Production of nanostructured materials by electrospinning for obtention of microwave absorbers

Abstract

In a electrospinnig process, polymer mats formed by nanofibers are produced when a polymer solution is subjected to high electrostatic field. The advantages of this process are: large surface area to volume ratio, flexibility in surfaces functionalities, superior mechanical properties. Thus is an attractive process to produce nanostructure materials used in aeronautic field. The main variables of this process are: solution concentration, voltage and working distance. The goal of this project is to produce mats using electrospinning technique to produce radar absorbing materials (RAM) and nanostructure composites used in aeronautic field. The RAM will be produced by electrospinning by two differents routes. The first one will use polymeric thermoplastic polyurethane (TPU)/dicloroacetic acid/ doped polyaniline (PAni-DBSA or PAni-CSA) solutions to obtain conductors nanofibers. The second one will obtain nanostructured composites by electrospinning using poly(ether-imide)/1-methyl-2pyrrolidone/mutiwalled carbon nanotubes (MWNT) solutions. The mats obtained by two routes will be evaluated by thermal behavior (DSC), thermal degradation (TGA), chemical and crystalline structures (FTIR) and morphology (SEM) of the mats. In the TPU/doped PANi and PEI/MWNT mats will be measured electrical conductivity and reflectivity measurements in the microwave range (8 - 12 GHz). (AU)