Polymerization of butadiene under the action of lithium containing initiating system

Akhmetov, I.G.; Burganov, R. T.

doi:10.1134/s1070427212050274

Cited by 1 publication

(1 citation statement)

References 15 publications

(19 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Therefore, a significant number of studies have been carried out from the discovery of Ziegler–Natta catalytic systems, which were aimed at increasing the activity and stereospecificity of these catalytic systems by modifying their structure. As a result, catalytic systems, which are complexes of titanium, nickel, cobalt, and neodymium, were selected for the synthesis of polybutadiene. ,,− Among this series of catalytic systems, neodymium-based catalytic systems stand out favorably. They are used in industry in the synthesis of polybutadiene and polyisoprene due to their excellent stereospecificity and high activity. − Neodymium catalytic systems make it possible to obtain polybutadiene containing cis -1,4-butadiene units (up to 98%) .…”

Section: Introductionmentioning

confidence: 99%

Analysis of the Mechanism of Polybutadiene Synthesis in the Presence of the Neodymium Versatate + Diisobutylaluminum Hydride + Ethylaluminum Sesquichloride Catalytic System within the Solution of the Inverse Kinetic Problem

Tereshchenko

Ulitin

Bedrina

et al. 2022

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

A kinetic model is proposed for polybutadiene synthesis in the presence of the neodymium versatate + diisobutylaluminum hydride + ethylaluminum sesquichloride (NdV + DIBAH + EASC) catalytic system. As a result of solving the inverse kinetic problem, the rate coefficients of reactions were determined. At a quantitative level, it has been shown that polybutadiene synthesis in the presence of the NdV + DIBAH + EASC catalytic system can run according to the scheme, which includes only the chain propagation, chain termination, chain transfer to butadiene, and DIBAH. This fact testifies against the need to involve the reactions of the coordinative chain transfer polymerization mechanism to describe the kinetic regularities of the process in question. Based on the bimodal form of the experimental molar mass distributions of polybutadiene, it was taken into account in the proposed kinetic model that all reactions run on active sites of two types. As a result of the calculation of the characteristic times of chain limitation (in which the chain limitation is a sum of chain termination and transfer rates) on active sites of the first and second types, it was shown that the active sites of the first type are the active sites of classical coordination polymerization (the characteristic time of chain limitation is 3.35 × 10 1 −8.82 × 10 1 s) and on active sites of the second type, living chain propagation runs. This is due to the fact that the characteristic chain limitation time for active sites of the second type is 9.09 × 10 3 to 1.35 × 10 5 s, which is comparable to the time of polybutadiene synthesis until a high butadiene conversion is reached (1.00 × 10 4 s).

show abstract