Efficient and stable solid acid catalysts synthesized from sulfonation of swelling mesoporous polydivinylbenzenes

Efficient and stable solid acid catalysts, sulfonic groups functional swelling mesoporous polydivinylbenzenes (PDVB-x-SO3Hs), were synthesized from sulfonation of swelling mesoporous polydivinylbenzenes (PDVB-xs) by chlorosulfonic acid in CH2Cl2. Nitrogen adsorption–desorption isotherms showed that PDVB-x-SO3Hs have high surface area and abundant mesoporosity. Elemental analysis and acid–base titration techniques showed that PDVB-x-SO3Hs have high concentration of sulfonic groups. Esterifications of acetic acid with cyclohexanol, hexanoic acid with ethanol, lauric acid with ethanol and acylation of anisole with acetyl chloride showed that PDVB-x-SO3Hs are more active than arenesulfonic, propyl-sulfonic groups functional mesoporous silicas (SBA-15-Ar-SO3H, SBA-15-Pr-SO3H) and strongly acidic ion-exchange resin (Amberlyst 15). The superior performance of PDVB-x-SO3Hs is attributed to their unique features including large surface area, abundance of mesoporosity as well as high content of sulfonic groups.