ISSN:
0449-2951
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
Some ternary catalytic systems used in the polymerization of butadiene to a prevailingly 1,4-cis product are described. They make use of some aluminum hydride derivatives, aluminum iodide, and titanium tetrachloride. For each catalytic system we have adopted conditions to obtain the maximum yield of polymer and the highest content of 1,4-cis units. Such optimum conditions are achieved at certain molar ratios of aluminum hydrides/TiCl4 and AlI3/TiCl4. In particular, for a constant amount of AlI3 and TiCl4, the choice of the optimum ratio of hydride/TiCl4 depends on the quantity of active hydrogens present in the aluminum compounds while it does not depend on the type substituents, e.g., chloro, amino groups, etc. The presence of Lewis bases, which tend to stabilize some aluminum hydrides and make them soluble in the reaction medium, does not influence the course of polymerization provided such bases are present in stoichiometric amount with respect to the aluminum. If, however, these complexing agents are in excess, a decrease of the catalytic activity and 1,4-cis content is noticed. This is more so, the stronger the basicity of the complexing Lewis base added. The results obtained in the polymerization of butadiene by means of numerous laboratory runs were confirmed by pilot-plant runs.
Additional Material:
13 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pol.1965.100030229
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