ISSN:
0021-8995
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
In this paper, the synthesis of different catalytic systems based on the reduction of TiCl4 by Grignard compounds has been systematically studied. The catalysts exhibited the highest activities when used in the copolymerization of ethylene with n-hexene. The profile of the kinetic curves also changed when the comonomer was present during polymerization. By thermal analysis and scanning electron microscopy techniques, it could be found that the incorporation of the comonomer to the polymer chain brings about a decrease in the polymer crystallinities and an increase in the porosities of the growing particles. Due to that, the diffusion of the monomer to the catalytic active centers takes place more easily, consequently increasing the polymerization rate. In addition, catalysts control better the morphology (size and shape) of the nascent polymer particles when used for copolymerization.
Additional Material:
7 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/app.1987.070340309
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