Interconnectivity of Macroporous Hydrogels Prepared via Graphene Oxide-Stabilized Pickering High Internal Phase Emulsions.

Interconnected macroporous poly(acrylic acid) (PAA) hydrogels are prepared via oil-in-water (o/w) Pickering high internal phase emulsion (HIPE) templates stabilized by graphene oxide (GO). The amphiphilicity of GO is adjusted by slight modification with cetyltrimethylammonium bromide (CTAB). The morphology of macroporous PAA is observed by a field-emission scanning electron microscope (FE-SEM). The gas permeability is characterized to evaluate the interconnectivity of polymer foams. The pore and pore throat size can be tailored by varying the wettability and concentration of GO. The selective adsorption toward dyes of PAA hydrogels is proved. Macroporous PAA hydrogels with an open-cell structure show enhanced adsorption behavior of both methylene blue (MB) and copper(II) ions.