ISSN:
1022-1352
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
The effect of varying 14CO contact time upon the concentration of active centres C* in ethylene homopolymerization using the TiCl4/MgH2 · Al(C2H5)3 catalytic system shows that the polymer radioactivity, and hence C*, increase sharply in the first sixty minutes of 14CO contact with the polymerization centres. For contact times longer than one hour, the polymer radioactivity continues to increase, but very slowly. Studies on the effect of the mole ratio Al(C2H5)3/Ti on ethylene homopolymerization show that both the catalytic activity and C* increase sharply when increasing the mole ratio Al(C2H5)3/Ti in the range from 5 to 20. When increasing the mole ratio Al(C2H5)3/Ti above 50, C* tends to decrease very slightly. In ethylene/1-hexene copolymerization a similar effect of the mole ratio Al(C2H5)3/Ti on the polymerization is observed. However, even though the catalytic activity in copolymerization is observed to be higher than in homopolymerization, at the same mole ratio Al(C2H5)3/Ti, yet C* in both cases is found to be more or less the same.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1994.021950718
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