Registration Number
0216U005734,
0115U003099
, R & D reports
Title
Obtaining of modified monomers for epoxy resins and polyoxotungstates for creating new materials
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Head
Shved Olena M., Доктор хімічних наук
Registration Date
10-02-2016
Organization
Donetsk National University
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In order to develop fundamental approaches to the multi-purpose functional polymer and composite materials creation is established: Opening of the oxirane ring follows simultaneously SN2 and borderline SN2 mechanisms. The regioselectivity of the acidolysis of substituted oxiranes is determined by acid-base properties of the reactants and catalysts and steric factor. The regioselectivity increases as the contribution of the SN2 mechanism increases. It is shown the complexes are decomposed under the epoxy resin's action with amine releasing and formation new complex ED-20·BF3 at the initial polymerization stage. The presence of the last one promotes the two flows of reaction: the 1st - the catalysis of ED-20 homopolymerization by BF3 and the 2nd - curing ED-20 by primary and secondary amines or the catalysis of ED-20 homopolymerization by tertiary amines. The contribution of each flows depends on the amine nature. In order to develop new techniques for synthesis of lanthanide containing polyoxotungstates and polyoxomolybdates for further creation of new materials revealed the following. The conditions for the synthesis of a new Ln-containing heteropolytungstates Na9[Dy(W5O18)2]·30H2O and Na9[Sm(W5O18)2]·30H2O from the aqueous solution, acidified to Z=?(H+)/?(WO42-)=0.80 with acetone adding, were determined. FTIR spectroscopy was used to show that the anion within the synthesized salt has a Peacock-Weakley structure. The method for obtaining sodium heteropoly decatungstolanthanidates (III), described in this research, is a new one and it allows to synthesize a neutral salt; in future this can be used in synthesis of neutral salts Na9[Ln(W5O18)2]·nH2O with other Ln-heteroatoms. X-ray analysis revealed that the thermolysis of Na9[Dy(W5O18)2]·30H2O results in formation of Na2W2O7 and Na0.5Dy0.5WO4. Scanning electron microscopy confirmed the single-phaseness of the synthesized salt, and showed that the grain size of Na9[Dy(W5O18)2]·30H2O is within 130-180 nm. X-ray analysis revealed that the thermolysis of Na9[Sm(W5O18)2]·30H2O results in formation of Na2W2O7 and Na0.5Sm0.5WO4. Scanning electron microscopy confirmed the single-phaseness of the synthesized salt, and showed that the grain size of Na9[Sm(W5O18)2]·30H2O is within 250-550 nm. The procedure of synthesis of the amorphous dysprosium and samarium paratungstates B using the exchange reaction from sodium paratungstate B were elaborated. The isolated salts were characterized by methods of chemical analyses, FTIR spectroscopy and X-ray diffraction. Scanning electron microscopy confirmed the single-phaseness of the synthesized salt, and showed that the grain size of Dy10[W12O40(OH)2]3·100H2O is within 300 750 nm, and that the grain size of Sm10[W12O40(OH)2]3·104H2O is within 250 550 nm. It is established that the limits of isomorphic substitutions in the range of systems Nd5-xLaxMo3O16, Nd5-xCexMo3O16 and Nd5-xPrxMo3O16 mainly increase. This is caused by decrease in differences for the radii of triply charged ions from 0.051 ? (in case of neodymium substitution with lanthanum) to 0.017 ? (in case of neodymium substitution with praseodymium). Lower value of the substitution limit in the system with Ce, compared to the La containing system, is explained by the fact that it is not isovalent substitution of Nd3+ with Ce3+, but a heterovalent substitution of Nd3+ with Ce4+, which takes place in the former one. This significantly increases the energy of mixing due to increasing differences in the charges of replaceable structural units and their increasing size (the difference between the radii of Nd3+ and Ce4+ is 0.139 ?). In the areas of solid solutions of all the systems, the values of specific conductivity increase as the degree of substitution increases. However, this occurs for different reasons. In the systems Nd5-xPrxMo3O16 and Nd5-xLaxMo3O16 as cations with larger ionic radii compared to Nd3+ enter the structure this occurs due to the increase in the size of interstices, along which the oxygen anions move. In the system Nd5-xCexMo3O16 the quantity of moving oxygen anions increases as a result of heterovalent substitution of Nd3+ with Ce4+. The results obtained can be applied for the development of new solid electrolytes based on Nd5-xLnxMo3O16 and the related systems. In order to develop of new analytical techniques of concentrating, extracting and determination of metal revealed follows. An extraction system "isopropyl alcohol-water-ammonium sulfate" for selective extraction of bismuth (III) iodide complex and its spectrophotometric determination was proposed. A procedure for the photometric determination of bismuth (III), verified by the "put-found" on the model solution containing the Fe (III), Al (III), Ni (II), Co (II), Cr (III) were elaborated. It is found that the relative standard deviation does not exceed 0.03. The proposed technique for determination of bismuth is simple, using low-risk, affordable extractants.
Product Description
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Іванцова Елла Сергіївна
Беспалько Юлія Миколаївна
Гетьман Євген Іванович
Калінський Олександр Михайлович
Марійчак Олександра Юріївна
Мельниченко Василь Іванович
Радіо Сергій Вікторович
Ситник Наталя Сергіївна
Ютілова Ксенія Сергіївна
Яни Марія Валеріївна
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2020-04-02
