High-porosity monolithic composite aerogels of syndiotactic polystyrene (sPS) and poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) containing reduced graphene oxide (r-GO) were prepared and characterized. The composite aerogels obtained by supercritical carbon dioxide (scCO2) extraction of sPS/r-GO and PPO/r-GO gels were characterized by a fibrillar morphology, which ensured good handling properties. The polymer nanoporous crystalline phases obtained within the aerogels led to high surface areas with values up to 440 m2 g-1. The role of r-GO in aerogels was studied in terms of catalytic activity by exploring the oxidation capacity of composite PPO and sPS aerogels toward benzyl alcohol in diluted aqueous solutions. The results showed that, unlike sPS/r-GO aerogels, PPO/r-GO aerogels were capable of absorbing benzyl alcohol from the diluted solutions, and that oxidation of c.a. 50% of the sorbed benzyl alcohol molecules into benzoic acid occurred.
Keywords: aerogels; catalytic oxidation; poly(2,6-dimethyl-1,4-phenylene oxide); reduced graphene oxide; sol-gel process; supercritical carbon dioxide extraction; syndiotactic polystyrene.