A simple porous gel synthesis method is proposed in this paper. We found that the sequential modification of conventional radical polymerization gives rise to pore formation in acrylamide gels and investigated the parameters that are responsible for controlling the number and the size of pores. Pore formation is dominated by the amount of polymerization initiator (ammonium persulfate), accelerator (N, N, N＇, N＇-tetramethylethylenediamine) and polymerization temperature. The initiator works as a pore nucleus. The accelerator helps the pore growth. However, temperature control is the easiest and the most effective way to create a number of large pores. Especially if the pregel solution is heated to or above 80 degrees C, the pore formation is effectively promoted resulting in an increase in the number of pores and their size. Increase in the volume fraction of macro pores was found to result in the increase in the diffusion coefficients of the solution flowing through gels. (C) 2000 Elsevier Science Ltd. All rights reserved.