Facile preparation for gelatin/hydroxyethyl cellulose‐SiO2 composite aerogel with good mechanical strength, heat insulation, and water resistance

Abstract The advanced thermal insulation materials with low cost and high mechanical properties play an important role in transport packaging and thermal protection fields. An inorganic/organic composite aerogel was prepared through hydrogen bonds and chemical crosslinking among silica aerogel particles, gelatin (GA), and hydroxyethyl cellulose (HEC). The as‐prepared GA/HEC‐SiO 2 composite aerogels were characterized by compression tests, scanning electron microscopy, Fourier transform infrared, thermogravimetric analyzer, and contact angle tests to investigate the chemical composition and physical structure. The GA/HEC‐SiO 2 composite aerogels exhibited a strong mechanical strength (0.53–4.01 MPa), a high compression modulus (1.33–11.52 MPa), a lower volume density (0.035–0.081 g/cm 3 ), thermal conductivity as low as 0.035 W/[m K]), a porosity of more than 93%, and hydrophobic angle as high as 150.01° after hydrophobic modification. These results indicate that biopolymer composite aerogels embedded with SiO 2 aerogel particles display a bright future in thermal insulation.