Über die Wirkungsweise metallorganischer Katalysatoren

Sinn, Hansjörg; Patat, F.

doi:10.1002/ange.19630751802

Cited by 80 publications

(10 citation statements)

References 16 publications

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“…The errors measured by 13 C-NMR spectroscopy are randomly distributed along the polymer chain; while in polypropylene made with Ziegler-Natta catalysts, the errors are concentrated at chain ends and in oligomers. The former is called isoblock-polypropylene and is characterized by a lower melting point but higher film transparency.…”

Section: Isotactic Polypropylenementioning

confidence: 99%

The discovery of metallocene catalysts and their present state of the art

Kaminsky

2004

J. Polym. Sci. A Polym. Chem.

361

221

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Metallocene and other transition metal complexes activated by methylaluminoxane are highly active catalysts for the polymerization of olefins, diolefins, and styrene, which was discovered at the University of Hamburg about 25 years ago. These catalysts allow the synthesis of polymers with a highly defined microstructure, tacticity, and stereoregularity, as well as new copolymers with superior properties such as film clarity, tensile strength, and lower extractables. A better understanding of the mechanism of olefin polymerization leads to findings of other new single site catalysts. The development of the metallocene/MAO-catalysts from their discovery to their present state of the art is presented. Keywords:metallocene catalysts; methylaluminoxane; olefin polymerization; zirconocene complexes; polyolefins; single site catalysis Dr. Kaminsky received his Ph.D. and degree in chemistry from Hamburg University, Germany in 1971 for investigating the side reactions of biscyclopentadienyl-zirconiumdichloride and triethylaluminum. He then served as lecturer and continued his research on the determination of zirconocene/aluminumalkyl-complexes and recycling of polymers by pyrolysis in a fluidized bed process. During that time he and Hansjörg Sinn discovered that the activity of metallocenes and other transition metals can be increased extremely by the addition of MAO as a cocatalyst. In 1979 he became full professor at the University of Hamburg for Technical and Macromolecular Chemistry and has served as director, dean, and president of German chemical society, Hamburg section. Dr. Kaminsky has received the following honors and rewards: elected to the

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Section: Isotactic Polypropylenementioning

confidence: 99%

The discovery of metallocene catalysts and their present state of the art

Kaminsky

2004

J. Polym. Sci. A Polym. Chem.

361

221

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“…Metallocenes and other single site catalysts give the possibility to tailor the structure of polymers in a way which has not been achieved before 2–4. Additionally, they offer a detailed understanding of the mechanism and the stereochemistry of the polymerization of olefins 5–14. Classical Ziegler catalysts are heterogeneous with the polymerization taking place on dislocations and edges of the surface of TiCl 3 or on solid mixtures of MgCl 2 /TiCl 4 .…”

Section: Introductionmentioning

confidence: 99%

Comparison of Olefin Polymerization Processes with Metallocene Catalysts

Kaminsky

Müller

Sperber

2005

Macro Materials & Eng

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Summary: Solution and gas phase processes of the polymerization of ethene are compared using new types of pentalenyl bridged ansa‐metallocenes such as [Me3Pen(Flu)]ZrCl2. As of the bridge, the catalyst system is remarkable thermostable up to 105 °C and a deactivation of the metallocene on the silica support can be suppressed. Compared to the non‐supported catalyst in a solution process, the application of the heterogenized system in a gas phase process leads to a decrease in activities while molar masses of the polyethenes are similar. Due to a higher degree of short chain branches of 20–30 per 1 000 carbon atoms instead of 10–17, the melting temperatures are 10 °C lower than those for polymers obtained in the solution process.Basic structure of the here used pentalenyl bridged ansa‐metallocenes.magnified imageBasic structure of the here used pentalenyl bridged ansa‐metallocenes.

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“…Wir beschränken uns auf einige Hinweise zur Herstellung und Anwendung von lithiumorganischen Verbindungen und verweisen den interessierten Leser auf Bücher [7], Übersichtsartikel [8] und einige Originalarbeiten. Das Interesse an lithiumorganischen Verbindungen, vor allem als Synthesebausteine in der gesamten Chemie, hat in jüngster Zeit so zugenommen, dass man ein mehrbändiges Werk darüber herausgeben könnte.…”

Section: Lithiumorganische Verbindungenunclassified

Lithium und seine Verbindungen ‐ Industrielle, medizinische und wissenschaftliche Bedeutung

Deberitz

Boche

2003

Chemie in nserer Zeit

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Der Aufsatz bietet eine kurze Zusammenfassung über die industrielle, medizinische und wissenschaftliche Bedeutung von Lithium und seinen Verbindungen. So ist Lithiumcarbonat von großer Wichtigkeit bei der Glas‐, Email‐ und Keramikherstellung; verschiedene anorganische Lithiumverbindungen dienen als Zementverfestiger, und Lithium‐Fette, d. h. Schmieröle mit Lithiumsalzen von langkettigen aliphatischen Carbonsäuren, sind aus der modernen Technik genauso wenig wegzudenken, wie LiOH als CO2‐Fänger, LiCl (LiF) in der Aluminiumverarbeitung und gewinnung oder LiBr (LiCl) in Kühlanlagen. Bei der Behandlung manisch‐depressiver Erkrankungen haben sich Lithium‐Salze einen festen Platz gesichert. Metallisches Lithium findet zunehmend Anwendung in Batterien. Dass es ohne 6 Lithium keine Wasserstoffbombe gäbe, ist auch nicht allgemein bekannt. Ein Abfallprodukt: der billige Zugang zu 6 Lithium und die daraus entwickelte 6 Li‐NMR‐Spektroskopie. Schließlich einige Hinweise auf Lithium‐organische Verbindungen und ihre große Bedeutung in der modernen (organischen) Synthese, sowohl in Labors als auch in der Technik (z.B. anionische Polymerisation). Ein besonders wichtiges Kapitel stellt die stereoselektive Synthese mit Hilfe von Lithium‐organischen Verbindungen dar.

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Über die Wirkungsweise metallorganischer Katalysatoren

Abstract: KARL WINNACKERz u m 6 0 . G e b u r t s t a g a m 21. S e p t e m b e r 1 9 6 3 g e w i d m e t

Cited by 80 publications

References 16 publications

The discovery of metallocene catalysts and their present state of the art

The discovery of metallocene catalysts and their present state of the art

Comparison of Olefin Polymerization Processes with Metallocene Catalysts

Lithium und seine Verbindungen ‐ Industrielle, medizinische und wissenschaftliche Bedeutung

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