values meq h g active polymer using a ph 11 0 endpoint were determined on solid samples of the isolated hydrolyzed terpolymers in the case of aqueous polymer solutions in which the polymer is present in its free acid form no alkali metal salts the solution was freeze dried and then the solid polymer was analyzed for c h and n as well as karl fischer water determination a weighted sample of the solid polymer was also titrated to a ph 11 0 endpoint with standardized aqueous caustic for polymer solutions in their salt or partial salt forms these solutions were ion exchanged through a sulfonic acid resin and then freeze dried the terpolymer of example 1 contained gn gc 12 9 u00d7 10 2 and meq h g 8 1 at ph 11 0 the aqueous polymer solution 418 9 g 45 6 solids of example 1 was heated to reflux with stirring once at reflux a 50 w w sodium hydroxide solution 137 5 g 1 72 mole naoh was added slowly over 30 minutes antifoam agent 5 10 ppm was added and then an ammonia water condensate 137 5 g was distilled from the reaction over 6 hours an amber polymer solution ph 9 2 was obtained which contained approximately 51 solids ion exchanged polymer possessed meq h g 10 3 at ph 11 0 gn gc 8 1 u00d7 10 2 mw 3000 with dispersity of 3 2 maleic anhydride 166 4.