A systematic investigation of acrylic type copolymers was performed for determining their mechanical durability and electrolyte retention, when immersed in various media, including aqueous and organic solutions. Optimization of the chemical and dimensional stability of polymers was possible by electrochemical techniques and swelling/dissolution/evaporation tests. Acrylic acid–acrylonitrile copolymers resistant to aqueous and organic media in a wide pH range have been previously employed in various electrochemical applications, including unconventional reference electrodes. This paper introduces a simple and easy to use system for polymer testing, and highlights the ability of electrochemistry to predict polymer behavior in aqueous and organic solutions. Specially designed gravimetric measurements support the electrochemical characterization of the hydrogel samples. It is shown that open circuit potential against time measurements represent suitable tools for evaluating polymer properties.