Complexation of europium ion with poly(methacrylic acid)s and fluorescent property of the complexes

The complexation of europium ion(Eu³⁺) with poly(methacrylic acid) and its copolymers was studied. Poly(methacrylic acid-co-acrylamide) formed the tris(carboxylate)-coordinate Eu complex with extra large overall complexation constant while poly(methacrylic acid)s did the bis-coordinate ones. Transparent and flexible film containing much Eu ion was prepared by casting the complex solution of poly(methacrylic acid-co-methylacrylate). On exposure to ultraviolet light (393 nm), the film relatively strongly fluorescenced a red color based on the tris-coordinate and uniformly dispersed Eu complex.