Isospecific Polymerization of Olefins: With Heterogeneous Ziegler-Natta Catalysts

ISBN-13: 9781461295563 / Angielski / Miękka / 2011 / 439 str.

Y. V. Kissin

Opis

The discoveries of organometallic catalysts for olefin polymerization by Karl Ziegler and that of stereoregular olefin polymers by Giulio Natta are probably the two most important achievements in the areas of catalysis and polymer chemistry in the second half of this century. They led to the development of a new branch of chemical industry, and to a large volume production of high-density and linear low-density polyethylene, isotactic polypropylene, ethylene-propylene rubbers, isotactic poly I-butene, and poly-4-methyl-l-pentene. These discoveries merited the Nobel prize, which was awarded to K. Ziegler and G. Natta in 1963. The initial works of Ziegler and Natta were followed by an "explosion" of scientific papers and patents covering all aspects of polymerization chemistry, catalyst synthesis, and polymerization kinetics as well as the structural, chemical, physical, and technological characteristics of stereo regular polyolefins, polydienes, and olefin copolymers. It is sufficient to say that in the twenty-five years after the first publications more than 15,000 papers and patents appeared on subjects related to the area. . The development brought about the establishment of several prominent groups of scientists occupied with the study of olefin polymerization. The most important of these were scientific schools in Italy, Germany, England, the United States, Japan, the Soviet Union, Czechoslovakia, and Venezuela. In addition, many major chemical and petrochemical corporations throughout the world established labora tories devoted to the development of the technology of catalyst synthesis and olefin polymerization."

Spis treści

I Kinetics of Olefin Polymerization with Heterogeneous Ziegler-Natta Catalysts.- I-1 Polymerization Kinetics: General Description.- I-2 Phenomenological Kinetic Scheme of Olefin Polymerization.- I-2-a Stationary Polymerization Process.- I-2-b Initial Acceleration Stage of the Polymerization Process.- I-2-c General Scheme of Olefin Polymerization.- I-3 Molecular Weight Growth in the Beginning of a Polymerization Reaction and the Estimation of the Propagation Rate Constants.- I-3-a General Description.- I-3-b Important Particular Cases.- I-3-c Mean Lifetime of a Polymer Chain.- I-3-d Olefin Block-Copolymers.- I-4 Estimation of Propagation Rate Constants from the Kinetics of Consecutive and Statistical Olefin Copolymerization.- I-4-a Consecutive Copolymerization.- I-4-b Statistical Copolymerization.- I-5 Principal Kinetic Parameters for Olefin Homopolymerization and Copolymerization.- I-5-a Propagation Rate Constants of Olefin Polymerization: Comparison with Other Polymerization Reactions.- I-5-b Monomer Reactivity in Isospecific Polymerization and Its Correlation with Olefin Structural Features.- II Heterogeneous Ziegler-Natta Catalysts: Chemistry and Kinetics of the Formation and Functioning of Active Centers.- II-1 Structure of Solid Components of Ziegler-Natta Catalysts.- II-1-a Crystal Structure.- II-1-b Catalyst Grinding.- II-1-c Structure of Supported Ziegler-NauuCatalysts.- II-2 Formation of Active Center of Heterogeneous Ziegler-Natta Catalysts.- II-2-a Interaction between Catalysts and Co-catalysts in the Gas Phase.- II-2-b Interaction between Catalysts and Co-catalysts in Hydrocarbon Suspension.- II-3 Attempts to Study Active Centers Directly.- II-4 Organometallic Compounds and Catalyst Activity.- II-4-a Organometallic Compounds and Center Formation.- II-4-b Destruction of Active Centers by Organometallic Compounds.- II-4-c Organometallic Compounds as Impurity Scavengers.- II-4-d Organometallic Compounds and the Number and Activity of Polymerization Centers.- II-4-e Polymerization with Various Organometallic Compounds and Their Mixtures.- II-5 Effects of Catalyst Poisons and Modifiers. The Measurement of Active Center Concentration 153.- II-5-a Water 154.- II-5-b Alcohols 159.- II-5-c Measurement of Active Center Concentration Based on Alcohol Reactions.- II-5-d Inorganic Poisons Interacting with Organometallic Compounds.- II-5-e Organic Esters, Ketones, and Ethers.- II-5-f Amines.- II-5-g Modification of TiCl3-AlEtCl2 Systems.- II-5-h Poisons Mainly Affecting Active Centers.- II-6 Concentration of Active Centers and Their Location in the Heterogeneous Catalysts.- II-6-a Concentration of Active Centers.- II-6-b Location of Active Centers on the Catalyst Surface.- II-6-c Activity of Different Modifications of TiCl3.- II-7 Origins of Catalyst Instability.- II-8 Monomer Coordination Stage: Its Chemical and Kinetic Manifestations.- III Stereospecificity of Heterogeneous Ziegler-Natta Catalysts.- III-1 Chemistry of Olefin Polymerization.- III-1-a Normal Reaction Pattern.- III-1-b Monomer Unit Inversion.- III-1-c Monomer Isomerization.- III-2 Methods of Measurement of polyolefin Stereoregularity.- III-2-a Nuclear Magnetic Resonance. Sequence Classification.- III-2-b Infrared Spectroscopy.- III-2-c Melting Point and Polyolefin Stereoregularity.- III-3 Enantiomorphous Statistical Model of Stereospecific Olefin and its Experimental Polymerization Proof.- III-4 Statistics of Olefin Homopolymerization and Copolymerization on Stereospecific Active Centers.- III-4-a Homopolymerization.- III-4-b Copolymerization.- III-5 Parameters Characterizing the Stereo regulative Ability of Active Centers.- III-6 Effect of Transition Metal Compounds on Catalyst Stereo specificity.- III-7 Effect of Organometallic Compounds on Catalyst Stereospecificity.- III-8 Temperature Effect on Catalyst Stereo specificity and the Reaction Pathway of the Propagation Step.- III-9 Role of Catalyst Modification.- III-9-a Catalyst Grinding.- III-9-b Organic Promoters.- III-9-c Inorganic Promoters.- III-9-d Supported Ziegler-Natta Catalysts.- III-10 Stereoregularity and Stereoelective Polymerization.- III-11 Stereoregularity of Monomer Sequences in Olefin Copolymers.- IV Inhomogeneity of Active Centers of Heterogeneous Ziegler Natta Catalysts.- IV-1 Distribution of Active Centers with Different Stereospecificity.- IV-1-a Existence and Models of Continuous Distribution.- IV-1-b Effect of Poisoning on Distribution of Active Center Stereospecificities.- IV-2 Molecular Weight Distribution of Polyolefins and the Distribution of Propagation Rate Constants.- IV-2-a Explanations for the Wide Molecular Weight Distributions of Polyolefins.- IV-2-b MWDs of Polypropylene Obtained at Low Temperature.- IV-3 Compositional Inhomogeneity of Olefin Copolymers and Active Center Distribution with Respect to Reactivity.- V Mechanism of Isospecific Olefin Polymerization.- V-1 Chemical Mechanism of Olefin Polymerization: Olefin Insertion Reaction into the ?-Metal-Bond.- V-2 Intimate Mechanism of the Olefin Insertion Reaction.- V-2-a Olefin Coordination.- V-2-b Geometry of Olefin Coordination.- V-2-c Lability of the Transition Metal-Carbon Bond and the Insertion of Coordinated Olefin into it.- V-2-d Participation of Organometallic Compounds in the Polymerization Center.- V-2-e Cis-Insertion Reaction.- V-3 Molecular Orbital Calculations of the Propagation Step.- V-3-a Earlier Semi-empirical Calculations of the RTiCl4.Center.- V-3-b Hexa- vs. Pentacoordinated Centers: Calculations by CNDO Methods.- V-3-c Ab Initio Calculations of the Center Pentacoordinated.- V-3-d Molecular Orbital Calculations of a Center in u Crystal Lattice.- V-3-e Mechanism of Acetylene Polymerization.- V-4 Mechanism of Isospecific Chain Growth.- V-4-a Experimental Data on Isospecific Chain Propagation.- V-4-b Proposed Models of Isospecific Polymerization Centers.- V-5 Concluding Remarks on the Polymerization Mechanism.