High‐Performance Nanocomposite Aerogels From Halloysite Nanotubes and Polyarylate Nanofibers for Thermal‐Acoustic and Electromagnetic Applications

ABSTRACT Nanofiber‐based aerogels, although characterized by low density and high porosity, face limitations in thermal‐acoustic applications due to inadequate property synergy, restricted multifunctionality, and the complexity of fabrication processes. This research addresses these challenges by developing a nanocomposite aerogel composed of halloysite nanotubes and liquid crystalline polyarylate nanofibers (HNT/PAR NCA) through environmentally friendly freeze‐drying and heat treatment methods. The high aspect ratio of PAR nanofibers facilitates the formation of a self‐entangled three‐dimensional framework, effectively encapsulating the HNT fillers. The thermoplastic nature of PAR allows for thermal welding at fiber interfaces and with HNT, resulting in a stable, interlocked structure without the need for external binders. This micro‐nano porous architecture enhances structural stability, reduces thermal conductivity, improves sound absorption, and preserves electromagnetic transparency. With 20 wt% HNT, the HNT/PAR NCA exhibited a thermal conductivity of 0.036 W m −1 K −1 , just 48% of commercial PU foam's value. At 100°C, its surface temperature was 44.4°C after 90 s and stabilized at 26.4°C at −6°C. It achieved a sound absorption coefficient of 0.79 and a noise reduction coefficient of 0.45, improving by 155% and 137% over commercial PU foam, respectively. A 5 mm thick sample reduced sound pressure by 10.4 dB.