Abstract: A multilayer radar-absorbing laminate includes three juxtaposed blocks. A first electrically conductive block is arranged toward the inside of the aircraft in use. A second electromagnetic intermediate absorber block has a layer of electrically non-conductive fiber sheets is permeated by graphene-based nanoplatelets to achieve a periodic and electromagnetically subresonant layer, the conductive layers containing graphene nanoplatelets alternating with non-conductive layers. A third block of electrically non-conductive material is arranged towards the outside and forms part of the outer surface of the aircraft. The second block is produced by depositing on the fiber sheets a suspension of graphene nanoplatelets in a polymeric mixture, with controlled penetration of the graphene nanoplatelets into the fiber sheets. A plurality of dry fiber sheets sprayed with the suspension of graphene nanoplatelets is superimposed.

Abstract: A multilayer radar-absorbing laminate includes three juxtaposed blocks. A first electrically conductive block is arranged toward the inside of the aircraft in use. A second electromagnetic intermediate absorber block has a layer of electrically non-conductive fiber sheets is permeated by graphene-based nanoplatelets to achieve a periodic and electromagnetically subresonant layer, the conductive layers containing graphene nanoplatelets alternating with non-conductive layers. A third block of electrically non-conductive material is arranged towards the outside and forms part of the outer surface of the aircraft. The second block is produced by depositing on the fiber sheets a suspension of graphene nanoplatelets in a polymeric mixture, with controlled penetration of the graphene nanoplatelets into the fiber sheets. A plurality of dry fiber sheets sprayed with the suspension of graphene nanoplatelets is superimposed.

Abstract: A water-based conductive polymeric paint for providing thin conductive, antistatic, and possibly piezoresistive coatings, is produced starting from a liquid water-based polymer or else from a water-based polymeric paint filled with graphene nanoplatelets (GNPs), obtained by exfoliation of expanded graphite. The process envisages the following steps: a) subjecting to thermal expansion commercial graphite intercalation compound (GIC) to obtain known structures such as TEGO, WEG, or expanded graphite (EG), or else using EG of a commercial type; b) dispersing and shredding the TEGO, WEG, or EG structures in water-based paint/polymer possibly diluted with alcohol-water mixture, in variable concentrations according to the desired final properties; c) subjecting the suspension to ultrasonication, where the parameters of the sonication cycle such as temperature of the suspension, energy released, and duration are defined on the basis of the properties of the material that is to be obtained.

Abstract: A process for producing GNP-based polymeric nanocomposites for electromagnetic applications such as shielding and/or absorption of the energy associated to electromagnetic fields envisages a plurality of steps that include: controlled synthesis, for optimizing the morphological and electrical properties thereof, of graphene nanoplatelets (GNPs) to be used as nanofillers in a polymeric matrix; selection of the polymeric matrix so as to optimize its chemical compatibility with the type of GNPs thus obtained; production via the solution-processing technique of GNP-based polymeric nanocomposites with dielectric permittivity and electric conductivity controlled and predictable via the equivalent-effective-medium model by calibrating the parameters of the model for the specific type of polymeric matrix and GNPs used.

Abstract: A process for producing GNP-based polymeric nanocomposites for electromagnetic applications such as shielding and/or absorption of the energy associated to electromagnetic fields envisages a plurality of steps that include: controlled synthesis, for optimizing the morphological and electrical properties thereof, of graphene nanoplatelets (GNPs) to be used as nanofillers in a polymeric matrix; selection of the polymeric matrix so as to optimize its chemical compatibility with the type of GNPs thus obtained; production via the solution-processing technique of GNP-based polymeric nanocomposites with dielectric permittivity and electric conductivity controlled and predictable via the equivalent-effective-medium model by calibrating the parameters of the model for the specific type of polymeric matrix and GNPs used.

Abstract: Multifunctional, radio frequency shielding, transparent in the visible and energy saving film, including an asymmetric and aperiodic superposition of three dielectric or semiconductor (D) layers alternated to two metal (M) nanometric layers, wherein the ratio of the thickness of the outermost metal layer to the inner one is between 1.4 and 1.7. Such a film can be applied on a transparent substrate to make a frequency selective screen having solar absorbance (Ae) always lower than 17% and one of the following combination of performances: Shielding effectiveness (SE) higher than 32 dB from 30 kHz to 18 GHz, with optical visible transmittance (Tv) higher than 75%; Shielding effectiveness higher (SE) than 36 dB from 30 kHz to 18 GHz, with optical visible transmittance (Tv) higher than 65%; Shielding effectiveness (SE) higher than 38 dB from 30 kHz to 18 GHz, with optical visible transmittance (Tv) higher than 50%.