Effect of Ionic Liquid Structure on the Melt Processability of Polyacrylonitrile (PAN) Fibers

The production of high strength carbon fibers is an energy intensive process where a significant cost involves the wet or dry spinning of polyacrylonitrile (PAN) fiber precursors. Melt spinning PAN fibers would allow for significant reduction in production cost and production hazards. Ionic liquids (ILs) are an attractive fiber processing medium due to their negligible vapor pressure and low toxicity. In addition, they are carbon forming precursors; upon carbonization residual ILs can enhance carbon yield although primarily useful for plasticized melt spinning of PAN precursor fibers. In this research, we investigated the influence of the molecular structure of the ILs and the control of the plasticizing interactions with PAN during melt spinning. The structure, thermal and mechanical properties of the melt spun PAN fibers were obtained by a combination of various characterization methods, such as differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), Fourier transform infrared spectro...