Economical fabrication of multifunctional UHMWPE fibre composite paper for electromagnetic shielding, thermal camouflage and green heating

To address the complex integrated challenges of electromagnetic interference (EMI), infrared (IR) detection exposure, and extreme cold environments, it is critical to develop materials that integrate EMI shielding, IR stealth, and active heating functions. However, the infrared stealth function is in stark contradiction to the electromagnetic/optical heating effect, and it is difficult to control the thickness of the material. Therefore, finding solutions to the aforementioned problems poses a challenge for both the materials and the structure. In this study, a multi-layer structure composite paper of UHMWPE/Fe 3 O 4 /MXene is fabricated. By enhancing spatial steric hindrance and regulating buoyancy, we increase the contact distance between ultra-high molecular weight polyethylene (UHMWPE) fibres, reduce their buoyancy in aqueous media, and achieve their natural sedimentation and uniform dispersion. The PE paper exhibits EMI shielding effectiveness (EMI SE) of up to 29.6 dB (in the X band) due to the differentiated interlayer impedance of the multifunctional structure. The mechanical strength of the MXene layer is enhanced by the fibre layer, resulting in a paper tensile strength of 14.87 MPa. The dense MXene layers arranged along the surface orientation have enhanced the IR stealth performance of the PE paper (maximum temperature difference of 35.23 °C from a 70 °C heat source) and photothermal capability (peak temperature of 81.5 °C for infrared light and 58.5 °C for natural light). All the functions are achieved through 0.44 mm. It holds significant potential to serve as a promising material for the multifunctional protection of both electronic devices and personnel.