TY - JOUR
T1 - A DFT study on the effect of hydrogen in ethylene and propylene polymerization using a Ti-based heterogeneous Ziegler–Natta catalyst
AU - Bahri-Laleh, Naeimeh
AU - Nekoomanesh-Haghighi, Mehdi
AU - Mirmohammadi, Seyed Amin
N1 - KAUST Repository Item: Exported on 2020-10-01
Acknowledgements: The authors thank MOLNAK (www.molnac.unisa.it) for its computer facilities. NBL thanks professor Luigi Cavallo (University of Salerno and King Abdullah University of Science and Technology) for his scientific support.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.
PY - 2012/11
Y1 - 2012/11
N2 - Hydrogenolysis of a series of model Ziegler-Natta (Z-N) catalysts to form Ti-H bond was studied within DFT. We focused our efforts on Ti species attached to the (110) lateral cut of MgCl 2 which exist as different centres including Ti-C 2H 5, Ti-CH 2CH(CH 3) 2, and Ti-CH(CH 3)CH 2CH 3 in ethylene and propylene polymerization. In the next step, reactivity of Ti-H bond towards ethylene and propylene (1,2- and 2,1-) insertion was investigated. Results showed that insertion of ethylene and propylene into Ti-H bond has less barrier, in comparison with their insertion in Ti-C bond, however, ethylene and propylene 2,1- insertion lead to Ti-C 2H 5 and Ti-CH(CH 3) 2 centres respectively, which were stable due to strong β-agostic interactions. Finally, by considering different possible reactions of active centre, activity depression in ethylene polymerization and activity increase in propylene polymerization were explained in detail. © 2012 Elsevier B.V.
AB - Hydrogenolysis of a series of model Ziegler-Natta (Z-N) catalysts to form Ti-H bond was studied within DFT. We focused our efforts on Ti species attached to the (110) lateral cut of MgCl 2 which exist as different centres including Ti-C 2H 5, Ti-CH 2CH(CH 3) 2, and Ti-CH(CH 3)CH 2CH 3 in ethylene and propylene polymerization. In the next step, reactivity of Ti-H bond towards ethylene and propylene (1,2- and 2,1-) insertion was investigated. Results showed that insertion of ethylene and propylene into Ti-H bond has less barrier, in comparison with their insertion in Ti-C bond, however, ethylene and propylene 2,1- insertion lead to Ti-C 2H 5 and Ti-CH(CH 3) 2 centres respectively, which were stable due to strong β-agostic interactions. Finally, by considering different possible reactions of active centre, activity depression in ethylene polymerization and activity increase in propylene polymerization were explained in detail. © 2012 Elsevier B.V.
UR - http://hdl.handle.net/10754/597253
UR - https://linkinghub.elsevier.com/retrieve/pii/S0022328X1200513X
UR - http://www.scopus.com/inward/record.url?scp=84866556458&partnerID=8YFLogxK
U2 - 10.1016/j.jorganchem.2012.08.017
DO - 10.1016/j.jorganchem.2012.08.017
M3 - Article
SN - 0022-328X
VL - 719
SP - 74
EP - 79
JO - Journal of Organometallic Chemistry
JF - Journal of Organometallic Chemistry
ER -