Isoprene Polymerisation in the Presence of Catalytic Systems based on Gadolinium Compounds

Levkovskaya, E.I.; Bubnova, S.V.; Bodrova, V. S.; Drozdov, B.T.; Васильев, В. А.

doi:10.1177/0307174x1404100904

Cited by 5 publications

(6 citation statements)

References 3 publications

(4 reference statements)

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“…Among the lanthanides, gadolinium stands out as a potential competitor to neodymium used in industry. It was found in [10][11][12][13][14] that gadolinium-based catalytic systems exhibit higher stereoselectivity in comparison with neodymium metal complex systems and have sufficient activity in diene polymerization reactions. This circumstance and the lower cost of gadolinium compounds relative to neodymium [15][16][17] justify the prospect of their industrial use.…”

Section: Introductionmentioning

confidence: 99%

Comparative ONIOM modeling of 1,3‐butadiene polymerization using Nd(III) and Gd(III) Ziegler–Natta catalyst systems

Masliy,

Akhmetov,

Kuznetsov

et al. 2023

Int J of Quantum Chemistry

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On the base of structural and thermodynamic data using modern methods of quantum chemistry, a comparative theoretical study of the elementary acts of initiation and growth of a polymer chain during the polymerization of 1,3‐butadiene was carried out. Ziegler–Natta catalysts based on Nd(III) and Gd(III) were used as polymerization initiators. It was shown that the higher stereospecificity of the action of gadolinium catalytic complexes in comparison with neodymium complexes is due to the increased stability of the anti‐form of the π‐allylic terminal structure of the growing polymer chain, and the reduced activity is due to the higher activation energy of the processes of initiation and chain growth.

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Section: Introductionmentioning

confidence: 99%

Comparative ONIOM modeling of 1,3‐butadiene polymerization using Nd(III) and Gd(III) Ziegler–Natta catalyst systems

Masliy,

Akhmetov,

Kuznetsov

et al. 2023

Int J of Quantum Chemistry

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“…Industrial isoprene polymerization based on lanthanide catalytic systems can include neodymium chloride 3 and gadolinium. 4 The gadolinium catalyst based polyisoprene production was initiated at the turn of 2017–2018. Meanwhile, much experimental evidence has been accumulated for neodymium chloride polyisoprenes produced both periodically and continuously.…”

Section: Introductionmentioning

confidence: 99%

“…Previous studies have found a distinct advantage of this type of catalyst in producing cis-1,4 polymers that make them highly popular. Industrial isoprene polymerization based on lanthanide catalytic systems can include neodymium chloride and gadolinium . The gadolinium catalyst based polyisoprene production was initiated at the turn of 2017–2018.…”

Section: Introductionmentioning

confidence: 99%

Assessing the Hydrodynamic Effect on the Molecular Parameters of the Isoprene Polymerization Product in the Presence of a Neodymium-Based Catalytic System

et al. 2022

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The paper presents findings on the kinetic regularities of polyisoprene production in the presence of neodymium-based catalytic systems for large-scale production processes. A mathematical model has been developed for batch and continuous isoprene polymerization. The study identified dependences of changes in the number-average and mass-average molecular weight of the resulting product on the length of the applied reactor cascade under continuous static operation. The description of the continuous production mode leads to the necessity of analyzing the structure of the flows by means of the distribution functions of the residence time in the reactor, which is the basis for the formation of a block of modules of the hydrodynamic level. A change in the length of the reactor cascade leads to a change in the residence time of particles in the reactor and, consequently, to a change in the hydrodynamic regime. With the help of mathematical modeling tools, the influence of the hydrodynamic regime in the reaction zone on the molecular weight distribution of the resulting product is revealed.

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“…In Levkovskaya et al [1] it was shown that, among catalysts based on gadolinium, maximum activity in isoprene polymerisation reactions is possessed by a catalytic complex produced by the interaction of isopropanol solvate of gadolinium chloride and triisobutylaluminium (TIBA). Polymers synthesised in its presence are similar in molecular characteristics (average molecular weights, molecular weight distribution) to 'neodymium' polyisoprenes.…”

mentioning

confidence: 99%

“…A considerable advantage of the 'gadolinium' polymer is its excellent microstructure: the content of cis-1,4-units reaches 98.5-99.0%, while the number of 3,4-units is half that in the 'neodymium' rubber. The differences in microstructure are reflected in a greater proneness of the 'gadolinium' polymers to orientation crystallisation [1], which gives grounds for assuming that their service characteristics are better. Table 1 gives comparative characteristics of polyisoprene specimens synthesised using a catalyst consisting of a solvate of gadolinium chloride (SKI-Gd) and industrial rubber SKI-5PM produced with a neodymium catalyst.…”

mentioning

confidence: 99%

The Physicomechanical Characteristics of Polyisoprene Produced Using a Catalyst Based on Gadolinium Chloride Solvate

Levkovskaya

Васильев

Bubnova

et al. 2016

International Polymer Science and Technology

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It is shown that polyisoprene synthesised in the presence of a catalyst based on an alcohol solvate of gadolinium chloride is similar in molecular characteristics to ‘neodymium’ polyisoprene produced using a similar catalyst. A considerable advantage of the ‘gadolinium’ polymer is the high homogeneity of its microstructure. Specimens of ‘gadolinium’ polyisoprene were synthesised in the Mooney viscosity range 60-90, characterised by the complete absence of gel fraction, in which the content of cis-1,4-units amounts to 98.7-99.1%. The physicomechanical properties of the ‘gadolinium’ polyisoprene were investigated. These properties were compared with the properties of a ‘neodymium’ isoprene rubber (industrial SKI-5PM rubber). It was established that the more regular microstructure of the ‘gadolinium’ polyisoprene by comparison with the ‘neodymium’ polyisoprene is manifested by higher strength and dynamic indices of the rubbers. The resistance to repeated elongation for industrial specimen SKI-5PM with a Mooney viscosity of 78.8 approaches 81 000 cycles, whereas for the ‘gadolinium’ specimen with a similar Mooney viscosity this index reaches 94 000 cycles, and for the ‘gadolinium’ polymer with a Mooney viscosity of 85 and 90 the resistance to repeated elongation exceeds 100 000 cycles. Advantages of the ‘gadolinium’ polyisoprene in terms of tear strength, nominal tensile stress, etc., are also noted.

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Isoprene Polymerisation in the Presence of Catalytic Systems based on Gadolinium Compounds

Cited by 5 publications

References 3 publications

Comparative ONIOM modeling of 1,3‐butadiene polymerization using Nd(III) and Gd(III) Ziegler–Natta catalyst systems

Comparative ONIOM modeling of 1,3‐butadiene polymerization using Nd(III) and Gd(III) Ziegler–Natta catalyst systems

Assessing the Hydrodynamic Effect on the Molecular Parameters of the Isoprene Polymerization Product in the Presence of a Neodymium-Based Catalytic System

The Physicomechanical Characteristics of Polyisoprene Produced Using a Catalyst Based on Gadolinium Chloride Solvate

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