Nanoporous polyanilines (PANIs) have attracted attention due to well-defined molecular structures and chemical versatility, which also complicate the mechanisms of interaction between metal ions and PANI. To further understand the complexation with metal ions, tailor-made nanoporous PANIs were synthesized with self-stabilized dispersion polymerization (SSDP) using the poly(vinyl alcohol) (PVA) and various alkaline metals for suitable target metal complexation. The effective complexation results for the removal of Cr ions were obtained by the nanoporous PANI derived from a PVA/Li system. The synthesized tailor-made PANI-emeraldine base (EB) was easily oxidized by a Cr(VI) oxidant resulting in an pernigraniline form with a rigid polymer template and effective metal ion binding sites, and then the reduced form of Cr(III) can be complexed with the resulting PANI. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.