A method for the separation of low and high molecular weight fractions of linear ethylene poly maleic and / or - copolymers

摘要

Type A gelatin is modified by reaction at a pH of from 3 to 8.5 and temperature from 25 DEG to 90 DEG C. with sufficient polycarboxylic acid compound selected from succinic, maleic, phthalic, citraconic, itaconic, and aconitic anhydrides and succinyl and fumaryl chlorides, and mixtures thereof, to lower the isoelectric p point of said type A gelatin within the pH range of 4.0 to 5.5. Type B gelatin may be mixed with the type A gelatin during the reaction. The reaction mixture may contain 2 to 3% by weight of the type A gelatin of succinic anhydride or maleic anhydride, or 3.5 to 5% by weight of succinyl chloride. The type A gelatin may be deionized after or deanionized prior to the reaction. The modified type A gelatin may be added to a gelatin solution to stabilize the viscosity loss of the solution from prolonged heating at 60 DEG C., or may be used in the formation of a hard gelatin capsule or marshmallow.ALSO:Marshmallow formulations and hard gelatin capsules contain a type A gelatin modified by reaction at a pH of from 3 to 8.5 and temperature from 25 DEG to 90 DEG C. with sufficient polycarboxylic acid compound selected from succinic, maleic, phthalic, citraconic, itaconic and aconitic anhydrides and succinyl and fumaryl chlorides, and mixtures thereof, to lower the isoelectric point of said type A gelatin within the pH range of 4.0 to 5.5. Type B gelatin may be mixed with type A gelatin during the reaction. The type A gelatin may be deionized after or deanionized prior to the reaction. The modified type A gelatin may be mixed with conventional type A gelatin in the manufacture of capsules.