Synthetic naphthalene pitches (SNPs) with isotropy and anisotropy were prepared by a simple thermal polycondensation method to fabricate pitch-based carbon fibers. The structural characteristic, thermal stability, phase-separation behavior, and melt-spinnability of the SNPs and the structural properties of the derived carbon fibers were systematically investigated. The results show that spinnable SNPs with controllable mesophase contents ranging from 0 to 100 vol % and softening points (210-290 °C) could be easily obtained by a nitrogen-bubbling treatment to improve their thermal stability and melt-spinnability by avoiding the phase separation of liquid crystal (LC) in the pitch.
View Article and Find Full Text PDFTwo types of carbon fibers with a large diameter of ∼22 μm, derived from unstirred and vigorously stirred mesophase pitch melts with different liquid crystalline mesophase textures, were prepared by melt-spinning, stabilization, carbonization, and graphitization treatments. The morphology, microstructure, and physical properties of the carbon fibers derived from the two kinds of mesophase precursors after various processes were characterized in detail. The results show that the optical texture (i.
View Article and Find Full Text PDFGraphite nanoplatelets were produced by sonication of thermally reduced graphite oxide produced from three precursor graphites. The thicknesses of the resulting graphite nanoplatlets were measured by X-ray diffraction and transmission electron microscopy. The type and size of the precursor graphite plays an important role in the final graphite nanoplatelet quality.
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