Synthesis and characterization of polyvinyl amine–SiO2–Al2O3 as a new and inexpensive organic–inorganic hybrid basic catalyst

Composite polyvinyl amine–SiO2–Al2O3 (PVAm–SiO2–Al2O3) was prepared using two different methods (in situ and impregnation). The physical and chemical properties of the catalysts were investigated by FT-IR, XRD, BET, SEM and TGA techniques. The catalytic activity of the composites was compared for the Knoevenagel condensation reaction in the presence of water as solvent. The catalytic activity of the catalyst prepared by in situ method was higher than that of the impregnated method. The catalyst was easily prepared from inexpensive materials showing a considerable level of reusability besides very good activity.