Control of Polymer Molecular Weight

This electronic ring substitution effect was further examined by other scientists that found that bis(n-butylcyclopentadienyl) zirconium dichloride/ MAO catalyst provided a commercially important catalyst system for the gas-phase process used in the commercial manufacture of polyethylene [45,46]. 

4 Single-Site Catalyst Based on (BuCp)2ZrCl2/ 

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Telechelic and semitelechelic polymers have been synthesized by a variety of free radical, anionic and, most recently, cationic techniques (1.2.9-12). The advantages of anionic procedures include functional purity, versatility of substitution, and monodisper-sity and control of polymer molecular weights. This... 

Explain how molecular hydrogen performs a control of polymer molecular weight in olefin polymerisation with Ziegler-Natta catalysts. 

Chaudhary, A. K., Beckman, E. J., and Russell, A. J., Rational control of polymer molecular weight and dispersity during enzyme-catalyzed polyester synthesis in supercritical fluids, J. Am. Chem. Soc., 117, 3728-3733, 1995. 

Figure 2.1 5 Melt Flow Indexer used for the quality control of polymer molecular weight.

Through the careful control of polymer molecular weight and composition, oils of constant performance over broad temperature ranges are made possible... 

Othman NS, Fevotte G, Peycelon D, Egraz J-B, Suau J-M. Control of polymer molecular weight using near infrared spectroscopy. AIChE J 2004 50 654-664. 

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