Butyl chloride as promoter in ethylene polymerization by magnesium ethoxide‐supported catalyst

Abstract

The effects of butyl chloride as a promoter in the ethylene polymerization were studied using a Mg(OEt) 2 /TiCl 4 /triethyl aluminum (TEA) Ziegler-Natta catalyst system, where Mg(OEt) 2 , TiCl 4 , TEA were used as support, catalyst, and activator, respectively. The influence of BC on the catalyst performance, polymerization rate, and polymer properties were investigated. This study strongly indicates that BC could act as a promoter with high performance in the ethylene polymerization. There was a remarkable increase in the catalyst yield and polymerization rate, in particularly, in the presence of hydrogen which was used for controlling the molecular weight. A reduction in the polymer molecular weight was observed in the presence of BC and hydrogen. The morphology of the polymers was evaluated through scanning electron microscopy and particle size distribution. V C 2013 Wiley Periodicals, Inc. J. Appl.Polym. Sci. 2014, 131, 40189.

Promoting ethylene polymerization through cocatalyst modification

“…It can be resulted in the improvement in the chain transfer agent role of TEA. For this reason, a reduction in the polymer molecular weights is observed [15]. Similarly, the same behavior was observed when hydrogen was used in the polymerization.…”

“…When cyclohexyl chloride was applied, the molecular weight decreased further. In other words, an enhancement in the catalyst-hydrogen response can be obtained using less amount of hydrogen for producing polymers with a certain molecular weight in the presence of a suitable promoter in the ethylene polymerization system [15].…”

“…An improved catalyst-hydrogen response results in an increased MFI. Therefore, in the polymerization systems containing promoter, a less amount of H 2 is required to reach a specific MFI [15]. DSC analysis has been employed to measure the values of T m , T c and X c of the produced polymers.…”

“…Among them, cyclohexyl chloride (CHC), butyl chloride, cyclopentyl chloride, and benzyl chloride have been the most effective promoters [13][14][15][16]. Furthermore, although some highly effective promoters were reported, there were only a few reports on the details of their behavior in the polymerization and polymer properties.…”

“…It was shown that the use of the organohalides (halocarbons) as promoters enhances the efficiency of the Ziegler-Natta catalysts in the ethylene polymerization [9,[13][14][15][16]. Accordingly, the catalyst yield may increase over two times in the presence of a certain promoter.…”