Morphology, microstructure and mechanical properties of electrospun alumina nanofibers prepared using different polymer templates: A comparative study

摘要

Alumina nanofibers with excellent mechanical properties are an ideal candidate as the reinforcements for composites. In this study, alumina nanofibers were fabricated via electrospinning technique combined with the sol-gel method. Alumina precursor sol was prepared using aluminum nitrate and aluminum isopropoxide. The morphology, microstructure, and mechanical properties of the nanofibers prepared using polyvinyl alcohol, polyvinyl butyral, and polyvinyl pyrrolidone as the polymer templates after calcination at 900 degrees C were investigated and compared. The three fiber samples exhibited continuous structure and the same phase composition of gamma-Al2O3. However, the surface roughness, diameter distributions, densification degrees, crystallization temperatures, grain sizes, tensile strength, and elastic modulus were completely different. Possible mechanisms for these differences were discussed on the basic of the homogeneity of spinning solutions, the decomposition behaviors of polymers, and the quantities and sizes of defects and grains. The findings of this study can help in understanding an often-neglected concept on the important role of polymer categories on the structure and properties of electrospun oxide nanofibers, particularly required with enhanced mechanical properties. (C) 2020 Elsevier B.V. All rights reserved.