Hydrolysis of Esters with Polymer Sulfonic Acids

I. Hydrolysis of Linear Aliphatic Monoesters with Polystyrene Sulfonic Acid

Abstract

Hydrolysis of linear aliphatic monoesters was carried out in aqueous solutions with hydrochloric acid or polystyrene sulfonic acids (PS-S) of various degrees of sulfonation as catalysts and the rates of hydrolysis were compared. As far as the comparison was done under the equivalent acid concentrations the catalytic activities of PS-S were generally greater than that of HCl, and increased with the decrease of their sulfonation degrees and the solubility of the esters in water. Rise of reaction temperature and an addition of acetone to the reaction mixture reduced considerably the effectiveness of PS-S. On the basis of these results, it seems that the hydrogen ion is concentrated in the neigbourhood of polymer molecules and the hydrophobic interaction between PS-S and the ester increases the local concentration of the ester in the neigbourhood of polymer molecules.