Chemistry & Chemical Technology最新文献

{"title":"Polymeric Composite Materials of Tribotechnical Purpose with a High Level of Physical, Mechanical and Thermal Properties","authors":"O. Kabat, V. Sytar, O. Derkach, K. Sukhyy","doi":"10.23939/chcht15.04.543","DOIUrl":"https://doi.org/10.23939/chcht15.04.543","url":null,"abstract":"Polymeric composites (PC) of tribological applications with a high level of physical, mechanical and thermal properties based on aromatic polyamide and silica gel have been developed. Regularities have been obtained that describe the effect of the filler content in PC on the friction coefficient, temperature on the friction surface and the intensity of linear wear rate of the studied PC-steel friction pair. It was found that the optimal silica gel content in the polymer matrix is 10 wt %. The morphology of the steel surface of friction after friction interaction with PC based on aromatic polyamide and silica gel was studied. The formation of an antifriction film on the steel surface of friction was discovered, which contributes to a decrease in the friction coefficient, temperature on the friction surface, and the linear wear intensity of the studied PC. The influence of the load and sliding speed on the main tribotechnical characteristics of the PC-steel friction pair has been studied. Mathematical laws were derived that describe the influence of the main external factors (load and sliding speed) on the friction coefficient and intensity of linear wear rate of the studied friction pair. Physical, mechanical and thermal investigations of the developed PC were carried out and it was found that the introduction of 10 wt % silica gel contributes to their 5–10 % increase.","PeriodicalId":9793,"journal":{"name":"Chemistry & Chemical Technology","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91216421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Studying the Insulating Properties of Oxide Films Obtained on the Ti6A14V Alloy in Tartaric Acid Solutions Using the Method of Electrochemical Decoration by Copper","authors":"O. Pylypenko, O. Smirnova, Olga Skorynina-Pohrebna, O. Khoroshev","doi":"10.23939/chcht15.04.526","DOIUrl":"https://doi.org/10.23939/chcht15.04.526","url":null,"abstract":"The investigation data of the formation peculiarities of oxide films on the Ti6A14V alloy in tartaric acid solutions have been given. It is shown that the behavior of alloy forming dependences is conditioned by the anode current density. At ja < 0.5 A∙dm-2 the continuous oxide film is not formed on the alloy surface and the preset value of the final voltage on the cell is not reached. With an increase in ja > 0.5 A∙dm-2, alloy forming dependences show a linear behavior that is indicative of the formation of low porous films. In these conditions, the oxide film formation rate is in direct proportion to the value of ja. The electrochemical oxidation of Ti6A14V alloy in tartaric acid solutions results in the formation of interference-colored oxide films. The oxide film ultimate thickness and color are defined by the preset voltage and are independent of the current density and electrolyte concentration. The isolating properties of obtained films were studied by the way of the cathode polarization of oxidized specimens in the sulfate copper-plating electrolyte. The research done allows us to make a conclusion that electrochemical copper deposition is a convenient tool for the detection of defective spots in oxide films. It is shown that due to the specific features of the reduction kinetics of Cu2+ ions on the oxidized titanium it is reasonable to use for the studies the initial sections of polarization dependences that correspond to ΔE = 0.2–0.25 V. The alloy polarization dependences allow us to establish unavailability of apparent dependences between the oxidation current density, the electrolyte concentration, the cell final voltage value and the polarization that occurs during the Cu2+ ion reduction. The anodic connection of copper-coated specimens conditions the reversible dissolution of a greater portion of the specks of copper deposits. It is indicative of the electron conduction of film defects. The obtained data allow us to vary the electrolysis parameters in a wide range with no significant influence of the treatment mode of Ti6A14V alloy on the quality of oxide coatings.","PeriodicalId":9793,"journal":{"name":"Chemistry & Chemical Technology","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87470960","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Production of Bitumen Modified with Low-Molecular Organic Compounds from Petroleum Residues. 3. Tar Modified with Formaldehyde","authors":"V. Gunka, Y. Prysiazhnyi, Y. Hrynchuk, Iurii Sidun, Yuriy Demchuk, O. Shyshchak, O. Poliak, M. Bratychak","doi":"10.23939/chcht15.04.608","DOIUrl":"https://doi.org/10.23939/chcht15.04.608","url":null,"abstract":"The chemical modification of tar with formaldehyde as 37% aqueous solutionhas been studied in the presence of the catalysts. Hydrochloric acid, sulfuric acid, sodium hydroxide and acid tar were used as the catalysts. The effect of the catalyst nature and amount, as well as temperature, process time and initial components ratio on the softening point, penetration, brittle point and adhesion to crushed stone has been determined. The structure of the modified tars was confirmed by IR spectroscopy. The structural-group composition was determined. Arene-formaldehyde resins have been synthesized on the basis of toluene and modified tars using hydrochloric acid as a catalyst. The synthesized resins were characterized using IR spectroscopy. The chemistry of the tar modification with formaldehyde has been proposed.","PeriodicalId":9793,"journal":{"name":"Chemistry & Chemical Technology","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76574749","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Use of Mussel Shell as a Bio-Additive for Poly(Lactic Acid) Based Green Composites","authors":"Metehan Oğulcan Lap, Y. Kanbur, Ümit Tayfun","doi":"10.23939/chcht15.04.621","DOIUrl":"https://doi.org/10.23939/chcht15.04.621","url":null,"abstract":"Mussel shell is one of the most hazardous aquaculture wastes and its powder was used as an additive for bio-degradable poly (lactic acid) in this current study. Bio-composites were fabricated via conventional melt mixing technique followed by an injection moulding process. The effects of mussel shell powder inclusion on mechanical, melt-flow, water uptake and morphological performance of poly (lactic acid)-based green composites were reported.","PeriodicalId":9793,"journal":{"name":"Chemistry & Chemical Technology","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75435088","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental Investigation and Multi-Gene Genetic Programming Simulation of Portland Clinker Burnability","authors":"Vahab Ghalandari, Hamidreza Bagheri, A. Mohebbi, Hadi Esmaeili","doi":"10.23939/chcht15.04.559","DOIUrl":"https://doi.org/10.23939/chcht15.04.559","url":null,"abstract":"In this study, the effect of chemical composition of the raw material on the clinker burnability was studied by determination of free CaO (wt %) content of clinker. The burnability of two types of Portland clinker was investigated for silica modules of 2.3, 2.5 and 2.7 and lime saturation factor of 0.88–0.98. In addition, using the Multi-gene genetic programming (MGGP) model, the burnability of clinker was predicted. The results of MGGP model indicated that the performance of the model for predicting the amount of free CaO (wt %) was acceptable. Moreover, using MGGP, a promising correlation was introduced for accurately calculating the amount of free CaO (wt %). The performance of this correlation was compared with FL-Smidth, and it was established that the average errors of MGGP correlation and FL-Smidth equation were 2.95 and 7.45 %, respectively.","PeriodicalId":9793,"journal":{"name":"Chemistry & Chemical Technology","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76664138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characterization and Properties of Titanium(IV) Oxide, Synthesized by Different Routes","authors":"T. Dontsova, Anastasiya S. Kutuzova, A. Hosseini-Bandegharaei","doi":"10.23939/chcht15.04.465","DOIUrl":"https://doi.org/10.23939/chcht15.04.465","url":null,"abstract":"The article considers the influence of precursor type and sol-gel synthesis conditions of TiO2 on its properties. The obtained TiO2 samples were characterized by X-ray diffraction methods, electron microscopy, as a result of which it was found that all the obtained TiO2 powders have the crystallite size in a nanorange of 2.5–17 nm. It was shown that sorption-photocatalytic properties of TiO2 significantly depend on a phase composition, surface acidity, specific surface area and porosity. It was found that the amorphous TiO2 has improved adsorption properties, while crystalline TiO2 is characterized by enhanced photocatalytic properties. Determined acidic nature of the TiO2 surface explains the better sorption and photocatalysis relative to the cationic dye.","PeriodicalId":9793,"journal":{"name":"Chemistry & Chemical Technology","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81194844","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis and Cross-Linking Properties of Melamine Formaldehyde Oligomers with Peroxy Groups","authors":"O. Astakhova, O. Shyshchak, M. Bratychak","doi":"10.23939/chcht15.04.512","DOIUrl":"https://doi.org/10.23939/chcht15.04.512","url":null,"abstract":"Melamine formaldehyde oligomers with peroxy groups (MFOP) have been synthesized based on melamine or urea and melamine in the presence of tert-butyl peroxymethanol or tert-butyl hydroperoxide. Zinc oxide was used as a catalyst. The effect of peroxide nature, ratio of the starting components and process time on the characteristics and yield of MFOP has been studied. The structure of the synthesized MFOP was confirmed by IR- and PMR-spectroscopy. The chemistry of the cross-linked structures formation was studied. The possibility of using such oligomers as a cross-linking agent for the mixtures based on TGM-3 oligoesteracrylate is shown.","PeriodicalId":9793,"journal":{"name":"Chemistry & Chemical Technology","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82406390","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis of Antibacterially ActiveSilver Nanoparticles by Galvanic Replacement on Magnesium in Solutions of Sodium Polyacrylate in an Ultrasound","authors":"G. Zozulya, O. Kuntyi, R. Mnykh, M. Sozanskyi","doi":"10.23939/chcht15.04.493","DOIUrl":"https://doi.org/10.23939/chcht15.04.493","url":null,"abstract":"“Green” synthesis of silver nanoparticles (AgNPs) by a galvanic replacement (GR) on magnesium in solutions of sodium polyacrylate (NaPA) under ultrasound (42 kHz) is reported. The mechanism of combined action of GR and ultrasound on the formation of nanoparticles is proposed. Synthesized solutions of AgNPs are characterized by an absorption maximum at 410 nm, the value of which does not depend on the concentrations of precursors (AgNO3 and NaPA) and the duration of the process. The dimensions of nanoparticles that have a spherical shape do not exceed 30 nm. With increasing concentration of surfactant, there is a tendency to decrease in size. The rate of synthesis of AgNPs increases almost in proportion to the concentration of AgNO3 in the solution, while the effect of NaPA concentration is negligible. The synthesized nanoparticles efficiently demonstrated a bactericide effect on Escherichia coli and Staphylococcus aureus.","PeriodicalId":9793,"journal":{"name":"Chemistry & Chemical Technology","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81254235","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical and Chemical Studies of Al2O3-Ti Composites for Their Use as a Bone Substitute","authors":"Elizabeth Refugio-García, G. Vázquez-Huerta, J. Miranda-Hernández, J. Osorio-Ramos, José A. Rodríguez-García, E. Rocha-Rangel","doi":"10.23939/chcht15.04.591","DOIUrl":"https://doi.org/10.23939/chcht15.04.591","url":null,"abstract":"Alumina-based composites reinforced with titanium were manufactured by powder techniques. Characterizations indicate that titanium content affects densification which in turn causes positive effects on hardness and toughness. Microstructure presents grains of irregular shape and small sizes. Electrochemical impedance spectroscopy indicates that additions of titanium on Al2O3 enhance its corrosion resistance.","PeriodicalId":9793,"journal":{"name":"Chemistry & Chemical Technology","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75092746","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Synthesis and Structure of Urea-Formaldehyde Oligomers with Peroxide Groups","authors":"O. Astakhova, O. Shyshchak, M. Bratychak","doi":"10.23939/chcht15.03.369","DOIUrl":"https://doi.org/10.23939/chcht15.03.369","url":null,"abstract":"The possibility of synthesis in the presence of tert-butyl peroxymethanol (TBPM) or tert-butyl hydroperoxide (TBHP) of urea-formaldehyde oligomers with peroxide groups (UFOP) has been considered. Zinc oxide was used as the reaction catalyst. The effect of the initial components ratio, the reaction temperature and the process time on the characteristics and yield of the obtained oligomers was studied. Methods for obtaining UFOP using a mixture of TBPM and TBHP as a component are proposed. The structure of the synthesized UFOP was confirmed by IR- and NMR-spectroscopic studies.","PeriodicalId":9793,"journal":{"name":"Chemistry & Chemical Technology","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2021-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86098876","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}