Abstract: Using aerogel as a heat- insulating functional component, several types of aerogel insulation felts with double-sided grille structure of different specifications were developed by template coating method.The air permeability and thermal protection performance of the double- sided grid aerogel insulation felt were measured and characterized by the digital air permeability meter and the hot plate method respectively，then the thermal protection mechanism was analyzed.The results show that the addition of aerogel and the optimized design of the fabric structure significantly improve the thermal protection performance of the fire protection thermal insulation fabric, and decrease the reduction of air permeability to the greatest extent. Moreover, the study shows that there is no significant correlation between the air permeability and the thickness of the coating, but the air permeability is directly proportional to the gap length of the grid.Among them, the aerogel coating with a thickness of 0.5 mm and a width of 2.5 mm has the best comprehensive performance, the air permeability is 138.91 mm/s, and the temperature difference between the inside and outside was increased by nearly 40 ℃ compared with uncoated fabric.

Key words: fire protective clothing, aerogel, double-sided grille, air permeability, thermal protection