With the rapid development of China's aerospace and electronics industries,high-performance pitch-based carbon fibers have attracted more and more attention because of its excellent properties such as high modulus and excellent thermal conductivity.Among these steps,the preparation of mesophase asphalt is the first step in the preparation of high-performance pitch-based carbon fibers.However,due to the complex structure of pitch and more heteroatoms,the properties of mesophase pitch products are not uniform.These facts lead to the situation that the industrial-scale production of spinning grade mesophase pitch has not yet been achieved in China,and thus seriously restricts the development of related industries.In this paper,the formation process and properties of mesophase pitch were reviewed.The composition and molecular structure of coal,petroleum and naphthalene were compared.The effects of complex components in raw pitch on the formation process of mesophase pitch and the common pretreatment methods were described,and the advantages and disadvantages of pretreatment methods were compared.The preparation process,advantages and disadvantages of direct thermal polycondensation,solvent separation,hydrogenation modification,catalytic modification,co-carbon method and other methods were analyzed,and the influencing factors in the formation of mesophase pitch were summarized.Finally,the development prospect of mesophase pitch was prospected,and suggestions were proposed to the current bottleneck problems.Researchers should start from the source of pitch raw materials to explore the influencing rules of their molecular structure and process conditions on the structure of mesophase pitch,and illuminate the proposed mechanism.
mesophase pitchpitch-base carbon fiberraw material pretreatmentpreparation methods