Catalytic Production of Olefin Block Copolymers via Chain Shuttling Polymerization

Arriola, Daniel J.; Carnahan, Edmund M.; Hustad, Phillip D.; Kuhlman, Roger L.; Wenzel, Timothy T.

doi:10.1126/science.1125268

Cited by 876 publications

(883 citation statements)

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“…The synthesis of a multiblock copolymer through this mechanism is called chain-shuttling polymerization. 73 Ethene-based diblock copolymers were also synthesized by switching the monomer composition during coordinative chain transfer polymerization. 74 The combination of a living polymerization catalyst and a suitable chain transfer reagent should give monodisperse polymers if the propagation rate is much faster than the chain transfer rate and chain transfer occurs only after all the monomer is consumed (Scheme 11).…”

Section: Living Polymerization Of Olefins T Shionomentioning

confidence: 99%

Living polymerization of olefins with ansa-dimethylsilylene(fluorenyl)(amido)dimethyltitanium-based catalysts

Shiono

2011

Polym J

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This article reviews the living homopolymerization and copolymerization of propene, 1-alkene and norbornene with ansadimethysilylene(fluorenyl)(amido)dimethyltitanium, Me 2 Si(g 3 -C 13 H 8 )(g 1 -N t Bu)TiMe 2 and its derivatives, correlating the effects of cocatalysts, solvents, polymerization conditions and the substituents of the fluorenyl ligand with catalytic features, such as livingness, initiation efficiency, propagation rate, syndiospecificity and copolymerization ability. The synthesis of novel olefin block copolymers and their catalytic synthesis are also introduced using this living system. Polymer Journal (2011) 43, 331-351; doi:10.1038/pj.2011 Keywords: cycloolefin copolymer; living polymerization; norbornene; propene; single-site catalyst; syndiospecific polymerization; 1-alkene A living polymerization system, in which neither chain transfer nor deactivation occurs, affords polymers with predictable molecular weights and narrow molecular weight distributions (MWDs). Living polymerization techniques are utilized for the synthesis of terminally functionalized polymers and block copolymers. Another feature of living polymerization is its simple kinetics. Because neither chain transfer nor deactivation occurs in living polymerization, the number of polymer chains (N) is equal to the number of active centers ([C*]), and the number-average molecular weight (M n ) directly reflects the propagation rate. In living polymerization, the propagation rate can be evaluated from the M n value and the polymerization time. As chain transfer via b-elimination and/or transmetalation with trialkylaluminum as a cocatalyst is inevitable in conventional Ziegler-Natta catalytic systems; homogeneous V(acac) 3 /Et 2 AlCl (where acac is acetylacetonate or its analog) had previously been the only catalytic system that produced syndiotactic-rich living polypropylene (PP) atThe development of metallocene catalysts has enabled us to produce a variety of uniform olefin copolymers and to control the stereoregularity of poly(1-alkene)s. 3,4 The success of metallocene catalysts has stimulated research on transition metal complexes for olefin polymerization, 5-7 so-called single-site catalysts, which has also resulted in various transition metal complexes for the living polymerization of olefins. 8,9 We have also developed a living polymerization system using ansa-dimethysilylene(fluorenyl)(amido)dimethyltitanium, Me 2 Si(Z 3 -C 13 H 8 )(Z 1 -N t Bu)TiMe 2 (1), combined with a suitable cocatalyst. The catalytic system allows not only a syndiospecific living polymerization of propene and a 1-alkene but also a living homopolymerization and copolymerization of norbornene with a 1-alkene. We investigated the effect of cocatalyst, solvent and the ligand of the titanium complex on propene polymerization in terms of the livingness of the system. We also synthesized novel olefin block copolymers with the living system. This article reviews the characteristics of 1-based catalysts for tailor-made polyolefins. SYNTHESIS AND STRUCTURES OF TIT...

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Section: Living Polymerization Of Olefins T Shionomentioning

confidence: 99%

Living polymerization of olefins with ansa-dimethylsilylene(fluorenyl)(amido)dimethyltitanium-based catalysts

Shiono

2011

Polym J

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“…Significant developments during the last 15 years have been the discovery of highly active mid-and latetransition metal polymerization catalysts based on iron, cobalt and nickel as well as the discovery of ultra-fast chain transfer agents to give catalyzed chain growth on zinc [5][6][7] and the subsequent development of chain shuttling to give block co-polymers. 8,9 Selective oligomerization reactions of ethylene e.g. trimerization and tetramerization to give 1-hexene and 1-octene constitute another milestone in this area.…”

Section: Introductionmentioning

confidence: 99%

Distinguishing Chain Growth Mechanisms in Metal-catalyzed Olefin Oligomerization and Polymerization Systems: C₂H₄/C₂D₄ Co-oligomerization/Polymerization Experiments Using Chromium, Iron, and Cobalt Catalysts

et al. 2009

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A series of co-oligomerization and co-polymerization reactions of C 2 H 4 /C 2 D 4 (1:1) mixtures have been carried out using various transition metal catalysts based on Cr, Co and Fe in combination with MAO. The oligomeric α-olefin products have been analysed by GC and GC/MS and the experimental results have been compared with the theoretical mass spectra derived from mathematical models. Solid polymer samples have been analysed by 13 C{ 1 H} and 13 C DEPT-135 NMR spectroscopy. C 2 H 4 /C 2 D 4 co-oligomerization can be used as a method to differentiate between a metallacyclic or a Cossee-type chain growth mechanism in oligomerization systems. In the case of a metallacyclic mechanism, no H/D scrambling is observed whereas for a Cossee-type mechanism, similar rates of chain propagation and chain termination (β-H elimination) result in rapid H/D scrambling of the C 2 H 4 /C 2 D 4 feed. This method is therefore limited to oligomerization systems and cannot be applied in polymerization systems where the rate of chain propagation is much faster than the rate of chain termination.

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“…Especially in the case of group 4, these new catalysts and cocatalyst/activators have achieved great success in the production of advanced polyolefin materials [4]. The new systems are able to control product molecular weight, polydispersity, comonomer enchainment level and pattern, the tacticity of poly(a-olefins) [17,56,57], copolymerization of olefins with polar comonomers (group 10) [54,55,[58][59][60][61][62], and the catalytic synthesis of block copolymers by processes such as chain shuttling polymerization [63][64][65][66][67].…”

Section: Introductionmentioning

confidence: 99%

Supported Single-Site Organometallic Catalysts for the Synthesis of High-Performance Polyolefins

2014

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Single-site organometallic catalysts supported on solid inorganic or organic substrates are making an important contribution to heterogeneous catalysis. Early and late transition metal single-site catalysts have changed the polyolefin manufacturing industry and research with their ability to produce polymers with unique properties. Moreover, several of these catalysts have been commercialized on a large scale. Their heterogenization for slurry or gas phase olefin polymerization is important to produce polyolefin as beads and to avoid reactor fouling. The large majority of supports currently used in industry are inorganic materials (SiO 2 , Al 2 O 3 , MgCl 2 ), with silica being the most important. Single-site supported catalysts are most commonly prepared by molecular-level anchoring/chemisorption, in which a molecular precursor undergoes reaction with the surface while maintaining most of the ligand sphere of the parent molecule. Chemisorption of discrete organometallic complexes on solid supports yields catalysts with well-defined active sites, greater thermal stability than the homogeneous analogues, and decreased reactor fouling versus the homogeneous analogues. This review presents a detailed account of the synthesis, characterization and polymerization properties of single-site catalysts supported on metal oxides and metal sulfated oxides, primarily carried out at Northwestern University.

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Catalytic Production of Olefin Block Copolymers via Chain Shuttling Polymerization

Cited by 876 publications

References 23 publications

Living polymerization of olefins with ansa-dimethylsilylene(fluorenyl)(amido)dimethyltitanium-based catalysts

Living polymerization of olefins with ansa-dimethylsilylene(fluorenyl)(amido)dimethyltitanium-based catalysts

Distinguishing Chain Growth Mechanisms in Metal-catalyzed Olefin Oligomerization and Polymerization Systems: C₂H₄/C₂D₄ Co-oligomerization/Polymerization Experiments Using Chromium, Iron, and Cobalt Catalysts

Supported Single-Site Organometallic Catalysts for the Synthesis of High-Performance Polyolefins

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Catalytic Production of Olefin Block Copolymers via Chain Shuttling Polymerization

Cited by 876 publications

References 23 publications

Living polymerization of olefins with ansa-dimethylsilylene(fluorenyl)(amido)dimethyltitanium-based catalysts

Living polymerization of olefins with ansa-dimethylsilylene(fluorenyl)(amido)dimethyltitanium-based catalysts

Distinguishing Chain Growth Mechanisms in Metal-catalyzed Olefin Oligomerization and Polymerization Systems: C2H4/C2D4 Co-oligomerization/Polymerization Experiments Using Chromium, Iron, and Cobalt Catalysts

Supported Single-Site Organometallic Catalysts for the Synthesis of High-Performance Polyolefins

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Distinguishing Chain Growth Mechanisms in Metal-catalyzed Olefin Oligomerization and Polymerization Systems: C₂H₄/C₂D₄ Co-oligomerization/Polymerization Experiments Using Chromium, Iron, and Cobalt Catalysts