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ZIEGLER-NATTA CATALYST PRESENTED BY: LISAMONI KALITA M.SC 2ND SEM ID: BS14MC0229 DEPT. OF CHEMISTRY ASSAM KAZIRANGA UNIVERSITY 1

Ziegler natta catalyst

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ZIEGLER-NATTA CATALYST

ZIEGLER-NATTA CATALYSTPresented By:Lisamoni KalitaM.Sc 2nd semID: BS14MC0229Dept. of chemistryAssam kaziranga university

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Table of ContentsIntroductionBrief History of Ziegler Natta CatalystMechanism of Ziegler Natta PolymerizationImportance of Ziegler Natta CatalystApplications of Ziegler Natta CatalystConclusionReference2

IntroductionKarl Ziegler in 1953 polymerized ethylene catalytically to polyethylene.Giulio Natta utilized Ziegler's catalyst to produce polypropylene in 1954.In 1963, both Karl Ziegler and Giulio Natta were awarded the Nobel Prize for their discoveries.In 1973 the 2nd generation Ziegler-Natta catalysts were introduced with -TiCl3 at lower temperatures.In 1980 3rd generation catalysts supported on MgCl2 were commercialized by many companies.In 1991 4th generation Ziegler-Natta catalysts based on aluminoxane activated metallocene complexes were used.Two broad classes: Heterogeneous Catalyst: Based on Ti compoundsHomogeneous Catalyst: Based on complexes of Ti, Zr and Hf

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Zieglers Discovery (Germany,1953)

4Co-catalystcatalystKarl Ziegler-the last Al-Chemist ...because he turned aluminium into gold.

Nattas Discovery (Italy,1954)

5isotacticsyndiotactic

Mechanism of Ziegler-Natta Polymerization: The Cossee Mechanism6

Catalyst acceptsethylene as a ligand1,2- Migratory insertion [Ethyl migration]

Termination Step: Chain Transfer

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Kaminsky Catalyst System8M = Ti, Zr, HfLinearAtactic polypropylene

MAOMAOMAO=methylaluminoxaneHomogeneous Ziegler Natta Catalyst

Brintzinger System9Brintzinger developed these catalysts which when activated with MAO catalysed the stereoselective polymerizations of propylene with very high activities. Thus for the first time isotactic polyolefins were obtained using homogeneous Ziegler-Natta catalyst

R= CH3, C2H5X= Cl, Br, CH3M= Ti, Zr

Importance of Ziegler Natta CatalystHigh SelectivityHigh EfficiencyHigh Stereoregularity (99% tacticity)Longer LifetimeHigh concentration of polymer productLower cost in productionEasy regeneration of catalystControls growth and formation of polymer productControl of polymer particle morphology in spherical shapeHigher stability

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Example:Propene can polymerize in three ways:

TiCl4 + Al(C2H5)311

Highly selective towards isotactic productHighly stable product

AtacticIsotacticSyndiotacticMgCl2

Applications of Ziegler-Natta CatalystProduction of: High density polyethylene (HDPE)Linear low density polyethylene (LDPE)Ultra-high molecular weight polyethylene (UHMWPE)Thermoplastic polyolefins (TPOs)Polybutylene (PB)Shiny lustrous polyacetylene film which have semiconducting propertiesCrystalline polypropyleneCarbon nanotubes nanocomposites12

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ConclusionZiegler Natta are mainly used to polymerize 1-alkenes.

Ziegler Natta catalyst is composed of a catalyst and co-catalyst.

Ziegler-Natta catalysts can be categorized into heterogeneous and homogenous by their form in catalysis process. The heterogeneous one is widely used in industry.

Only Ziegler-Natta catalysts can produce highly stereoregular and linear unbranched polyolefins.

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ReferencesPokasermsong P. and Praserthdam P.; Comparison of Activity Of Ziegler-Natta Catalysts; Engineering Journal; Vol. 13; 2009; 57Ahmad A.; Propylene Polymerization Using 4th Generation Ziegler-Natta Catalysts: Polymerization Kinetics and Polymer Microstructural Investigation; A thesis presented to the University of Waterloo; 2011Cerruti L.; Historical and Philosophical Remarks on Ziegler-Natta Catalysts; HYLE An International Journal for the Philosophy of Chemistry; Vol. 5; 1999; 3.Bajgur C. S. and Sivaram S.; The evolution of new generation single-site ZieglerNatta polymerization catalysts; Current Science; Vol. 78; 2000; 1325Busico V., Cipullo R., Pellecchia R., Ronca S., Roviello G., and Talarico G.; Design of stereoselective ZieglerNatta propene polymerization catalysts; PNAS; vol. 103; 2006; 15321

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References Contd.Lewin M.; Handbook of Fiber Chemistry; CRC Press; Third Edition; ISBN 1420015273Gross E., Liu J. H, Toste F. D. and Somorjai G. A.; Control of selectivity in heterogeneous catalysis by tuning nanoparticle properties and reactor residence time; Nature Chemistry ; Vol. 4; 2012; 947Clayden J., Greeves N. and Warren S.; Organic Chemistry; Oxford; Second Edition; ISBN 978-0-19-927029-3Gupta B. D., Elias A. J.; Basic Organometallic Chemistry Concepts, Syntheses and Applications; University Press; Second Edition; ISBN 978-81-7371-874-8Ramakrishnan S; Conducting Polymers; RESONANCE ; Vol.2; 2011; 48http://en.wikipedia.org/wiki/Ziegler%E2%93Natta_catalysthttp://www.chemheritage.org/discover/online-resources/chemistry-in-history/themes/petrochemistry-and-synthetic-polymers/ziegler-and-natta.aspx

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Thank you17