Evaluation on Thermal Protection Performance of TiO2@ATO Coated Aramid Nonwoven

Aramid nonwoven (AN), with lightweight and flexible features, is highly attractive as a thermal insulation material to prevent or minimize skin burn damage. However, it has a finite protective effect due to the restriction of the polymer material and the surface hairiness of nonwoven fabrics. This study aimed to introduce different shapes of TiO2 particles coated with Sn(Sb)O2 (ATO) so as to promote protective performance by taking advantage of the high refraction of TiO2@ATO in the visible light (Vis) and near-infrared (NIR) range. It is demonstrated that, compared with AN, the thermal protection effect of the obtained TiO2@ATO-coated AN (TiO2@ATO/AN) was significantly improved owing to the excellent radiation and conduction heat-shielding performance of the TiO2@ATO coating. The micro-morphology, Vis–NIR spectral features, heat-shielding performances, and thermal protective performance (TPP) values of different composite nonwovens were measured to explore their thermal insulation mechanisms and performances. Compared with pristine AN and AN coated with commercial nano-ATO (ATO/AN), the heating rate of TiO2@ATO/AN heated using an alcohol lamp was much lower. The maximum TPP values of TiO2@ATO/AN were enhanced to 1457.874 kW·s/m2, while the values for AN and ATO/AN were only 432.23 kW·s/m2 and 945.054 kW·s/m2, respectively. This study proposes an attractive solution for protecting fabrics against heat damage and opens up tremendous possibilities for heat-resistant nonwoven materials applied in the thermal protection field.