Monolithic aerogels based on poly(2,6-diphenyl-1,4-phenylene oxide) and syndiotactic polystyrene.

Molecular sorption behavior of amorphous and semicrystalline samples based on poly(2,6-diphenyl-1,4-phenylene oxide) (PPPO) has been compared. Fully amorphous PPPO powders, as obtained by supercritical carbon dioxide (scCO2) extraction of concentrated solutions, present uptake of pollutants much higher than for commercial sorbent materials based on semicrystalline PPPO (Tenax TA). Robust monolithic aerogels with good handling characteristics can be easily obtained by solvent extraction by scCO2 from gels including PPPO blends with syndiotactic polystyrene (s-PS). These monolithic PPPO/s-PS aerogels present many advantages as sorbent materials with respect to both amorphous and semicrystalline PPPO powders. In fact, besides the obvious advantages in terms of easier and safer handling, the new monolithic aerogels present higher surface areas and equilibrium guest uptakes.