Elena Chernikova - Academia.edu (original) (raw)

Papers by Elena Chernikova

Research paper thumbnail of Fiber Spinning of Polyacrylonitrile Terpolymers Containing Acrylic Acid and Alkyl Acrylates

Fibers

Terpolymers of acrylonitrile with acrylic acid and alkyl acrylates, including methyl-, butyl-, 2-... more Terpolymers of acrylonitrile with acrylic acid and alkyl acrylates, including methyl-, butyl-, 2-ethylhexyl-, and lauryl acrylates, were synthesized using the reversible addition–fragmentation chain transfer method. In this study, the focus was on the investigation of the impact of different monomer addition methods (continuous and batch) on both the rheological behavior of the spinning solutions and the mechanical properties of the resulting fibers. Our findings revealed that the method of monomer addition, leading either to non-uniform copolymers or to a uniform distribution, significantly influences the rheological properties of the concentrated solutions, surpassing the influence of the alkyl-acrylate nature alone. To determine the optimal spinning regime, we examined the morphology and mechanical properties at different stages of fiber spinning, considering spin-bond and orientation drawings. The fiber properties were found to be influenced by both the nature and introducing me...

Research paper thumbnail of Influence of Monomer Sequence on the Cyclization Behavior of Poly(acrylonitrile-co-acrylamide)

Applied Sciences

In this research, we have developed the approach to controlled synthesis of acrylonitrile-acrylam... more In this research, we have developed the approach to controlled synthesis of acrylonitrile-acrylamide copolymers with narrow molecular weight distribution and various monomer sequence distributions. By using dibenzyl trithiocarbonate and batch/semibatch polymerization, we have first synthesized random, gradient, and block-gradient copolymers containing 3.4–10.2 mol. % of acrylamide and revealed the influence of the monomer sequence on the cyclization behavior of poly(acrylonitrile-co-acrylamide) by combination of differential scanning calorimetry and Fourier transform infrared spectroscopy. This allowed us to find differences in cyclization behavior of the copolymers in argon and air atmosphere. Intramolecular cyclization was the main process proceeding in argon atmosphere. The radical mechanism of cyclization was suppressed already at the molar part of acrylamide units in copolymer exceeding ~3 mol. % for random copolymer and ~6 mol. % for block-gradient copolymer. The activation en...

Research paper thumbnail of Double Stimuli-Responsive di- and Triblock Copolymers of Poly(N-isopropylacrylamide) and Poly(1-vinylimidazole): Synthesis and Self-Assembly

International Journal of Molecular Sciences

For the first time, double stimuli-responsive properties of poly(N-isopropylacrylamide) (PNIPA) a... more For the first time, double stimuli-responsive properties of poly(N-isopropylacrylamide) (PNIPA) and poly(1-vinylimidazole) (PVIM) block copolymers in aqueous solutions were studied. The synthesis of PNIPA60-b-PVIM90 and PNIPA28-b-PVIM62-b-PNIPA29 was performed using reversible addition–fragmentation chain transfer (RAFT) polymerization. The polymers were characterized by size exclusion chromatography and 1H NMR spectroscopy. The conformational behavior of the polymers was studied using dynamic light scattering (DLS) and fluorescence spectroscopy (FS). It was found that PNIPA and block copolymers conformation and ability for self-assembly in aqueous medium below and above cloud point temperature depend on the locus of hydrophobic groups derived from the RAFT agent within the chain. Additionally, the length of PVIM block, its locus in the chain and charge perform an important role in the stabilization of macromolecular micelles and aggregates below and above cloud point temperature. A...

Research paper thumbnail of Melt-Spinnable Polyacrylonitrile—An Alternative Carbon Fiber Precursor

Polymers

The review summarizes recent advances in the production of carbon fiber precursors based on melt-... more The review summarizes recent advances in the production of carbon fiber precursors based on melt-spun acrylonitrile copolymers. Approaches to decrease the melting point of polyacrylonitrile and acrylonitrile copolymers are analyzed, including copolymerization with inert comonomers, plasticization by various solvents and additives, among them the eco-friendly ways to use the carbon dioxide and ionic liquids. The methods for preliminary modification of precursors that provides the thermal oxidative stabilization of the fibers without their melting and the reduction in the stabilization duration without the loss of the mechanical characteristics of the fibers are discussed. Special attention is paid to different ways of crosslinking by irradiation with different sources. Examples of the carbon fibers preparation from melt-processable acrylonitrile copolymers are considered in detail. A patent search was carried out and the information on the methods for producing carbon fibers from pre...

Research paper thumbnail of RAFT Copolymerization of Vinyl Acetate and Acrylic Acid in the Selective Solvent

Polymers, 2022

Reversible addition-fragmentation chain transfer polymerization was successfully applied to the s... more Reversible addition-fragmentation chain transfer polymerization was successfully applied to the synthesis of the gradient copolymer of acrylic acid and vinyl acetate in the selective solvent. The gradient degree of the copolymer was varied by the monomer feed. The monomer conversion was found to affect the ability of the copolymer to self-assemble in aqueous solutions in narrowly dispersed micelles with an average hydrodynamic radius of about 250 nm. Furthermore, the synthesized copolymers also tended to self-assemble throughout copolymerization in the selective solvent.

Research paper thumbnail of Monochelic Versus Telechelic Poly(Methyl Methacrylate) as a Matrix for Photoluminescent Nanocomposites with Quantum Dots

Molecules, 2021

Nanocomposites based on CdSe or CdSe/ZnS quantum dots (QDs) and poly(methyl methacrylate) (PMMA) ... more Nanocomposites based on CdSe or CdSe/ZnS quantum dots (QDs) and poly(methyl methacrylate) (PMMA) of different molecular weights and functionality were synthesized by ligand exchange of oleic acid with RAFT-based PMMA. The successful ligand exchange was confirmed by dynamic light scattering in combination with the approach “macromolecules—ghosts” and transmission electron microscopy. Comparative study of mono- and telechelics of PMMA revealed the similarities and differences in their behavior in formation of complexes with QDs and the optical properties of the corresponding nanocomposites. Telechelics exhibited higher efficiency in the complex formation and seemed to be promising candidates for the construction of devices based on QDs and polymer matrix for optical applications.

Research paper thumbnail of Thematic course: Control over physical and chemical properties of polymers by direct synthesis. Part 1. Influence of the nature of the co-monomer on the thermal behavior of acrylonitrile co-polymers

We studied the laws of the formation of actylonitrile co-polymers in the presence of small additi... more We studied the laws of the formation of actylonitrile co-polymers in the presence of small additions of co-monomers - styrene and tret-butylacrylate - in pseudoliving radical polymerization under the action of agents of reversible chain-transfer. The influence of the nature of co-monomer on the rate of formation and the structure of polyconjugated system under the thermal effect on the synthesized co-polymers have been studied.

Research paper thumbnail of Radical Replacement of the Dithiocarbonyl Group of Poly(methyl methacrylate) Obtained by Reversible Addition–FragmentationChain Transfer Polymerization

The authors perform a systematic study of the reaction of radical replacement of the dithiocarbon... more The authors perform a systematic study of the reaction of radical replacement of the dithiocarbonyl group of poly(methyl methacrylate) (PMMA) obtained by reversible addition–fragmentation chain transfer polymerization upon interaction with a radical azo initiator in an inert solvent at 80°C. It is shown that, for a polymer with a dithiobenzoate group, an increase in the molar ratio of the concentrations of the initiator and macromolecules with a terminal dithiobenzoate group to 100 equivalents promotes fast and quantitative replacement of the dithiobenzoate group by the initiator fragment and suppression of side chain termination reactions with the participation of radical intermediates. To replace the trithiocarbonate group, milder conditions are required, namely, a 20-fold molar excess of the initiator and a short reaction time of 2–5 h. The stability of the radical intermediates plays the decisive role in choosing the replacement reaction conditions. The reversible chain transfer...

Research paper thumbnail of The Effect of the Synthetic Procedure of Acrylonitrile–Acrylic Acid Copolymers on Rheological Properties of Solutions and Features of Fiber Spinning

Materials, 2020

The influence of introducing acrylic acid (AA) into the reaction mixture with acrylonitrile at th... more The influence of introducing acrylic acid (AA) into the reaction mixture with acrylonitrile at the synthesis of copolymers by free-radical polymerization (FRP) and radical polymerization with reversible addition–fragmentation chain transfer (RAFT) on the rheological properties of their solutions in dimethyl sulfoxide, as well as on the capability to spin fibers by the mechanotropic method, is analyzed. The influence of AA dosing conditions on the rheological properties of the solutions in the concentration range above the crossover point was not revealed. In the case of RAFT synthesis, the rheological properties differ distinctively in the high concentration region that is expressed by unusual viscoelastic characteristics. Dilute solution viscometry revealed the influence of the comonomer loading order on the interaction intensity of the copolymer macromolecules with a solvent, which is more pronounced for samples synthesized by FRP and can be associated with the copolymers’ molecul...

Research paper thumbnail of Control over the relative reactivities of monomers in RAFT copolymerization of styrene and acrylic acid

RSC Advances, 2018

The tuning of the relative monomer reactivities of styrene and acrylic acid in a solution of N,N-... more The tuning of the relative monomer reactivities of styrene and acrylic acid in a solution of N,N-dimethylformamide by using polymeric RAFT agents.

Research paper thumbnail of Surface properties of poly(styrene-co-n-butyl acrylate) binary copolymers: Effect of chain microstructure and composition

Russian Journal of Physical Chemistry A, 2015

The regularities of changing of surface energy characteristics of poly(styrene-con -butyl acrylat... more The regularities of changing of surface energy characteristics of poly(styrene-con -butyl acrylate) binary copolymers films at varying of chain microstructure, composition and thermodynamic quality of solvent, from which films are formed, with respect to comonomers, were detected. The concordance between the information about characteristics of films surfaces, obtained via contact angle measurements and ATR-FTIR spectroscopy was observed. The type of polymer chain microstructure, provided the best adhesion properties of copolymers with respect to polar phases was detected.

Research paper thumbnail of Influence of chain microstructure of acrylic acid and 4-vinylpyridine copolymers on their aggregative stability and adsorption from aqueous solutions

Polymer Science, Series C, 2017

The behavior of acrylic acid-4-vinylpyridine copolymers of different architectures, namely, with ... more The behavior of acrylic acid-4-vinylpyridine copolymers of different architectures, namely, with gradient and block distributions of comonomer units in a chain as well as with quaternized 4-vinylpyridine units, is studied. It is shown that all the copolymers are prone to aggregation in acidic and alkaline media and that the sizes of aggregates and the regions of their stability are determined by chain microstructure. The aggregates formed in acidic media exhibit temperature sensitivity. The kinetics and mechanism of copolymer adsorption from solutions on the surface of nylon membranes are explored. It is shown that the block distribution of units substantially increases the adsorption efficiency, while the quaternization of 4-vinylpyridine units decreases the monolayer adsorption parameters.

Research paper thumbnail of Liquid crystalline side-chain triblock copolymers consisting of a nematic central subblock edged by photochromic azobenzene-containing fragments: their synthesis, structure and photooptical behaviour

Polymer Chemistry, 2015

Synthesis, phase and photooptical properties of new symmetrical fully liquid crystalline triblock... more Synthesis, phase and photooptical properties of new symmetrical fully liquid crystalline triblock copolymers.

Research paper thumbnail of Controlled copolymerization of acrylonitrile in bulk via the reversible addition-fragmentation chain-transfer mechanism

Polymer Science Series B, 2014

The pseudoliving radical binary copolymerization of acrylonitrile with methyl acrylate, styrene, ... more The pseudoliving radical binary copolymerization of acrylonitrile with methyl acrylate, styrene, n butyl acrylate, and tert butyl acrylate in bulk in the presence of the reversible addition fragmentation chain transfer agent dibenzyl trithiocarbonate is performed for the first time. The addition of trithiocarbon ate makes it possible to prepare a narrowly dispersed visually optically transparent copolymer in a wide range of monomer feed compositions even at limiting conversions. Conditions for the synthesis of acrylonitrile copolymers with controlled molecular masses and narrow molecular mass distributions are ascertained. In the above copolymers, the trithiocarbonate group is shown to be located within the chain.

Research paper thumbnail of Thermal stability of styrene/n-butyl acrylate RAFT-based copolymers

Polymer Chemistry, 2016

Homopolymer of n-butyl acrylate and styrene/n-butyl acrylate copolymers, where n-butyl acrylate u... more Homopolymer of n-butyl acrylate and styrene/n-butyl acrylate copolymers, where n-butyl acrylate units are linked to the trithiocarbonate group, are more thermally stable as compared with homopolymer of styrene and similar copolymers containing styrene units linked to this group.

Research paper thumbnail of Direct determination of the inhibition rate constant in the nitroxide-mediated pseudoliving radical polymerization of styrene

Polymer Science Series B, 2001

Research paper thumbnail of RAFT重合による有機,有機および水性媒体中でのアクリル酸,アクリル酸フルオロアルキルとアクリル酸n‐ブチルに基づく両親媒性共重合体の合成【Powered by NICT】

Research paper thumbnail of Pseudoliving radical polymerization of methyl methacrylate in the presence of azobisisobutyronitrile and hexaphenylethane

Polymer Science Series B, 1998

The kinetics of the radical polymerization of methyl methacrylate initiated by an AIBN-hexaphenyl... more The kinetics of the radical polymerization of methyl methacrylate initiated by an AIBN-hexaphenylethane initiating system was studied, and the molecular mass characteristics of the resulting polymers were investigated within the entire range of monomer conversions. It was found that, when hexaphenylethane was in excess with respect to AIBN, the mechanism of polymerization changed to pseudoliving, and the process was characterized by a successive increase in the molecular mass of the polymers and by suppression of the gel effect at high conversions.

Research paper thumbnail of Regularities of the kinetics of miniemulsion polymerization of styrene in the presence of dithiobenzoates as reversible chain transfer agents

Russian Chemical Bulletin, 2015

The results of comparative kinetic study of the miniemulsion controlled radical polymer ization o... more The results of comparative kinetic study of the miniemulsion controlled radical polymer ization of styrene in the presence of reversible chain transfer agents (benzyl dithiobenzoate and polystyrene dithiobenzoate) and bulk polymerization of similar systems are presented. The influence of the reactant nature and dithiobenzoate concentration of the kinetics of the process is discussed.

Research paper thumbnail of Amphiphilic Triblock Copolymers Based on Acrylic Acid and Alkyl Acrylates Synthesized via RAFT Polymerization-Induced Self-Assembly and RAFT Miniemulsion Polymerization

Polymer Science, Series B, 2018

The aim of this research is to reveal the advantages and limitations of different heterophase pol... more The aim of this research is to reveal the advantages and limitations of different heterophase polymerization methods, such as dispersion, emulsifier-free emulsion and miniemulsion polymerization, for the obtaining of in situ self-assembled amphiphilic triblock copolymer core-shell particles. In the present research, we addressed the problems of the controlled synthesis of two-and three-component amphiphilic ABA triblock copolymers based on acrylic acid, fluoroalkyl acrylates and butyl acrylate via polymerizationinduced self-assembly and reversible addition fragmentation chain transfer polymerization (RAFT) miniemulsion polymerization using symmetrical trithiocarbonates.

Research paper thumbnail of Fiber Spinning of Polyacrylonitrile Terpolymers Containing Acrylic Acid and Alkyl Acrylates

Fibers

Terpolymers of acrylonitrile with acrylic acid and alkyl acrylates, including methyl-, butyl-, 2-... more Terpolymers of acrylonitrile with acrylic acid and alkyl acrylates, including methyl-, butyl-, 2-ethylhexyl-, and lauryl acrylates, were synthesized using the reversible addition–fragmentation chain transfer method. In this study, the focus was on the investigation of the impact of different monomer addition methods (continuous and batch) on both the rheological behavior of the spinning solutions and the mechanical properties of the resulting fibers. Our findings revealed that the method of monomer addition, leading either to non-uniform copolymers or to a uniform distribution, significantly influences the rheological properties of the concentrated solutions, surpassing the influence of the alkyl-acrylate nature alone. To determine the optimal spinning regime, we examined the morphology and mechanical properties at different stages of fiber spinning, considering spin-bond and orientation drawings. The fiber properties were found to be influenced by both the nature and introducing me...

Research paper thumbnail of Influence of Monomer Sequence on the Cyclization Behavior of Poly(acrylonitrile-co-acrylamide)

Applied Sciences

In this research, we have developed the approach to controlled synthesis of acrylonitrile-acrylam... more In this research, we have developed the approach to controlled synthesis of acrylonitrile-acrylamide copolymers with narrow molecular weight distribution and various monomer sequence distributions. By using dibenzyl trithiocarbonate and batch/semibatch polymerization, we have first synthesized random, gradient, and block-gradient copolymers containing 3.4–10.2 mol. % of acrylamide and revealed the influence of the monomer sequence on the cyclization behavior of poly(acrylonitrile-co-acrylamide) by combination of differential scanning calorimetry and Fourier transform infrared spectroscopy. This allowed us to find differences in cyclization behavior of the copolymers in argon and air atmosphere. Intramolecular cyclization was the main process proceeding in argon atmosphere. The radical mechanism of cyclization was suppressed already at the molar part of acrylamide units in copolymer exceeding ~3 mol. % for random copolymer and ~6 mol. % for block-gradient copolymer. The activation en...

Research paper thumbnail of Double Stimuli-Responsive di- and Triblock Copolymers of Poly(N-isopropylacrylamide) and Poly(1-vinylimidazole): Synthesis and Self-Assembly

International Journal of Molecular Sciences

For the first time, double stimuli-responsive properties of poly(N-isopropylacrylamide) (PNIPA) a... more For the first time, double stimuli-responsive properties of poly(N-isopropylacrylamide) (PNIPA) and poly(1-vinylimidazole) (PVIM) block copolymers in aqueous solutions were studied. The synthesis of PNIPA60-b-PVIM90 and PNIPA28-b-PVIM62-b-PNIPA29 was performed using reversible addition–fragmentation chain transfer (RAFT) polymerization. The polymers were characterized by size exclusion chromatography and 1H NMR spectroscopy. The conformational behavior of the polymers was studied using dynamic light scattering (DLS) and fluorescence spectroscopy (FS). It was found that PNIPA and block copolymers conformation and ability for self-assembly in aqueous medium below and above cloud point temperature depend on the locus of hydrophobic groups derived from the RAFT agent within the chain. Additionally, the length of PVIM block, its locus in the chain and charge perform an important role in the stabilization of macromolecular micelles and aggregates below and above cloud point temperature. A...

Research paper thumbnail of Melt-Spinnable Polyacrylonitrile—An Alternative Carbon Fiber Precursor

Polymers

The review summarizes recent advances in the production of carbon fiber precursors based on melt-... more The review summarizes recent advances in the production of carbon fiber precursors based on melt-spun acrylonitrile copolymers. Approaches to decrease the melting point of polyacrylonitrile and acrylonitrile copolymers are analyzed, including copolymerization with inert comonomers, plasticization by various solvents and additives, among them the eco-friendly ways to use the carbon dioxide and ionic liquids. The methods for preliminary modification of precursors that provides the thermal oxidative stabilization of the fibers without their melting and the reduction in the stabilization duration without the loss of the mechanical characteristics of the fibers are discussed. Special attention is paid to different ways of crosslinking by irradiation with different sources. Examples of the carbon fibers preparation from melt-processable acrylonitrile copolymers are considered in detail. A patent search was carried out and the information on the methods for producing carbon fibers from pre...

Research paper thumbnail of RAFT Copolymerization of Vinyl Acetate and Acrylic Acid in the Selective Solvent

Polymers, 2022

Reversible addition-fragmentation chain transfer polymerization was successfully applied to the s... more Reversible addition-fragmentation chain transfer polymerization was successfully applied to the synthesis of the gradient copolymer of acrylic acid and vinyl acetate in the selective solvent. The gradient degree of the copolymer was varied by the monomer feed. The monomer conversion was found to affect the ability of the copolymer to self-assemble in aqueous solutions in narrowly dispersed micelles with an average hydrodynamic radius of about 250 nm. Furthermore, the synthesized copolymers also tended to self-assemble throughout copolymerization in the selective solvent.

Research paper thumbnail of Monochelic Versus Telechelic Poly(Methyl Methacrylate) as a Matrix for Photoluminescent Nanocomposites with Quantum Dots

Molecules, 2021

Nanocomposites based on CdSe or CdSe/ZnS quantum dots (QDs) and poly(methyl methacrylate) (PMMA) ... more Nanocomposites based on CdSe or CdSe/ZnS quantum dots (QDs) and poly(methyl methacrylate) (PMMA) of different molecular weights and functionality were synthesized by ligand exchange of oleic acid with RAFT-based PMMA. The successful ligand exchange was confirmed by dynamic light scattering in combination with the approach “macromolecules—ghosts” and transmission electron microscopy. Comparative study of mono- and telechelics of PMMA revealed the similarities and differences in their behavior in formation of complexes with QDs and the optical properties of the corresponding nanocomposites. Telechelics exhibited higher efficiency in the complex formation and seemed to be promising candidates for the construction of devices based on QDs and polymer matrix for optical applications.

Research paper thumbnail of Thematic course: Control over physical and chemical properties of polymers by direct synthesis. Part 1. Influence of the nature of the co-monomer on the thermal behavior of acrylonitrile co-polymers

We studied the laws of the formation of actylonitrile co-polymers in the presence of small additi... more We studied the laws of the formation of actylonitrile co-polymers in the presence of small additions of co-monomers - styrene and tret-butylacrylate - in pseudoliving radical polymerization under the action of agents of reversible chain-transfer. The influence of the nature of co-monomer on the rate of formation and the structure of polyconjugated system under the thermal effect on the synthesized co-polymers have been studied.

Research paper thumbnail of Radical Replacement of the Dithiocarbonyl Group of Poly(methyl methacrylate) Obtained by Reversible Addition–FragmentationChain Transfer Polymerization

The authors perform a systematic study of the reaction of radical replacement of the dithiocarbon... more The authors perform a systematic study of the reaction of radical replacement of the dithiocarbonyl group of poly(methyl methacrylate) (PMMA) obtained by reversible addition–fragmentation chain transfer polymerization upon interaction with a radical azo initiator in an inert solvent at 80°C. It is shown that, for a polymer with a dithiobenzoate group, an increase in the molar ratio of the concentrations of the initiator and macromolecules with a terminal dithiobenzoate group to 100 equivalents promotes fast and quantitative replacement of the dithiobenzoate group by the initiator fragment and suppression of side chain termination reactions with the participation of radical intermediates. To replace the trithiocarbonate group, milder conditions are required, namely, a 20-fold molar excess of the initiator and a short reaction time of 2–5 h. The stability of the radical intermediates plays the decisive role in choosing the replacement reaction conditions. The reversible chain transfer...

Research paper thumbnail of The Effect of the Synthetic Procedure of Acrylonitrile–Acrylic Acid Copolymers on Rheological Properties of Solutions and Features of Fiber Spinning

Materials, 2020

The influence of introducing acrylic acid (AA) into the reaction mixture with acrylonitrile at th... more The influence of introducing acrylic acid (AA) into the reaction mixture with acrylonitrile at the synthesis of copolymers by free-radical polymerization (FRP) and radical polymerization with reversible addition–fragmentation chain transfer (RAFT) on the rheological properties of their solutions in dimethyl sulfoxide, as well as on the capability to spin fibers by the mechanotropic method, is analyzed. The influence of AA dosing conditions on the rheological properties of the solutions in the concentration range above the crossover point was not revealed. In the case of RAFT synthesis, the rheological properties differ distinctively in the high concentration region that is expressed by unusual viscoelastic characteristics. Dilute solution viscometry revealed the influence of the comonomer loading order on the interaction intensity of the copolymer macromolecules with a solvent, which is more pronounced for samples synthesized by FRP and can be associated with the copolymers’ molecul...

Research paper thumbnail of Control over the relative reactivities of monomers in RAFT copolymerization of styrene and acrylic acid

RSC Advances, 2018

The tuning of the relative monomer reactivities of styrene and acrylic acid in a solution of N,N-... more The tuning of the relative monomer reactivities of styrene and acrylic acid in a solution of N,N-dimethylformamide by using polymeric RAFT agents.

Research paper thumbnail of Surface properties of poly(styrene-co-n-butyl acrylate) binary copolymers: Effect of chain microstructure and composition

Russian Journal of Physical Chemistry A, 2015

The regularities of changing of surface energy characteristics of poly(styrene-con -butyl acrylat... more The regularities of changing of surface energy characteristics of poly(styrene-con -butyl acrylate) binary copolymers films at varying of chain microstructure, composition and thermodynamic quality of solvent, from which films are formed, with respect to comonomers, were detected. The concordance between the information about characteristics of films surfaces, obtained via contact angle measurements and ATR-FTIR spectroscopy was observed. The type of polymer chain microstructure, provided the best adhesion properties of copolymers with respect to polar phases was detected.

Research paper thumbnail of Influence of chain microstructure of acrylic acid and 4-vinylpyridine copolymers on their aggregative stability and adsorption from aqueous solutions

Polymer Science, Series C, 2017

The behavior of acrylic acid-4-vinylpyridine copolymers of different architectures, namely, with ... more The behavior of acrylic acid-4-vinylpyridine copolymers of different architectures, namely, with gradient and block distributions of comonomer units in a chain as well as with quaternized 4-vinylpyridine units, is studied. It is shown that all the copolymers are prone to aggregation in acidic and alkaline media and that the sizes of aggregates and the regions of their stability are determined by chain microstructure. The aggregates formed in acidic media exhibit temperature sensitivity. The kinetics and mechanism of copolymer adsorption from solutions on the surface of nylon membranes are explored. It is shown that the block distribution of units substantially increases the adsorption efficiency, while the quaternization of 4-vinylpyridine units decreases the monolayer adsorption parameters.

Research paper thumbnail of Liquid crystalline side-chain triblock copolymers consisting of a nematic central subblock edged by photochromic azobenzene-containing fragments: their synthesis, structure and photooptical behaviour

Polymer Chemistry, 2015

Synthesis, phase and photooptical properties of new symmetrical fully liquid crystalline triblock... more Synthesis, phase and photooptical properties of new symmetrical fully liquid crystalline triblock copolymers.

Research paper thumbnail of Controlled copolymerization of acrylonitrile in bulk via the reversible addition-fragmentation chain-transfer mechanism

Polymer Science Series B, 2014

The pseudoliving radical binary copolymerization of acrylonitrile with methyl acrylate, styrene, ... more The pseudoliving radical binary copolymerization of acrylonitrile with methyl acrylate, styrene, n butyl acrylate, and tert butyl acrylate in bulk in the presence of the reversible addition fragmentation chain transfer agent dibenzyl trithiocarbonate is performed for the first time. The addition of trithiocarbon ate makes it possible to prepare a narrowly dispersed visually optically transparent copolymer in a wide range of monomer feed compositions even at limiting conversions. Conditions for the synthesis of acrylonitrile copolymers with controlled molecular masses and narrow molecular mass distributions are ascertained. In the above copolymers, the trithiocarbonate group is shown to be located within the chain.

Research paper thumbnail of Thermal stability of styrene/n-butyl acrylate RAFT-based copolymers

Polymer Chemistry, 2016

Homopolymer of n-butyl acrylate and styrene/n-butyl acrylate copolymers, where n-butyl acrylate u... more Homopolymer of n-butyl acrylate and styrene/n-butyl acrylate copolymers, where n-butyl acrylate units are linked to the trithiocarbonate group, are more thermally stable as compared with homopolymer of styrene and similar copolymers containing styrene units linked to this group.

Research paper thumbnail of Direct determination of the inhibition rate constant in the nitroxide-mediated pseudoliving radical polymerization of styrene

Polymer Science Series B, 2001

Research paper thumbnail of RAFT重合による有機,有機および水性媒体中でのアクリル酸,アクリル酸フルオロアルキルとアクリル酸n‐ブチルに基づく両親媒性共重合体の合成【Powered by NICT】

Research paper thumbnail of Pseudoliving radical polymerization of methyl methacrylate in the presence of azobisisobutyronitrile and hexaphenylethane

Polymer Science Series B, 1998

The kinetics of the radical polymerization of methyl methacrylate initiated by an AIBN-hexaphenyl... more The kinetics of the radical polymerization of methyl methacrylate initiated by an AIBN-hexaphenylethane initiating system was studied, and the molecular mass characteristics of the resulting polymers were investigated within the entire range of monomer conversions. It was found that, when hexaphenylethane was in excess with respect to AIBN, the mechanism of polymerization changed to pseudoliving, and the process was characterized by a successive increase in the molecular mass of the polymers and by suppression of the gel effect at high conversions.

Research paper thumbnail of Regularities of the kinetics of miniemulsion polymerization of styrene in the presence of dithiobenzoates as reversible chain transfer agents

Russian Chemical Bulletin, 2015

The results of comparative kinetic study of the miniemulsion controlled radical polymer ization o... more The results of comparative kinetic study of the miniemulsion controlled radical polymer ization of styrene in the presence of reversible chain transfer agents (benzyl dithiobenzoate and polystyrene dithiobenzoate) and bulk polymerization of similar systems are presented. The influence of the reactant nature and dithiobenzoate concentration of the kinetics of the process is discussed.

Research paper thumbnail of Amphiphilic Triblock Copolymers Based on Acrylic Acid and Alkyl Acrylates Synthesized via RAFT Polymerization-Induced Self-Assembly and RAFT Miniemulsion Polymerization

Polymer Science, Series B, 2018

The aim of this research is to reveal the advantages and limitations of different heterophase pol... more The aim of this research is to reveal the advantages and limitations of different heterophase polymerization methods, such as dispersion, emulsifier-free emulsion and miniemulsion polymerization, for the obtaining of in situ self-assembled amphiphilic triblock copolymer core-shell particles. In the present research, we addressed the problems of the controlled synthesis of two-and three-component amphiphilic ABA triblock copolymers based on acrylic acid, fluoroalkyl acrylates and butyl acrylate via polymerizationinduced self-assembly and reversible addition fragmentation chain transfer polymerization (RAFT) miniemulsion polymerization using symmetrical trithiocarbonates.