Imprinted Polysilsesquioxanes for the Enhanced Recognition of Metal Ions

Imprinting techniques have been used to synthesize organic−inorganic hybrid polymers with ionic recognition characteristics. 1,2-bis(triethoxysilyl)ethane (BTSE) monomers were copolymerized with metal ion complexes of N -[3-(trimethoxysilyl)propyl]ethylenediamine ((TMS)en) in the presence of supramolecular assemblies of cetyltrimethylammonium chloride (CTAC), via room temperature, hydrolytic, sol−gel procedures. Subsequent extraction of the surfactant and metal ions results in a porous material with a high affinity for the metal ion template. Selective sorbents have been synthesized for Cu(II), Ni(II), and Zn(II). Adsorption studies indicate that these materials preferentially sequester the metal ion template from mixed solutions and exhibit fast uptake kinetics. These materials have been characterized by nitrogen gas adsorption, small-angle X-ray scattering, solid state 13 C NMR, and UV−visible spectroscopy.