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1,4 polymerization of isoprene by titanate catalyst systems

✍ Scribed by Horne, Samuel E. ;Carman, Charles J.

Publisher
Wiley (John Wiley & Sons)
Year
1971
Tongue
English
Weight
729 KB
Volume
9
Category
Article
ISSN
0449-296X

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✦ Synopsis

Abstract

Titanates are versatile in the 1,4 polymerization of isoprene. The (R′O)~4~Ti/RAlCl~2~ catalyst gives either cis‐ or trans‐1,4‐polyisoprene, depending on the nature of both the titanate and the solvent. Primary titanates give cis‐1,4‐polyisoprene in both aliphatic and aromatic solvents. Secondary titanates give cis‐polyisoprene in aliphatic solvents, and trans‐1,4‐polyisoprene in aromatic solvents. Tertiary titanates give trans‐polyisoprene in both aliphatic and aromatic solvents. A mechanism is postulated which takes into consideration the role of the solvent. ESR studies of the various titanate–RAlCl~2~ catalysts were made; the paramagnetic structures are related to polymerization mechanisms.

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