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Joao B P Soares - One of the best experts on this subject based on the ideXlab platform.
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Polyolefin Reaction Engineering
2012Co-Authors: Joao B P Soares, Timothy F. L. MckennaAbstract:PREFACE INTRODUCTION TO Polyolefins Introduction Polyethylene Resins Polypropylene Resins POLYOLEFIN MICROSTRUCTURAL CHARACTERIZATION Introduction Molecular Weight Distribution Chemical Composition Distribution Cross-Fractionation Techniques Long-Chain Branching POLYMERIZATION CATALYSIS AND MECHANISM Introduction Catalyst Types Supporting Single-Site Catalysts Polymerization Mechanism with Coordination Catalysts POLYOLEFIN REACTORS AND PROCESSES Introduction Reactor Configurations and Design Olefin Polymerization Processes Conclusion POLYMERIZATION KINETICS Introduction Fundamental Model for Polymerization Kinetics Nonstandard Polymerization Kinetics Models Vapor-Liquid-Solid Equilibrium Considerations POLYOLEFIN MICROSTRUCTURAL MODELING Introduction Instantaneous Distributions Monte Carlo Simulation PARTICLE GROWTH AND SINGLE PARTICLE MODELING Introduction Particle Fragmentation and Growth Single Particle Models Limitations of the PFM/MGM Approach: Particle Morphology DEVELOPING MODELS FOR INDUSTRIAL REACTORS Introduction
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Polyolefin Characterization: The First International Conference on Polyolefin Characterization - An Overview of Important Microstructural Distributions for Polyolefin Analysis
Macromolecular Symposia, 2007Co-Authors: Joao B P SoaresAbstract:Polyolefins with complex microstructures are becoming increasingly common in academic and industrial applications. Polyolefin analytical techniques are evolving to provide a more detailed picture of these microstructures, with the development and improvement of hyphenated-techniques and cross-fractionation methods. These modern analytical techniques provide a wealth of information on polyolefin microstructure and, despite being extremely useful, they can also be hard to interpret without the help of mathematical models that link polymerization kinetics to chain microstructure and polymer characterization results. In this paper we review some of the most important distributions for polyolefin microstructure and derive a few new expressions that help understand the results obtained with several polyolefin characterization techniques.
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polymerization reaction engineering metallocene catalysts
Progress in Polymer Science, 1996Co-Authors: Archie E. Hamielec, Joao B P SoaresAbstract:Abstract Metallocene catalysts are operative in all existing industrial plants that are presently used for polyolefin manufacture and have the potential to revolutionize the technology for the production of these polymers. A review of metallocene catalysis and its effects on polymer process engineering for the manufacture of Polyolefins is provided. This review concentrates on the aspects of polymer reactor engineering, mathematical modelling of polymerization processes, and the characterization of Polyolefins made with these novel catalysts.
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Polymerization reaction engineering — Metallocene catalysts
Progress in Polymer Science, 1996Co-Authors: Archie E. Hamielec, Joao B P SoaresAbstract:Abstract Metallocene catalysts are operative in all existing industrial plants that are presently used for polyolefin manufacture and have the potential to revolutionize the technology for the production of these polymers. A review of metallocene catalysis and its effects on polymer process engineering for the manufacture of Polyolefins is provided. This review concentrates on the aspects of polymer reactor engineering, mathematical modelling of polymerization processes, and the characterization of Polyolefins made with these novel catalysts.
Archie E. Hamielec - One of the best experts on this subject based on the ideXlab platform.
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polymerization reaction engineering metallocene catalysts
Progress in Polymer Science, 1996Co-Authors: Archie E. Hamielec, Joao B P SoaresAbstract:Abstract Metallocene catalysts are operative in all existing industrial plants that are presently used for polyolefin manufacture and have the potential to revolutionize the technology for the production of these polymers. A review of metallocene catalysis and its effects on polymer process engineering for the manufacture of Polyolefins is provided. This review concentrates on the aspects of polymer reactor engineering, mathematical modelling of polymerization processes, and the characterization of Polyolefins made with these novel catalysts.
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Polymerization reaction engineering — Metallocene catalysts
Progress in Polymer Science, 1996Co-Authors: Archie E. Hamielec, Joao B P SoaresAbstract:Abstract Metallocene catalysts are operative in all existing industrial plants that are presently used for polyolefin manufacture and have the potential to revolutionize the technology for the production of these polymers. A review of metallocene catalysis and its effects on polymer process engineering for the manufacture of Polyolefins is provided. This review concentrates on the aspects of polymer reactor engineering, mathematical modelling of polymerization processes, and the characterization of Polyolefins made with these novel catalysts.
Luciano Piergiovanni - One of the best experts on this subject based on the ideXlab platform.
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the fundamentals of flame treatment for the surface activation of polyolefin polymers a review
Polymer, 2010Co-Authors: Stefano Farris, Simone Pozzoli, Paolo Biagioni, Stefano Mancinelli, Luciano PiergiovanniAbstract:This paper aims to provide an exhaustive and comprehensive overview on flame treatment as a valuable technique for improving the surface properties of polymers, especially Polyolefins. It starts with a brief historical excursus on the origin of flame treatment, and the second section deals with the major fundamentals of flame chemistry, with a special focus on the combustion process and mechanism of surface activation. The most important parameters influencing the extent of the oxidation reaction along with relevant practical notes are discussed in the third section. The concluding section outlines how the most significant features of flame treatment can be profitably used to improve the wettability and adhesion properties of polyolefin surfaces, especially from the perspective of developing novel composite solutions such as Polyolefins/bio-based coating pairs intended for many different applications.
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The fundamentals of flame treatment for the surface activation of polyolefin polymers – A review
Polymer, 2010Co-Authors: Stefano Farris, Simone Pozzoli, Paolo Biagioni, Stefano Mancinelli, Lamberto Duò, Luciano PiergiovanniAbstract:This paper aims to provide an exhaustive and comprehensive overview on flame treatment as a valuable technique for improving the surface properties of polymers, especially Polyolefins. It starts with a brief historical excursus on the origin of flame treatment, and the second section deals with the major fundamentals of flame chemistry, with a special focus on the combustion process and mechanism of surface activation. The most important parameters influencing the extent of the oxidation reaction along with relevant practical notes are discussed in the third section. The concluding section outlines how the most significant features of flame treatment can be profitably used to improve the wettability and adhesion properties of polyolefin surfaces, especially from the perspective of developing novel composite solutions such as Polyolefins/bio-based coating pairs intended for many different applications.
Matthew Miller - One of the best experts on this subject based on the ideXlab platform.
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separation of Polyolefins based on comonomer content using high temperature gradient adsorption liquid chromatography with a graphitic carbon column
Journal of Applied Polymer Science, 2012Co-Authors: Matthew Miller, John W. Lyons, Freddy Van Damme, Willem A Degroot, Bill WinnifordAbstract:This report describes the application of a recently developed polyolefin characterization tool based upon gradient adsorption high-temperature liquid chromatography (HT-LC) using a graphitic carbon stationary phase to polyolefin homopolymer and previously unreported copolymer systems. Polyolefin-based materials find utility in a broad range of applications and are differentiated by parameters such as molecular weight and comonomer content. Polymer comonomer distribution is commonly determined by crystallinity-based separations (ATREF, CRYSTAF). These techniques, however, are time consuming. In addition, some semicrystalline polymers undergo cocrystallization, impacting the techniques' universal utility. Adsorption-based HT-LC can ideally overcome the limitations of crystallinity-based separations, shedding new light on the composition of randomly-polymerized Polyolefins. In this report the basic separation capability of the adsorption HT-LC technique, using a graphitic carbon column, is demonstrated for poly (ethylene-co-octene) and poly(ethylene-co-propylene) systems and compared with select precipitation/redissolution HT-LC and ATREF results. Select results in this paper are also compared and contrasted to other recent publications on similar separations of Polyolefins. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
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Separation of Polyolefins based on comonomer content using high‐temperature gradient adsorption liquid chromatography with a graphitic carbon column
Journal of Applied Polymer Science, 2011Co-Authors: Matthew Miller, A. Willem Degroot, John W. Lyons, Freddy Van Damme, Bill WinnifordAbstract:This report describes the application of a recently developed polyolefin characterization tool based upon gradient adsorption high-temperature liquid chromatography (HT-LC) using a graphitic carbon stationary phase to polyolefin homopolymer and previously unreported copolymer systems. Polyolefin-based materials find utility in a broad range of applications and are differentiated by parameters such as molecular weight and comonomer content. Polymer comonomer distribution is commonly determined by crystallinity-based separations (ATREF, CRYSTAF). These techniques, however, are time consuming. In addition, some semicrystalline polymers undergo cocrystallization, impacting the techniques' universal utility. Adsorption-based HT-LC can ideally overcome the limitations of crystallinity-based separations, shedding new light on the composition of randomly-polymerized Polyolefins. In this report the basic separation capability of the adsorption HT-LC technique, using a graphitic carbon column, is demonstrated for poly (ethylene-co-octene) and poly(ethylene-co-propylene) systems and compared with select precipitation/redissolution HT-LC and ATREF results. Select results in this paper are also compared and contrasted to other recent publications on similar separations of Polyolefins. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
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a new technique for characterizing comonomer distribution in Polyolefins high temperature thermal gradient interaction chromatography ht tgic
Macromolecules, 2011Co-Authors: Rongjuan Cong, Willem Degroot, Al Parrott, Wallace W Yau, Lonnie G Hazlitt, Ray Brown, Matthew Miller, Zhe ZhouAbstract:This paper documents a new polyolefin characterization technique, high-temperature thermal gradient interaction chromatography (HT-TGIC or TGIC), to quantify comonomer distribution. A set of homogeneous ethylene−octene homopolymers are used with a commercially available column having a graphitic substrate (HYPERCARB) to demonstrate this technique’s applicability to fractionating Polyolefins. The separation mechanism appears to be based on the interaction of the polyolefin chains with the graphite surface upon a temperature change in an isocratic solvent. The TGIC technique overcomes the key issues encountered in crystallization based techniques and in high-temperature liquid chromatography with a solvent gradient (HT-LC). Crystallization based techniques cover only a narrow analysis range of 0−9 mol % comonomer content and suffer from potential error in the analysis caused by cocrystallization effects. HT-LC is limited in its capability because of the limited choice in detectors available. Conversely, TGI...
Masaya Kawasumi - One of the best experts on this subject based on the ideXlab platform.
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development and applications of polyolefin and rubber clay nanocomposites
Polymer Journal, 2011Co-Authors: Makoto Kato, Arimitsu Usuki, Naoki Hasegawa, Hirotaka Okamoto, Masaya KawasumiAbstract:Polyolefins (polypropylene (PP), polyethylene and so on) and polyolefin rubbers (ethylene propylene diene monomer, ethylene propylene elastomer and so on) are the most widely used polymers. Therefore, a development of a polyolefin and polyolefin rubber–clay nanocomposite has been desired for a long time. As these polyolefin polymers do not include any polar groups in its backbone, it was thought that the homogeneous dispersion of the silicate layers would not be realized. But we have successfully developed these polymer–clay nanocomposites by using various methods.
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Development and applications of polyolefin– and rubber–clay nanocomposites
Polymer Journal, 2011Co-Authors: Makoto Kato, Arimitsu Usuki, Naoki Hasegawa, Hirotaka Okamoto, Masaya KawasumiAbstract:Polyolefins (polypropylene (PP), polyethylene and so on) and polyolefin rubbers (ethylene propylene diene monomer, ethylene propylene elastomer and so on) are the most widely used polymers. Therefore, a development of a polyolefin and polyolefin rubber–clay nanocomposite has been desired for a long time. As these polyolefin polymers do not include any polar groups in its backbone, it was thought that the homogeneous dispersion of the silicate layers would not be realized. But we have successfully developed these polymer–clay nanocomposites by using various methods.
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Polyolefin-clay hybrids based on modified Polyolefins and organophilic clay
Macromolecular Materials and Engineering, 2000Co-Authors: Naoki Hasegawa, Makoto Kato, Hirotaka Okamoto, Masaya Kawasumi, Azusa Tsukigase, Arimistu UsukiAbstract:A novel and general approach to prepare polyolefin-clay hybrids by using the maleic anhydride modified Polyolefins and organophilic clay during melt-blending was reported. The silicate layers of the clay were exfoliated and homogeneously dispersed at the monolayers in the hybrids. The hybrids exhibited remarkable reinforcement compared to conventional composites filled with talc which were dispersed at micrometer level.