Abstract
N-Methylene(morpholinium) ions (carbenium-iminium ions) are responsible for uncontrollable reactions of Lyocell dopes – solutions of cellulose in N-methylmorpholine-N-oxide monohydrate at process temperatures of approximately 100°C – as they are able to induce autocatalytic decomposition of the solvent. The carbenium-iminium ions derived from N-benzylmorpholine-N-oxide (NBnMO) are less reactive, affording innocent products instead of entering an uncontrollable decomposition pathway. The “dangerous” carbenium-iminium ions derived from NMMO are efficiently scavenged by NBnMO, which is in turn converted into these “innocent” NBnMO-derived carbenium-iminium ions. Color generation in NBnMO-stabilized NMMO is far less pronounced, than in the case of the traditionally used phenolic anti-oxidant stabilizers. This suggests that NBnMO could be used in a novel approach to stabilize Lyocell solutions.
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©2005 by Walter de Gruyter Berlin New York
