Nanocomposite Aerogel Network Featuring High Surface Area and Superinsulation Properties

A nanocomposite strategy for the combination of a polymerized silica precursor, such as polyvinyltrimethoxysilane (P-VTMS), together with electrospun thermoplastic polyurethane (TPU) nanofiber in the aerogel backbone is demonstrated to create effective stress transfer pathways in three-dimensional (3-D) aerogel composites with thermal insulation characteristics and special porous structure. Inspired by the bone architecture in the human body, with large amounts of hard segments and small amounts of soft segments, the 3-D interconnected TPU-embedded P-VTMS-based composite (P-VTMS/TPU) aerogel achieves synergistic strengthening in the nanofiber orientation direction. The sol–gel approach followed by first spinodal decomposition and later binodal decomposition phase separation has been taken in this study to initiate network formation throughout the P-VTMS/TPU backbone to form a 3-D network porous structure. The structure obtained offers full hierarchical multimodal porosity and an unprecedentedly large surface area of 2146 m2 g–1 due to a special approach taken in the sol–gel process in designing the interface between electrospun TPU nanofibers and P-VTMS chains. Owing to the combination of excellent mechanical and thermal insulation properties, the P-VTMS/TPU composite aerogel can be used as a thermal insulation material. Such a hierarchical multimodal porous architecture opens the door to fabricating new 3-D multifunctional and mechanically durable nanocomposite aerogels for flexible devices.