A series of novel rapidly responsive P( AAEA/AMPS/AA) hydrogels with interco nnected superpo rous structure were synthesi zed by foaming dispersion copolyme rization using 4-acetyl acryloyl ethyl acetate ( AAEA)
2-acrylamide-2-methylpro panesulfonic acid ( AMPS) and acrylic acid ( AA) as monomers. Results showed that when the mole fraction of initiator and that of crosslinker were 2.5 % and 0.6 % respectively
the equilibrium swelling ratios were highest. The hydrogels had uniform and interconnected porous structure when using the saturated solution of sodium carbo nate ( Na
2
CO
3
) as foaming agents
and pores formed in the surface of hydrogel could increase the contact area between hydrogels and solvent after being treated by ethanol. The hydrogels could reach their swelling and deswelling equilibrium within 20s
and they had favo rable ion sensitivity and repeatability be tween distilled water and NaCl solution.