Use of co-solvents in amine N-oxide solutions

Abstract

This invention relates to the use of certain co-solvents in cellulose amine N-oxide solutions, which co-solvents increase the cellulose dissolution rate; lower the temperatures necessary to reasonably form a solution; lower the viscosity of the solution; provide solutions with improved color, amine oxide stability, and cellulose stability, provide a solution with improved flow characteristics; increase solution processability, e.g. wet spinning; permit the replacement of amine oxides by a less expensive co-solvent; and are recoverable and reusable in cellulose dissolution and processing. The co-solvents of the invention comprise compounds, miscible with cellulose-dissolving amine N-oxides, containing primary, or combinations of primary and secondary, amino groups wherein the amino groups are bonded to alkyl, alicyclic, dialkyl ether or alkyl/alicyclic radical(s) and wherein the number of carbon atoms divided by the number of primary amino groups is approximately equal to or less than 4; or #C/#NH.sub.2 .ltorsim.4 and the number of primary amino groups divided by the number of secondary amine radicals is equal to or greater than 1; that is #NH.sub.2 /#NHR.gtoreq.1.

Dependencies are inferred from the claim text.