In the search for new materials to separate 2,4-dinitrophenol (DNP) from 2,4-dinitroanisole (DNAN), we have focused on the polymer design and synthesis of novel porous poly(amide-sulfonamide) (PASA) containing both repeated amide and sulfonamide functional groups from the reaction of m-chlorosulfonylbenzoyl chloride with 4,4′-diamino diphenyl sulfone in DMAc, using low-temperature solution polymerization. The structure and thermal property of the PASA were characterized by BET, SEM, FT-IR,1H NMR, XRD, TGA; the selective removal of 2,4-DNP from DNAN solution was analysed by adsorption experiments. The BET, SEM and XRD results showed that the PASA with a porous morphology is nearly amorphous; the molecular weight of the polymer was investigated by GPC. Thermogravimetric analysis indicated that the reasonably high temperature recorded (>380 °C) before a 5% weight loss occurred. The removal rate of 2,4-DNP solution was 54.11% at 30 °C. [ABSTRACT FROM AUTHOR]