Ultralight and robust aerogels based on nanochitin towards water-resistant thermal insulators

• Published in: Carbohydrate polymers 2020-11, Vol.248, p.116755-116755, Article 116755
• Main Authors: Yan, Youxian, Ge, Fang, Qin, Yu, Ruan, Mengya, Guo, Zeyong, He, Chuanxin, Wang, Zhongkai
• Format: Article
• Language: English
• Subjects: Aerogel; Mechanical robust; Nanochitin; Self-assembly; Thermal insulation
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2020.116755

Ultralight aerogels with tunable density (10−50 mg/cm3) and high porosity (96.3 %–99 %) are prepared from renewable nanochitin. The resultant nanochitin-based aerogels present hydrophobic behavior (contact angle >130°), robust mechanical stiffness (the specific compression modulus of 65 MPa cm3/g) and low thermal conductivity (30.5–35.8 mW/m K). This work may provide a new opportunity to fabricate lightweight, strong environmentally friendly and applicable high-performance thermal insulators using biomass. [Display omitted] •Ultralight chitin aerogels with tunable density (10−50 mg/cm3) are produced.•They present robust mechanical property and low thermal conductivity.•Silylation modification improves their water resistance and mechanical performance. The development of lightweight, strong and high-performance thermal insulators from renewable biomass are highly desired for sustainable development. Here, ultralight aerogels based on renewable nanochitin with outstanding mechanical properties, excellent water-resistant, and promising thermal insulation properties are fabricated. The pristine nanochitin aerogels (PNCAs) assembled from mechanically strong carboxylated chitin nanorods are firstly prepared through acid-induced gelation and supercritical drying. The resultant PNCAs present tunable density (10−50 mg/cm3) and strong mechanical stiffness (the specific compression modulus of 30.2 MPa cm3/g) combining with low thermal conductivity (27.2 mW/m K). After a facile silylation modification, the silylated nanochitin aerogels (SNCAs) exhibit hydrophobic behavior (contact angle >130°), improved compression performance (the specific compression modulus of 65 MPa cm3/g), and promising thermal insulation property (30.5–35.8 mW/m K). Moreover, the silylated aerogel shows a negligible loss of mechanical performance when exposed to water for 12 h at 35 °C.