Water-compatible surface molecularly imprinted polymers with synergy of bi-functional monomers for enhanced selective adsorption of bisphenol A from aqueous solution

Water-compatible molecularly imprinted polymers (MIPs) with dual monomer-template interactions were synthesized via the synergy of bi-functional monomers of water-soluble 2-acrylamido-2-methylpropanesulfonic acid (AMPS) and styrene (St) for the selective adsorption of bisphenol A (BPA) from aqueous media using porous graphene oxide as a support. Both hydrogen bonds and π-π interactions are responsible for the adsorption of BPA on the synthesized MIPs. The formation and structure of the MIPs are verified by Fourier transform infrared spectroscopy, thermogravimetric analysis, transmission electron microscopy and dispersion analysis in water. The adsorption results show that the adsorption capacity of MIPs is greatly enhanced by virtue of the synergy of AMPS and St. The MIPs prepared with a molar ratio (AMPS : St) of 2.5 : 2.5 exhibit the highest adsorption capacity (up to 85.7 mg g^-1 at 293 K) toward BPA in aqueous media. The kinetics and isotherm data can be well fitted with the pseudo-second-order kinetic model and the Freundlich isotherm, respectively. Competitive adsorption experiments demonstrate that the synthesized MIPs display excellent selectivity toward BPA against analogue molecules. The MIPs show good recoverability and exhibit excellent adsorption affinity toward BPA even in complex river water. This work provides a versatile approach for the fabrication of high performance MIPs for application in aqueous environments.