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Hernández-Fernández J, Puello-Polo E, Marquez E. Study of the Chemical Activities of Carbon Monoxide, Carbon Dioxide, and Oxygen Traces as Critical Inhibitors of Polypropylene Synthesis. Polymers (Basel) 2024; 16:605. [PMID: 38475289 DOI: 10.3390/polym16050605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 10/01/2023] [Accepted: 10/04/2023] [Indexed: 03/14/2024] Open
Abstract
This study outlines the investigation into how the compounds CO2, CO, and O2 interact with the active center of titanium (Ti) on the surface of MgCl2 and how these interactions impact the productivity of the Ziegler-Natta catalyst, ultimately influencing the thermal stability of the produced polypropylene. The calculations revealed that the adsorption energies of Ti-CO2-CO and O2 were -9.6, -12.5, and -2.32 Kcal/mol, respectively. Using the density functional theory in quantum calculations, the impacts of electronic properties and molecular structure on the adsorption of CO, O2, and CO2 on the Ziegler-Natta catalyst were thoroughly explored. Additionally, the Gibbs free energy and enthalpy of adsorption were examined. It was discovered that strong adsorption and a significant energy release (-16.2 kcal/mol) during CO adsorption could explain why this gas caused the most substantial reductions in the ZN catalyst productivity. These findings are supported by experimental tests showing that carbon monoxide has the most significant impact on the ZN catalyst productivity, followed by carbon dioxide, while oxygen exerts a less pronounced inhibitory effect.
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Affiliation(s)
- Joaquín Hernández-Fernández
- Chemistry Program, Department of Natural and Exact Sciences, University of Cartagena, San Pablo Campus, Cartagena 130015, Colombia
- Chemical Engineering Program, School of Engineering, Universidad Tecnológica de Bolivar, Parque Industrial y Tecnológico Carlos Vélez Pombo Km 1 Vía Turbaco, Cartagena 130001, Colombia
- Department of Natural and Exact Science, Universidad de la Costa, Barranquilla 080002, Colombia
| | - Esneyder Puello-Polo
- Group de Investigación en Oxi/Hidrotratamiento Catalítico Y Nuevos Materiales, Programa de Química-Ciencias Básicas, Universidad del Atlántico, Puerto Colombia 081001, Colombia
| | - Edgar Marquez
- Grupo de Investigaciones en Química Y Biología, Departamento de Química Y Biología, Facultad de Ciencias Básicas, Universidad del Norte, Carrera 51B, Km 5, Vía Puerto Colombia, Barranquilla 081007, Colombia
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Ali A, Naveed A, Maroń A, Younis MA, Moradian JM, Yousaf B, Aziz T, Ali RN, Ahmad N, Alomar SY, Zheqiang F, Guo L. Copolymerization of ethylene and isoprene via silicon bridge metallocene [rac-Me 2Si(2-Me-4-Ph-Ind) 2ZrCl 2] catalyst: A new way to control the composition and microstructure of copolymers. CHEMOSPHERE 2024; 347:140700. [PMID: 37977533 DOI: 10.1016/j.chemosphere.2023.140700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 10/03/2023] [Accepted: 11/10/2023] [Indexed: 11/19/2023]
Abstract
The copolymerization of ethylene (E) with isoprene (Ip) was performed catalyzed by a symmetrical catalyst exhibiting a silicon bridge [rac-Me2Si(2-Me-4-Ph-Ind)2ZrCl2 with the combination of borate/TIBA activator. The effect of cocatalyst, Ip concentration, and polymerization temperature on the activity, molecular weight (Mw), distribution (MWD), comonomer composition, chain structure (regio- and stereoselectivity), and resulting side reactions were logically addressed. Gel-permeation chromatography (GPC) was used to characterize the Mw and polydispersity, while nuclear magnetic resonance (NMR) was employed for the chain structure of the polymers. The catalytic activity was significantly lower by increasing the Ip concentration in the feed, and the isoprene content in resulting polymers was lower under the reaction condition, leading to higher activity. Insertion of isoprene units in polymer structure demonstrates the higher regioselectivity for the 3,4 connections than the 1,4 connections and is expected to be a high-resistance polymer against acids. The MWD presented monomodal even with a higher concentration (1.44 mol/L) and did not appear as low Mw peaks of Ip. The Mw was higher with a broader MWD when purely TIBA was used as a cocatalyst, and it significantly reduced and presented a narrowed MWD with TEA in the cocatalyst. The higher efficiency of the catalyst for the higher insertion of Ip (C=C double bond) effectively modifies the polymer backbone. It is expected to be a promising candidate for easily degradable and favorable solutions for solving environmental problems caused by PE. wastes.
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Affiliation(s)
- Amjad Ali
- School of Materials Science & Engineering, Jiangsu University, Zhenjiang, 212013, PR China; Institute of Chemistry, University of Silesia, Szkolna 9, Katowice, 40-600, Poland; MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, PR China
| | - Ahmad Naveed
- School of Materials Science & Engineering, Jiangsu University, Zhenjiang, 212013, PR China.
| | - Anna Maroń
- Institute of Chemistry, University of Silesia, Szkolna 9, Katowice, 40-600, Poland
| | - Muhammad Adnan Younis
- Institute of Microscale Optoelectronics, Shenzhen University, Shenzhen, 518060, PR China
| | | | - Balal Yousaf
- Department of Technologies and Installations for West Management, Faculty of Engineering, Silesian University of Technology, Konarskiego 18, 44-100, Gliwice, Poland
| | - Tariq Aziz
- School of Engineering Yunqi Campus, Westlake University, Hangzhou, Zhejiang, 310024, PR China
| | - Rai Nauman Ali
- Laboratory of Inorganic Materials for Sustainable Energy Technologies, Mohammed IV Polytechnic University, Benguirer, Morocco
| | - Naushad Ahmad
- Department of Chemistry, College of Science, King Saud University, Riyadh, 11451, Kingdom of Saudi Arabia
| | - Suliman Yousef Alomar
- Zoology Department, College of Science, King Saud University, Riyadh, 11451, Kingdom of Saudi Arabia
| | - Fan Zheqiang
- MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou, 310027, PR China
| | - Li Guo
- School of Materials Science & Engineering, Jiangsu University, Zhenjiang, 212013, PR China.
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Hernández-Fernández J, González-Cuello R, Ortega-Toro R. Dimethylformamide Impurities as Propylene Polymerization Inhibitor. Polymers (Basel) 2023; 15:3806. [PMID: 37765660 PMCID: PMC10538092 DOI: 10.3390/polym15183806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Revised: 09/08/2023] [Accepted: 09/11/2023] [Indexed: 09/29/2023] Open
Abstract
This research study examined how the use of dimethylformamide (DMF) as an inhibitor affects the propylene polymerization process when using a Ziegler-Natta catalyst. Several experiments were carried out using TiCl4/MgCl2 as a catalyst, aluminum trialkyl as a cocatalyst, and different amounts of DMF. Then, we analyzed how DMF influences other aspects of the process, such as catalyst activity, molecular weight, and the number of branches in the polymer chains obtained, using experimental and computational methods. The results revealed that as the DMF/Ti ratio increases, the catalyst activity decreases. From a concentration of 5.11 ppm of DMF, a decrease in catalyst activity was observed, ranging from 45 TM/Kg to 44 TM/Kg. When the DMF concentration was increased to 40.23 ppm, the catalyst activity decreased to 43 TM/Kg, and with 75.32 ppm, it dropped even further to 39 TM/Kg. The highest concentration of DMF evaluated, 89.92 ppm, resulted in a catalyst productivity of 36.5 TM/Kg and lost productivity of 22%. In addition, significant changes in the polymer's melt flow index (MFI) were noted as the DMF concentration increased. When 89.92 ppm of DMF was added, the MFI loss was 75%, indicating a higher flowability of the polymer. In this study, it was found that dimethylformamide (DMF) exhibits a strong affinity for the titanium center of a Ziegler-Natta (ZN) catalyst, with an adsorption energy (Ead) of approximately -46.157 kcal/mol, indicating a robust interaction. This affinity is significantly higher compared to propylene, which has an Ead of approximately -5.2 kcal/mol. The study also revealed that the energy gap between the highest occupied molecular orbital (HOMO) of DMF and the lowest unoccupied molecular orbital (SOMO) of the Ziegler-Natta (ZN) catalyst is energetically favorable, with a value of approximately 0.311 eV.
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Affiliation(s)
- Joaquín Hernández-Fernández
- Chemistry Program, Department of Natural and Exact Sciences, San Pablo Campus, University of Cartagena, Cartagena 130015, Colombia
- Chemical Engineering Program, School of Engineering, Universidad Tecnológica de Bolivar, Parque Industrial y Tecnológico Carlos Vélez Pombo, Km 1 Vía Turbaco, Turbaco 130001, Colombia
- Department of Natural and Exact Science, Universidad de la Costa, Barranquilla 30300, Colombia
| | - Rafael González-Cuello
- Food Packaging and Shelf-Life Research Group (FP&SL), Food Engineering Program, Universidad de Cartagena, Avenida del Consulado St. 30, Cartagena de Indias 130015, Colombia; (R.G.-C.); (R.O.-T.)
| | - Rodrigo Ortega-Toro
- Food Packaging and Shelf-Life Research Group (FP&SL), Food Engineering Program, Universidad de Cartagena, Avenida del Consulado St. 30, Cartagena de Indias 130015, Colombia; (R.G.-C.); (R.O.-T.)
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Modified Magnesium Alkyls for Ziegler–Natta Catalysts. Catalysts 2022. [DOI: 10.3390/catal12090973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Magnesium alkyls such as butyl octyl magnesium and butyl ethyl magnesium are used as precursors for highly active and water-free magnesium chloride support materials for Ziegler–Natta catalysts. These alkyls show a high viscosity in hydrocarbon solvents which negatively affect their industrial application. Density functional theory (DFT) calculations supported the hypothesis that magnesium alkyls can form oligomeric chain structures responsible for the high viscosity. Heterocumulenes such as isocyanates, isothiocyanates and carbodiimides were studied as additives reducing the viscosity, supported by DFT calculations. The modified alkyls have further been tested in catalyst synthesis and in the polymerization of ethylene. The polymerization results showed high activities and similar polymer properties compared with a catalyst prepared without modified magnesium alkyl.
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Göpperl L, Pernusch D, Schwarz J, Paulik C. Impact of Polymerization Process Parameters on Improved Comonomer Incorporation Behavior in Ziegler‐Natta Catalysis. MACROMOL REACT ENG 2021. [DOI: 10.1002/mren.202100042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Lukas Göpperl
- Institute for Chemical Technology of Organic Materials Johannes Kepler University Linz Altenbergerstrasse 69 Linz 4040 Austria
| | - Daniel Pernusch
- Institute for Chemical Technology of Organic Materials Johannes Kepler University Linz Altenbergerstrasse 69 Linz 4040 Austria
| | - Julia Schwarz
- Institute for Chemical Technology of Organic Materials Johannes Kepler University Linz Altenbergerstrasse 69 Linz 4040 Austria
| | - Christian Paulik
- Institute for Chemical Technology of Organic Materials Johannes Kepler University Linz Altenbergerstrasse 69 Linz 4040 Austria
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