Solvent of cellulose NMMO monohydrate is used as a solvent in the lyocell process to produce lyocell fiber. It dissolves cellulose to form a solution called dope, and the cellulose is reprecipitated in a water bath to produce a fiber. The process is similar but not analogous to the
viscose process. In the viscose process, cellulose is made soluble by conversion to its
xanthate derivatives. With NMMO, cellulose is not derivatized but dissolves to give a homogeneous polymer solution. The resulting fiber is similar to
viscose; this was observed, for example, for
Valonia cellulose microfibrils. Dilution with water causes the cellulose to reprecipitate, i.e. the solvation of cellulose with NMMO is a water sensitive process. Cellulose remains insoluble in most solvents because it has a strong and highly structured intermolecular hydrogen bonding network, which resists common solvents. NMMO breaks the hydrogen bonding network that keeps cellulose insoluble in water and other solvents. Similar solubility has been obtained in a few solvents, particularly a mix of
lithium chloride in
dimethyl acetamide and some hydrophilic
ionic liquids.
Dissolution of scleroproteins Another use of NMMO is in the dissolution of
scleroprotein (found in animal tissue). This dissolution occurs in the crystal areas which are more homogeneous and contain
glycine and
alanine residues with a small number of other residues. How NMMO dissolves these proteins is scarcely studied. Other studies, however, have been done in similar
amide systems (i.e.
hexapeptide). The
hydrogen bonds of the amides can be broken by NMMO. ==Oxidant==