Multiscale Manufacturing of Recyclable Polyimide Composite Aerogels.

Mitigating embodied emissions is becoming increasingly crucial as the energy supply shifts toward more sustainable sources. Bio-based materials present a potentially more sustainable alternative to synthetic polymers; however, it often do not yet match the performance of synthetic materials. Given the ongoing reliance on high-performance, high-environmental-impact materials, it is essential to ensure their complete recyclability. Aerogels, recognized by IUPAC as one of the top ten emerging technologies, are witnessing rapid market growth in thermal insulation and thermal protection applications. In certain applications, synthetic and composite aerogels exhibit superior performance, particularly under high temperatures. Here, molecular simulation tools are employed to elucidate the interaction forces between polymers and solvents, develop a recycling strategy for polyimide-based aerogels, and demonstrate their application in thermal protection for firefighter textiles and thermal runaway protection for Li-ion battery packs. These composites are engineered for disassembly, allowing for the complete recovery of starting materials without any degradation of components after multiple recycling cycles. The recyclable composites can be fabricated using various manufacturing techniques to produce fibers (1D), membranes (2D), and complex structures (3D). This unique combination of outstanding performance and excellent recyclability facilitates the sustainable utilization of aerogels in protective clothing, electric mobility, consumer goods, and aeronautics.