Electromagnetic interference (EMI) shielding composites and methods of producing the same are described. Carbon nanostructure (CNS) fillers including cross-linked carbon nanotubes (CNTs) and a polymeric encapsulation material are provided, where the carbon nanotubes are encapsulated by the polymeric encapsulation material. The CNS fillers are treated to remove at least a portion of the polymeric encapsulation material. After removing the polymeric encapsulation material, the CNS fillers are mixed with a curable matrix material to obtain EMI shielding composites. In some cases, the removal of the polymeric encapsulation material results in diminished dielectric polarization characteristics for the composites.