Poly (acrylonitrile - co -1-vinylimidazole): A new melt processable carbon fiber precursor

Acrylonitrile/1-vinylimidazole (AN/VIM) copolymers containing various mol% of VIM were synthesized by free radical solution polymerization. The copolymers were characterized by Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy, 1H NMR spectroscopy, gel permeation chromatography (GPC) and differential scanning calorimetry (DSC). Char yields of the copolymers were 40-48% as determined by thermogravimetric analysis (TGA) while gel fractions were found to be 90-99% depending upon the composition, temperature and time. The complex viscosity of the precursor copolymers was measured as a function of composition and temperature. 82/18 mol% of AN/VIM copolymer based carbon fiber precursor was successfully processed by solvent-free melt spinning at 192 °C and the melt-spun fiber was characterized by DSC, ATR-IR, and X-ray Diffraction (XRD).