Abstract:

Interpenetrating polydivinylbenzene/poly(methyl acrylate) polymeric macroporous network(PDVB/PMA IPN) was prepared by sequential suspension polymerization method. By converting PMA into PAA, a hydrophobic-hydrophilic macroporous polydivinylbenzene/poly(acrylic acid) IPN(PDVB/PAA IPN) was achieved. The adsorption thermodynamics and adsorption kinetics of the hydrophobic-hydrophilic IPN were studied. The pore structure, weak acid exchange capacity, water retention capacity and swelling ratio of PDVB/PAA IPN resin were measured. The study focused on the adsorption isotherms of phenylamine at different temperatures. Isosteric adsorption enthalpy, Gibbs free energy and entropy can be calculated according to thermodynamic functions. Infrared spectra results showed that PDVB/PAA IPN resin was successfully synthesized. Compared with the PDVB, PDVB/PMA IPN resin, the BET surface area and pore volume of the PDVB/PAA IPN resin were decreased significantly. The weak acid exchange capacity was 1.91 mmol/g. The water retention capacity was 62.73％. The adsorption of phenylamine was found to be an exothermic process. The experiments of the swelling ratio and the static desorption revealed that the hydrophobic PDVB part in PDVB/PAA IPN resin was responsible for the adsorption of phenylamine through hydrophobic interaction, while the hydrophilic PAA part could adsorb phenylamine by means of hydrogen bondings. The adsorption of phenylamine onto the PDVB/PAA IPN resin reached the equilibrium after 90 min. The adsorption kinetic data of phenylamine fitted the first order rate equation. The intrapartical diffusion of phenylamine was the main rate-controlling step. Adsorption rate was also affected by the film diffusion. The adsorption kinetic data of phenylamine could be described by HSDM model.

Key words: Hydrophobic-hydrophilic, PDVB/PAA IPN, phenylamine, Adsorption