Regulated assembly of PBO nanofibers as aerogel fibers for thermal insulation and electromagnetic shielding

Aerogel fibers with combined features of aerogel structure and large aspect ratio are a promising technical solution for high-performance thermal insulation textiles. However, the current aerogel fibers suffer from the drawbacks of insufficient strength, complicated process, and low temperature tolerance. Herein, we demonstrate robust mechanical Poly (p-phenylene benzobisoxazole) (PBO) aerogel fibers with PBO nanofibers (PBONFs) as building blocks via a regulable spinning assembly strategy. As a result, PBONFs are packed tightly in the sheath and highly porous nanofibrous network in the core. Benefitting from the unique structure, the PBOAFs presented high strength (13.57 MPa), high specific surface area (269.33 m2 g−1), ultralow thermal conductivity (26 mWm−1K−1), and superior thermal insulation performance under extreme conditions (−40 °C–300 °C). Furthermore, PBONFs functioned as lightweight and high-efficient electromagnetic shielding fabric, via in situ polymerization polypyrrole, with a value exceeding 30 dB in the X-band. Results indicate the PBO aerogel fibers' great potential as next-generation protective fabric for thermal insulation and electromagnet.