Zobrazeno 1 - 10
of 55
pro vyhledávání: '"S.G. Alekseyeva"'
Autor:
V.V. Korshak, S.G. Alekseyeva, Ya.G. Urman, V.A. Bairamov, V.M. Gladyshev, I.Ya. Slonim, O.V. Smirnova
Publikováno v:
Polymer Science U.S.S.R.. 17:2778-2783
Mixed polycarbonates have been prepared by interfacial polymerization of the bisphenols 2,2-di-(4-hydroxyphenyl)propane (DMPP), 1,1-di-(4-hydroxyphenyl) cyclohexane (DPC), 5,5-di-(4-hydroxyphenyl)-4, 7-methanohexahydroindane (DPHMI), di-(4-hydroxyvan
Publikováno v:
Polymer Science U.S.S.R.. 20:1673-1678
The composition and structure of siloxane-urethane copolymers obtained by non-equilibrium, low temperature polycondensation, have been investigated by PMR spectroscopy. It is shown that in one stage, non-equilibrium, heterogeneous copoly-condensation
Autor:
Cherkashin Mikhail I, E. F. Oleinik, L.S Kol'tsova, M. G. Chauser, Ya.G. Urman, L. V. Vladimirov, S.G. Alekseyeva, N. L. Zaichenko
Publikováno v:
Polymer Science U.S.S.R.. 30:1539-1546
Data are given on the IR spectra of polyphenylacetylenes obtained on polymerization of phenylacetylene under the action of heat (A), WCL6 (B), Al(C2H5)3TiCl2 (C), and Co(AcAc)3Al(C2H5)3 (D). In their cis-unit content the polyphenylacetylenes st
Publikováno v:
Polymer Science U.S.S.R.. 19:899-909
A 13 C-NMR method has been developed for the determination of the structure of urea-formaldehyde resins. The signals have been identified on the basis of spectra produced from a number of model compounds, and the dependence of the spectra on the urea
Autor:
I.Ya. Slonim, B.Ya. Aksel'rod, S.G. Alekseyeva, B. M. Arshava, L.N. Smirnova, I.M. Gurman, Ya.G. Urman
Publikováno v:
Polymer Science U.S.S.R.. 20:2569-2576
A quantitative description of the structure of urea-formaldehyde resins by means of the 13 C-NMR spectra has been developed. The structure has been investigated at all stages of synthesis and during the initial stages of setting. The branched structu
Autor:
I.Ya. Slonim, G.N. Kovalev, V.V. Korshak, Ya.G. Urman, S.G. Alekseyeva, B.S. El'tsefon, I.M. Raigorodskh, A.I. Kuzayev, E.Sh. Gol'dberg
Publikováno v:
Polymer Science U.S.S.R.. 26:1529-1538
In conditions of heterophase polycondensation new polysiloxane-polycarbonate urethane block copolymers have been synthesized displaying a biphasic morphology. Study of the reaction of the initial oligomers in various heterophasic systems showed that
Publikováno v:
Polymer Science U.S.S.R.. 27:1993-1999
A method has been devised for determining from the 13 C NMR spectra the structure of the products of interaction of furfuryl alcohol with urea and formaldehyde. Hemiformals form in a neutral medium. Boiling at pH 5·5 leads to the formation of dimeth
Publikováno v:
Polymer Science U.S.S.R.. 19:920-936
A method has been developed for 13C NMR analysis of the structure of urea-formldehyde resins containing imidazolidone, triazinone and uronic rings. It is shown that the reaction of urea and formaldehyde with ammonia or hexamethylene tetramine results
Publikováno v:
Polymer Science U.S.S.R.. 20:1598-1608
A method was developed to determine the structure of urea-formaldehyde resins using NMR 1H spectra of solutions in D2O. Spectra were obtained of model compounds of linear cyclic structure, model systems and resins of industrial type and the signals w
Publikováno v:
Polymer Science U.S.S.R.. 16:2965-2969
The Monte Carlo method was used fo calculating the isomeric composition of phenolformaldehyde novolac polymers. Good agreement between calculated and experimental results was obtained.