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Metallocene polymerization | ||||||||
Metallocene polymerization vs. Ziegler-Natta | ||||||||
Metallocene polymerization is doing great business in the plastics business. It is causing a stir because it is the most popular for vinyl polymers since the invention of Ziegler-Natta polymerization. The reason for all the fuss is that the polymerization of metallocene catalysis allows polyethylene to be made that can stop the bullets! This new polyethylene is better than Kevlar to manufacture bulletproof vests. It has a much higher molecular weight (six or seven million) than the polyethylene made by the Ziegler-Natta recipe. Metallocene polymerization is also good for making polymers of very specific tacticities. It can be adjusted to make isotactic and syndiotactic polymers, depending on what you need. | ||||||||
Metallocene | ||||||||
Metallocene polymerization is also good for making polymers of very specific tacticities. It can be adjusted to make isotactic and syndiotactic polymers, depending on what you need. I could simply say that the metallocene polymerization is a polymerization catalyzed by metallocenes. What is a metallocene? The metallocene is a metal ion with positive charge interspersed between two anions of cyclopentadienyl with negative charge. A cyclopentadienyl anion is a small and clever ion that is made of a small molecule called cyclopentadiene. For example, these cyclopentadienide ions have a charge of -1, so that when a cation arrives, such as Fe with a charge of +2, two of the anions form an iron sandwich. That iron sandwich is called ferrocene. | ||||||||