Modified cationic starch composition for removing particles from aqueous dispersions
AssigneeE. I. Du Pont de Nemours and Company
InventorRobert Harvey Moffett
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Abstract
Modified starches prepared by cooking an amphoteric or cationic starch and an anionic, amphoteric, or cationic polyacrylamide have utility as a retention aid in the manufacture of paper.
Claims5
A modified starch prepared by heating at least one amphoteric starch, or cationic starch having a degree of substitution between about 0.01 to 0.2, with at least one polyacrylamide having a molecular weight of at least 500,000 selected from the group consisting of a nonionic polyacrylamide, an amphoteric polyacrylamide, and a cationic polyacrylamide having a degree of substitution between 1% and 80% by weight, said cooking being at a temperature above 80.degree. C. in an aqueous solution having a pH above about 7.0, wherein the weight ratio of starch to polyacrylamide is greater than about 5 to 1, for a time effective to modify said starch.
Dependencies are inferred from the claim text.