A new approach for fabrication of photochromic composite structures based on hydrated tungsten (VI) oxide particles
in cellulose matrix
P. F. Prokopovich, E. S. Kirillova, V. A. Gurtov
Photochromes have promising applications in the field of optoelectronics. At the present time there are a lot of photochromic systems, but most coating techniques show low manufacturability caused by the technical challenge in thin layers fabrication and scaling up to industrial size. The present investigation deals with hitherto unreported synthesis and characterization of a photochromic composite consisting of hydrated tungsten (VI) oxide ultradispersions in a cellulose-based matrix. The composite is obtained from solution of cellulose in cuprammonium with addition of a tungstate-ion containing chemical agent (sodium tungstate dihydrate) by means of cellulose and tungstic acid regeneration in an acid medium. Composite coatings are obtained by screen printing process. Structure and phase composition of precipitates were established. In addition, photochromic properties, including spectral dependences of the reflection coefficient of bleached and colored states, kinetics of photochromic transformations, and the dependence of coloration efficiency from the wavelength of radiation, were investigated. Furthermore, a number of ways to interpret obtained results were proposed on the strength of possible mechanisms of photochromic effect reflecting the distinguishing features of the composite material.
Keywords: cellulose-based matrix, transition metal oxides, tungstic acid, hydrogen tungsten bronze, photochromism.
DOI: 10.30791/1028-978X-2019-3-5-18
Prokopovich Pavel — Institute of Geology, Karelian Research Centre of Russian Academy of Sciences (Petrozavodsk, 185035, ul. Pushkinskaya, 11), leading physicist in analytical centre, specialist in the field of physics and chemistry of polymers, composites and polymer materials. E-mail: proxy88@petrsu.ru.
Kirillova Ekaterina — Department of Solid State Physics, Petrozavodsk State University (Petrozavodsk, 185014, ul. Universitetskaya, 10), engineer, specialist in the field of physicochemical technologies. E-mail: little.lf.foot@gmail.com.
Gurtov Valery — Department of Solid State Physics, Petrozavodsk State University (Petrozavodsk, 185014, ul. Universitetskaya, 10), Dr Sci, professor, head of department, specialist in the field of solid-state electronics. E-mail: vgurt@petrsu.ru.
Reference citing
Prokopovich P. F., Kirillova E. S., Gurtov V. A. Novyj podhod k sozdaniyu fotohromnyh kompozitov na osnove chastic gidratirovannogo oksida vol'frama (VI) i cellyuloznogo svyazuyushchego [A new approach for fabrication of photochromic composite structures based on hydrated tungsten (VI) oxide particles in cellulose matrix]. Perspektivnye Materialy — Advanced Materials (in Russ), 2019, no. 3, pp. 5 – 18. DOI: 10.30791/1028-978X-2019-3-5-18
Effect of micro-impurities on the electronic structure
and emission properties of the microwave devices
cathode materials
V. I. Kapustin, I. P. Li, A. V. Shumanov, S. O. Moskalenko, V. I. Svitov
The emission properties of all cathodes types in electrovacuum devices are determined by barium oxide crystallites formed with cathode activation. It results from thermal decomposition of barium-calcium-strontium triple carbonate in nickel oxide cathodes, of barium-calcium aluminate in metal-porous cathodes or from interaction of barium in Pd5Ba phase with dissolved oxygen in palladium-barium cathodes during their heating in vacuum. The material of the metal matrix is in the process a catalyst for the initial carbonate or aluminate decomposition in corresponding types of cathodes, as well as a supplier of dissolved oxygen in palladium-barium cathodes during the formation of barium oxide crystallites. It was previously found that oxygen vacancies play a decisive role in the formation of barium oxide crystallites emission properties, while the possible role of micro-impurities in barium oxide crystallites was not considered. The methods of optical and electronic spectroscopy were used first for systematic studies of the effect of micro-impurities on the electronic structure of barium oxide. It is established that certain types of trace impurities, such as nickel, scandium and combined calcium with strontium, regularize oxygen vacancies in barium oxide crystallites, which directly influences the diffusion processes of oxygen in such crystallites. Thus some types of micro-impurities (nickel, scandium) form additional surface states near the edge of the valence band decreasing electron work function of the cathode material.
Keywords: microwave devices cathodes, cathode materials, micro-impurities in materials, emission properties.
DOI: 10.30791/1028-978X-2019-3-19-29
Kapustin Vladimir — JSC “Pluton” (105120, Moscow, ul. Nizhnyaya Syromyatnicheskaya, 11); Technical center “Basic technologies of electro-vacuum devices” of the Russian Technological University MIREA (119434, Moscow, Prospect Vernadskogo, 78), Dr.Sci. (Phys-Math), professor, leading specialist, head of Nanoelectronics department, specialist in physical electronics, surface physics, materials and technologies of electronics. E-mail: kapustin@mirea.ru.
Li Illarion Pavlovich — JSC “Pluton” (105120, Moscow, ul. Nizhnyaya Syromyatnicheskaya, 11), PhD (Eng), director of technical center “Basic technologies of EVD”, scientific interests: electronic devices, materials and technology of electronics. E-mail: i.li@pluton.msk.ru.
Shumanov Alexey — JSC “Pluton” (105120, Moscow, ul. Nizhnyaya Syromyatnicheskaya, 11); Russian Technological University MIREA (119434, Moscow, Prospect Vernadskogo, 78), deputy director of technical center “Basic Technologies of EVD”, post-graduate student of Nanoelectronics department, specialist in the field of preparation of optoelectronic devices and systems, nanotechnology, materials and technology of electronics. E-mail: alexeyshumanov@yandex.ru.
Moskalenko Sergey — JSC “Pluton” (105120, Moscow, ul. Nizhnyaya Syromyatnicheskaya, 11); Russian Technological University MIREA (119434, Moscow, Prospect Vernadskogo, 78), engineer-technologist 1st category of the technical center “Basic technologies of EVD”, bachelor of “Nanotechnologies and microsystem equipment” department, scientific interests: nanotechnology, materials and technology of electronics. E-mail: s.o.mockalenko@gmail.com.
Svitov Vladislav — Russian Technological University MIREA (119434, Moscow, Prospect Vernadskogo, 78), PhD (Chem), professor of Energy processing systems and installations department, scientific interests: surface science, spectroscopy, nano-systems research methods, vacuum-plasma technologies. E-mail: svitov@mirea.ru.
Reference citing
Kapustin V. I., Li I. P., Shumanov A. V., Moskalenko S. O., Svitov V. I. Vliyanie mikroprimesej na ehlektronnuyu strukturu i ehmissionnye svojstva materialov katodov SVCH priborov [Effect of micro-impurities on the electronic structure and emission properties of the microwave devices cathode materials]. Perspektivnye Materialy — Advanced Materials (in Russ), 2019, no. 3, pp. 19 – 29. DOI: 10.30791/1028-978X-2019-3-19-29
Thermo-sensitive hydrogels on the basis of primary copper
and acrylamide copolymers
S. Z. Zeynalova, L. A. Smirnova, A. V. Mitin
Water soluble starch was prepared by graft radical polymerization in solution. Likewise, three-dimensional copolymers of starch and acrylamide were obtained by the use of the same method in solution using N’N-methylene-bis-acrylamide crosslinking agent. The novelty of developed method consists in that hydrogels with the ratio Starch: Acrylamide by weight 1: 0.5-3 in the composition were obtained without the gelatinization stage of starch. The resulting product is a hydrogel with a high sorption capacity and its maximum swelling degree is 550 times (55,000%) per 1 gram of dry product at 60 c for 1:2+1% in content. Hydrogels are optically transparent, heat-sensitive, capable of six-fold cycles sorption and desorption of water, decreasing swallowing degree at 30 % from previous value each time. Dehydration proceeds gradually and hydrogels give all amount of swollen water back throughout 6 – 7 days. Hydrogels undergo decomposition under specific starch enzymes as a-amylase and glucoamylase. The density of Starch:Acrylamide: N, N’-methylenebisacrylamide hydrogel by weight 1:2+1% in content is 0.8978 g/cm3, and the degree of crosslinking is 1 crosslink/160 unit of copolymer. Obtained three-dimensional copolymers are promising materials for production of superabsorbents, hydrograins, absorbent hygiene products.
Keywords: starch, modification, acrylamide, hydrogel, thermal sensitivity.
DOI: 10.30791/1028-978X-2019-3-30-38
Zeynalova Sakina — Lobachevsky State University (Nizhny Novgorod, 603950, Gagarin Ave., 23), student of the first course of the master’s degree in chemical faculty. E-mail: sakina3@mail.ru.
Smirnova Larisa — Lobachevsky State University (Nizhny Novgorod, 603950, Gagarin Ave., 23), Dr. Sci. (Chem), professor of the High-molecular compounds and colloid chemistry department. E-mail: smirnova_la@mail.ru.
Mitin Alexander — Lobachevsky State University, Research Institute of Chemistry, University of Nizhny Novgorod (Nizhny Novgorod, 603950, Gagarin Ave., 23), PhD (Chem), head of laboratory of Chromatography, mass spectrometry and elemental analysis. E-mail: ckp@ichem.unn.ru.
Reference citing
Zeynalova S. Z., Smirnova L. A., Mitin A. V. Termochuvstvitel'nye gidrogeli na osnove privityh sopolimerov krahmala i akrilamida [Thermo-sensitive hydrogels on the basis of primary copper and acrylamide copolymers]. Perspektivnye Materialy — Advanced Materials (in Russ), 2019, no. 3, pp. 30 – 38. DOI: 10.30791/1028-978X-2019-3-30-38
Correlation between high-dose radiation-induced swelling
and grain size of 16 Cr – 15 Ni steel
Е. А. Kinev
The aim of this paper is investigation of the correlation between radiation-induced swelling and grain size of different 16 Cr – 15 Ni steel batches. Metallographic techniques to identify austenite grain depending on material state have been used. Dose-swelling relationships of the steel with different grain size have been plotted. In initial state, at damage doses lower than 20 dpa and irradiation temperature below 450 °С, electrolytic etching in nitric acid is preferable. At doses higher than 40 dpa and irradiation temperatures 500 – 650 °С both electrolytic and chemical etching of the austenite boundaries are effective. In the damage dose range 1 – 85 dpa and irradiation temperatures below 650 °С austenite grain size for 16 Cr – 15 Ni steel is rather stable during similar tube processing technique. The grain size can be used as monitor of irradiated steel initial heat treatment. Statistical analysis of the grain structure of irradiated samples showed inverse correlation between the swelling and the grain size. The highest radiation-induced swelling resistance with incubation swelling period 41 dpa and steady-state swelling rate not more than 0,2 %/dpa is typical for steel batches with technological grain size 18 – 30 mkm.
Key words: 16 Cr – 15 Ni steel, neutron irradiation, radiation-induced swelling, grain size, microhardness.
DOI: 10.30791/1028-978X-2019-3-39-46
Kinev Evgenii — Stock company Institute of Nuclear Materials (29, Zarechny, Sverdlovsk region, 624250 Russia), PhD, leading scientist, specialist in structural material science. E-mail: kinev007@yandex.ru; irm@irmatom.ru.
Reference citing
Kinev Е. А. Korrelyaciya vysokodozovogo radiacionnogo raspuhaniya stali klassa 16 Cr – 15 Ni s razmerom zerna [Correlation between high-dose radiation-induced swelling and grain size of 16 Cr – 15 Ni steel]. Perspektivnye Materialy — Advanced Materials (in Russ), 2019, no. 3, pp. 39 – 46. DOI: 10.30791/1028-978X-2019-3-39-46
Physical-mechanical properties of composites based on vesuvianite and ethylene-butylene copolymer
N. T. Kakhramanov, I. V. Bayramova, N. S. Koseva, R. Sh. Gadzhieva
In work the results of investigation of influence of the concentration of the natural mineral filler of vesuvianite on main physical-mechanical and technological characteristics of composites based on ethylene-butylene copolymer have been presented. Such properties of composites as breaking stress, flexural modulus, specific elongation, heat resistance, and also melt flow index have been studied. The influence of a size of the vesuvianite particles on the above-mentioned properties has been also studied. The nano-sized (20 – 110 nm) and micro-sized (350 – 840 nm, 1420 – 2000 nm, 2210 – 4430 nm) of the vesuvianite fractions have been used. It has been established that at the same filler concentration with increase of particle sizes, a decrease of breaking stress and specific elongation of the samples, and also lowering in the heat resistance of the composite materials was observed. The explanation of the discovered regularities in a change of the structure and properties of the prepared composite materials has been presented. It has been shown that an introduction of the natural vesuvianite as a filler favors increase of melt flow index of the polymer composites. Apparently, such result has been connected with content of nanoclay, a layered structure of which contains glycerin and surfactants in the composition of vesuvianite. In the process of mixing on rollers and thermomechanical effect it occurs an intercalation of the polymer macrochains into the interlayer space of nanoclay with their subsequent destruction and isolation of polar liquids into polymer matrix, which improves the melt flow of composites.
Keywords: composites, ethylene-butylene copolymer, vesuvianite, viscosity, melt fluidity.
DOI: 10.30791/1028-978X-2019-3-47-53
Kakhramanov Najaf Tofig oglu — Institute of Polymer Materials of the National Academy of Sciences of Azerbaijan (Azerbaijan, Sumgayit, AZ 5004, S.Vurgun Str, 124), Dr Sci (Chem), professor, head of laboratory, specialist in the field of high-molecular compounds, chemical and mechanochemical modification and processing of polymers, research of nanocomposite materials based on mixture of polymers with mineral fillers. E-mail: najaf1946@rambler.ru.
Bayramova Ilaha Vilayet gizi — Institute of Polymer Materials of the National Academy of Sciences of Azerbaijan (Azerbaijan, Sumgayit, AZ 5004, S.Vurgun Str, 124), researcher, specialist in the field of chemistry and technology of composite materials. E-mail: ilahe.bayramova@sokar.az.
Koseva Nelya Stoyanova — Institute of Polymers of the Bulgarian Academy of Sciences (Sofia Akad. G. Bonchev St., block 103-A, BG - 1113 Sofia, Bulgaria), Dr Sci (Chem), director of Institute, specialist in the synthesis and research of polymer materials. E-mail: koseva@polymer.bas.bg.
Gadzhieva Reykhan Shahmardan gizi — Azerbaijan State Oil and Industry University (Azerbaijan, Bakı, Azadlıq prospekti, 16/21), PhD, Assistant of the Chair, specialist in the field of chemistry and technology of composite materials. E-mail: reyhan.haciyeva@gmail.com.
Reference citing
Kakhramanov N. T., Bayramova I. V., Koseva N. S., Gadzhieva R. Sh. Fiziko-mekhanicheskie svojstva kompozitov na osnove vezuviana i sopolimera ehtilena s butilenom [Physical-mechanical properties of composites based on vesuvianite and ethylene-butylene copolymer]. Perspektivnye Materialy — Advanced Materials (in Russ), 2019, no. 3, pp. 47 – 53. DOI: 10.30791/1028-978X-2019-3-47-53
Heat release kinetics and peculiarities of modified polymer-cement mixtures for construction 3D printing
V. A. Poluektova, N. A. Shapovalov, N. I. Novosadov
Modified by superplasticizers, polymer-cement mixtures based on water dispesions are gradually becoming one of the most promising materials for construction with the help of 3D technologies. The authors of the work have researched the heat release process during the hydration of the binder in polymer-cement mixtures and polymer-cement mixtures modified by phloroglucinefurfural superplasticizers. They have determined the specific enthalpy of the binder hydration in the presence of the polyvinyl acetate in the form of polyvinyl acetate dispersion and redispersable polymeric powder. It has been stated that the specific enthalpy of polyvinyl acetate polymer-cement systems is positive and that proves the endorthem of the total process. The article contains the information about the dependence of the heat release absolute values on the time of the binder hydration during the initial period of material solidifying process in the presence of organic components of the mixture (polyvinyl acetate and phloroglucinefurfural modifier). This reserach work proves that while modifying polymer-cement systems one can witness the lowering of the heat release peak, the reducing of the first period length of hydration and the increasing of the second (inductive) period length. The authors present the kinetic curves of heat release of modified polyvinyl acetate mixtures and examine the hudration peculiarities of the investigated systems. It has been determined that at the beginning of the hardening process the polyvinyl acetate increases and the phloroglucinefurfural superplasticizer reduces the heat release speed but partial levelling of the process can be watched when modifying the polymer-cement systems with the aim of the polymer in the form of polymer dispersion.
Key words: polymer-cement materials, heat release kinetics, enthalpy, hudration, polyvinyl acetate, phloroglucinefurfural modifier, consrtruction 3D printing.
DOI: 10.30791/1028-978X-2019-3-54-61
Poluektova Valentina — Belgorod State Technological University named after V.G. Shukhov (46 Kostyukova street, Belgorod, 308012, Russian Federation), Candidate of technical sciences, assistant professor, assistant professor, specialist in the sphere of chemical modification of highly-concentrated mineral and polymineral dispersions. E-mail: val.po@bk.ru.
Shapovalov Nickolai — Belgorod State Technological University named after V.G. Shukhov (46 Kostyukova street, Belgorod, 308012, Russian Federation), Dr Sci (Eng), professor, professor, specialist in the sphere of chemical modification of mineral building compositions. E-mail: rector@intbel.ru.
Novosadov Nickolay — Belgorod State Technological University named after V.G. Shukhov (46 Kostyukova street, Belgorod, 308012, Russian Federation), student pursuing bachelor’s degree in Technology and processing of polymers. E-mail: mcrunnerofficialmail@gmail.com.
Reference citing
Poluektova V. A., Shapovalov N. A., Novosadov N. I. Kinetika teplovydeleniya i osobennosti gidratacii modificirovannyh polimercementnyh smesej dlya stroitel'noj 3D-pechati [Heat release kinetics and peculiarities of modified polymer-cement mixtures for construction 3D printing]. Perspektivnye Materialy — Advanced Materials (in Russ), 2019, no. 3, pp. 54 – 61. DOI: 10.30791/1028-978X-2019-3-54-61
Synthesis of composite material in Al – Ti – B system during combustion of titanium and boron powders and aluminum-clad granules of VT6 alloy
M. A. Ponomarev, V. E. Loryan
Self-propagating high-temperature synthesis (SHS) in the combustion mode was carried out in the mixtures consisting of titanium fine powders with dendritic particles and amorphous boron, Ti+2B, with addition of aluminum-clad large spherical granules of titanium alloy VT6. The aim of the study was to obtain a composite material in one technological stage by SHS in the Al – Ti – B system. The synthesis in the combustion wave occurred stage-by-stage. Initially, a chemical reaction took place between boron and fine titanium; it resulted in boride framework around large clad particles. Simultaneously, this reaction acted as a “chemical stove”, causing heating and melting of the cladding layer, and the subsequent reaction of aluminum with titanium alloy granules. The melt appearing during the reaction in the clad granules spread along the pores and capillaries into the boride matrix. The non-monotonic shape of the recorded thermograms reflects the stages of the synthesis process and the heterogeneity of the reacting mixtures. The synthesized material has a developed porous and composite structures, which can be seen from elemental, microstructural and phase analyses. There are four scales in the pore size in the combustion product. Large spherical pores appear on the place of the granules. Due to layer-by-layer compaction of the mixture, the ordered arrangement of coarse particles in the initial compacts causes an ordered arrangement of macropores in the synthesis product.
Keywords: self-propagating high-temperature synthesis (SHS), composite materials, titanium diboride, intermetallic, phase formation.
DOI: 10.30791/1028-978X-2019-3-62-73
Loryan Vazgen — Merzhanov Institute of Structural Macrokinetics and Materials Science, Russian Academy of Sciences (ISMAN, Academician Osipyan str., 8, Chernogolovka, Moscow Region, 142432, Russia), Dr Sci (Eng), head of laboratory. E-mail: loryan@ism.ac.ru.
Ponomarev Michael — Merzhanov Institute of Structural Macrokinetics and Materials Science, Russian Academy of Sciences (ISMAN, Academician Osipyan str., 8, Chernogolovka, Moscow Region, 142432, Russia), PhD, senior researcher. E-mail: map@ism.ac.ru.
Reference citing
Ponomarev M. A., Loryan V. E. Sintez kompozicionnogo materiala v sisteme Al – Ti – B pri gorenii poroshkov titana, bora i plakirovannyh alyuminiem granul splava VT6 [Synthesis of composite material in Al – Ti – B system during combustion of titanium and boron powders and aluminum-clad granules of VT6 alloy]. Perspektivnye Materialy — Advanced Materials (in Russ), 2019, no. 3, pp. 62 – 73. DOI: 10.30791/1028-978X-2019-3-62-73
Used of experimentally determined parameters
of the cohesive zone in the numerical evaluation
of the resistance to delamination of polymer composites materials
P. G. Babayevsky, N. V. Saliyenko, G. V. Novikov
The technique of cohesive zones makes it possible to evaluate the stability of the material, both at the beginning of the crack propagation and to the appearance and development of defects in the places of stress concentration. The ability to reliably determine the parameters of fracture of polymer composite materials and to predict the behavior of structural elements from them under loading is an actual task for aerospace industry. It is proposed to use the length of the cohesive zone in the finite-element 3D model for mode I of interfacial delamination of the carbon fiber composite laminates in the form of a double cantilever beam (DCB). The length of the cohesive zone has calculated from the experimentally determined parameters such as the local interlayer cohesive strength of the material and the critical strain energy release. The determined length of the cohesive zone is used in the model to select the minimum number of finite elements at their optimum size, which ensures a higher accuracy of calculations of the main parameters of fracture toughness of carbon fiber composite laminates. As a result of the research, the main parameters of crack resistance were determined and the optimal length of the interface elements was chosen. The obtained model accurately describes the process of crack growth along the entire length of the cohesive zone, and the results of its application correlate well with the results of the experiments.
Key words: carbon fiber composite laminates, double-cantilever beam (DCB), parameters of the cohesive zone, experimental techniques, finite element 3D model of delamination DCB.
DOI: 10.30791/1028-978X-2019-3-74-81
Babaevsky Peter — Moscow Aviation Institute (National Research University MAI), (121552, Moscow, ul. Orshanskaya 3), Dr Sci (Eng), professor, head of department Technologies of Composite Materials, Structures and Microsystems, specialist in the field of material science and technology of polymer composites. E-mail: gena@mati.ru.
Salienko Nicholas — Moscow Aviation Institute (National Research University MAI), (121552, Moscow, ul. Orshanskaya 3), PhD, associate professor of Technologies of composite materials, structures and microsystems, specialist in the field of Material Science and Technology of polymer composites. E-mail: intdep@mati.ru.
Novikov Gennady — Moscow Aviation Institute (National Research University MAI), (121552, Moscow, ul. Orshanskaya 3), post-graduate student of Technologies of Composite Materials, Structures and Microsystems, specialist in the field of Material Science and Technology of polymer composites. E-mail: ngv92@mail.ru.
Reference citing
Babayevsky P. G., Saliyenko N. V., Novikov G. V. Ispol'zovanie ehksperimental'no opredelennyh parametrov kogezionnoj zony pri chislennoj ocenke ustojchivosti k rassloeniyu polimernyh kompozitov [Used of experimentally determined parameters of the cohesive zone in the numerical evaluation of the resistance to delamination of polymer composites materials]. Perspektivnye Materialy — Advanced Materials (in Russ), 2019, no. 3, pp. 74 – 81. DOI: 10.30791/1028-978X-2019-3-74-81
