A Novel Approach to Fabricate Polymeric Nanofibrous Aerogels with Embedded Silica Aerogel Particles

This study presents a novel approach to improve the structure of polymeric nanofibrous aerogels by incorporating silica aerogel particles. Para-aramid nanofibers/polyvinyl alcohol (ANFs/PVA) constitute the skeleton of nanofibrous aerogels, and silica aerogel particles derived from methyltrimethoxysilane (MTMS) serve as structural fulcrums embedded in the skeleton of the aerogels. In order to gain an in-depth understanding of the ANFs/PVA/MTMS composite aerogels, we carefully compared them with MTMS aerogels, ANFs aerogels, and ANFs/PVA aerogels. The preparation process and appearance of above four aerogels were clearly demonstrated. Their macroscopic morphology, chemical composition, and porosity were characterized by field emission scanning electron microscope (FE-SEM), attenuated total reflectance-fourier transform infrared spectra (ATR-FTIR), and nitrogen physical adsorption, respectively. The results show that the silica aerogel particles are firmly embedded in the nanofibrous skeleton of aerogels, effectively resisting volume collapse during gelation and supercritical drying, preserving a finer appearance, and forming a stable ternary nanofibrous structure.