Kinetic Modeling of 1-Hexene Polymerization Catalyzed by Zr(tBu-ONNMe2O)Bn2/B(C6F5)3
| Autor: | Jeffrey M. Switzer, James M. Caruthers, Nicholas E. Travia, W. Nicholas Delgass, Mahdi M. Abu-Omar, D. Keith Steelman, Grigori A. Medvedev, Kendall T. Thomson |
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| Rok vydání: | 2012 |
| Předmět: |
education.field_of_study
Polymers and Plastics Organic Chemistry Population Chain transfer Catalysis Inorganic Chemistry End-group chemistry.chemical_compound Monomer Reaction rate constant Polymerization chemistry Polymer chemistry Materials Chemistry Physical chemistry Molar mass distribution education |
| Zdroj: | Macromolecules. 45:4978-4988 |
| ISSN: | 1520-5835 0024-9297 |
| Popis: | Kinetic modeling using a population balance approach has been performed in order to identify a mechanism and a set of rate constants that describe the batch polymerization of 1-hexene by the homogeneous single-site catalyst Zr(tBu-ONNMe2O)Bn2 activated by B(C6F5)3 in toluene. The mechanism and rate constants were determined by making use of a multiresponse data set, including (i) monomer concentration versus time for various initial concentrations of monomer and catalyst, (ii) the time evolution of the molecular weight distribution, (iii) active site concentrations versus time, and (iv) vinyl end group concentrations versus time. The overall mechanism requires slow chain initiation compared to propagation, 2,1-misinsertion and recovery, and two chain transfer pathways—one forming vinylidene end groups and the other forming vinylene end groups. The quantitative analysis of kinetic data clearly shows that a significant fraction of the catalyst does not participate in the chain growth process. The quantitati... |
| Databáze: | OpenAIRE |
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