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Aerogel materials are used in various fields, but there is a shortage of aerogel materials with an excellent combination of mechanical properties, thermal stability, and easy preparation. In this study, polyimide aerogel materials with superior mechanical properties, thermal stability, and low thermal conductivity were prepared by forming a double-gel system in the liquid phase. The amino-modified gel, prepared by coating SiO2 nano-microspheres with GO through a modified sol-gel method (SiO2@GO-NH2), was subsequently homogeneously dispersed with PAA wet gel in water to form a double-gel system. The construction of a double-gel system enabled the PI aerogel to shape a unique honeycomb porous structure and a multi-layered interface of PI/SiO2/GO. The final obtained PI aerogel possessed effective thermal conductivity (0.0309 W/m·K) and a high specific modulus (46.19 m2/s2). In addition, the high thermal stability (543.80 °C in Ar atmosphere) and the ability to retain properties under heat treatment proved its durability in high thermal environments. The hydrophobicity (131.55°) proves its resistance to water from the environment. The excellent performance of this PI aerogel and its durability in thermal working environments make it possible to be applied in varied industrial and research fields, such as construction and energy, where heat and thermal insulation are required.

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With the development of science and technology and electronic industry, electromagnetic wave pollution has become the fifth largest pollution in the world today, so it is very important to develop a material with good wave absorbing properties. In this study, polyaniline was loaded onto the surface of carbon nanotubes (CNTs) bundles in Buckypaper by electropolymerization, and epoxy resin was used as the matrix to prepare a polyaniline (PANI)/Buckypaper/EP composite absorber with integrated structure and function. The research shows that the CNTs are prepared into Buckypaper with a three‐dimensional porous structure by vacuum filtration. This three‐dimensional porous structure ensures that CNTs can be added at a high content and uniformly dispersed in epoxy resin. PANI adjusts the impedance matching of Buckypaper and adds more loss mechanisms. Under the optimal matching thickness of 1.5 mm, the optimal reflection loss reaches −29.31 dB, and the absorption bandwidth is 3.12 GHz. At the same time, the interaction between the π–π noncovalent bond of PANI and the delocalized π electrons on the surface of CNTs improves the mechanical strength of Buckypaper. The tensile strength reached 42.17 MPa, an increase of 92.82% compared with pure BP/EP. The research in this article is expected to provide a feasible idea for the preparation of structure–function integrated materials.