PROCEDURE FOR THE PRODUCTION OF FORMAL CELLULOSE AND FORMAL CELLULOSE PRODUCTS

摘要

An improved process is provided for making a precipitated cellulose product wherein cellulose is dissolved in a solvent containing both a tertiary amine N-oxide solvent and water and precipitated therefrom with water or other non-solvent for cellulose. The water content of the solution may be adjusted to any level of up to about 29% by weight with the amount of water decreasing substantially linearly as the cellulose is increased. A solution substantially free from undissolved cellulose and solid tertiary amine N-oxide which is adapted to be spun, extruded or molded at a temperature below the melting point of the tertiary amine N-oxide can be prepared with a solvent which contains water within a specified critical range mixed with the tertiary amine N-oxide. Preferably, N,N,N-triethylamine N-oxide or a tertiary amine N-oxide having a cyclic or pseudo-cyclic molecular structure is mixed with water to form the solvent.