Functionalized boron nitride aerogel composite material as well as preparation method and application thereof

The invention discloses a functionalized boron nitride aerogel composite material as well as a preparation method and application thereof, and belongs to the technical field of boron nitride aerogel. The preparation method comprises the following specific steps: step 1, preparing functionalized boron nitride nanosheets, and adding an aqueous dispersion of the functionalized boron nitride nanosheets into a polyvinyl alcohol aqueous solution; 2, solidifying the functionalized boron nitride/polyvinyl alcohol aqueous solution by adopting a low-temperature freezing method to obtain a mixed solid; and step 3, sublimating water in the mixed solid by adopting a freeze-drying method so as to prepare the boron nitride aerogel. Functionalized boron nitride nanosheets are introduced to form effective connection with a polyvinyl alcohol skeleton structure, so that the mechanical property and the heat insulation property of the composite aerogel are enhanced. The mechanical property of the prepared aerogel composite materi