This paper describes the preparation and characterization of poly(2,6-dimethyl-1,4-phenylene)oxide (PPO) highly porous monolithic aerogels with a hydrophobic nanoporous-crystalline phase and a hydrophilic sulfonated amorphous phase. The sulfonated aerogels were obtained by the sulfonation of PPO physical gels, followed by the supercritical CO2 extraction of solvents. WAXD and FTIR analysis showed that the nanoporous-crystalline phase was preserved for a degree of sulfonation up to c.a. 35%, allowing a highly volatile organic compound (VOC) sorption capacity. The sulfonated PPO aerogels exhibited a high water sorption capacity, with a water uptake of up to 500 wt%, and faster VOC sorption kinetics from water with respect to unsulfonated aerogels.
Keywords: aerogel; poly(2,6-dimethyl-1,4-phenylene)oxide; solid-state sulfonation.