萘系和油系中间相沥青碳纤维性能对比研究

Comparison on the property of the carbon fibers with naphthalene-based and the petroleum-based mesophase pitch

以萘系(SD)及油系(MP)中间相沥青为原料,对比探究两种沥青制备碳纤维的性能差异。采用扫描电镜、X射线衍射仪、纤维强伸度仪和微欧计等手段表征了碳纤维微观结构及力学与导热性能。结果表明:SD沥青灰分126×10^(-6),含有约10%的各向同性组分,制得碳纤维拉伸强度1.13GPa,杨氏模量720GPa,热导率790W/(m·K);MP沥青灰分28×10^(-6),中间相含量100%,制得碳纤维拉伸强度2.21GPa,杨氏模量821GPa,热导率848W/(m·K)。MP碳纤维较SD碳纤维性能更优异的原因在于其具有更大的石墨微晶尺寸、更高的石墨化度及取向度。

The performance differences of the carbon fibers prepared from naphthalene-based(SD)and petroleum-based(MP) mesophase pitch were studied.The microstructures,mechanical properties and thermal conductivity of the carbon fibers were characterized by SEM,XRD,vibrodyn tensile tester and micro ohmmeter.The results shown that the SD pitch had 126 ppm ash content and about 10%isotropic components.The tensile strength,Young’s modulus and thermal conductivity of the SD carbon fibers were 1.13 GPa,720 GPa and 790 W/(m·K),respectively.The MP pitch had 28 ppm ash content and 100% mesophase content.The tensile strength,Young’s modulus and thermal conductivity of the MP carbon fibers were 2.21 GPa,821 GPa and 848 W/(m·K),respectively.The reason why the MP carbon fibers had better properties than the SD carbon fibers was that it had larger graphite microcrystalline size,higher graphitization degree and higher orientation degree.