Novel method of fabricating lightweight thermally insulation fibrous composites for energy saving

Fiberboard (FB) is extensively utilized in heat‐insulating refractory materials owing to its lightweight nature and excellent resistance to high temperatures. Nevertheless, the inadequate mechanical properties and limited dimensional stability of FB hinder its further application. The vacuum filtration was utilized in this study to manufacture inorganically modified insulation FB, incorporating plus fiber/1260 fiber and silica sol as the primary constituents and sepiolite powder (HS) as the modifier. The experimental results show that the fabricated samples exhibited extremely high porosity (75.3%–90.2%) and low thermal conductivity (.063–.15 W m−1 K−1, 200–800°C). The fibers were arranged in a three‐dimensional structure, overlapping with each other, and the silica sol adhered to the fibers, forming a spatial mesh structure through cross‐linking. Importantly, the incorporation of HS was effective in controlling the agglomeration of the silica sol, leading to a more uniform distribution within the fibers. Additionally, the study found that the mechanical properties (high hardness (64–72 HA)) and high‐temperature durability of the FBs were enhanced due to the flocculant modification. This study highlights promising prospects for industrial applications and offers a cost‐effective admixture for modifying and preparing high‐performance FBs, which is expected to see broad adoption in thermal insulation and energy conservation applications.