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1.
Russian Journal of Applied Chemistry - Commercial samples of butadiene–styrene copolymers were studied by NMR spectroscopy in a magnetic field of 16.4 T (protons Larmor frequency 700 MHz). A... 相似文献
2.
Russian Journal of Applied Chemistry - Polyisoprenes synthesized on titanium–magnesium catalysts were studied by 1H and 13C NMR spectroscopy (Larmor’s frequency for protons 700 MHz).... 相似文献
3.
N. Makhiyanov D. Kh. Safin A. S. Khachaturov 《Russian Journal of Applied Chemistry》2010,83(6):1037-1043
Commercial and laboratory samples of polyoxypropylenepolyols were studied by 1H NMR spectroscopy at operating frequencies of 100 and 500 MHz. Various methods depending on the solvent used were suggested
for determining the equivalent weight (molecular weight of the polyether per terminal hydroxy group). The 1H NMR data are compared to the data obtained by chemical methods and gel permeation chromatography. 相似文献
4.
Industrial samples of polybutadiene rubbers with a high (95% or more) content of cis-1,4-units obtained on the neodymium-containing catalysts are studied by GPC and NMR spectroscopy (600 MHz). The GPC data obtained under different experimental conditions are analyzed taking into account the molecular weight calculated from NMR data. As a result, the coefficients of the Kuhn–Mark–Houwink–Sakurada equation for the solutions of cis-polybutadiene rubbers in toluene and tetrahydrofuran are refined. 相似文献
5.
DSC and NMR are employed to determine the glass-transition temperatures and the structural features of polybutadienes with
widely varying configuration isomeric compositions. The dependences of the glass-transition temperature on the contents of
cis-1,4-, trans-1,4, and 1,2-units in polybutadiene chains are plotted and discussed. An analysis of the experimental results and the published
data suggests that, in the study of the glass-transition-structure relationship, simplified approaches are inapplicable and
it is necessary to consider the configurational and conformational geometry of polybutadiene chains. 相似文献
6.
The 1H NMR spectra (working frequencies of 500 and 600 MHz) of polychloroprenes are studied. The spin systems of protons for monomer
units of different configurations (1,2, 3,4, 1,4-cis-and 1,4- trans- units), as well as for dyad and triad combinations of 1,4 units, are classified. A high working frequency, the method of
double resonance, and the calculation of chemical shifts by empirical increments make it possible to refine the assignment
of 1H NMR signals. 相似文献
7.
N. Makhiyanov 《Journal of Applied Spectroscopy》1994,61(1-2):509-513
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N. Makhiyanov 《Russian Journal of Applied Chemistry》2011,84(3):454-460
Commercial samples of chloroprene rubbers were studied by high-resolution NMR spectroscopy (600 MHz). 1H and 13C NMR proved to be efficient in quantitative analysis of the microstructure of polychloroprenes. 相似文献
9.
N. Makhiyanov D. Kh. Safin R. R. Sharifullin A. S. Biktimerova 《Russian Journal of Applied Chemistry》2012,85(12):1879-1886
13C NMR spectroscopy was used to make a comparative characterization of the distribution of polyoxypropylene polyols synthesized on basic (KOH) and dimetal cyanide catalysts over the type of functionality, regioregularity, and stereotacticity. 相似文献
10.