Catalytic activity of hybrid iron oxide silver nanoparticles in methyl methacrylate polymerization

Abstract

One of the challenges in the preparation of poly(methyl methacrylate) (PMMA) is to develop new catalytic systems with improved efficiency. A hybrid iron oxide silver catalyst holds promise in solving this issue. Catalysts were prepared at room temperature by a two-step technique. First, iron oxide nanoparticles were prepared by the reduction of FeCl3 using sodium borohydride (NaBH4) at room temperature. Second, magnetic nanoparticles doped with a series of Ag nanoparticles (Ag, Ag/3 –amino propyltriethoxysilane (APTES) and Ag/poly(ethyleneimine) (PEI)). The prepared catalysts were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), dynamic light scattering (DLS), scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDX), and Fourier-transform infrared spectroscopy (FTIR). The catalytic activity of Fe, Ag/Fe, PEI–Ag/Fe, and APTES–Ag/Fe in methyl methacrylate (MMA) polymerization was investigated in the presence of O2, N2, NaHSO3, and benzoyl peroxide in bulk or solution conditions. The produced polymer was characterized by gel permeation chromatography (GPC) and proton nuclear magnetic resonance spectroscopy (1HNMR). The structures of PEI–Ag/Fe and APTES–Ag/Fe are assumed. The conversion efficiency was 100%, 100%, 97.6%, and 99.1% using Fe, Ag/Fe, PEI–Ag/Fe, and APTES–Ag/Fe catalysts at the optimum conditions, respectively. Hybrid iron oxide silver nanoparticles are promising catalysts for PMMA preparation. © 2020 by the authors. Licensee MDPI, Basel, Switzerland.