HOMOGENEOUS AND SUPPORTED TITANATES AS CATALYSTS FOR TRANSESTERIFICATION OF ACRYLIC ESTERS

The transesterification of methylmethacrylate with 1-dodecanol has bee n studied by using Bronsted acid and Lewis acid type catalysts either for homogeneous or heterogeneous systems. Initial rates studies in a b atch reactor lead to a greater efficiency for the Lewis acid catalysts (soluble or supported titanates). The activity of the supported catal yst can be linked to the molecular association of the titanates during the fixation on the silica support, the existence of monomeric specie s corresponding to the most important activity. The nature of the supp ort has also an influence: for the same density of titanium atoms, a s maller surface area leads to a better efficiency.