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On the polymerization of N,N,N′,N′-tetramethyl-α,ω-alkanediamines with dibromoalkanes—an in-situ NMR study

✍ Scribed by Jianguo Wang; Wolfgang H. Meyer; Gerhard Wegner

Publisher: John Wiley and Sons
Year: 1994
Tongue: English
Weight: 767 KB
Volume: 195
Category: Article
ISSN: 1022-1352
DOI: 10.1002/macp.1994.021950527

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✦ Synopsis

Abstract

Based on the Menschutkin reaction, α,ω‐alkanediamines with α,ω‐dibromoalkanes were employed to synthesize cationic polyelectrolytes named ionenes. By means of in‐situ ^13^C NMR we have characterized the influence of ionic charges on the reactivity of the polymerizing species. The progress of aliphatic ionene polymerization has been found to be a complex reaction. At least four elementary building reactions and two side reactions (Hoffmann degradation and intramolecular cyclization) have been detected in the course of ionene polymerization. As a result, the broad molecular weight distribution which is usually found in ionenes can be explained in terms of the kinetics and by side reactions. Also, the difficulty of achieving high molecular weight ionenes can be understood on the basis of our NMR results.

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