ISSN:
0360-6376
Keywords:
Physics
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Kinetics for the polymerization of ethylene and the copolymerization of ethylene and propylene were studied by using highly effective heterogeneous metal organic catalysts produced by coating different organic and inorganic supports with the components of Ziegler systems. The activity of a supported Ziegler catalyst is characterized by the physical parameters of the support structure and its chemical nature. The active role of magnesium-containing supports was established for the formation and functioning of the propagating species on their surfaces. This role is expressed not only by an increase in the portion of transition metal included in the propagating species, compared with typical Ziegler catalysts, but also by an increase in the reactivity of the propagating species, change in the nature of the elementary processes for polymerization and copolymerization, including control of copolymerization constants, and modification of the molecular structure of the polymers and copolymers. It was shown that by choice of support it is possible to control the activity of the same catalytic system and characteristics of the structure and properties of the polymers it produces under identical polymerization conditions.
Additional Material:
4 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pol.1980.170180702
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