Syntheses and properties of films from polymer gels based on polymer-metal complexes

Films of poly(2-vinylpyridine) (1), poly(allylamine hydrochloride) (2), poly(5-methyl-2-vinylpyridine) (3) and poly(ethyleneimine) (4) with Ag+, Cu2+, Li+ and Ca2+ salts as well as complex transition metal ions [Fe(Cn)(6)](3-) are prepared at the interface boundaries of immiscible solvents. The polymer/metal salt complexes exhibit highly ordered structures and high thermal stabilities as revealed by reduced viscosity, X-ray diffraction, infrared spectrometry, thermogravimetry, differential thermal analysis as well as measurements of swelling coefficients and electroconductivity. Mole ratios of complex formation of the neat polymers as well as the polymer gels with these salts were found at [polymer]:[salt] = 1, 2, 3 and 4 referring to the repeating units of the polymers. It is suggested that the properties of the films are due to ionic bonds, ion-coordination bonding, coordination bonds and ion-dipole interactions between the functional groups of the polymeric hydro- and organic gels and the metal ions.