Anastasia V Bolshakova

• PhD
• Senior Researcher at Lomonosov Moscow State University

A study was made of the conditions of producing micron-sized reliefs by thermally stimulated shrinkage of metallized commercial biaxially oriented polypropylene films. It was shown that, in annealing within a temperature range close to the polypropylene melting point, the film shrinks in two directions to form folded structures on the surface. The...

The radical polymerization of n-butyl acrylate in organic, aqueous, and water–alcohol media in the presence of poly(acrylic acid) containing a trithiocarbonate group within the chain is studied for the first time. It is shown that in nonselective solvents (1,4-dioxane and DMF) poly(acrylic acid) serves as a reversible addition–fragmentation chain-t...

Amorphous polyethylene terephthalate was oriented via rolling on a laboratory mill under room conditions. The influence of rolling on the polymer structure was investigated. The plastic deformation of the polymer was inhomogeneous at the initial stages of rolling. The deformation was localized in a system of almost perpendicular shear bands forming...

Amorphous polyethylene terephthalate (PET) were oriented by rolling on a laboratory�scale rolling press under ambient conditions. The effect of rolling on the polymer structure was studied. At early stages of rolling, plastic deformation of the polymer is inhomo�geneous. Deformation is localized in the system of nearly perpendicular shear bands for...

Results of studies aimed at developing a new approach to measuring stress-strain properties of nanosized solids (strength, yield stress, and the value of plastic deformation at uniaxial tension) are generalized. This approach is based on the analysis of the parameters of microrelief arising upon the deformation of polymer films with thin coatings....

The features of surface structuring during tensile drawing of PET films with deposited nanothick coatings are studied. In contrast to our earlier studies, this investigation is focused on the study of nonmetallic coatings (carbon deposited by vacuum sputtering and modified silica deposited via evaporation from the solution). In both cases, the tens...

Data on the strength of coatings based on noble metals (Pt, Au) deposited onto PET films by the method of ionic plasma sputtering are analyzed. In addition to precipitation of the metal, this mode of deposition is accompanied by modification of the surface polymer layer due to its interaction with plasma. As a result, a complex three-layered struct...

Data on the strength of coatings based on noble metals (Pt, Au) deposited onto PET films by the method of ionic plasma sputtering are analyzed. In addition to precipitation of the metal, this mode of dep osition is accompanied by modification of the surface polymer layer due to its interaction with plasma. As a result, a complex threelayered struct...

The results of investigation using new method for evaluation of stress-strain properties solids (strength, ductility) are described. The method is based on the analysis of microrelief parameters, which is occurred upon the uniaxial stretching of polymer films with rigid thin coating. For the first time, it is shown that the strength and ductility o...

An electron-microscopic study of the formation of thin metal coatings (gold and aluminum) on a PET film is performed. During the deposition of gold coatings, a well-pronounced interfacial polymer/metal layer is formed, while, in the case of aluminum coatings, the polymer/metal interface is well-defined. The assumption is made that this effect is ca...

The surface of several plasma-treated polymers after their tensile drawing is examined by microscopic study. This process is accompanied by the development of a surface micropattern that is characteristic of the rigid coating on a soft substratum system. The modified surface layer forms even during short-time plasma treatment (less than one minute)...

The surface treatment of poly(ethylene terephthalate) (PET) and poly(vinyl chloride) (PVC) films in cold plasma over 1–15 min was carried out. It was found that the subsequent deformation of the films is accompanied by a special type of surface structuring that has been previously observed for polymer films with a thin hard coating. It was shown th...

The most complicated problem in microbiology is to study microorganisms in the native environment. Native biotopes (soils etc.) are complex mixture of many environments that are very heterogenic and have different physicochemical, mineralogical and other properties. Microorganisms form and change the environmental during their life, as well as the...

A microscopic investigation of the structural features of polyethylenetherephthalate (PET) films with thin golden layers deposited by the ion-plasma method has been carried out. It is shown that a continuous metallic layer does not arise on a polymer surface under an effective thickness of metallic coating of 5–7 nm or less. In this case the metal...

The structures of thin films of the polystyrene-polybutadiene-polystyrene (SBS) and polystyrene-poly(methyl acrylate)-polystyrene (SMAS) triblock copolymers were studied. The film morphology was found to depend on the conditions of film formation. The average domain sizes of these films and the period of the lamellar structure of SMAS films were de...

Structural rearrangements taking place upon the annealing of solvent-crazed isotactic PP are studied by the direct microscopic method. Independently of the type of its crystalline structure, solvent-crazed PP undergoes shrinkage in a wide temperature interval, starting even from room temperature and up to its melting temperature. This shrinkage is...

The structure of thin films of the polysterene-polymethylacrylate-polysterene triblock copolymer was studied. Universal algorithms to analyze atomic-force-microscopy images of thin block-copolymer films were developed.

The structures of thin films of the polystyrene-polymethacrylate-polystyrene (SMAS) triblock copolymer were studied. A versatile algorithm for analysis of the AFM images of thin block-copolymer films was developed.

Structural rearrangements during the temperature-induced shrinkage of amorphous polycarbonate after its tensile drawing below and above the glass transition temperature, rolling at room temperature, and solvent crazing have been studied with the use of the direct microscopic procedure. This evidence demonstrates that the character of structural rea...

A direct microscopic procedure is used for studying structural rearrangements during the annealing of PET samples after solvent crazing. Even at room temperature, solvent-crazed PET samples experience shrinkage which is provided by processes taking place in crazes. This shrinkage is observed at temperatures up to the glass transition temperature of...

Structure of surface layer of polymer sample with a thin metallic coating after uniaxial drawing of glassy PET is studied. The dependences of the dimensions of fractured fragments on the conditions of deformation are established. Fracture of the coating during tensile drawing of PET is shown to take place in the region of forming neck, and the mech...

A new microscopic procedure for the visualization of structural rearrangements in amorphous polymers during their deformation to high strains is described. This approach involves the deposition of thin (several nanometers) metallic coatings onto the surface of the deformed polymer. Subsequent deformation entails the formation of a relief in the dep...

The plane shrinkage of various elastomers [natural rubber, synthetic isoprene rubber, and plasticized poly(vinyl chloride)] at room temperature has been studied via direct microscopic observations. Prior to deformation, the surface of polymer samples is decorated with a thin (several nanometers) metallic layer. Further deformation leads to formatio...

The mechanism of fracture is studied for a thin metallic (platinum, gold) coating deposited onto the surface of glassy poly(ethylene terephthalate) that is subjected to uniaxial stretching. The structure of the surface layer in the deformed polymer and the size distribution of the fragments produced by fracture are analyzed. Fragmentation of the co...

A direct microscopic observation procedure is applied to study the deformation of amorphous PET decorated with a thin metal layer when stretching is performed at different draw rates and at temperatures below and above the glass transition temperature T g. Analysis of the formed microrelief allows stress fields responsible for the deformation of t...

The uniaxial tensile drawing of films based on a glassy PET with a thin metallic coating (platinum, aluminum) is accompanied by disintegration of the coating into individual fragments shaped as asymmetrical ribbons; the formed ribbons are primarily oriented perpendicular to the direction of tensile drawing. As a result, the polymer surface layer ac...

The process of the enlargement of gold hydrosol nanoparticles adsorbed on the surfaces of glassy polymers (polystyrene and poly(2-vinylpyridine)) in mixed aqueous solution of chloroauric acid and hydroxylamine is studied. It is established that the character of this process depends on the intensity of metal-polymer interaction and the density of na...

This paper is dedicated to atomic force microscopy (AFM) as a progressive tool for imaging bacterial surfaces and probing their properties. The description of the technique is complemented by the explanation of the method's artifacts typical, in particular, for the imaging of bacterial cells. Sample preparation techniques are summarized in a separa...

An instrumental technique is proposed for the determination of two-dimensional maps of the local Young modulus and the adhesion force of a polymer surface using atomic force microscopy. Data on the surface characteristics of a nanostructured polymer, the styrene-butadiene-styrene triblock copolymer, are presented. Problems concerning the calibratio...

A direct microscopic procedure was used tor studying the mechanism of deformation of rubbery polymers. To visualize structural rearrangements in the deformed polymer, it is sufficient to decorate its surface with a thin rigid coating prior to deformation. As a result of deformation and related changes in the surface area of the test polymer sample,...

A special procedure for studying structural rearrangements in polymers under their uniaxial compression was proposed. A cylindrical polymer sample commonly used in deformation tests was composed of thin polymer layers. After deformation, this sample was disassembled into individual layers, and their structure and properties were examined (the struc...

A special procedure for studying structural rearrangements in polymers under their uniaxial compression was proposed. A cylindrical polymer sample commonly used in deformation tests was composed of thin polymer layers. After deformation, this sample was disassembled into individual layers, and their structure and properties were examined (the struc...

A direct microscopic procedure was used for studying the mechanism of deformation of rubbery polymers. To visualize structural rearrangements in the deformed polymer, it is sufficient to decorate its surface with a thin rigid coating prior to deformation. As a result of deformation and related changes in the surface area of the test polymer sample,...

In this work scanning probe microscopy techniques were applied for indication and morphology study of bacteria in native soil, permafrost, ground water and ices samples. Wide variety of atomic force microscopy modes might help in this complicated task, namely: force curve mapping, measuring adhesion properties, study in liquid experiments as well a...

A new approach to SPM studies over Internet is discussed. The supposed configuration of Internet-based laboratory is presented. Some parts of this laboratory are already implemented by Advanced Technologies Center at the Department of Chemistry of Moscow State University. The results of this implementation are discussed.

Antarctic permafrost, ground ices and ice sheet are the best natural models for development of methodologies for conducting astrobiological research relevant to the study of icy bodies of the Solar System and in particular of Mars. The method employed in this research is the in-situ investigation (SEM, AFM, epifluorescence microscopy, lipid biomark...

Escherichia coli bacterial cells of two strains JM109 and K12 J62 were imaged with atomic force microscopy (AFM) in different environmental conditions. The AFM results show that the two strains have considerable difference in the surface morphology. At the same time after rehydration both strains show the loss of the topographic features and increa...

The problems associated with the possibilities of scanning probe microscopy for the study of soil bacteria Arthrobacter globoformis was discussed in the article. The elastic properties of the bacterial cell wall in different stages of their life cycle were investigated by atomic force microscopy. It was found that the rigidity of cell wall of the v...

Adsorption of the poliomyelitis virus on various substrates has been studied by scanning tunnelling and atomic force microscopies. Virus particles have been immobilized on the surface of different substrates: freshly cleaved mica, high-orientation pyrolytic graphite, gold and silver films, palladium and gold alloy (50/50), titanium oxide, and mica...