欧阳婷 陈云博 蒋朝 李果

摘   要：中间相沥青在碳化过程中轻组分不断逸出而发生剧烈膨胀，对以其为黏结剂或基体的碳纤维增强复合材料的界面结合性能有显著影响. 利用TG、XRD和SEM等考察了预氧化条件对碳纤维的热稳定性、碳收率、晶体结构和纤维在乙醇水溶液中分散性的影响规律. 从多个预氧化条件中甄选出以270 ℃保温150 min处理的氧化纤维进行碳化条件影响规律的考察. 利用光学显微镜观察发现700～900 ℃碳化的碳纤维直径变化最显著. 利用FTIR和SEM考察不同碳化温度碳纤维与中间相沥青黏结剂制备的碳黏碳纤维网络体的界面相容性. 结果表明，500 ℃碳化的碳纤维与碳质黏结剂的结合紧密，结点平滑无裂纹，具有优异的界面相容性. 500 ℃碳化的碳纤维与中间相沥青黏结剂在后续碳化处理中共同经历碳结构的主要形成阶段，可改善黏结界面，为提高材料性能提供有效途径.

关键词：中间相沥青;预氧化;碳纤维;复合材料;碳纤维网络体

中图分类号：TB332                                文献标志码：A

Effect of Heat Treatment on Interfacial Compatibility of

Mesophase Pitch - Carbon Fiber Binding

OUYANG Ting1，2?，CHEN Yunbo1，JIANG Zhao1，LI Guo1，2

（1. College of Materials Science and Engineering，Hunan University，Changsha 410082，China;

2. Hunan Provincial Key Laboratory for Advanced Carbon Materials and Applied Technology，Changsha 410082，China）

Abstract：Mesophase pitch suffers severe expansion during carbonization due to the escape of light components， which significantly affect the interfacial compatibility of  carbon fiber reinforced composites where mesophase pitch is used as binders or matrix. In this work， the effects of oxidation treatment on pitch fibers thermal stability，carbon yield， crystalline structure and dispersivity in alcohol aqueous solution were analyzed by TG， XRD and SEM. The fibers oxidized at 270 ℃ for 150 min were then selected for further study on the influence of carbonization conditions. It was found that the diameter of carbon fibers（CFs） carbonized at 700～900 ℃ changed significantly as observed by the optical microscope. The influence of carbonization temperature on interface compatibility between carbon fiber and mesophase pitch binders in carbon bonded carbon fiber composites was investigated using FTIR and SEM. The results show that the interface between CF  carbonization at 500 ℃ and binder was smooth and crack-free， showing excellent interface compatibility. As CFs carbonized at 500 ℃ and mesophase pitch can experience a similar high-temperature carbonization process， during which a major transformation process of carbon structure occurs， the composite can be obtained with enhanced interfacial properties.

Key words：mesophase pitch;preoxidation;carbon fibers;composite;carbon fiber network

中間相沥青是一类由多种稠环芳烃组成的特殊大分子混合物，光学各向异性，是制备多种高性能碳材料的重要前驱体，如碳微球、针状焦、泡沫碳、碳纤维（Carbon Fiber，CF）等[1-4]. 其中CF的高取向性和石墨结构使其拥有轻质、高强、高模和极高的导热系数，常用于制备高导热和高模量复合材料[5-6].

作为优异的碳质前驱体，中间相沥青具有良好的高温流动性、高碳收率、易石墨化性，因而也被用作高导热碳/碳复合材……