Polymerizable ionic liquid monomers and their corresponding polymers (poly(ionic liquid)s) are created and found to exhibit high absorption of radio frequency electromagnetic radiation, particularly in the microwave and radar bands. These materials are useful for coating objects to make them less reflective of radio frequency radiation and for making objects that absorb radio frequency radiation and are of minimal reflectivity to radio frequency radiation. Free-radical and condensation polymerization approaches are used in the preparation of the poly(ionic liquids).