A.S. Kochetkova
Language of the thesis
Thesis name in original language
Abstract & Cover

NOTES: full Russian thesis available on “Link to external PDF”. English + Russian summary available here by clicking the title or “Read Thesis” link. 

1. Systematic studies using AFM were carried out for the first time surfaces of polymeric (LDPE, PVC films filled with Al nanoparticles2O3) and inorganic silicate matrices of various geometric shapes (glass microspheres, quartz fibers, plates of borosilicate and quartz glass) at different stages of the formation of element oxide compositions of various compositions and structures on them during the MN process, associated with the previously identified structural and size effects in the products obtained the specified method. eighteen 2. Proposed methodological approaches to the study by the AFM method materials of various geometric shapes and developed methods for calculating the effective diffusion coefficient of water vapor in PVC films containing 2 wt. % nanodispersed Al2O3, qualitative assessment of adhesion to the substrate surface of nanosized coatings, based on a combination of contact and semi-contact AFM modes, and calculation of the pressure in the “probe-sample” contact zone. 3. It has been established that the process of MN of titanium oxide nanocoatings on the surface hollow soda borosilicate glass microspheres using TiClfour accompanied by side reactions with the formation of NaCl crystals and TiO particles2. 4. Using AFM, differences were established in the formation by the method MN and the occurrence of recrystallization processes during the subsequent heat treatment (900°С) of the aluminum oxide nanocoating (after 400 cycles of treatment with Al(CH3)3and H2O) on the surface of optical fibers and quartz plates. It is shown that coatings on a flat surface crack when heated, but without a significant change in the size of aluminum oxide structures (size 40–50 nm), and large crystallites (up to lateral sizes of 200–210 nm) form on fibers during recrystallization without disturbing the continuity of the coating. 5. The AFM method was used to study the change in the morphology of titanium oxide coating formed on the surface of borosilicate glass by conducting 25, 50, 100, 200 and 300 MN cycles, and studied the effect of simultaneous exposure to heat treatment at 480°C and X-rays (irradiation dose of 10-3C/kg (~ 4 R)) in vacuum (10-3 Pa) on the structure and properties of titanium oxide coatings of various thicknesses (100, 200 and 300 MN cycles) formed on the inner surface of the glass cases of X-ray tubes. It is shown that the combined action of temperature and Xray radiation in vacuum intensifies the recrystallization process in the titanium oxide layer, with the smallest transformations occurring in the composition of the coating formed as a result of 300 cycles of glass treatment with TiCl vapor.fourand H2Oh 6. On the surface of high-pressure polyethylene (LDPE) films by processing in a different specified sequence with pairs of titanium, phosphorus and water chlorides, two-component nanostructures with different mutual arrangement of phosphorus and titanium oxide groups were synthesized. According to the AFM data, it was found that during the modification of LDPE films, the change in the polymer surface morphology is significantly affected by the sequence in which reagents are fed into the reaction chamber. The strongest amorphization of the LDPE surface occurs during the formation of phosphorus- and phosphorus-titanium oxide groups, in comparison with the polymer film samples, where TiCl was used in the first MT cycle.four. At the same time, according to the RMSCA data, the concentration of phosphorus in such samples significantly exceeds the concentration of titanium (0.22 and 0.01 mmol/g, respectively). 7. It has been established that two-component energy traps in the form of titanium phosphorus oxide and phosphorus-titanium oxide surface nanostructures provide, in comparison with single-component compositions, an increase in the thermal stability of the surface potential of electrets made on their basis. The residual potential of the electret, with a value of 100 - 150 V, is maintained up to 19 temperature of the beginning of melting of the polymer film (200ºС). A mechanism is proposed for the effect of physically sorbed water on the electret properties of modified HDPE films, which is based on the redistribution of electron density in the COPO-Ti-OH chain. 8. Using AFM data, an assessment of the effectiveness of hydrophobization of an LDPE film with phosphorus oxide centers subjected to additional treatment with Si(CH3)2Cl2. A regular increase in the size of structures corresponding to hydrated regions of the polymer surface containing grafted functional groups was revealed. List of major papers published on the topic of the dissertation Articles: 1. Kochetkova A.S. Study of nanocomposites based on polyvinyl chloride using atomic force microscopy / A.S. Kochetkova, N.Yu. Efimov, E.A. Sosnov // Scientific and technical. Bulletin of St. Petersburg State Polytechnical University, Fiz.-Mat. sciences.- 2013.- № 1 (165).- p.114-119. 2. Kochetkova A.S. Influence of chemical modification of the filler surface on the structure and permeability of a composite film based on polyvinyl chloride / A.S. Kochetkova, N.Yu. Efimov, E.A. Sosnov, A.A. Malygin // Zhurn. appl. Chemistry. - 2015. - T.88, No. 1. - P.116-124. 3. Kochetkova, A.S. Evaluation of the wear resistance of the surface of modified PVC films using scanning probe microscopy /A.S. Kochetkova, P.N. Gorbushin, E.A. Sosnov, K. Kolert, A.A. Malygin // Deformation and destruction of materials. - 2016. - No. 8. - P.36 - 43. 4. Malygin, A.A. Synthesis by molecular layering and functional properties of metal oxide nanocoatings on the surface of quartz optical fibers / A.A. Malygin, V.V. Antipov, A.S. Kochetkova, G.Ya. Buimistryuk // Zhurn. appl. chemistry. - 2018. - V.91, No. 1. - P.17-27 

Source of Information
Anatoly Malygin
Petersburg State Institute of Technology (Technical University)
(Saint Petersburg, Russia)
Other notes
Supervisor: Malygin A.A. Scientific consultant: Sosnov E.A.
External Link
Read Thesis
linkedin invite