The surface morphologies of the AC/PPSU/PEI/PEG composite membranes were observed by FE-SEM.
The blending of AC particles,PEI polymers, and a pore-formation agent PEG with the PPSU casting solution can improve the porous structure of PPSU membranes.
As shown in Figs. 3 and 4, all the membranes exhibited similar asymmetric and sponge-like structures.
The pore size distributions in the wall and on the surface of the sponge-like structures were increased along with
the AC contents in a casting solution.
When 1 wt.% of AC particles was added, the AC incorporation could be observed within the macrovoids
and it induced broadening (Fig. 4), thus increasing membrane structure porosity.
The porosity of 1 wt.% of the AC/PPSU/PEI/PEG composite membrane was larger than that of 0.25 wt.% of the AC/PPSU/PEI/PEG composite membrane.