The Ethylene Polymerization with Ziegler Catalysts: Fifty Years after the Discovery

Abstract

Fifty years ago, Karl Ziegler and his co-workers discovered the synthesis of polyethylenes at low pressures and moderate high temperatures with transition-metal catalysts of the 4th group and aluminum organic compounds as cocatalysts. The last 50 years represent a story of innovations in science and industry in the development of high-activity catalysts and processes based on a detailed understanding of all relevant chemical and physical processes on all scales. Catalysts, technologies, and products are still under further development, which shows that the potential of this polymerization process is not fully exploited. Today's targets include achieving better product properties at lower production costs and the substitution of other materials, such as glass, paper, steel, and concrete in certain fields because polyethylenes deliver better resource-saving solutions.

XAS and XES Techniques Shed Light on the Dark Side of Ziegler–Natta Catalysts: Active‐Site Generation

“…Covering still increasing volumes of the polyolefin production sector (that is approaching 150 MTons/year), [1][2][3][4][5][6] heterogeneous…”

Comparison of catalytic ethylene polymerization in slurry and gas phase

“…Some authors have reported (using IR thermography) that the surface temperature of such particles could be up to 30°C higher than the bulk temperature [26]. Keeping the bulk temperature of the reactor constant and the particle temperature below the softening temperature of the polymer is the best arrangement for a catalytic polyolefin polymerization reactor [69].…”

Optimal Catalyst and Cocatalyst Precontacting in Industrial Ethylene Copolymerization Processes

“…Since the first Z-N polymerization in 1953 by Karl Ziegler and his research team, there is a constant progress in catalyst design to increase the catalyst activity, micro structure control and powder morphology [2]. Especially with the use of different heterogeneous support materials such as MgCl 2 and SiO 2 , Z-N catalysts have made a huge leap forward.…”

“…Especially with the use of different heterogeneous support materials such as MgCl 2 and SiO 2 , Z-N catalysts have made a huge leap forward. The actual 4th-generation catalyst systems show a polymer yield up to 100 Kg pol /g cat for olefin polymerization [2,3]. With increasing activity, less catalyst is required for achieving the same amount of polymer produced in a polymerization reactor.…”

“…Out of these two components an active site is formed (i.e., catalyst active site), which is the polymerization loci [2]. The formation of the active sites has a major influence on the catalyst productivity.…”