Ziegler-Natta catalysts for olefin polymerization: Mechanistic insights from metallocene systems

Huang, Jia; Rempel, Garry L.

doi:10.1016/0079-6700(94)00039-5

Cited by 188 publications

(65 citation statements)

References 33 publications

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“…Metathesis polymerization requires the use of organometallic catalysts in relatively high concentration (typically 100e1000 ppm [51]) compared to the case of polyolefins [52] or elastomers. These ones could accelerate the thermal decomposition of hydroperoxides, as discussed here, using the following kinetic description:…”

Section: On the Stability Of Hydroperoxidesmentioning

confidence: 99%

Kinetic analysis of polydicyclopentadiene oxidation

Defauchy

Gac

Guinault

et al. 2017

Polymer Degradation and Stability

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is an open access repository that collects the work of Arts et Métiers ParisTech researchers and makes it freely available over the web where possible. b s t r a c tThe in situ thermal oxidation of thin unstabilized polydicyclopentadiene was studied by TGA to monitor mass gain, and DSC to characterize hydroperoxides concentration. Results were discussed using kinetic analysis, which allowed the estimation of activation energies for key reactions of the oxidation process. Activation energy for termination was shown to be higher than in hydrocarbon liquids, which was discussed from the theory of diffusion controlled reactions, and a possible link with local motions associated with sub-glassy transition. Activation energy of thermal decomposition of hydroperoxides was found lower than for model hydroperoxides, suggesting an accelerating effect of organometallic catalysts. Despite those two results that indicate a poor thermal stability of thin pDCPD films, measurements of oxygen diffusivity at several temperatures show that oxidation remains confined in a relatively thin surface layer which would allow the pDCPD properties to be preserved.

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Section: On the Stability Of Hydroperoxidesmentioning

confidence: 99%

Kinetic analysis of polydicyclopentadiene oxidation

Defauchy

Gac

Guinault

et al. 2017

Polymer Degradation and Stability

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“…Organometallic catalysts were developed to produce PE with well-defined structures (average molecular mass, crystallization degree, etc …) [1,2]. Oxidation mechanisms [3], kinetics [4] and the subsequent loss of ductility, often so called embrittlement (even if this term is rather linked to the loss of toughness instead of ultimate elongation) [5] are well documented in literature together with the detrimental role of metallic polymerization catalysts on oxidative stability [6].…”

Section: Introductionmentioning

confidence: 99%

Polyethylene loss of ductility during oxidation: Effect of initial molar mass distribution

Reano

Guinault

Richaud

et al. 2018

Polymer Degradation and Stability

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“…20 Figure 7 shows a comparison of the changes in catalytic activities and weight-averaged molecular weight as a function of the cocatalyst/catalyst (Al/Zr) molar ratio for the same polymerization conditions such as the monomer/comonomer feeding ratio, catalyst content, polymerization time, and polymerization temperature.…”

Section: Polymerization Parametersmentioning

confidence: 99%

A Study on the Coordination Polymerization Using C₂-Symmetric Dichloro[rac-ethylenebisindenyl] zirconium(IV)/Methylaluminoxane System

Yang¹,

Kim²,

Park³

et al. 2013

Elastomers and Composites

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ABSTRACT：We synthesized polyethylene, poly(ethylene-co-1-decene), poly(ethylene-co-p-methylstyrene), and poly(ethylene-ter-1-decene-ter-p-methystyrene) using a rac-Et(Ind) 2 ZrCl 2 metallocene catalyst and a methylaluminoxane cocatalyst system. The materials were characterized using nuclear magnetic spectroscopy and fourier transform infrared spectroscopy. To identify suitable reaction conditions for terpolymerization, we studied the effects of catalyst content, cocatalyst/catalyst molar ratio, polymerization time, and polymerization temperature. As the catalyst content increased, the catalytic activity and the molecular weight of the terpolymers increased. The catalytic activity sharply increased but little change was observed after a polymerization time of 30 min. The increase in the cocatalyst/catalyst molar ratio resulted in a decrease in the molecular weight of the terpolymers and an increase in the catalytic activity to some degree. The catalytic activity increased with increasing polymerization temperature, while the molecular weight of the terpolymers decreased. 요 약：rac-Et(Ind)2 ZrCl

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Ziegler-Natta catalysts for olefin polymerization: Mechanistic insights from metallocene systems

Cited by 188 publications

References 33 publications

Kinetic analysis of polydicyclopentadiene oxidation

Kinetic analysis of polydicyclopentadiene oxidation

Polyethylene loss of ductility during oxidation: Effect of initial molar mass distribution

A Study on the Coordination Polymerization Using C₂-Symmetric Dichloro[rac-ethylenebisindenyl] zirconium(IV)/Methylaluminoxane System

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Ziegler-Natta catalysts for olefin polymerization: Mechanistic insights from metallocene systems

Cited by 188 publications

References 33 publications

Kinetic analysis of polydicyclopentadiene oxidation

Kinetic analysis of polydicyclopentadiene oxidation

Polyethylene loss of ductility during oxidation: Effect of initial molar mass distribution

A Study on the Coordination Polymerization Using C2-Symmetric Dichloro[rac-ethylenebisindenyl] zirconium(IV)/Methylaluminoxane System

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A Study on the Coordination Polymerization Using C₂-Symmetric Dichloro[rac-ethylenebisindenyl] zirconium(IV)/Methylaluminoxane System