A Novel Partially Biobased PAN-Lignin Blend as a Potential Carbon Fiber Precursor

Blends of polyacrylonitrile (PAN) and lignin were prepared with three different lignin types by solution blending and solution casting. Among three types of lignin, one type was chosen and different blend concentrations were prepared and casted. The casted blend films were characterized chemically with fourier transform infrared spectroscopy (FTIR), and thermally with thermogravimetric analysis (TGA). The mechanical properties of the blends were measured using dynamic mechanical analysis (DMA). FTIR analysis shows an excellent interaction of PAN and lignin. The interaction of the lignins and PAN was confirmed by TGA analysis. The DMA results reveal that the lignin enhance the mechanical properties of PAN at room temperature and elevated temperatures. The blend structure and morphology were observed using scanning electron microscopy (SEM). SEM images show that excellent polymer blends were prepared. The results show that it is possible to develop a new precursor material with a blend of lignin and PAN. These studies show that the side product of paper and cellulosic bioethanol industries, namely, lignin can be used for new application areas.