A Core-Shell Spherical Silica Molecularly Imprinted Polymer for Efficient Selective Recognition and Adsorption of Dichlorophen

Abstract

A core-shell surface-imprinted polymer was successfully synthesized on the surface of silica spheres by precipitation polymerization. The polymers were used to selectively identify dichlorophen in complex environmental system. The physical-chemical properties of the silica sphere molecularly imprinted polymers were analyzed by scanning electron microscopy and transmission electron microscopy scans characterization. The adsorption properties of core-shell polymers were examined by adsorption isotherms, kinetics and selectivity experiments. The Langmuir adsorption isotherm well fitted the adsorption experimental data, and an increase of temperature enhanced the adsorption capacity. The maximum binding capacity of imprinted polymers reached 72.46 mg g-1 at 318 K. Meanwhile, the adsorption data of binding experiments were well-fitting by the pseudo-second-order equation. Compared with nonimprinted polymer, the imprinted polymer not only has specific selectivity towards dichlorophen but also has higher adsorption performance. Moreover, via the regeneration experiments, it has been demonstrated that the MIPs have certain stability to the adsorption for the target, which provides a good reference for the adsorption of dichlorophen by the imprinted polymer in water.