Radar-chromatic compatible stealth performance based on adaptive thermochomic materials

Adaptive thermochromic materials can meet the requirements of military dynamic camouflage application in the visible light band. However, a single thermochromic material is not suitable for the development of the battlefield as the requirements of the battlefield multi-band camouflage increase, especially the development of radar-band camouflage. Therefore, thermochromic/radar compatible technology is the issue that needs to be addressed. Adaptive thermochromic microcapsule materials are prepared by in-situ polymerization. The composition of microcapsule is analyzed using SEM, XRD and FTIR. The absorption properties of microcapsule, radar absorbing and thermochromic-radar composite materials are tested using coaxial method. The microcapsule materials are composed of thermochromic complex (fluorescent alkane dyes, bisphenol AF, dodecanol and conjugated color change substances) and urea formaldehyde resin. The corresponding thermochromic coating material includes thermochromic microcapsules, waterborne polyurethane and additives, which are compatible with each other. The microwave absorption test shows that the imaginary part of permittivity and permeability in thermochromic coatings are both zero, which possesses non-electrical and magnetic lossy properties, and does not significantly affect the wave-absorbing performance of the radar-absorbing coatings. The newly developed thermochromic coating material is a transparent to microwave due to the low electromagnetic loss capability. Finally, the thermochromic coating achieves excellent compatibility with radar stealth coatings.