Preparation and dual microwave-absorption properties of carboxylic poly(arylene ether nitrile)/Fe3O4 hybrid microspheres

► We prepared poly(arylene ether nitrile)/Fe3O4 hybrid microspheres with hierarchical polymer-inorganic nanostructure. ► A shifting and an immobilized microwave absorbing peaks were observed on the sample. ► Possible mechanism was proposed on the basis of electromagnetic data.