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Use of crown ether in the anionic polymerization of propylene oxide—1. Rate of polymerization

✍ Scribed by Jifeng Ding; Colin Price; Colin Booth

Publisher: Elsevier Science
Year: 1991
Tongue: English
Weight: 332 KB
Volume: 27
Category: Article
ISSN: 0014-3057
DOI: 10.1016/0014-3057(91)90028-m

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✦ Synopsis

Al~tract--The rate of anionic polymerization of bulk propylene oxide catalysed by potassium alkoxide in the presence of 18-crown-6 ether was followed dilatometrically. Rate constants were obtained at 40, 50 and 60 ° over a range of crown ether concentrations, so allowing calculation of activation energies for polymerization with and without added crown ether. The results were consistent with polymerization by ligand-separated and contact ion-pairs in equilibrium.

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