Nanocomposite microgels that selectively adsorb and release halogen compounds were developed. These nanocomposite microgels consist of poly(2-methoxyethyl acrylate) (pMEA) and a poly(oligo ethylene, glycol methacrylate) hydrogel matrix. Therefore, the methoxy groups of the former are crucial for the halogen bonding, while the presence of the latter adds colloidal stability and allows controlled uptake/release of the halogen compounds. Such nano composite microgels may not only be used as dispersed carriers, but also In films and columnar formations. Thug, these unprecedented polymer/polymer nanocomposite microgels resolve a variety of problems associated with, e.g., the removal of halogen compounds from wastewater, or with the delivery of halogen-containing drugs.