大直径中间相沥青基炭纤维的制备研究

以萘系中间相沥青为原料,通过熔融纺丝和随后的预氧化、炭化以及石墨化处理制备了中间相沥青基圆形炭纤维.研究了热处理温度对纤维导电性能和力学性能的影响,并采用红外光谱仪、元素分析仪、扫描电子显微镜和X射线衍射仪对纤维的组成、形貌和微观结构进行了表征.研究结果表明：纤维在预氧化时形成的羟基、酰基等含氧官能团在随后的炭化、石墨化处理过程中消失；随热处理温度的升高,石墨微晶逐渐发育、长大,并沿纤维轴向高度取向,纤维的电阻率不断降低,力学性能不断增强；3 000℃石墨化纤维电阻率为1.3μΩ·m,对应的强度和模量值为1.6GPa和380 GPa.

Preparation of mesophase pitch-based carbon fiber with large diameter

Using a naphthalene derived mesophase pitch as a raw material, mesophase （AR） pitch-based round carbon fibers were prepared by melt-spinning, oxidation stabilization as well as further carbonization and graphitization processes, respectively. The influences of heat treatment temperatures （HTTs） on the electrical and mechanical properties of carbon fibers were investigated. Its compositions, morphologies and microstructure were characterized by IR spectroscopy, elemental analyses, scanning electron microscope, and X-ray diffraction （XRD）. The results show that the hydroxyl and aeyl functional groups formed during the oxidizing stabilization process are removed by subsequent carbonization treatment. Increasing with the heat-treatment temperature, graphite crystallite in the carbon fibers gradually develops, grows up and displays perfect crystal orientation along the longitudinal direction of fibers, its electrical resistivity continuously declines, and its mechanical properties are continuously improved. The electrical resistivity, tensile strength and modulus of carbon fibers prepared at 3 000℃ are 1.3 μΩ·m, 1.6GPa and 380GPa, respectively.