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(APS) as an oxidant in the aqueous medium,and nanofibers produced by electrospinning . Electrospun nanofiber mats were by treated heat under air atmosphere to be stabilized. Nanofiber production from AN-IA copolymers and suitability of the nanofiber as carbon nanofiber precursor is discussed. Copolymer are characterized using Fourier Transform Infrared - Attenuated Total Reflectance spectrometer (FTIR-ATR), Nuclear Magnetic Resonance Spectroscopy (1H-NMR), differential scanning calorimeter (DSC), thermal gravimetric analysis (TGA) and dynamic mechanical analysis (DMA). The effect of IA content on the spectroscopic and thermal properties of AN-IA copolymers was investigated. Increasing IA content confirmed by spectroscopic methods seriously affects thermal properties which is important for carbon nanofiber production. IA provides a catalytic effect on stabilization process by decreasing initiation cyclization reaction temperature from 202 to 195 oC. Elecrospinning from the AN-IA copolymer solutions in dimethyl foramide (DMF) was performed, morphology of nanofibers was monitored using Scanning Electron Microscopy (SEM). Bead free nanofibers were produced from AN-IA copolymer solutions under same conditions. Average nanofiber diameter decreases from 878±18 to 376±7 nm according to increasing IA content in copolymers. The nanofiber mats produced were treated at high temperature under air atmosphere for oxidative stabilization. Stabilized nanofibers were characterized using FTIR-ATR spectrometer and a new structure was monitored as a result of cyclization reactions. The stabilized nanofibers were also characterized mophologically using SEM. Volume loss occurring after heat treatment calculated based on the nanofiber diameter changes. Consequently, electrospun nanofibers can be suggested as a carbon nanofiber precursor due to suitability for electrospinning and stabilization process. |
