Solvent system for polysaccharides
AssigneeThe Institute of Paper Chemistry
InventorsDonald C. Johnson, Myron D. Nicholson
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Abstract
Natural or modified polysaccharides are dissolved in a solvent system comprising dimethyl sulfoxide and formaldehyde. The solvent system is particularly suitable for dissolving cellulose due to the fact that cellulose is rapidly dissolved under moderate conditions of temperature and pressure. The dissolved polysaccharides are readily recovered from the solvent system by diluting the solvent system with water or a short chain alcohol.
Claims23
A composition comprising a natural or modified polysaccharide dissolved in a solvent system comprising dimethyl sulfoxide and formaldehyde.
A method for dissolving polysaccharides comprising adding said polysaccharide to a solvent system comprising dimethyl sulfoxide and formaldehyde.
A method for manufacture of methylol cellulose comprising adding cellulose to a solvent system comprising dimethyl sulfoxide and formaldehyde.
A method for manufacture of a cellulose fiber comprising dissolving cellulose in a solvent system comprising dimethyl sulfoxide and formaldehyde, and regenerating a fiber from said celluose solution by injecting a stream of said solution into a regeneration medium selected from the group consisting of an aqueous medium and short chain alcohols.
A method for the manufacture of a cellulose film comprising dissolving cellulose in a solvent system comprising dimethyl sulfoxide and formaldehyde and regenerating a film from said cellulose solution by injecting a film of said solution into a regeneration medium selected from the group consisting of an aqueous medium and short chain alcohols.
A method for making paper comprising treating a cellulose source with a solvent system comprising dimethyl sulfoxide and formaldehyde so as to dissolve cellulose from said source, regenerating said cellulose from said solution by diluting said solution with a regeneration medium selected from the group consisting of an aqueous medium and short chain alcohols, and forming a web from said regenerated cellulose.
Dependencies are inferred from the claim text.