Über den einfluß von sauerstoff auf titanhaltige metallorganische mischkatalysatoren

Abstract

zum 65. Geburtstag gewidmet (Eingegangen am 1. August 1963) ZUSAMMENFASSUNG:Die Oxydation von TiCI, mit 0, in Gegenwart von Aromaten liefert neben Titan-aroxyVerbindungen in der Hauptsache TiOCl, und TiC14, in Gegenwart von geradkettigen Paraffinkohlenwasserstoffen praktisch nur TiOCl, und TiCl,. Diese Reaktion ist bei der Niederdruckpolymerisation von Athylenen mit titanhaltigen ZIEGLER-Katalysatoren bei Zugabe kleiner Mengen 0, auch moglich. Das gebildete TiCI, bewirkt meist die Erhohung der Polymerisationsaktivitat. SUMMARY:The oxidation of TiCl, with 0, in presence of aromatic hydrocarbons yields mainly TiOCI, and TiCl,, besides Ti-aroxyl compounds ; in presence of linear paraffin hydrocarbons there is only TiOCl, and TiC14. The reaction also occurs in low pressure polymerization of ethylenes with ZIEGLER-catalysts containing Ti on addition of small amounts of 0,. The

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

“…The reactions of oxygen with alkyl aluminums have been investigated in many references where most of these studies were conducted on the first generation catalysts. [ 12–14 ] Oxygen is believed to react with the alkyl aluminum as follows: $$$$\begin{equation} {\mathrm{O}}_{2}+\mathrm{Al}{\mathrm{R}}_{3}\stackrel{\mathrm{yields}}{\to}{\mathrm{R}}_{2}\mathrm{AlOOR} \end{equation}$$$$…”

“…[ 15 ] More reactions with the different crystalline forms of TiCl 3 (first and second generation catalysts) have been proposed with varying positive and negative effects on catalyst activity depending on the form of TiCl 3 and the co‐catalyst used. [ 12–15 ]…”

“…[15] More reactions with the different crystalline forms of TiCl 3 (first and second generation catalysts) have been proposed with varying positive and negative effects on catalyst activity depending on the form of TiCl 3 and the co-catalyst used. [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.…”

“…The reactions of oxygen with alkyl aluminums have been investigated in many references where most of these studies were conducted on the first generation catalysts. [12][13][14] Oxygen is believed to react with the alkyl aluminum as follows:…”

“…They have shown as well that the deactivation effect of methanol is due to the decrease in the active sites concentration while both the reaction with and without methanol had similar propagation constants. They checked the stereoregularity of the polymers using 13 C NMR and did not observe any effects.…”