Copolymerization of Ethylene and Propylene with Functionalized Vinyl Monomers by Palladium(II) Catalysts

Johnson, Lane R.; Mecking, Stefan; Brookhart, Maurice

doi:10.1021/ja953247i

Cited by 1,313 publications

(898 citation statements)

References 8 publications

Supporting

Mentioning

863

Contrasting

Unclassified

Order By: Relevance

“…Our work is based on the discovery of Pd II -␣-bisimine chain-walking catalysts by Brookhart et al 47 Brookhart and coworkers 46,47 and Mohring and Fink 59 discovered that when certain Ni II and Pd II catalysts were used for ethylene polymerization, branched PEs, instead of linear PEs, were obtained. They also observed a chainstraightening phenomenon in ␣-olefin polymerizations with those Ni II and Pd II catalysts.…”

Section: Chain Walking: a New Strategy For Controlling Polymer Topologymentioning

confidence: 99%

“…Proposed chain-walking mechanism. 46,47,59 CONTROL OF POLYMER TOPOLOGY polymer chain after each insertion. This random walk of the catalyst followed by the insertion of ethylene should result in a hyperbranched or dendritic polymer.…”

Section: Chain Walking: a New Strategy For Controlling Polymer Topologymentioning

confidence: 99%

“…47,48,75,76 By copolymerizing ethylene with functional monomers at different P E 's, we have obtained copolymers carrying a variety of functional groups with tunable topologies (Scheme 5). 56 This offers a simple one-pot approach to the design of functional polymers with a broad range of topologies.…”

Section: Chain Walking: a New Strategy For Controlling Polymer Topologymentioning

confidence: 99%

“…Inspired by the recent progress in late-transition-metal polymerization catalysis, [43][44][45][46][47][48][49] we have been exploring the concept of controlling polymer topology with late-transition-metal catalysts with the goal of creating polymers with new topologies from simple existing monomers (Fig. 2).…”

Section: Introductionmentioning

confidence: 99%

“…[51][52][53] In another strategy, 54 -56 polyethylene (PE) topology has been successfully controlled by the regulation of the competition between propagation and chain walking for ethylene polymerization with a Pd II -␣-bisimine catalyst. 47 This article reviews a few recent developments in our own laboratory and in laboratories of other researchers on the control of polymer topology with late-transition-metal catalysts.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Z. Guan, Control of polymer topology through late‐transition‐metal catalysis, J Polym Sci Part A: Polym Chem (2003), 41(22), 3680–3692

Guan

2003

J. Polym. Sci. A Polym. Chem.

View full text Add to dashboard Cite

ABSTRACT:In this article, recent examples are reviewed of late-transition-metal catalysis applied to polymer topology control. By the judicious selection or design of latetransition-metal catalysts, polymers with a broad range of topologies, including linear, short-chain-branched, hyperbranched, dendritic, and cyclic topologies, have been successfully synthesized. A distinctive advantage of the catalyst approach is that polymers with complex topologies can be prepared in one pot from simple commercial monomers. A fundamental difference of the catalyst approach with respect to other approaches is that the polymer topology is controlled by the catalysts instead of the monomer structure. In our own laboratory, we have successfully used two strategies to control the polymer topology with late-transition-metal catalysts. In the first strategy, hyperbranched polymers are prepared by the direct free-radical polymerization of divinyl monomers through control of the competition between propagation and chain transfer with a cobalt chain-transfer catalyst. In the second strategy, polyethylene topology is successfully controlled by the regulation of the competition between propagation and chain walking with the Brookhart Pd II -␣-bisimine catalyst.

show abstract

Section: Chain Walking: a New Strategy For Controlling Polymer Topologymentioning

confidence: 99%

Section: Chain Walking: a New Strategy For Controlling Polymer Topologymentioning

confidence: 99%

Section: Chain Walking: a New Strategy For Controlling Polymer Topologymentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Z. Guan, Control of polymer topology through late‐transition‐metal catalysis, J Polym Sci Part A: Polym Chem (2003), 41(22), 3680–3692

Guan

2003

J. Polym. Sci. A Polym. Chem.

View full text Add to dashboard Cite

show abstract

Ethylene coordination, insertion, and chain transfer at a cationic aluminum center: A comparative study withAb Initio correlated level and density functional methods

2000

View full text Add to dashboard Cite

The performance of correlated ab initio methods and DFT methods was compared for the propagation and chain transfer steps of ethylene polymerization by a model aluminum–amidinate system, [{HC(NH)2}AlCH2CH3]+. All methods agree that the main chain transfer mechanism is β‐hydrogen transfer to the monomer (BHT), and that this is substantially easier than propagation; implications for the real Jordan system are discussed briefly. Counterpoise corrections are necessary to obtain reasonable olefin complexation energies. Activation energies are consistently lower at DFT (BP86, B3LYP) than at ab initio levels [MP2, MP3, MP4, CI, CCSD(T)]; the differences are particularly large (16 kcal/mol) for the BHT reaction. This is suggested to be related to the known problem of DFT in describing hydrogen bridged systems. © 2000 John Wiley & Sons, Inc. J Comput Chem 21: 398–410, 2000

show abstract

Ethylene polymerization initiated by anchored CpIndZrCl2 on silica with hexamethyltrisiloxane and pentamethylene spacers

Lee

Noh

et al. 1999

J. Appl. Polym. Sci.

View full text Add to dashboard Cite

For ethylene polymerization, the supported metallocene catalyst was prepared by anchoring CpIndZrCl 2 on silica with an appropriate spacer. The three procedures were applied for CpIndZrCl 2 anchoring on silica with a hexamethyltrisiloxane or pentamethylene spacer. The anchoring procedures exerted a strong influence on the catalyst activity since the different anchoring methods gave the formation of different structures of active sites. With the new anchoring route, it was possible to prepare the "heterogeneous single-site" catalyst which was found to have only one catalyst structure on silica and exhibited a higher catalyst activity than that of the other supported catalysts. At a polymerization temperature of 70°C, the activity of the heterogeneous single-site catalyst was comparable to that of the unsupported homogeneous zirconocene.

show abstract

Copolymerization of Ethylene and Propylene with Functionalized Vinyl Monomers by Palladium(II) Catalysts

Cited by 1,313 publications

References 8 publications

Z. Guan, Control of polymer topology through late‐transition‐metal catalysis, J Polym Sci Part A: Polym Chem (2003), 41(22), 3680–3692

Z. Guan, Control of polymer topology through late‐transition‐metal catalysis, J Polym Sci Part A: Polym Chem (2003), 41(22), 3680–3692

Ethylene coordination, insertion, and chain transfer at a cationic aluminum center: A comparative study withAb Initio correlated level and density functional methods

Ethylene polymerization initiated by anchored CpIndZrCl2 on silica with hexamethyltrisiloxane and pentamethylene spacers

Contact Info

Product

Resources

About