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Ellen Kohn

Reinhard Stober

Dietmar Bischoff

A process for the dry cationization of polyvinyl alcohol (PVA) by reaction of alkylidene epoxides with PVA in alkaline medium in the presence of water, in which the reaction mixture contains 11 to 30 weight % of water, based on its total amount, and 1 to 4 weight % of an alkali metal or alkaline earth metal hydroxide or alkaline earth metal oxide, based on the quantity of PVA. As the cationizing agent there are used alkylidene epoxides or their mixtures having the general formula: ##STR1## wherein n=1, 2 or, 3, R.sup.1, R.sup.2 and R.sup.3 represent the same or different alkyl residues having 1 to 18 carbon atoms or R.sup.1 represents the benzyl or --C.sub.2 H.sub.4 OH, and X.sup.- denotes chloride, bromide, sulfate or acetate. Instead of alkylidene epoxides, the corresponding halohydrins, e.g. chlorohydrin or bromohydrin, can be used.

Process for dry cationization of polyvinyl alcohol

A process for the preparation of cationized polyvinyl alcohol (PVA) by reaction of alkylidene epoxides with PVA in alkaline medium in the presence of water, in which the reaction mixture contains 11 to 30 weight % of water, based on its total amount, and 1 to 4 weight % of an alkali metal or alkaline earth metal hydroxide or alkaline earth metal oxide, based on the quantity of PVA. As the cationizing agent there are used alkylidene epoxides or their mixtures having the general formula ##STR1## wherein n - 1, 2 or 3, R.sub.1, R.sub.2 and R.sub.3 represent the same or different alkyl residues having 1 to 18 carbon atoms or R.sub.1 represents the benzyl or --C.sub.2 H.sub.4 OH, and X.sup.- denotes chloride, bromide, sulfate or acetate.

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Munich, Georgia

Ellen Kohn