Abstract: Fiber-based aerogels have attracted significant interest because of their low cost,multifunctionality, and low density. However, issues like poor structural processability and fragile mechanical properties greatly restrict their practical use. This study proposes a synergistic physical entanglement-freezedrying method to create renewable fiber-based aerogels that are ultralight, highly elastic, and offer excellent thermal insulation. By integrating skin-core structured polyester fibers (SPFs) into a nanocellulose solution and solidifying the structure through freeze-drying, a hierarchical fiber-based aerogel was formed. After functionalization with organosilane, the bicomponent polyester/nanocellulose aerogel exhibited outstanding comprehensive properties, including remarkable hydrophobicity (contact angle: 128.5°±0.2°), strong mechanical performance, and very low thermal conductivity (0.037 5 W/(m·K)).

Key words: nanofiber aerogel; polyester fiber; thermal insulation; environmentally friendly