{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:33:50Z","timestamp":1760060030212,"version":"build-2065373602"},"reference-count":48,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2025,8,1]],"date-time":"2025-08-01T00:00:00Z","timestamp":1754006400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Computation"],"abstract":"<jats:p>Divinylisoprene rubber, a copolymer of butadiene and isoprene, is used as raw material for rubber technical products, combining isoprene rubber\u2019s elasticity and butadiene rubber\u2019s wear resistance. These properties depend quantitatively on the copolymer composition, which depends on the kinetics of its synthesis. This work aims to theoretically describe how the monomer mixture composition in the butadiene\u2013isoprene copolymerization affects the activity of the TiCl4-Al(i-C4H9)3 catalytic system (expressed by active sites concentration) via kinetic modeling. This enables development of a reliable kinetic model for divinylisoprene rubber synthesis, predicting reaction rate, molecular weight, and composition, applicable to reactor design and process intensification. Active sites concentrations were calculated from experimental copolymerization rates and known chain propagation constants for various monomer compositions. Kinetic equations for active sites formation were based on mass-action law and Langmuir monomolecular adsorption theory. An analytical equation relating active sites concentration to monomer composition was derived, analyzed, and optimized with experimental data. The results show that monomer composition\u2019s influence on active sites concentration is well described by a two-step kinetic model (physical adsorption followed by Ti\u2013C bond formation), accounting for competitive adsorption: isoprene adsorbs more readily, while butadiene forms more stable active sites.<\/jats:p>","DOI":"10.3390\/computation13080184","type":"journal-article","created":{"date-parts":[[2025,8,4]],"date-time":"2025-08-04T10:48:08Z","timestamp":1754304488000},"page":"184","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Effect of Monomer Mixture Composition on TiCl4-Al(i-C4H9)3 Catalytic System Activity in Butadiene\u2013Isoprene Copolymerization: A Theoretical Study"],"prefix":"10.3390","volume":"13","author":[{"given":"Konstantin A.","family":"Tereshchenko","sequence":"first","affiliation":[{"name":"Department of General Chemical Technology, Kazan National Research Technological University, 420015 Kazan, Russia"}]},{"given":"Rustem T.","family":"Ismagilov","sequence":"additional","affiliation":[{"name":"Department of General Chemical Technology, Kazan National Research Technological University, 420015 Kazan, Russia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6126-9941","authenticated-orcid":false,"given":"Nikolai V.","family":"Ulitin","sequence":"additional","affiliation":[{"name":"Department of General Chemical Technology, Kazan National Research Technological University, 420015 Kazan, Russia"}]},{"given":"Yana L.","family":"Lyulinskaya","sequence":"additional","affiliation":[{"name":"Department of General Chemical Technology, Kazan National Research Technological University, 420015 Kazan, Russia"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9913-5324","authenticated-orcid":false,"given":"Alexander S.","family":"Novikov","sequence":"additional","affiliation":[{"name":"Department of Physical Organic Chemistry, Institute of Chemistry, Saint Petersburg State University, 199034 Saint Petersburg, Russia"},{"name":"Scientific Center of Crystal Chemistry and Structural Analysis, Research Institute of Chemistry, Peoples\u2019 Friendship University of Russia (RUDN University), 117198 Moscow, Russia"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,1]]},"reference":[{"unstructured":"Bhatia, S., and Goel, A. 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