Mesoporous Networks of N-Vinylpyrrolidone with (di)Methacrylates as Precursors of Ecological Molecular Imprinted Polymers

Mesoporous polymer networks were prepared via the cross-linking radical copolymerization of non-toxic hydrophilic N-vinylpyrrolidone (VP) with triethylene glycol dimethacrylate (TEGDM) and poly(ethylene glycol) methyl ester methacrylate (PEGMMA) in bulk, using appropriate soluble and thermodynamically compatible macromolecular additives with a branched structure as porogens. The branched copolymers of various monomer compositions were obtained by radical copolymerization in toluene, controlled by 1-decanethiol, and these materials were characterized by a wide set of physical chemical methods. The specific surface areas and surface morphology of the polymer networks were determined by nitrogen low-temperature adsorption or Rose Bengal (RB) sorption, depending on the copolymer compositions and scanning electron microscopy. The electrochemical properties of RB before and after its encapsulation into a branched VP copolymer were studied on a glassy carbon electrode and the interaction between these substances was observed. Quantum chemical modeling of RB-VP or RB-copolymer complexes has been carried out and sufficiently strong hydrogen bonds were found in these systems. The experimental and modeling data demonstrate the high potency of such mesoporous polymer networks as precursors of molecularly imprinted polymers for the recognition of fluorescent dyes as nanomarkers for biomedical practice.

Adsorption of Selected Heavy and Precious Metals from Simulated Wastewater Using Fabricated Polyacrylonitrile (PAN) and Poly(4-Vinylpyridine) (P4VP) Monoliths

Adsorption has become an attractive method for the extraction and recovery of metals from wastewater effluents. This study involved the fabrication of mesoporous neat polyacrylonitrile (PAN) monoliths and composite polymer monoliths of PAN and poly-4-vinylpyridine (P4VP) as adsorbents for toxic elements (As(V), Cr(VI)) and the recovery of PGMs(Ru(III), Rh(III), Pd(II)) from simulated wastewater solutions. Fabrication of the mesoporous polymer monoliths was conducted using the non-solvent induced phase separation method (NIPS). The monoliths were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and Brunauer–Emmett–Teller (BET). Adsorption studies were conducted using crushed monoliths saturated in 1 mg·L−1 simulated wastewater solutions. Spectroscopic analyses of the resulting filtrates were conducted using inductively coupled plasma-optical emission spectrometry (ICP-OES). In this study, the NIPS method was successfully optimized and mesoporous PAN, as well as composite polymer monoliths, were successfully fabricated. A concentration of 1 mg·L−1 of Ru(III) and Pd(II) was completely adsorbed by both monoliths. The mesoporous composite polymer monoliths exhibited the highest adsorption capacity for Rh(III), As(V), and Cr(VI). The mesoporous polymer monoliths showed great potential for use as wastewater cleaning aids as well as remediators of precious metals.