One-pot, surfactant-free synthesis of poly(styrene-N,N′-methylenebis (2-propenamide)-acrylic acid) and poly(styrene-N,N′-methylenebis (2-propenamide)-methacrylic acid) microspheres for adsorptive removal of heavy metal ions

Two copolymer microspheres, poly(styrene-N,N '-methylenebis(2-propenamide)-acrylic acid) (PS-MBA-AA) and poly(styrene-N,N '-methylenebis(2-propenamide)-methacrylic acid) (PS-MBA-MAA), were synthesized through a surfactant-free one-pot copolymerization method, rendering them easily prepared. Through the utilization of scanning electron microscopy (SEM), laser particle size analysis, Fourier transform infrared spectroscopy (FTIR), BET adsorption-desorption isotherms, and energy dispersive spectrometry (EDS), the structures of PS-MBA-AA and PS-MBA-MAA were meticulously examined. These analyses provided substantial evidence that the copolymer microspheres possess a relatively uniformity in terms of both particle size and composition. The copolymer microspheres, PS-MBA-AA and PS-MBA-MAA, demonstrate remarkable efficiency in the rapid adsorption of Cu2+, Pb2+, and Cd2+. Notably, they possess the ability to achieve over 80% of their equilibrium adsorption capacity within a mere 10 min. It is worth noting that both types of copolymers exhibit superior adsorption efficacy and anti-coexisting ion interference, particularly in relation to Pb2+ among the three of heavy metal ions.