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Process for the dissolution of cellulose in organic solvents, solutions obtained by said process, and process for the production of formed bodies of regenerated cellulose from said solutions
Process for the dissolution of cellulose in organic solvents, solutions obtained by said process, and process for the production of formed bodies of regenerated cellulose from said solutions
A process for the dissolution of cellulose in organic solvents such as dimethylformamide, dimethylacetamide, and N-methylpyrrolidone is described which comprises contacting the cellulose with an excess of paraformaldehyde and with the solvent at elevated temperatures, preferably higher than 115° C. The amount of paraformaldehyde used preferably corresponds to at least 13 CH.sub.2 O units per anhydroglucosidic unit of the cellulose. The solution obtained can be rendered stable at room temperature by heating it under stirring to lower the paraformaldehyde content, preferably to not less than 8 CH.sub.2 O units per anhydroglucosidic unit. Formed bodies of regenerated cellulose can be obtained from said solutions by coagulating them in an aqueous bath, which may be alkaline or may be a mixture of water and the solvent of the solution, or even by evaporating the solvent.
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