Abstract
50 years ago, Karl Ziegler and Giulio Natta were awarded the Nobel Prize for their discovery of the catalytic polymerization of ethylene and propylene using titanium compounds and aluminum-alkyls as co-catalysts. Polyolefins have grown to become one of the biggest of all produced polymers. New metallocene/methylaluminoxane (MAO) catalysts open the possibility to synthesize polymers with highly defined microstructure, tacticity, and steroregularity, as well as long-chain branched, or blocky copolymers with excellent properties. This improvement in polymerization is possible due to the single active sites available on the metallocene catalysts in contrast to their traditional counterparts. Moreover, these catalysts, half titanocenes/MAO, zirconocenes, and other single site catalysts can control various important parameters, such as co-monomer distribution, molecular weight, molecular weight distribution, molecular architecture, stereo-specificity, degree of linearity, and branching of the polymer. However, in most cases research in this area has reduced academia as olefin polymerization has seen significant advancements in the industries. Therefore, this paper aims to further motivate interest in polyolefin research in academia by highlighting promising and open areas for the future.
Highlights
One of the most important discoveries in chemistry and in the chemical industries in the last century is that of the Ziegler-Natta catalysts for the polymerization of olefins [1,2,3]
Greater research is being conducted by industries and this paper aims to restore the interest in polyolefins within academic institutions
In this paper we have given a review of the changes and current state of PE and PP manufacturing processes, including role and types of catalysts and co-catalysts employed over the years
Summary
One of the most important discoveries in chemistry and in the chemical industries in the last century is that of the Ziegler-Natta catalysts for the polymerization of olefins [1,2,3]. In 1953, Karl Ziegler discovered the catalyst based on titanium tetrachloride (TiCl4) and diethylaluminium chloride [(C2H5)2AlCl] as a co-catalyst for the polymerization of ethylene [4,5] into high molecular weight HDPE (high density polyethylene) at room temperature (Figure 1 shows a photo of the original equipment employed by Ziegler) [3,4,5,6,7] This catalyst was utilized by Giulio Natta to polymerize propylene into crystalline PP (polypropylene) [8]. These magnesium/titanium-based catalysts were designated as second-generation Ziegler-Natta catalysts Due to their very high activities, the residual catalysts did not need to be removed from the polymers and, catalyst removal steps were no longer necessary as part of the manufacturing process. Greater research is being conducted by industries and this paper aims to restore the interest in polyolefins within academic institutions
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
