Direct Synthesis of Polyimide Curly Nanofibrous Aerogels for High‐Performance Thermal Insulation Under Extreme Temperature

Abstract

Maintaining human body temperature is one of the basic needs for living, which requires high‐performance thermal insulation materials to prevent heat exchange with external environment. However, the most widely used fibrous thermal insulation materials always suffer from the heavy weight, weak mechanical property, and moderate capacity to suppress heat transfer, resulting in limited personal cold and thermal protection performance. Here, an ultralight, mechanically robust, and thermally insulating polyimide (PI) aerogel is directly synthesized via constructing 3D interlocked curly nanofibrous networks during electrospinning. Controlling the solution/water molecule interaction enables the rapid phase inversion of charged jets, while the multiple jets are ejected by regulating charge density of the fluids, thus synergistically allowing numerous curly nanofibers to interlock and cross‐link with each other to form porous aerogel structure. The resulted PI aerogel integrates the ultralight property with density of 2.4 mg cm−3, extreme temperature tolerance (mechanical robustness over −196 to 300 °C), and thermal insulation performance with ultralow thermal conductivity of 22.4 mW m−1 K−1, providing an ideal candidate to keep human thermal comfort under extreme temperature. This work can provide a source of inspiration for the design and development of nanofibrous aerogels for various applications.

Fabrication of a core–shell nanofibrous wound dressing with an antioxidant effect on skin injury

“…We applied electrospinning technology to design wound dressing materials with bioactive and biocompatible properties, as it is a practical and mature technology for producing nanofibers with porous structures. 11,12 The electrospun nanofiber dressings have a three-dimensional grid structure, allowing water and oxygen exchange. 13,14 Moreover, the electrospun nanofiber dressing with a bioactive substance could simulate the extracellular matrix and promote cell adhesion and migration on the fiber surface.…”