Starch sulfomaleate half-esters, a method for their preparation and their use to prepare starch disulfosuccinate half-esters
AssigneeNational Starch and Chemical Corporation
InventorsMartin M. Tessler, Otto B. Wurzburg, Teresa A. Dirscherl
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Abstract
Novel starch sulfomaleate half-esters are prepared by reacting a starch base or a modified starch containing anionic, cationic, and/or nonionic substituent groups with about 0.1 to 100% by weight of sulfomaleic anhydride or its salts. The reaction is carried out at pH 5-9 and at 5.degree.-90.degree. C. for 0.5-20 hours or at pH 9-11 and at 5.degree.-30.degree. C. for about 0.5-3 hours. The starch sulfomaleates may be reacted with sulfurous acid or its acid salts (e.g. sodium bisulfite) to form the novel starch disulfosuccinate.
Claims14
A starch derivative, comprising a starch sulfomaleate of the general structure:
- ##EQU5## or mixtures of (i) and (ii);
- wherein St--O-- represents a starch molecule or a modified starch molecule, M is a cation, and n is the valence number of M.
A starch derivative, comprising a starch disulfossuccinate of the general structure:
- ##EQU6## or mixtures of (iii), (iv), and (v);
- wherein St--O-- represents a starch molecule or a modified starch molecule, M is a cation, and n is the valence number of M.
Dependencies are inferred from the claim text.