Dual-Gradient Impedance/Insulation Structured Polyimide Nonwoven Fabric for Multi-Band Compatible Stealth

Xinwei Tang ¹, Wei Hong ¹, Hongmiao Gao ¹

⁰The Key Laboratory of Synthetic and Biological Colloids, Ministry of Education, School of Chemical and Material Engineering, International Joint Research Laboratory for Nano Energy Composites, Jiangnan University, Wuxi, 214122, Jiangsu, People's Republic of China.

Nano-Micro Letters +

|

January 4, 2026

View abstract on PubMed

Summary

A novel polyimide-based fabric offers advanced electromagnetic interference shielding and stealth capabilities. This material achieves dual-gradient impedance and insulation for superior radar and infrared concealment, even at high temperatures.

Area Of Science

Materials Science
Nanotechnology
Defense Technology

Background

Developing advanced materials for military applications is crucial for enhancing operational effectiveness.
Electromagnetic interference (EMI) shielding, radar, and infrared stealth materials require high performance and compatibility.
Existing stealth materials often face limitations in high-temperature environments.

Purpose Of The Study

To design and prepare a novel conductive/magnetic polyimide-based nonwoven fabric (PFN<sub>y</sub>) for military applications.
To achieve hierarchical dual-gradient impedance/insulation structures for enhanced stealth.
To evaluate the material's high-temperature resistant radar and infrared stealth performance.

Main Methods

Fabrication of PFN<sub>y</sub> via alkali treatment, Fe<sup>3+</sup> ion exchange, thermal reduction, and electroless nickel plating.
Construction of a hierarchical dual-gradient impedance/insulation structure by stacking PFN<sub>y</sub> layers.
Characterization of EMI shielding, radar stealth, infrared stealth, and high-temperature resistance.

Main Results

The PFN<sub>y</sub> exhibited adjustable impedance/insulation characteristics through controlled Fe<sub>3</sub>O<sub>4</sub> growth and Ni plating.
The dual-gradient structure effectively introduced and dissipated electromagnetic waves, yielding outstanding EMI shielding and radar stealth.
The material demonstrated excellent infrared stealth by inhibiting thermal radiation and maintained performance at high temperatures due to strong interfacial interactions.

Conclusions

The developed PFN<sub>y</sub> material with a hierarchical dual-gradient structure offers superior EMI shielding, radar, and infrared stealth.
The material exhibits excellent high-temperature resistance, making it suitable for demanding military camouflage.
This research presents a promising candidate for advanced military applications requiring multi-spectrum stealth capabilities.

Keywords:

Electroless plating Electromagnetic interference shielding Infrared stealth Polyimide Radar stealth

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