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In the realm of military applications, the effective management of ice accumulation on strategic equipment without compromising the integrity of the electromagnetic signal transmission is a perennial challenge. To confront this issue, a revolutionary trilayered material composite known as MPE (metal-polyimide-electric heating layer) has been developed, demonstrating a sophisticated balance between deicing functionality and electromagnetic transparency. The MPE composite is ingeniously architected in a trilayer configuration, comprising a frequency-selective wave-transmissive stratum, an interjacent insulating dielectric interlayer, and an electric heating layer. The former is the result of a pioneering surface grafting modality of keratin, subsequently metallized with a nickel (Ni) coat via a chemical plating technique, which concurrently imparts the composite with a temperature-sensitivity range between −10 and 80 °C. The latter is formulated from a cyanate ester (CE) resin with organic conductive fillers, endowing the material with a high thermal threshold of up to 220 °C. Experimental evaluations of the MPE material have yielded a remarkable 88% transmissivity at the designated resonant frequency, a significant improvement over traditional graphene heating layer. This high level of performance, combined with the material's inherent deicing properties and the capacity for remote control via integrated sensing technology, positions the MPE as a substantial breakthrough for military operations. [ABSTRACT FROM AUTHOR]

Particulate‐filled materials with superior mechanical properties and wave permeability have received extensive research attention in the military industry. To elucidate the role of reinforcement in polymers, γ‐Aminopropyltriethoxysilane (APTES) is used to modify hexagonal boron nitride (h‐BN) nanoparticles, which are then filled into polyphenylene oxide@bisphenol A dicyanate ester composite, exhibiting a 1.46‐fold increase in flexural strength and a dielectric constant of 2.66 at 12 GHz. Finite element analysis is employed to design composite material models, successfully predicting the dielectric properties of composites at different frequencies and reinforcement filling levels. The change in the interface energy induced by the silane coupling agent is quantitatively calculated by molecular dynamics simulation, demonstrating that the modified nanoparticles are conducive to improving the flexural strength. Overall, the predicted dielectric and mechanical properties of composites can be utilized to screen for composites that possess excellent dielectric and mechanical properties, thereby greatly improving efficiency. Highlights: A hexagonal boron nitride/polyphenylene oxide@cyanate ester is prepared.Finite element analysis is employed to predict the dielectric properties.The interface energy is calculated by molecular dynamics simulation.The resin has superior mechanical and dielectric properties. [ABSTRACT FROM AUTHOR]

Flexible and lightweight terahertz (THz) absorbers with high absorption performance are urgently indispensable in the application of foreign substance examination, molecular identification and 6G communication. Herein, cost‐effective approaches of autocatalytic plating and dip‐coating with a series of surface grafting are proposed to construct nickel/Ti3C2Tx (Ni/MXene) decorated polyurethane sponge (PUS) composite. The resultant PUS‐Ni/MXene sample exhibits average THz absorption shielding effectiveness (SEA) and absorption proportion of 42.7 dB and 99.9% from 0.1 to 2.2 THz at a thickness of only 1 mm. The THz SEA can achieve 69.8 dB for PUS‐Ni/MXene sample with 8 mm thickness while the specific SE is over 65.8 (dB cm3 g−1), surpassing most absorbers. To better understand the propagation characteristics of THz waves, the electromagnetic interference SEs and electric field distributions are calculated through finite difference time domain simulation, and verified by experiments. Moreover, the foldable and electrical properties endow the PUS‐Ni/MXene composite with smart pressure sensitivity that is promising for strain monitoring. The optimized PUS‐Ni/MXene sensor exhibits high sensitivity under a relatively small strain. And the outstanding long‐term stability and durability are also proved by 1200 stretching–releasing cycles. The as‐prepared THz absorber with excellent pressure sensing performance demonstrates enormous potential in future military and civilian applications. [ABSTRACT FROM AUTHOR]