21 Result(s)

Article

Modifying Effect of Polyethylene Fractions of Different Molecular Weights on the Morphology and Properties of Reactor Polymer Compositions Based on Ultrahigh Molecular Weight Polyethylene

Reactor polymer compositions (RPCs) based on UHMWPE with M_w = 1000 kg mol^–1 and low molecular weight HDPE (LMWPE) were studied. Two series of UHMWPE compositions were used to determine the influence of the molecu...

S. S. Gostev, E. E. Starchak, T. M. Ushakova, V. G. Grinev… in Polymer Science, Series A (2023)

Article

Polymer–Polymer Blends of Ultrahigh-Molecular-Weight Polyethylene and Low-Molecular-Weight High-Density Polyethylene: Synthesis, Morphology, and Properties

Polymer–polymer blends of ultrahigh-molecular-weight polyethylene (UHMWPE) and of low-molecular-weight high-density polyethylene (LMWPE) that contained 30, 50, and 80 wt % UHMWPE, were synthesized in a two-sta...

T. M. Ushakova, E. E. Starchak, S. S. Gostev… in Russian Journal of Physical Chemistry B (2020)

Article

Use of Synthetic and Natural Zeolites for Fabricating Immobilized Olefin Polymerization Catalysts and Polyolefin-Based Composite Materials

Synthetic zeolites differing in composition, framework parameters, and exchange cations that balance charges of aluminum–oxygen framework tetrahedra and natural finely divided clinoptilolite-containing tuffs h...

I. N. Meshkova, T. M. Ushakova, V. G. Grinev, V. A. Nikashina… in Petroleum Chemistry (2019)

Article

Raman structural study of random copolymers of ethylene with 1-hexene

Ethylene/1-hexene copolymers, which differ significantly in 1-hexene content (from 1.9 to 37.0 mol %), are studied by Raman spectroscopy. The copolymer spectra are compared with the Raman spectra of polyethyle...

Yu. V. Zavgorodnev, K. A. Prokhorov, L. A. Novokshonova, T. M. Ushakova… in Laser Physics (2012)

Article

Ethylene polymerization and ethylene-1-hexene copolymerization over immobilized metallocene catalysts

Ethylene polymerization and ethylene-1-hexene copolymerization in the presence of metallocene catalysts based on Cp₂ZrCl₂, rac-Et(Ind)₂ZrCl₂, rac-Me₂Si(2-Me-4-Ph-Ind)₂ZrCl₂, and rac-Me₂Si(2-Me-4-Ph-Ind)₂HfCl₂ bee...

T. M. Ushakova, E. E. Starchak, V. G. Krasheninnikov… in Kinetics and Catalysis (2012)

Article

Immobilized organometallic catalysts in the catalytic polymerization of olefins

Studies in the field of supported Ziegler-Natta catalysts employed for the polymerization of olefins that were begun by works performed under the guidance of Prof. Chirkov are reviewed in brief. The developmen...

L. A. Novokshonova, I. N. Meshkova, T. M. Ushakova… in Polymer Science Series A (2008)

Article

Modification of polyolefins as a modern strategy to designing polyolefin materials with a new complex of properties

Experimental data on multistage catalytic olefin polymerization processes are generalized. Such processes as the sequential homo-and copolymerization of ethylene and α-olefins; the copolymerization of ethylene...

I. N. Meshkova, T. M. Ushakova, N. M. Gul’tseva, V. G. Grinev… in Polymer Science Series A (2008)

Article

Olefin polymerization on immobilized zirconocene catalysts containing alkylaluminoxanes synthesized on the support surface

Ethylene and propylene polymerization on immobilized catalysts of composition MMT-H₂O/AlR₃/Zr-cene (MMT = montmorillonite) and on the corresponding homogeneous catalysts of composition Zr-cene-MAO (Zr-cene = rac-...

T. M. Ushakova, M. V. Lysova, O. I. Kudinova, T. A. Ladygina… in Kinetics and Catalysis (2007)

Article

Heterogenized methylaluminoxane and isobutylaluminoxane as activators for metallocene catalysts

Heterogenized alkylaluminoxanes prepared in situ on the montmorillonite (MMT) surface by the partial hydrolysis of AIR₃ with water of the support are effective activators for metallocenes. The thermal destruction...

L. A. Novokshonova, T. M. Ushakova, V. G. Krasheninnikov… in Kinetics and Catalysis (2006)

Article

Partially Hydrolyzed Alkylaluminums as the Active Heterogenized Components of Metallocene Catalysts

The heterogenized reaction products of the partial hydrolysis of the organoaluminum compounds AlMe₃ and Al(i-Bu)₃ with water as a constituent of highly hydrated supports, zeolite (ZSM-5-H₂O) and montmorillonite (...

L. A. Novokshonova, N. Yu. Kovaleva, T. M. Ushakova… in Kinetics and Catalysis (2005)

Article

Ethylene polymerization with catalysts on the base of Zr-cenes and methylaluminoxanes synthesized on zeolite support

I. N. Meshkova, T. M. Ushakova, T. A. Ladygina, N. Yu. Kovaleva… in Polymer Bulletin (2000)

Article

Influence of the catalyst matrix structure of the supported Ziegler-Natta catalysts on the homo- and copolymerization of olefins

The vanadium catalytic complexes immobilized on the same support (aluminium hydroxide, AH) and distinguished by structure and composition have been compared for ethylene and propylene homo- and copolymerizatio...

I. N. Meshkova, T. M. Ushakova, N. M. Gul’tseva, M. N. Larichev… in Polymer Bulletin (1997)

Article

Influence of the nature of monomers on the activity of supported titanium catalysts in the α-olefin polymerization

Ethylene and propylene co-polymerization and sequential polymerization with high activity supported titanium catalysts were studied. Specific rate of homopolymerization and copolymerization constants for ethyl...

N. M. Gul'tseva, T. M. Ushakova, A. M. Aladyshev, L. N. Raspopov… in Polymer Bulletin (1992)

Article

Methylation of olefins with organic reagents in the presence of rhodium compounds

I. Ya. Levitin, L. G. Volkova… in Bulletin of the Academy of Sciences of the… (1973)

Article

Butadiyne derivatives

1. The reaction of 1-buten-3-ynyl sulfides with water under various conditions was investigated. Under the influ...

A. N. Dolgikh, A. V. Bogdanova… in Bulletin of the Academy of Sciences of the… (1964)

Article

Vinyl compounds in the diene synthesis

1. A study was made of the peroxyacetic acid oxidation of the adducts formed by aryl vinyl and alkyl vinyl sulfi...

M. F. Shostakovskii, A. V. Bogdanova… in Bulletin of the Academy of Sciences of the… (1961)

Article

The diene synthesis with participation of vinyl ethers

1. Reaction of divinyl ether with hexachlorocyclopentadiene gives, depending on the experimental conditions, var...

M. F. Shostakovskii, A. V. Bogdanova… in Bulletin of the Academy of Sciences of the… (1961)

Article

Vinyl compounds in diene synthesis

1. The reactivity of vinyl ethers containing hydroaromatic radicals in the diene synthesis with cyclopentadiene ...

M. F. Shostakovskii, A. V. Bogdanova… in Bulletin of the Academy of Sciences of the… (1961)

Article

Vinyl compounds in diene synthesis

1. The diene condensations of 2-naphthyl vinyl ether and of p-t-butylphenyl vinyl ether with cyclopentadiene and...

M. F. Shostakovskii, A. V. Bogdanova… in Bulletin of the Academy of Sciences of the… (1960)