Ion-sensitive, water-dispersible polymers, a method of making same and items using same

A polymer formulation comprising:

• an ion-sensitive polymer comprising acrylic acid, NaAMPS, butyl acrylate and 2-ethylhexyl acrylate;
• and
• a non-crosslinking co-binder polymer, wherein the polymer formulation is insoluble in a neutral salt solution containing at least about 1 weight percent salt, said salt comprising one or more monovalent ions;
• and wherein the ion-sensitive polymer is soluble in water containing up to about 200 ppm of one or more multivalent ions.

A polymer formulation comprising:

• an ion-sensitive polymer;
• and
• a non-crosslinking co-binder polymer comprising poly(ethylene-vinyl acetate), wherein the polymer formulation is insoluble in a neutral salt solution containing at least about 1 weight percent salt, said salt comprising one or more monovalent ions;
• and wherein the ion-sensitive polymer is soluble in water containing up to about 200 ppm of one or more multivalent ions.