Magnetic Vinylphenyl Boronic Acid Microparticles for Surface Catalytic Performance in Esterification of Propionic Acid with Methanol

Magnetic vinylphenyl boronic acid microparticles, poly(ethylene glycol dimethacrylate-vinylphenyl boronic acid) [m-poly(EGDMA-VPBA)], produced by suspension polymerization, was found to be efficient solid acid catalyst for the esterification of methanol and propionic acid. Characterization techniques such as FT-IR, Elemental analyses, ICP-AES, ESR, SEM and N2 sorption showed that both of Fe3O4 and H2SO4 are bonded to the polymer successfully. Esterification was studied for different molar percentages of H2SO4 at temperature range of 50-70 oC. The apparent activation energy was found to be 27.7 kj.mol-1 for 10% H2SO4 doped m-poly(EGDMA-VPBA). Combining of strong acid H2SO4 with m-poly(EGDMA-VPBA), leads to materials with different functional properties. In addition, H2SO4 species could be introduced into the structure as acid centers, therefore this micro-dimensional catalyst has potential candidate for applications in the catalytic esterifications such as propionic acid with methanol.