A personal thermal camouflage material based on nanofibrous polyamide membrane

A spectrally selective nanofibrous PA66/Al/nanoPE composite membrane was fabricated for thermal camouflage of body signature (ε3 - 5μm= 0.09 and ε8 - 14μm= 0.23) and simultaneous heat dissipation outside the detection bands (ε5 - 8μm= 0.55). The synergetic effect of diffusely reflective nanoscale fibrous/porous configuration in PA66 and highly reflective Al metallized nanoPE permits more than 90% spectrally averaged solar reflectance. The characteristic size of the electrospun PA66 membrane centers within the short-wave solar band, resulting in violent Mie scattering that strengthens purple light reflection. The solar heat rejection capability and IR signal shielding performance render PA66/Al/nanoPE optically suitable for personal thermal camouflage in snowy scenario. Both the nanopores in PA66 membrane and the micropores in Al metallized nanoPE provide essential moisture-penetrability for wearing. [Display omitted] •The specific concept of personal thermal camouflage was firstly proposed.•The spectral selectivity based on inherent absorption of PA66 in 5–8 μm makes it easy to be fabricated.•A facile strategy for personal thermal camouflage with simultaneous thermal management.•PA66/Al/nanoPE features both ultraviolet–visible-to-infrared compatible camouflage and wearability required in snowy scenario.•A trade-off between IR transmittance and solar reflectance for the design of PA66 fibrous membrane. Developments in infrared (IR) sensing technology entail thermal camouflage to protect human body from an increased risk of detection. Despite explorations of various IR stealth techniques, achieving personal thermal camouflage with wearability remains a challenge. In this study, we propose a composite membrane consisting of electrospun nanofibrous polyamide-66 (PA66) backed with aluminum (Al) metallized nanoporous polyethylene (nanoPE) to achieve personal thermal camouflage. Our design promises body signature concealment in both detection bands (3–5 μm and 8–14 μm), and surface heat buildup is mitigated simultaneously via intrinsic absorption of PA66 (ɛ5–8 μm = 0.55), resulting in a consistently lower equilibrium temperature compared to non-spectrally-selective contrast samples. With an averaged solar reflectance exceeding 90 %, the skin-simulator temperature decreases over 20 °C compared to the uncovered state at peak solar intensity. Notably, the fabricated purely white PA66/Al/nanoPE strongly scatters ultraviolet light, making it feasible for multiband-com