 kJ/mol for CaCO3). Rheological studies employing three-interval thixotropy tests revealed the onset of thixotropic behavior upon filler addition and an increase in structure recovery after deformation of up to 56%. These findings underscore the potential of pEGM-based systems for low-temperature curing and for the design of composite materials with improved thermal resistance.

22 February 2024 in Eurasian Journal of Chemistry
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Journal Article
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LSLyazat K. Salkeyeva
Lyazat K. Salkeyeva
LPLeonid M. Pevzner
Leonid M. Pevzner
PVPavel Vojtíšek
Pavel Vojtíšek
YMYelena Minayeva
Yelena Minayeva
Pyrrole and its derivatives have attracted the attention of researchers as promising objects of practical importance in various areas of human life. Focusing on Knorr pyrrole as the most readily available pyrrole derivative, our objective was to obtain its bromo derivatives, containing an allyl bromine atom followed by phosphorylation reactions. The reaction involving bromination was carried out with 2 mol of N-bromosuccinimide per 1 mol of Knorr pyrrole 1 in carbon tetrachloride. This reaction was initiated with azobis(isobutyronitrile) and carried out at a boiling point. In acetic acid, the bromination reaction was carried out at a temperature of 38-45°C with a molar ratio of Knorr pyrrole to bromine of 1:4 and another reaction was carried out at 40-50°C with a molar ratio of Knorr pyrrole to bromine of 1:5. The bromination reaction was also performed in chloroform at 27-30°C in the presence of catalytic amounts of aluminum chloride. The same crystalline product was obtained in all cases. X-ray diffraction analysis revealed that the single crystal structure is diethyl 5-(dibromomethyl)-3-methyl-2-oxo-2,3-dihydro-1H-pyrrole-3,4-dicarboxylate 5 with two bromine atoms. This composition is identical to that of the Halbig product. It was found that the bromination of Knorr pyrrole 1 occurs stepwise with excess N-bromosuccinimide and bromine, resulting in the unsaturated lactam 5, commonly known as Halbig’s product. The true structure of product 5 was determined.

8 October 2025 in Molecules
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GBGulsym Burkeyeva
Gulsym Burkeyeva
AKAnna Kovaleva
Anna Kovaleva
ZIZhansaya Ibrayeva
Zhansaya Ibrayeva
DHDavid Havlíček
David Havlíček
YMYelena Minayeva
Yelena Minayeva
MNMargarita Nurmaganbetova
Margarita Nurmaganbetova
The rheological behavior and low-temperature curing kinetics of poly(ethylene glycol fumarate)–acrylic acid systems initiated by benzoyl peroxide/N,N-dimethylaniline have been investigated for the first time with a focus on the development of thermosetting binders with controllable properties. It has been established that both composition and temperature have a significant effect on rheological behavior and kinetic parameters. Rheological studies revealed non-Newtonian flow behavior and thixotropic properties, while oscillatory tests demonstrated structural transformations during curing. Increasing the temperature was found to accelerate gelation, whereas a higher polyester content retarded the process, which is crucial for controlling the pot life of the reactive mixture. DSC analysis indicated that isothermal curing at 30–40 °C can be satisfactorily described by the Kamal autocatalytic model, whereas at 20 °C, at later stages, and at higher polyester contents, diffusion control becomes significant. The thermal behavior of cured systems was investigated using thermogravimetry. Calculations using the isoconversional Kissinger–Akahira–Sunose and Friedman methods confirmed an increase in the apparent activation energy for thermal decomposition, suggesting a stabilizing effect of poly(ethylene glycol fumarate) in the polymer structure. The studied systems are characterized by controllable kinetics, tunable viscosity, and high thermal stability, making them promising thermosetting binders for applications in composites, construction, paints and coatings, and adhesives.