Elena M. Ivan'kova

Russian Academy of Sciences | RAS · Institute of Macromolecular Compounds

In this work, new composite films were prepared by incorporating the disintegrated bacterial cellulose (BCd) nanofibers and cerium oxide nanoparticles into chitosan (CS) matrices. The influence of the amount of nanofillers on the structure and properties of the polymer composites and the specific features of the intermolecular interactions in the m...

Nowadays, a solvent-free method for production of high performance fibers directly from ultrahigh-molecular-weight polyethylene (UHMWPE) reactor powder is being actively developed. It causes the interest in the morphology of the reactor particles and their behavior in thermal and mechanical fields. Changes in the phase composition in virgin particl...

С целью создания тканеинженерного сосудистого имплантата получена биорезорбируемая трубчатая матрица из поли(L-лактида) и разработан метод посева и культивирования на ней мезенхимных стромальных клеток. В группе 1 крысам в брюшную аорту имплантировали матрицы без клеточного материала; в группе 2 – матрицы с предварительно культивированными мезенхим...

Polymeric nanocomposite materials have great potential in the development of tissue-engineered scaffolds because they affect the structure and properties of polymeric materials and regulate cell proliferation and differentiation. In this work, cerium oxide nanoparticles (CeONPs) were incorporated into a chitosan (CS) film to improve the proliferati...

A new biocompatible nanocomposite film material for cell engineering and other biomedical applications has been prepared. It is based on the composition of natural polysaccharides filled with cerium oxide nanoparticles (CeONPs). The preparative procedure consists of successive impregnations of pressed bacterial cellulose (BC) with a sodium alginate...

One of the main research work in the field of polymeric materials was, is and always will be the improvement of their mechanical properties. Comprehensive structural studies of UHMWPE reactor powder, the features of its dissolution and the formation of a gel-state, as well as UHMWPE films oriented up to various draw ratios, were carried out using s...

Chitosan and composite fibers containing chitin nanofibrils have been developed for use in cosmetology. The tensile strength of the chitosan multifilaments is 160.6 ± 19.0 MPa, and of the composite multifilaments containing chitin, nanofibrils are 198.0 ± 18.4 MPa. Chitin nanofibrils introduced into the chitosan solution contribute to the creation...

The surgical reconstruction of blood vessels, including the use of prostheses based on polymeric materials, is one of the main methods of treating cardiovascular pathology; the development of clinically acceptable small-diameter prosthesis is underway. Prostheses of blood vessels with a diameter of 1.2 mm were obtained in this study by electrospinn...

A series of multiblock polyurethane-ureas (PUU) based on polycaprolactone diol (PCL) with a molecular mass of 530 or 2000 g/mol, as well as hard segments of different lengths and structures, were synthesized by the step-growth polymerization method. The chemical structure of the synthesized multiblock copolymers was confirmed by IR- and NMR-spectro...

Одним из основных методов лечения сердечно-сосудистой патологии является хирургическая реконструкция сосудов, в том числе с использованием протезов на основе полимерных материалов; ведется разработка клинически приемлемого протеза малого диаметра. В данной работе протезы кровеносных сосудов диаметром 1.2 мм были получены методом электроформования и...

Samples of composite materials based on high-performance semicrystalline polyimide R-BAPB (based on the dianhydride R: 1,3-bis-(3′,4,-dicarboxyphenoxy)benzene and diamine BAPB: 4,4′-bis-(4″-aminophenoxy)diphenyl)) filled with carbon nanofibers and micron-sized discrete carbon fibers were obtained by FFF printing for the first time. The viscosity of...

Biocompatible electrically conducting chitosan-based films filled with single-wall carbon nanotubes were obtained. Atomic force microscopic studies of the free surface topography revealed a change in the morphology of chitosan films filled with single-wall carbon nanotubes. Introducing 0.5 wt.% of single-wall carbon nanotubes into chitosan results...

HDPE-based composite fibers filled by original and annealed carbon nanodiscs (oND and aND, respectively) were prepared by melt extrusion technology with high-temperature orientational drawing up to draw ratio DR = 8. The thermal properties of the obtained fibers were investigated by DSC and TGA methods. It was shown that the nanofillers can be infl...

In this work, an electrically conductive composite based on thermoplastic polyimide and graphene was obtained and used as a bioelectrode for electrical stimulation of human dermal fibroblasts. The values of the electrical conductivity of the obtained composite films varied from 10-15 to 102 S/m with increasing graphene content (from 0 to 5.0 wt.%)....

A series of polyimide/metal oxide (either ZrO2 or TiO2) nanocomposite films were fabricated based on two polymer matrices. The prepared films were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), and X-ray diffraction analysis (XRD), and their thermal and mechanical properties were investigated with the use of the...

High‐performance fibers have been obtained on the basis of fusible semicrystalline R‐BAPB polyimide (PI) matrix and single‐wall carbon nanotubes by the melt spinning method. The resulting fibers have been subjected to orientational drawing and crystallization annealing. An effect of introducing the single‐wall carbon nanotubes as well as orientatio...

HDPE-based nanocomposite fibers have been extruded from a melt and drawn up to draw ratio DR = 8. Two kinds of carbon nanodiscs (original ones and those exposed to additional annealing) have been used as fillers. Obtained nanocomposite fibers have been investigated with the help of different experimental methods: rheology, SEM and WAXS. It has been...

A polyamic acid (PAA) based on 4,4′-bis(4-aminophenoxy)diphenyldiamine and 1,3-bis-(3′,4-dicarboxyphenoxy)benzene dianhydride was synthesized. PAA fibers were prepared by wet spinning. Subsequent cyclization of PAA units was achieved using chemical or thermal imidization. The influence of the imidization method and process conditions on the chemica...

Reactor particles of nascent polyetherimid (PI) R-BAPB powder consist of numerous morphological units of the lamellar type, which have semicrystalline structure. Two endo-peaks at 318 °C and 340 °C were observed in the DSC thermogram of the PI powder. A unique in-situ thermo-WAXS experiment showed no significant difference in X-ray peak profiles wh...

Thermoplastic semi-crystalline polyimides R-BAPB in the powder form were synthesized on the basis of dianhydride R (1,3-bis-(3,3′,4,4′-dicarboxyphenoxy)benzene) and diamine BAPB (4,4′-bis(4″-aminophenoxy) biphenyl) with carbon nanoparticles. The fibers based on R-BAPB modified with carbon nanoparticles were processed by melt technology. The effect...

The influence of ultrasonic treatment parameters of chitin nanofibrils aqueous suspension on structure, strength and deformation properties of chitosan-based composite films and fibers was investigated. Model calculations of ultrasound-induced cavitation parameters in the aqueous suspension of the chitin nanofibrils showed that an increase in the f...

A correlation was established between, on the one hand, the values of the molecular weight of UHMWPE synthesized using postmetallocene bis-phenoxyimine catalysts and the bulk density of synthesized nascent reactor powders of UHMWPE, and, on the other hand, the values of the elastic modulus, breaking strength and breaking elongation of oriented tape...

Using the methods of X-ray diffraction and scanning electronmicroscopy, the structure of composite films based on chitosan andsingle-wall carbon tubes has been studied. It is shown that theintroduction of carbon nanotubes leads to the ordering of the chitosanstructure. Increase in concentration of nanotubes (from 0 to 3%) causesrise in the value of...

A method for calculating the size distribution of nanocrystalline elements of the polymer structure is proposed. The longitudinal size distribution (thickness) of ultrahigh molecular weight polyethylene lamellae was calculated from calorimetric data. The results of calculating the maximum values of the distribution are consistent with the known dat...

The fibers based on thermoplastic partially crystalline polyetherimide R-BAPB modified by vapor grown carbon nanofibers (VGCF) were prepared by melt extrusion, exposed to orientational drawing, and crystallized. All of the samples were examined by scanning electron microscopy, X-ray scattering, and differential scanning calorimetry to study how the...

A comparative study of molecular dynamics in near-surface nanolayers and in a bulk of polyethylene is presented. Molecular mobility in near-surface nanolayers of polyethylene reactor powders and melt-crystallized films of various molecular weights prepared in different crystallization conditions were studied with the help of thermoluminescence tech...

The ultra-high-molecular-weight polyethylene reactor powders are widely used for the actively developing solvent-free method for producing high-strength high-modulus PE filaments, which includes the compaction and sintering of a powder followed by orientational hardening. To find an appropriate regime of the technological process, it is important t...

In this work, composite mono- and multifilament yarns of polylactide (PLA) containing 1 wt.% of commercial Poviargol (silver nanoparticles stabilized with poly(vinylpyrrolidone)) were prepared. The results of scanning electron microscopy revealed that filler particles are uniformly distributed inside PLA yarns, irrespective of sample type. It was a...

In the present work, fibers based on heat-resistant amorphous polyimide brand Ultem-1000 were prepared by melt extrusion. Vapor-grown carbon nanofibers (VGCFs) and single-wall carbon nanotubes (SWCNTs) were used to increase the mechanical characteristics of the polymer fibers. The fibers were characterized by scanning electron microscopy (SEM), the...

Background.Local prevention of periprosthetic infection and treatment of infectious complications after various joints arthroplasties includes the use of polymethylmethacrylate-based spacers impregnated with antimicrobial agents. At the same time, the added components are able to change the bone cement characteristics and have variable antimicrobia...

A technique for the fabrication of bacterial cellulose-based films with CeO2 nanofiller has been developed. The structural and morphological characteristics of the materials have been studied, their thermal and mechanical properties in dry and swollen states having been determined. The preparation methodology makes it possible to obtain composites...

A technique for fabrication of bacterial cellulose-based films with CeO2 nanofiller has been developed. The structural and morphological characteristics of the materials have been studied, their thermal and mechanical properties in dry and swollen states having been determined. The preparation methodology makes it possible to obtain composites with...

A technique for fabrication of bacterial cellulose-based films with CeO2 nanofiller has been developed. The structural and morphological characteristics of the materials have been studied, their thermal and mechanical properties in dry and swollen states having been determined. The preparation methodology makes it possible to obtain composites with...

The scale of magnetic correlations in materials based on reduced graphene oxide (RGO) has been estimated for the first time using the method of small-angle scattering of polarized neutrons. This information cannot be obtained by other methods. Experiments have demonstrated the presence of small-angle magnetic-nuclear interference scattering for bot...

A technique of fabrication of bacterial cellulose-based films with CeO2 nanofiller has been developed. The structural and morphological characteristics of the materials have been studied, their thermal and mechanical properties in dry and swollen states having been determined. The preparation methodology gives way to obtaining composites with the u...

Using a twin-screw microextruder, fibers based on polylactide and vapor grown carbon nanofibers (VGCF) with orientational stretching by 4 and 6 times were obtained. It was shown that VGCF doesn't influence on thermal properties of composite fibers based on PLA. Also, evenly dispersion of VGCF in PLA matrix was observed using by SEM. The electricall...

Chitosan fibers were prepared by coagulation from 4% chitosan solutions in 2% acetic acid solution. The synthesis method for polypyrrole (PPy) involving in situ oxidative polymerization of gaseous pyrrole on the surface of chitosan fibers was developed. Structure of the composites was studied by scanning electron microscopy. Electrical conductivity...

In this study, bioactive composite systems based on natural polymers (chitosan and lignin) were prepared in this study. The structural, mechanical, and morphological properties of chitosan-based materials containing various amounts of lignin filler were investigated. The infra-red IR spectroscopy data confirmed the formation of chemical bonds betwe...

The paper is devoted to the study of influence of chitin nanofibrils on the structure, surface morphology, mechanical properties, and electrical conductivity of chitosan-based composite films intended for use in biomedical technologies. It was demonstrated that the optimal concentration of chitin nanofibrils in the composite film is 5 wt.%. For the...

Structural features of films and fibers obtained from mixtures of a chitosan solution in acetic acid with an ethanol and NaOH solution were investigated. Phase separation in the system that included chitosan, acetic acid, ethanol, NaOH and water was studied using scanning electron microscopy and time dependence of optical density. Optical densities...

Composite fibers based on a polylactide (PLA) matrix with the addition of dispersed spherical particles, namely chitin nanoparticles modified with polyethylene glygol (PEG) and silver nanoparticles modified with polyvinylpyrrolidone, have been obtained using a twin-screw microextruder. The resulting fibers were subjected to high-temperature orienta...

С использованием двухшнекового микроэкструдера получены композиционные волокна на основе полилактидной (ПЛА) матрицы с добавлением дисперсных сферических частиц: наночастиц хитина, модифицированных полиэтиленглиголем (ПЭГ), и наночастиц серебра, модифицированных поливинилпирролидоном. Полученные волокна подвергали высокотемпературной ориентационной...

Relevance. Currently, all over the world, during cataract surgeries, a huge number of intraocular lenses (IOLs) made of different materials are implanted. Alongside with the development of modern IOL materials and designs, publications about their opacities appear. The nature and the localization of IOL opacities mainly depend on the properties of...

In the process of this work, an oligoimide FT-BAPB-R-BAPB-FT was synthesized, the particles of which consist of numerous lamellas having a semi-crystalline structure. On the DSC thermogram of oligoimide powder, two endo peaks were observed at 281.1°C and 306.4°C. A unique WAXS experiment was performed in-situ by heating the reactor oligoimid powder...

The homologous series of thermoplastic polyetherimide based on resorcinol dianhydride R (1,3-bis-(3,3’,4,4’-dicarboxyphenoxy)benzene) and tetranuclear diamine BAPB (4,4’-bis(4”-aminophenoxy) biphenyl) (R-BAPB) were synthesized in powder form. Fibers were obtained by melt spinning of this polyimide. It was analyzed, how changes in the molecular weig...

In this work, the two-stage process for producing polyimide fiber from polyamic acid (PAA) by wet spinning was used. Polyimide fibers were obtained by thermal and chemical imidization. The effect of the imidization method (chemical and thermal) on morphology, chemical structure, thermal stability and mechanical properties of polyimide fibers was in...

Using a twin-screw microextruder, fibers based on polylactide and carbon nanofibers (CNFs) were obtained with 4-and 6-fold orientational stretching. The electroconductive and deformation-strength properties of composite fibers were investigated depending on the concentration of the filler and orientational stretch ratio of the polymer. It is shown...

The paper presents a comprehensive analysis of the elastic properties of polystyrene-based nanocomposites filled with different types of inclusions: small spherical particles (SiO2 and Al2O3), alumosilicates (montmorillonite, halloysite natural tubules and mica), and carbon nanofillers (carbon black and multi-walled carbon nanotubes). Block samples...

The influence of nanosized cerium oxide as an active filler on the mechanical properties and thermal stability indices and heat resistance of films of thermally stable aromatic polyimides of various chemical structures is studied. It is shown that, depending on the polyimide structure the introduction of cerium oxide nanoparticles into the film can...

We have demonstrated the possibility of application of electroconducting polymers for fabricating bioactive matrices for tissue engineering. Polypyrrole is most promising among such polymers in the context of its biomedical applications. Polypyrrole possesses a number of properties that make it an adequate basis for preparing “smart” bioactive mate...

A polyamide acid (PAA) based on diamine 4,4'-bis (4-aminophenoxy) diphenyl and 1,3-bis (3',4-dicarboxyphenoxy) benzene dianhydride was synthesized. PAA fibers were obtained by wet spinning. Then, these fibers were converted into polyimide by thermal imidization. Dependence of the structure and properties of fibers on the die drawing and the composi...

To design novel polymer materials with optimal properties relevant to industrial usage, it would seem logical to modify polymers with reportedly good functionality, such as polyimides (PIs). We have created a set of PI-based nanocomposites containing binary blends of CeO2 with carbon nanoparticles (nanocones/discs or nanofibres), to improve a numbe...

Abstract—Using X-ray diffraction, electron microscopy, and differential scanning calorimetry, the structure and mechanical properties of tubes based on poly (L-lactide) microfibers obtained by electrospinning from a dichloroethane solution and designed for implantation in small diameter blood vessels during prosthetics are studied. It is shown that...

Abstract—Nanomodified polyetherimide samples obtained by fused deposition modeling using an experimental setup for three-dimensional printing of highly heat-resistant plastics are studied. Their structure and thermal properties are investigated by pycnometry, scanning electron microscopy, differential scanning calorimetry, thermogravimetry, and dil...

Abstract—Nonwoven tubular bioresorbable matrices with an inner diameter of 1.1 mm were obtained by electroforming from solutions of poly (L-lactide) (PLA). Matrices were implanted into the abdominal aorta of rats as a tissue-engineering vascular implant for a period of 2 days to 16 months and showed high biocompatibility, nontoxicity, and pronounce...

The synthesis of new forms of hydroxyapatite (HA) and the study of their interaction with living cells are a promising area of modern nanotechnology in chemistry and cell biology. A comparative analysis of the interaction between HA nanoparticles of various origin with living cells is carried out. Scanning electron microscopy revealed that native H...

Interaction between water and composite films based on chitosan and chitin nanofibrils was studied. Isotherms of water vapor sorption by composite films were used to calculate partial values of entropy and enthalpy of sorbate; dependences of entropy and enthalpy on water sorption value were obtained. It was demonstrated that introducing chitin nano...