Process for making a shapeable cellulose and shaped cellulose products

In a process for dissolving cellulose in a tertiary amine N-oxide solvent for the cellulose and thereafter shaping the solution and separating the cellulose from the tertiary amine N-oxide, the improvement wherein the solution is prepared with a solvent for the cellulose comprising a tertiary amine N-oxide selected from the group consisting of:

• (a) N,N,N-triethylamine N-oxide and
• (b) tertiary amine N-oxides having one or two of the valence bonds of the nitrogen substituted by a methyl residue and, where one methyl residue is present, the remaining valences are satisfied by a divalent radical forming a 5- to 7-membered ring structure having the N-atom in the ring;
• where two methyl residues are present, the remaining valence is satisfied by
• (1) a monovalent cyclic 5-, 6- or 7-membered residue which may be substituted only by methyl residues at the .beta.- or .epsilon.-positions, or
• (2) by a radical which can form a pseudo-cyclic structure through interaction with the N-oxide functionality, and
• from 0.8% to about 29% by weight of water wherein the maximum water content in the solvent decreases substantially linearly with increase in cellulose content.

In a process which comprises dissolving cellulose in a tertiary amine N-oxide solvent for the cellulose and thereafter shaping the solution and separating the cellulose from the tertiary amine N-oxide, the improvement wherein the solution is prepared with a solvent for the cellulose comprising

• (1) a tertiary amine N-oxide having one of the following structures:
• ##STR9## where X is a radical chain completing a ring comprising 2 to 4 carbon atoms, R.sub.1 and R.sub.2 are H or methyl (Me);
• ##STR10## wherein Z is (i) a saturated or aromatic, unsaturated 5-, 6- or 7-membered ring which may be substituted only by methyl at the .beta.- or .epsilon.-positions;
• or (ii) CH.sub.2 CH.sub.2 W where W can be OH, SH or NH.sub.2, or
• (2) N,N,N-triethylamine N-oxide and from about 0.8% to about 29% by weight of water wherein the maximum water content in the solvent decreases substantially linearly with increase in cellulose content.

A process for making a shaped cellulose article which comprises

• (1) dissolving cellulose in an N,N-dimethylcyclohexylamine N-oxide solvent containing from 0.8% to about 21% weight water with the amount of water in the solution being between amounts determined by solving the equations
• B=37.45-2.10 (% water)
• and
• C=33.57-3.28 (% water)
• with B and C being the percent by weight of cellulose dissolved in the solvent,
• (2) shaping the resulting solution, and
• (3) precipitating the cellulose from the shaped solution, washing the resulting shaped precipitated cellulose substantially free from N,N-dimethylcyclohexylamine N-oxide and drying the shaped precipitated cellulose.

A process for making a shaped cellulose article which comprises

• (1) dissolving cellulose in N,N,-dimethylethanolamine N-oxide solvent containing from about 1.4% to about 12.5% by weight water and with the amount of water in the solution being between the amounts determined by solving the equations
• B=28.6-2.57 (% water)
• and
• C=21.59-2.59 (% water)
• with B and C being the percent by weight cellulose dissolved in the solvent,
• (2) shaping the resulting solution, and
• (3) precipitating the cellulose from the shaped solution, washing the resulting precipitated shaped, precipitated cellulose substantially free from N,N,-dimethylethanolamine N-oxide and drying the shaped cellulose.

A process for making a shaped cellulose article which comprises

• (1) dissolving cellulose in a N-methylmorpholine N-oxide solvent containing from about 5.5% to about 22% water by weight with the amount of water in the solution being between the amounts determined by solving the equations
• B=34.69-1.695 (% water)
• C=32.38-2.21 (% water)
• with B and C being the percent by weight of cellulose dissolved in the solution,
• (2) shaping the resulting solution, and
• (3) precipitating the cellulose from the shaped solution, washing the resulting precipitated shaped, precipitated cellulose substantially free from N-methylmorpholine N-oxide and drying the shaped cellulose.

A process for making a shaped cellulose article which comprises

• (1) dissolving cellulose in an N,N-dimethylcyclohexylamine N-oxide solvent containing from 0.8% to about 21% by weight water with the amount of water in the solution being between amounts by solving the equations
• A=B+2.63.sqroot.1.05+0.05 (% water).sup.2
• and
• D=C-3.12.sqroot.1.05+0.18 (% water-5.28).sup.2
• with A and D being the percent by weight cellulose dissolved in the solution,
• B=37.45-2.10 (% water)
• and
• C=33.57-3.28 (% water)
• (2) shaping the resulting solution, and
• (3) precipitating the cellulose from the shaped solution, washing the resulting shaped precipitated cellulose substantially free from N,N-dimethylcyclohexylamine N-oxide and drying the shaped precipitated cellulose.

A process for making a shaped cellulose article which comprises

• (1) dissolving cellulose in an N,N-dimethylethanolamine N-oxide containing from about 1.4% to about 12.5% by weight water with the amount of water determined by solving the equations
• A=B+1.23.sqroot.0.61+0.10 (% water-56.66).sup.2
• and
• D=C-2.05.sqroot.1.29+0.58 (% water-4.41).sup.2
• with A and D being the percent by weight of cellulose dissolved in the solution and
• B=28.62- 2.57 (% water)
• C=21.59-2.59 (% water),
• (2) shaping the resulting solution, and
• (3) precipitating the cellulose from the shaped solution, washing the resulting precipitated shaped, precipitated cellulose substantially free from N-methylmorpholine N-oxide and drying the shaped cellulose.