Synthesis of high solids-content wet-strength resin
AssigneeHercules Incorporated
InventorWilliam W. Maslanka
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Abstract
Disclosed is an improvement in a method of making a water-soluble epichlorohydrin resin involving reacting epichlorohydrin with a polyaminoamide. The improvement involves preparing the polyaminoamide in the presence of an acid catalyst (low temperature condensation) followed by reaction with epichlorohydrin.
Claims6
A method comprising reacting dicarboxylic acid and a polyalkylenepolyamine in the presence of an acid catalyst to form a polyaminoamide and reacting the polyaminoamide with epichlorohydrin in two stages to form a water-soluble, stable, cationic polyamino-epichlorohydrin wet strength resin, which does not gel when held at 90.degree. F. for 90 days and has a total solids content of at least about 25%, wherein in the first stage the temperature is maintained at from about 30.degree. C. to about 50.degree. C., and in the second stage the temperature is maintained at from about 55.degree. C. to about 75.degree. C. such that the temperature in the second stage is different from the temperature in the first stage, the reaction being carried out in a manner such that the molar ratio of epichlorohydrin to the polyaminoamide is from about 1.7/1 to about 1.9/1.
Dependencies are inferred from the claim text.