Papers by Natalia Kazantseva
Polymers
The aim of this study was to develop a novel amikacin (AMI) delivery system with prolonged releas... more The aim of this study was to develop a novel amikacin (AMI) delivery system with prolonged release based on composite electrospun nanofibers of PLA supplemented with AMI-loaded Si nanoparticles of different morphology. The resultant materials were characterized in terms of their physical properties (scanning electron microscopy, Brunauer–Emmett–Teller analysis, thermogravimetric analysis, water contact angle). High-Performance Liquid Chromatography was used to determine the AMI content in the liquid fractions obtained from the release study. The results show that nanofibers of fumed silica exhibited an aggregated, highly porous structure, whereas nanofibers of mesoporous silica had a spherical morphology. Both silica nanoparticles had a significant effect on the hydrophilic properties of PLA nanofiber surfaces. The liquid fractions were investigated to gauge the encapsulation efficiency (EE) and loading efficiency (LE) of AMI, demonstrating 66% EE and 52% LE for nanofibers of fumed ...
Journal of Electronic Materials, 2020
Conductive polymers, such as polyaniline (PANI) and polypyrrole (PPy), are widely used in the des... more Conductive polymers, such as polyaniline (PANI) and polypyrrole (PPy), are widely used in the design of supercapacitors because of their high pseudocapacitive performance as well as facile synthesis and low cost. In this study, hybrid aerogels based on reduced graphene oxide and ZnMn2O4 were modified by PANI and PPy. The 3D structure of the hybrid aerogels was obtained by using a one-step hydrothermal co-assembly method. Then, aniline and pyrrole were polymerized on and within the structure of the hybrid aerogel through in situ polymerization. The electrochemical properties of the hybrid aerogels were studied via cyclic voltammetry and galvanostatic charge-discharge testing to identify the effects of conductive polymers on the electrochemical properties of materials. It has been established that PANI and PPy facilitate an increase of the specific capacitance of rGO/ZnMn2O4 aerogels up to 297.8 F/ g and 108.24 F/g at 0.2 A/g scan rate, respectively.
Journal of Applied Polymer Science, 2020
A porous polylactic acid (PLA) film was investigated as a separator for supercapacitors (SCs) and... more A porous polylactic acid (PLA) film was investigated as a separator for supercapacitors (SCs) and compared with commercial separators, for example, NKK‐MPF30AC and Celgard 2400. The porous PLA film was fabricated via a facile phase inversion method, and the cross‐sectional scanning electron microscope images of the PLA separator film exhibited highly porous interconnected morphology for ion diffusion. The surface modification of separators was performed by radio frequency (RF) air plasma to improve wettability. The plasma modification enhanced the water uptake and swelling properties of the separators and decreased the water contact angles of PLA and Celgard 2400 films. The mechanical and dielectric properties of separators were also studied. The ionic conductivities of RF‐PLA in 1 M H2SO4 and 1 M Na2SO4 were found to be 1.1 × 10−1 S/cm and 0.6 × 10−2 S/cm at room temperature, respectively. The electrochemical impedance spectroscopy of the RF‐PLA SCs showed the lowest solution resis...
Acta Physica Polonica A, 2017
A novel frequency selective surface for expansion of operating frequency range of magnetic-type r... more A novel frequency selective surface for expansion of operating frequency range of magnetic-type radio absorbers was elaborated. Frequency selective surface represents an array of flat electrically conductive elements deposited on the polyethylene terephthalate (PET) foil. The elements have a closed-loop structure on the one side of the foil, and on the opposite side, the conductive elements have the shape of solid fragments which connect projections of the neighboring closed loops. The advantage of such frequency selective surface design is that owing to capacitive shunting one can achieve the value of frequency selective surface quality factor (Q-factor) as low as 0.5. Operating frequency range and thickness of designed radio absorbers depend on the composition of polymer-magnetic material and the position of frequency selective surface therein.
Journal of Applied Polymer Science, 2017
ABSTRACTThis article deals with enhancement of the toughness of epoxy resin (ER) based on diglyci... more ABSTRACTThis article deals with enhancement of the toughness of epoxy resin (ER) based on diglycidyl ether bisfenol A by either polydimethylsiloxane (PDMS) or vinyl‐terminated polydimethylsiloxane (VT‐PDMS). To improve the compatibility of these two phases, dicumylperoxide (DCP) was used as a compatibilizer. It was established that only specific composition of the components can lead to enhancement of ER toughness without significant reduction of storage modulus, Tg, and interphase adhesion. The highest impact strength was recorded for ER with VT‐PDMS (10 wt %) and DCP (2 wt %) due to increased interfacial compatibility between two phases, which was proved by 1H NMR and dielectric spectroscopy. Critical ductile brittle transition occurring between 10 and 15 wt % of rubber was observed by both morphological and dynamic mechanical analysis studies. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45720.
Synthetic Metals, 2016
Polyaniline-maghemite (PANI-g-Fe 2 O 3) based dispersion has been prepared in several steps. Firs... more Polyaniline-maghemite (PANI-g-Fe 2 O 3) based dispersion has been prepared in several steps. First, iron oxide nanoparticles with mixed-phase composition were synthesized by coprecipitation method. Second, obtained particles were transformed to g-Fe 2 O 3 with sodium hypochlorite. Finally, aniline hydrochloride was in-situ polymerized with ammonium peroxydisulfate in the presence of g-Fe 2 O 3 particles in aqueous solution of poly(N-vinylpyrrolidone). Colloidal PANI-g-Fe 2 O 3 hybrid particles have average size of about 350 nm and the dispersity between 0.12 and 0.38. Hybrid dispersions with different concentration of conducting phase were characterized by electron microscopy, dynamic light scattering, UV-vis spectroscopy, thermogravimetric analysis, magnetization curve and conductivity measurements, as well as dielectric spectroscopy. Cytotoxicity on mouse embryonic fibroblast cell of PANI-g-Fe 2 O 3 colloid has been investigated. 2016 Elsevier B.V. All rights reserved.
Polymer Composites, 2014
ABSTRACT The objective of this work is to study the effect of electrical conductivity and physica... more ABSTRACT The objective of this work is to study the effect of electrical conductivity and physical-mechanical properties of carbon black (CB) filled polymer composites. This goal is achieved by synthesizing epoxy/silicon phase separated blend structure of composites filled with CB. The percolation threshold of epoxy/silicone/CB composites decreased and the total conductivity increased compared to the pure epoxy/CB composite. A threefold increase was obtained with tensile strength of epoxy/silicone/CB composite with 25 wt% of silicone and 5 wt% of CB in comparison with epoxy/CB systems. This composite has conductivity of about 10−6 S/cm, which is six orders of magnitude higher than for epoxy/CB composites at the same concentration of CB. POLYM. COMPOS., 2014. © 2014 Society of Plastics Engineers
Physics of the Solid State, 2012
Different forms of an electrically conductive polymer, an organic semiconductor, namely, polya ni... more Different forms of an electrically conductive polymer, an organic semiconductor, namely, polya niline, have been synthesized and characterized. The magnetization curves of the obtained forms have been analyzed. It has been found that, in the oxidized form, the material exhibits a magnetic hysteresis at room temperature. For polyaniline without a special doping with magnetic additives, this result has been obtained for the first time. The possibility of controlling the magnetic properties of the material by means of chemical treatment at the post polymerization stage has been demonstrated.
Journal of Communications Technology and Electronics, 2011
A detailed study of the efficiency of frequency selective surfaces for extension of the operating... more A detailed study of the efficiency of frequency selective surfaces for extension of the operating fre quency range of a dielectric radio absorber is presented. The radio absorber is fabricated from the layer of a homogeneous carbon black filled material and a frequency selective surface made of thin metal rings placed inside or on the surface of the absorber. It is shown theoretically and experimentally that insertion of a fre quency selective surface into a dielectric radio absorber makes it possible to almost double the range of oper ating frequencies without increasing the thickness of the absorber.
Composites Part A: Applied Science and Manufacturing, 2007
Electromagnetic properties of polymer composites based on different types of carbonyl iron (CI) a... more Electromagnetic properties of polymer composites based on different types of carbonyl iron (CI) are investigated in the frequency range from 1MHz to 10GHz. A significant difference in the high frequency permeability of composites filled with primary and processed CI powders is revealed, although the chemical composition and particle size distribution of these powders show small difference. Composites based on processed
Batteries
Innovation in the design of Li-ion rechargeable batteries is necessary to overcome safety concern... more Innovation in the design of Li-ion rechargeable batteries is necessary to overcome safety concerns and meet energy demands. In this regard, a new generation of Li-ion batteries (LIBs) in the form of all-solid-state batteries (ASSBs) has been developed, attracting a great deal of attention for their high-energy density and excellent mechanical-electrochemical stability. This review describes the current state of research and development on ASSB technology. To this end, study of the literature and patents as well as market analysis over the last two decades were carried out, highlighting how scientific achievements have informed the application of commercially profitable ASSBs. Analyzing the patents registered over the past 20 years revealed that the number of them had increased exponentially-from only few per year in early 2000 to more than 342 in 2020. Published literature and patents on the topic declare a solid-state electrolyte (SSE) to be the main component of ASSBs, and most pa...
Molecules
Whey protein isolate (WPI), employed as a carrier for a wide range of bioactive substances, suffe... more Whey protein isolate (WPI), employed as a carrier for a wide range of bioactive substances, suffers from a lack of colloidal stability in physiological conditions. Herein, we developed innovative stabilized PolyElectrolyte Nanoparticles (PENs) obtained by two techniques: polyelectrolyte complexation of negatively charged WPI and positively charged chitosan (CS), and ionic gelation in the presence of polyanion tripolyphosphate (TPP). Therefore, the WPI-based core was coated with a CS-based shell and then stabilized by TPP at pH 8. The nanostructures were characterized by physiochemical methods, and their encapsulation efficiency and in vitro release were evaluated. The spherical NPs with an average size of 248.57 ± 5.00 nm and surface charge of +10.80 ± 0.43 mV demonstrated high encapsulation efficiency (92.79 ± 0.69) and sustained release of a positively charged chemotherapeutic agent such as doxorubicin (DOX). Z-average size and size distribution also presented negligible increases...
International Journal of Molecular Sciences
The electrochemical parameters of a novel binder-free self-standing biomimetic cathode based on l... more The electrochemical parameters of a novel binder-free self-standing biomimetic cathode based on lithium manganese oxide (LMO) and carbon nanotubes (CNT) for rechargeable Lithium-ion aqueous batteries (ReLIAB) are improved using polyaniline (PANI) core-shell in situ polymerization and graphene (Gr). The fabricated cathode material exhibits the so-called “tectonic plate island bridge” biomimetic structure. This constitution is created by combining three components as shown by a SEM and a TEM analysis: the Gr substrates support an entangled matrix of conductive CNT which connect island of non-conductive inorganic material composed of LMO. The typical spinel structure of the LMO remains unchanged after modifying the basic structure with Gr and PANI due to a simplified hydrothermal method used for synthesis. The Gr and PANI core-shell coating improves the electric conductivity from 0.0025 S/cm up to 1 S/cm. The electrochemical performances of the LMO/CNT-Gr/PANI composite electrode are o...
Nanomaterials, 2019
In this work, a facile two-step strategy is adopted to construct hierarchical polyaniline/NiCo-la... more In this work, a facile two-step strategy is adopted to construct hierarchical polyaniline/NiCo-layered double hydroxide (PANI/NiCo-LDH) core-shell composite nanofiber networks on carbon cloth (CC). Three-dimensional (3D) porous PANI nanofiber networks are firstly uniformly anchored on CC by in-situ oxidative polymerization, followed by growth of NiCo-LDH nanoflakes on the crosslinked PANI framework via electrochemical deposition. The morphology and electrochemical properties of PANI/NiCo-LDH composites are controlled by the deposition time of LDH. Benefiting from rapid electron transport and ion diffusion, the well-defined PANI/NiCo-LDH hierarchical composite with 200 s deposition of LDH delivers a large capacitance of 1845 F g−1 at 0.5 A g−1 and excellent cycling stability of 82% capacitance retention after 5000 cycles at a very high current density of 10.0 A g−1. Furthermore, an asymmetric supercapacitor (ASC) assembled with PANI/NiCo-LDH as a positive electrode and activated carb...
Journal of Materials Science: Materials in Electronics, 2017
Reduced graphene oxide (RGO) hydrogel films possess a low specific capacitance and have 2 no flex... more Reduced graphene oxide (RGO) hydrogel films possess a low specific capacitance and have 2 no flexible current collectors, which limit their use in flexible supercapacitors. To solve these problems, a novel polyaniline (PANI) modified RGO hydrogel film with an attached graphite 4 current collector (PANI/RGO/G) was prepared. Based on this film, a flexible supercapacitor 5 device was fabricated and characterized. PANI/RGO/G film demonstrates good flexibility and 6 electron transport. The graphite current collector highly reduces the internal resistance of the 7 device. It shows a high specific capacitance of 478 F g 1 at a current density of 2 mA cm 2 based 8 on the mass of one electrode and a good cycling stability (86.5% retention after 5000 cycles). 9 Moreover, during the fabrication of the device, a modified design was adopted to solve the 10 problem of low extension of PANI/RGO/G hydrogel film. The obtained device also exhibits a 11 good flexibility; its capacitance hardly changes after 500 cycles of bending at an angle of 90 o .
Journal of Energy Chemistry, 2018
Homogeneous core-shell structure stabilizes Mn 4+-doped fluoride red phosphors for high-performan... more Homogeneous core-shell structure stabilizes Mn 4+-doped fluoride red phosphors for high-performance warm-white LEDs SCIENCE CHINA Materials 62, 1934 (2019); High-performance supercapacitor based on MOF derived porous NiCo 2 O 4 nanoparticle SCIENCE CHINA Technological Sciences Electrodeposited NiSe 2 on carbon fiber cloth as a flexible electrode for high-performance supercapacitors
Electromagnetic Materials - Proceedings of the Symposium P (ICMAT 2007), 2007
Procedia Engineering, 2015
The iron oxide nanoparticles have been synthesized by coprecipitation and solvothermal reduction ... more The iron oxide nanoparticles have been synthesized by coprecipitation and solvothermal reduction methods. The particles obtained differ in size, the mean size of particles coprecipitated is of 13nm and the particles, prepared by solvothermal reduction method have a size of 20nm. Both kinds of nanoparticles demonstrate narrow particles sizes distribution. The particles which are prepared by coprecipitation method have narrow particles sizes distribution with mean size diameter of 13nm and the particles, prepared by solvothermal reduction method have a size of 20nm. The X-ray diffraction data analysis revealed that highly crystalline and single-phase magnetite nanoparticles are formed by solvothermal reduction technique, whereas coprecipitation leads to the formation of multi-phase composition of a magnetite (72%) and maghemite (28 %). According to the size of nanoparticles obtained, they are in superparamagnetic state for iron oxides. The saturation magnetization of solvothermal prepared particles is higher than those for coprecipitated due to their higher crystallinity and phase purity. Nevertheless, the glycerol dispersion of particles coprecipitated shows higher SLP values than the dispersion of the particles, synthesized by solvothermal reduction method. The heating efficiency of nanoparticles based dispersions is explained by the particles size effect and properties of carrier medium.
Radio absorbing materials based on polyurethane filled with multicomponent particles of MnZn ferr... more Radio absorbing materials based on polyurethane filled with multicomponent particles of MnZn ferrite coated by polyaniline with different conductivity and morphology were prepared. Complex permittivity and permeability spectra of composites were studied in the frequency range from 1 MHz to 3 GHz. Absorption characteristics of single-layer metal-backed radio absorbers based on the obtained materials are numerically estimated. The possibility of attaining the matching condition and altering the operating frequency range of the absorbers from hundreds MHz up to 2 GHz via variation of polyaniline overlayer properties is demonstrated.
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Papers by Natalia Kazantseva