Abstract: Block carbon materials with high thermal conductivities were prepared from mesophase pitch fibers by using their high preferred orientation of pitch molecular and appropriate thermoplasticity through a hot-pressing method. The conductivities and mechanical properties of carbon materials prepared separately from ribbon-shaped and round-shaped mesophase fibers at different oxidizing temperatures were compared and studied. Results show that compared with the round-shaped mesophase fibers, the ribbon-shaped mesophase fibers have higher preferred orientation and larger contact areas, so they have higher densities and conductivities. The density, bending strength, electrical resistivity and thermal conductivity of carbon materials prepared by using ribbon-shaped fibers oxidized at 260℃ and then sintered at 2800℃ are 2.18g·cm^-3, 118.4MPa, 1.13μΩm and 717W/m·K, respectively.

Key words: mesophase pitch fibers, stabilization, hot-pressing, high thermal conductivity