Wet strength polymers

A process for the production of a water soluble, cationic, thermosetting polymeric wet strength additive which comprises reacting, in an aqueous medium maintained at a temperature of 20.degree. C. or less, an epihalohydrin and a polymer comprising a backbone formed of repeating segments at least 10% of which comprise an amine group and/or partial salts thereof substantially all of said amine groups being tertiary amine groups pendant from the polymer backbone and having a structure selected from the group consisting of ##STR10## wherein R' is selected from the group consisting of methyl and, where the nitrogen atom bears two R' groups, these together with the nitrogen can form a heterocyclic radical;

• R" is a divalent radical and R'" is a trivalent radical;
• the unattached bond in each amine structure being attached directly to a carbon atom of the polymer backbone;
• the ratio of epihalohydrin groups to tertiary amine groups reacted being not less than the transition ratio for the reaction conditions selected.