Papers by Keyword: Tetraethoxysilane

Abstract: The disadvantage of reinforced concrete structures is their gradual destruction at high temperatures, above 250-300°C under the influence of fire, due to disturbance of cement binder structure. Therefore, the development of a fire-resistant composition for reinforced concrete is urgent. The article describes the study of tetraethoxysilane (TES) 6% and 10% as a fire retardant additive for sand-cement mortar, for building structures made of metal, the experimental study of sand-cement mortar using tetraethoxysilane 6% and 10%, with different methods of application to the metal is stated. An assessment of the effectiveness of TPP in interaction with sand-cement mortar is given.

Abstract: Based on the generalization of research results on the processes of obtaining SiO₂ sols using tetraethoxysilane and ethyl silicates, the main factors influencing the elasticity of silica coatings on cotton fabrics and their fire-retardant properties are considered. The possibility of forming covalent bonds between the functional groups of cellulose, gel coating and flame retardant layer is considered, which explains the strong fixation of a thin layer of coating on the fibers of the fabric and improve its fire protection. The use of the developed compositions for fire-retardant elastic coatings based on ethyl silicate allows to increase the time of complete burning of cotton from 30s (untreated fabric) to 600s (treated with binary coating).

Abstract: The use of complex fire-retardant coatings based on ethyl silicate gel - diammonium hydrogen phosphate reduces the process of smoke formation during thermal exposure to treated tissue samples, which is promising for improving the fire safety of textile materials. The compositions are easy to obtain, they do not require specific processing conditions, do not contain toxic substances. This allows us to offer developed compositions for fire protection of textile materials used in facilities with a large number of people.

Abstract: The work is devoted to the development of the technology for the formation of the required microrelief of the optical surfaces of glass-ceramic substrates. The solution of the problem using a controlled local deposition of silicon dioxide on the polished surface by laser pyrolysis of tetraethoxysilane vapor in the presence of ozone is shown. The characteristics of the experimental samples, their comparison with the data of mathematical modeling of the results of technological processes are presented. The possibility of using the developed technology for the production of substrates of optical parts with a defined wedge-shaped value is shown.

Abstract: The influence of the degree of homogeneity of the SiO₂ sol on the duration of the induction period and the quality of fire-resistant coatings on textile materials was studied. The prospects of using IR spectroscopy as an express method for studying the phase composition of a gel coating, the degree of completion of the hydrolysis of an organosilicon component, and adjusting the parameters for obtaining a high-quality fire-resistant binary coating of a sol SiO₂ - flame retardant system are shown.

Abstract: New materials based on oligooxidridsilmethylensiloxysilane nanostructured with ethyl ester of orthosilicic acid – tetraethoxysilane have been studied in the research. Tetraethoxysilane introduction into the composition is supposed to cause its decomposition up to nanoparticles of silicon oxide. The alkoxysilane hydrolytic destruction kinetics and the impact of the composition and nature of the polymer composition components on the physical properties have been studied. Atomic force microscopy was used to study the structurization kinetics of the polymer composition. The composition hydrophobicity was determined by the edge wetting angle. To study the adhesion characteristics of the obtained material, the method of disc separation from the substrate has been used. The relative rigidity has been determined by a pendulum device M3. Atomic force microscopy revealed the presence of nanoscale neoplasms (at average of one hundred twenty per one square micrometer) in diameter from two to five nanometers in the surface structure of the composition, modified with tetraethoxysilane. Herewith the physical properties of the material change: rigidity increases, the edge angle of wetting increases as well. The studied nanostructured compositions can also be applied. For example – they can be used as a protective coating with a set of special properties, such as high hydrophobicity.

Abstract: Nowadays, nanostructures made on the basis of mixed oxides are of great interest for fundamental scientific and applied researches because of its potential applications, such as photo catalysts, luminophores, sensitive elements of gas sensors and vacuum sensors. The article describes nanostructural properties of NiO–Al₂O₃–SiO₂ prepared by sol-gel method. Nanocomposites were obtained by mixing a solution of Si (OC₂H₅)₄ (TEOS) as a SiO₂ precursor with a solution containing Al (NO₃)₃ · 9H₂O and Ni (NO₃)₂ · 6H₂O. Ethanol was used as solvent. The gel was dried at room temperature and annealed in the 100–500 °C range. The behavior of chemical bonds is considered by using FTIR technique. Crystallization of NiO phase at 500 °C is observed in XRD patterns. Aluminum atoms are incorporated into silica matrix, which was confirmed by XRD. The amorphous structures which are desirable for next generations are formed at room temperature.

Abstract: The paper considers the formation of silicon oxides and d-metals using differential-scanning calorimetry data of the film-forming solutions hydrolysates containing tetraethoxysilane and d-metal salts. The major stages of double oxides SiO₂-M_xO_y (where M – Mn, Fe, Co, Ni) formation, and behavior of the systems upon the application of heat are analyzed. Thermal treatment intervals which display the difference of the systems behavior depending on the metal nature were determined.

Abstract: The paper studies the formation of thin-film and disperse SiO₂-M_xO_y systems (where M – Mn, Fe, Co, Ni) synthesized with sol-gel technology. The influence of metal salt on tetraethoxysilane hydrolysis and film-forming solution viscosity is considered. Dependence of the film optical properties on their composition was determined.

Abstract: Three kinds of functionalized imidazolium ionic liquid, 1-chloride (2-hydroxyethyl) -3-methyl imidazole ionic liquid [HeMIM]Cl, 1-bromide ethylamine-3-methyl imidazolium ionic liquid [AeMIM]Br and chlorinated 1-carboxyethyl-3-methyl imidazolium ionic liquid [CeMIM]Cl, were synthesized firstly. Subsequently, three kinds of supported silicon imidazolium ionic liquids were prepared from above ionic liquids with tetraethoxysilane by sol-gel method. The Chemical structure and crystal structure of the supported on silica based ionic liquids were analyzed by FTIR and XRD.