An insulated container having an outer vessel and an inner vessel, containing an insulative fluid formed from a mixture of water and a water absorptive poly(potassium acrylate) polymer in the approximate ratio of 50:1 (cc:g), that can be heated or cooled and that reduces heat transfer from hot or cold beverages, particularly well-suited for use in connection with both hot and cold beverages, to maintain the liquid either hot or cold.