Ultraviolet-Assisted Extrusion Printing of Photosensitive Resin-Crosslinked Silica Aerogel Composites for Thermal Insulation

Aerogels with tailored geometric features and improved mechanical properties are urgently needed for thermal insulation applications in specific scenarios. However, traditional manufacturing strategies show limitations in the on-demand shaping of aerogels due to their costly and time-consuming fabrication cycles and poor serious impediment fragility. Herein, the ultraviolet (UV)-assisted extrusion printing strategy has been adopted to fabricate photosensitive resin-crosslinked silica (PRCS) aerogel composites. During extrusion printing, there is a synergic process of consecutive ink extrusion deposition and instantaneous photopolymerization of photosensitive resins, displaying a considerable characteristic of solidification-while-printing. The successful implementation for the UV-assisted extrusion printing of PRCS aerogel composites depends on the viscoelasticity and photosensitivity of inks, where the viscoelasticity enables inks to smoothly flow from nozzles and the photosensitivity allows inks to solidify rapidly based on the radical polymerization of photosensitive resin monomers. The UV-assisted extrusion printing strategy has a huge capacity for the rapid manufacturing of aerogel geometries without an additional auxiliary support. After supercritical drying, the 3D-printed PRCS aerogel composites exhibit high shape fidelity and comparable aerogel performances, such as low density (0.256 g·cm–3), high specific surface area (269.3 m2·g–1), high pore volume (1.82 cm3·g–1), improved mechanical properties (compressive strength up to 0.28 MPa), and low thermal conductivity (38.41 mW·m–1·K–1). This work would provide more potential for silica aerogels to satisfy the requirements of shape-dominated insulation applications in specific scenarios.