Influence of carbon dioxide and carbon monoxide on the kinetics of propylene polymerization

Lesná, Marie; Mejzlík, Jiří

doi:10.1007/bf02070376

Cited by 14 publications

(4 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Reactions of alcohols and carbon oxides have been investigated extensively on the early generations of Ziegler–Natta catalysts within the contexts of counting active centers. [ 16–19 ] Carbon dioxide interaction with the catalyst is believed to be a selective adsorption on the formed active centers which is reversible in nature. [ 16 ]…”

Section: Resultsmentioning

confidence: 99%

“…[ 16–19 ] Carbon dioxide interaction with the catalyst is believed to be a selective adsorption on the formed active centers which is reversible in nature. [ 16 ]…”

Section: Resultsmentioning

confidence: 99%

“…[12][13][14][15] Reactions of alcohols and carbon oxides have been investigated extensively on the early generations of Ziegler-Natta catalysts within the contexts of counting active centers. [16][17][18][19] Carbon dioxide interaction with the catalyst is believed to be a selective adsorption on the formed active centers which is reversible in nature. [16] Although it is certain that the poisons we have used in our experiments readily react with the TiBA, however, since all the poisons have been introduced after the reaction has started, the drop in catalyst activity is most likely not completely due to reactions with the co-catalyst, their by-products or the reduction of activating power due to the resulting organoaluminum species.…”

Section: Possible Mechanisms Of Poisoningmentioning

confidence: 99%

“…[16][17][18][19] Carbon dioxide interaction with the catalyst is believed to be a selective adsorption on the formed active centers which is reversible in nature. [16] Although it is certain that the poisons we have used in our experiments readily react with the TiBA, however, since all the poisons have been introduced after the reaction has started, the drop in catalyst activity is most likely not completely due to reactions with the co-catalyst, their by-products or the reduction of activating power due to the resulting organoaluminum species. It is safe to assume that most of the active sites are formed in the beginning of the reaction by the co-catalyst.…”

Section: Possible Mechanisms Of Poisoningmentioning

confidence: 99%

See 3 more Smart Citations

Impact of Process Poisons on the Performance of Post‐Phthalate Supported Ziegler–Natta Catalysts in Gas Phase Propylene Polymerization

Albeladi

Moman

McKenna

2022

Macro Reaction Engineering

View full text Add to dashboard Cite

The impact of common process catalyst poisons on the performance of a 6th generation Ziegler–Natta catalysts during the gas phase polymerization of propylene are examined using two approaches: introducing propylene without purification, or with one or two sets of purification columns, and by introducing carbon dioxide (CO2), oxygen (O2), water (H2O), methanol (CH3OH), ethyl acetate (C4H8O2) and dimethyl sulfoxide (C2H6SO) during the polymerization. As expected, purification columns increases the catalyst activity significantly, slightly reduce catalyst decay. Injecting TiBA during the reaction leads to an activity increase. The addition of two full sets of columns substantially increased the repeatability of polymerization reactions. The power of deactivation of poisons injected during the polymerization reaction is: O2 > CO2 > CH3OH > C2H6SO > C4H8O2 > H2O. Adding CO2, O2, and CH3OH resulted in a progressive decrease in molecular weight while almost no effect is observed with H2O. However, C4H8O2, and C2H6SO resulted in a mild increase in molecular weight. Additionally, the effects on crystallinity and stereoregularity are similar where CO2, O2, H2O and CH3OH caused a progressive decrease while C4H8O2 and C2H6SO resulted in a mild increase, indicating some isotacticity control by these two poisons.

show abstract

Section: Resultsmentioning

confidence: 99%

“…[ 16–19 ] Carbon dioxide interaction with the catalyst is believed to be a selective adsorption on the formed active centers which is reversible in nature. [ 16 ]…”

Section: Resultsmentioning

confidence: 99%

Section: Possible Mechanisms Of Poisoningmentioning

confidence: 99%

Section: Possible Mechanisms Of Poisoningmentioning

confidence: 99%

See 2 more Smart Citations

Impact of Process Poisons on the Performance of Post‐Phthalate Supported Ziegler–Natta Catalysts in Gas Phase Propylene Polymerization

Albeladi

Moman

McKenna

2022

Macro Reaction Engineering

View full text Add to dashboard Cite

show abstract

Bestimmung der Konzentration der aktiven Zentren bei der durch Tetrabenzyltitanium/Aluminiumbromid katalysierten Ethylenpolymerisation

1983

View full text Add to dashboard Cite

Die Zahl der aktiven Zentren bei der rnit Tetrabenzyltitanium/Aluminiumbromid katalysierten Ethylenpolymerisation in Toluen bei 0 "C wird durch Bestimmung der Konzentration der Metall-Polymer-Bindungen in Abhangigkeit vom Umsatz durch Ahbruch der Polymerisation rnit in der Hydroxylgruppe tritiiertem Butan-1-01 ermittelt. Der dazu notwendige Isotopeneffekt wird nach der Methode der tropfenweise variablen Zugabe des tritiierten Butanols bestimmt. Eswird die Geschwindigkeitskonstante des Kettenwachstums berechnet. Die Ergebnisse werden diskutiert. Onpeaemme mnyenmpayuu axmuenm yenmpoe npu nonuntepuaayuu emunena na tcaamcucuaanwpe mempa6e~wmuman + 6po.wua wm.uunuR % W I O aKTElBH€dX UeHTPOB IIpH IIOJIElMepH3CU(HH aTIlJIeHa H a KaTaJlHXlTOpe TeTpa6eH3ElJ"UTatI$-GPOMEIA aJIIOMHHHtI B TOJIyOJIe IIpH 0 "c OIIpeJ(eJIeH0 ElCCJIeJ(0BaHEleM 8aBHCHMOCTli KOHqeHTpCU(ElH MeTaJIJIOIIOJIHMePHbIX CBIIWB OT BbIXOJ(a ItOnHaTYIJIeHa C IlOMOqbIO MeToRa o6pb1~a nOJIElMepR3CU(HH 6yTaH-l-OJIOM, MeqeHbIM TpHTEleM B OH-rpynne. HeoBxomi-M M a AJIR aTOrO El80TOIIHbIa a@@KT OqeHeH MeTOJ(0M ~p 0 6~0 f i HeIIOCTOJ3HHOt IIOAaVEl MeqeHOrO 6y~m-l-oza. B m E l c n e H a KOHCTaETa CKOpOCTEl POCTa IIOJlHMepHOfi 4eIM El o 6 c y w e~n peayJIbTaTbI. Estimation of the concentration of active centres on the polymerization of ethylene catalyzed by tetrabenzyltitaniurn/alurniniumbromideThe number of active centres in the polymerization of ethylene catalyzed by tetrabenzyltitanium/aluminiumbromide in toluene at 0°C was determined by measuring the concentration of metal-polymer bonds as a function of the polymer yield by quenching of the polymerization with hydroxytritiated butan-1-01. The necessary isotope effect for it is determined by varying dropwise addition of tritiated butan-1-01. The propagation rate constant is evaluated. The results are discussed.

show abstract

Comparison of methods for determination of the number of active centers in Ziegler‐Natta polymerizations

1983

View full text Add to dashboard Cite

Four intrinsically different methods for the determination of the number of active centers were employed in propylene polymerization catalyzed by the typical heterogeneous system TICI, /AlEt,Cl: (i) determination of M, (GPC method) and calculation of number of macromolecules therefrom; (ii) quenching with BuOT and determination of tritium in the polymer; (iii) quenching with CO or CO, and determination of carbonyl groups in the polymer (IR spectroscopy); (iv) quenching with SO, and determination of sulfur in the polymer. The first two methods exhibited a reasonable agreement for the number of active centers. Method (iii) gave much lower values, whereas method (iv) was found to be virtually unsuitable due to a high extent of side reactions of SO, with the polymer. A similar comparison of the methods was made in ethylene polymerization catalyzed by the typical homogeneous systems Cp,TiEtCl/AIEtCl, and Cp,TiEtCl/alumoxane. Method (ii) gave a much lower number of active centers than method (i), due perhaps to a low extent of alcoholysis of the Ti-C bond or to a high kinetic isotope effect. CO, appeared to be entirely inert as a quenching agent and CO had been reported to show side reactions. It follows that none of the above quenching methods have universal application and thus literature data should be considered with caution.

show abstract

Influence of carbon dioxide and carbon monoxide on the kinetics of propylene polymerization

Cited by 14 publications

References 5 publications

Impact of Process Poisons on the Performance of Post‐Phthalate Supported Ziegler–Natta Catalysts in Gas Phase Propylene Polymerization

Impact of Process Poisons on the Performance of Post‐Phthalate Supported Ziegler–Natta Catalysts in Gas Phase Propylene Polymerization

Bestimmung der Konzentration der aktiven Zentren bei der durch Tetrabenzyltitanium/Aluminiumbromid katalysierten Ethylenpolymerisation

Comparison of methods for determination of the number of active centers in Ziegler‐Natta polymerizations

Contact Info

Product

Resources

About