Highly Hydrophobic SiO ₂ /TiO ₂ Coatings for Thermal Protection: Enhancing Flame Retardancy and Thermal Insulation Performance of Aramid Fabrics

Aramid fabrics are used as substrates, with silica (SiO 2 ) and titanium dioxide (TiO 2 ) particles serving as functional coating materials to enhance the comprehensive performance of flame‐retardant fabrics and to meet diverse application requirements. This study investigates the effects of aramid fabric surface pretreatment, SiO 2 coatings with varying mass fractions, and TiO 2 composite coatings on flame‐retardant thermal‐insulation performance, water resistance, and tensile properties. The results show that the fabric coated with 15% SiO 2 mass fraction exhibits the best thermal‐insulation performance, with a maximum temperature difference of 6 °C between the fabric and the heat source. The SiO 2 /TiO 2 composite coating reduced the thermal conductivity of the fabric by 15.8%. The coated fabric exhibits significantly smaller burn areas than the aramid base fabric, with an increased hydrophobicity of 142.9° and a 22% improvement in tensile strength. The surface coating of aramid fabrics can significantly enhance their performance, providing valuable insights for developing personal protective equipment.