The Research On Benzoxazine Decorated Silica Nanofiborous Membranes With Flexiblity And Superhydrophobic Property

Inorganic nanofibrous membranes have outstanding performance, such as high temperature resistance, light weight, high strength, good insulation, chemical stability, long service life and so on, due to the applications in high-temperature, sensor, self-cleaning areas and so on. Electrospinning has gained increasing appeal as a versatile technique that creates various inorganic nanofibers, however, the application of inorganic nanofibrous membranes are greatly limited due to its brittleness. Superhydrophobic materials with self-cleaning properties have attracted the best interesting for scientist, which also became the hotspot of surface modification of materials. And the materials with super-hydrophobic surface have bright futrure for various applications both in industrial world and people’s daily life, for example: energy, military, medical, clothing, automobile, etc. In recent years, inorganic nanofibers with superhydrophobic properties have attracted considerable attention, so the research on improving flexibility of inorganic nanofibrous membranes and self-cleaning performance creates a new direction for inorganic fibrous membranes.In this paper, we utilized electrospinning technic to fabricate superhydrophobic silica nanofibrous membranes. The raw materials we used during fabrication are tetraethyl orthosilicate as silicon source, polyvinyl alcohol as polymer carrier. Combined with sol-gel method and calcined technique, we successfully fabricated flexible silica nanofibers. Then we created superhydrophobic silica nanofibrous membranes exhibiting robust thermal stability and flexibility by a facile combination of electrospun silica nanofibers and a novel in situ polymerized fluorinated polybenzoxazine (F-PBZ) functional layer that incorporated SiO2nanoparticles (SiO2NPs). By employing the0.5wt%F-PBZ and2wt%SiO2NPs modification, the pristine hydrophilic silica nanofibrous membranes were endowed with a super-hydrophobicity with WCA up to161°and the sliding angle of5°. Meanwhile, surface morphological studies have revealed that the superhydrophobic of resultant membranes could be manipulated by tuning the surface composition as well as the hierarchical structures. Physical techniques are used to confirm the hierarchical structure of F-PBZ/SiO2NPs modified silica membranes. Cassie theories are also applied to analyze the results of the wetting properties and the f2value of the rough surface is calculated to be0.940.In addition, through the bending rigidity and tensile performance test, we found that the F-PBZ/SiO2NPs modified membranes can facilely bending and recovering, and exhibited good flexibility (0.0127gf cm), and comparable tensile strength (2.19MPa) and strain (5.55%), revealing the excellent flexibility with no cracks appeared during these processes. Meanwhile, the as-prepared membranes exhibited high thermal stability (450℃), suggesting their use as promising materials for a variety of potential applications in high-temperature filtration, self-cleaning coatings, catalyst carriers and oil-water separation etc. In order to expand the application of silica membranes, we fabricate silica/carbon nanofibrous membranes for the first time, its carbon content is10%and it is expected to be applied to the industrial field such as semiconductor, carbon fiber materials and so on.