The aqueous solutions of poly(ethylene oxide)-polyacrylic acid, poly(vinyl pyrrolidone)poly(vinyl alcohol), and poly(ethylene oxide)-poly(vinyl alcohol) blends have been studied by ultrasonic, theological, and viscometric techniques. Extensive investigation over a wide range of concentrations, temperatures, compositions, pH, and shear rates indicate the degree of miscibility, extent of interaction between the polymers, and stoichiometry of the polymer complexes formed by the strong interaction between the polymers in solutions. These investigations indicate the miscibility of poly(ethylene oxide)-polyacrylic acid and poly(ethylene oxide)-poly(vinyl pyrrolidone) blends and the immiscibility of poly(ethylene oxide)-poly( vinyl alcohol) blends in conformity with other reported investigations.