Carbon nanotube: carbon composites with matrix derived from oxidized mesophase pitch

Abstract

Due to their nanometer-scale dimensions, high mechanicalstrength, and very high thermal and electrical conductivity,carbon nanotubes (CNTs) have attracted much attention tobe recognized as an excellent material choice for nano-composites, in which even a very small amount of CNTscan induce significant changes in the material’s properties[1–4].Since carbon and carbon–carbon composites have manyadvantages, such as excellent mechanical behavior at hightemperatures, low reactivity, high heat capacity, and so on,modern advanced technologies make wide use of thesematerials in different fields, including nuclear reactorwalls, rocket nozzles, battery electrodes, and seal andfriction materials [5–7]. However, the conventional tech-niques to prepare carbon and carbon–carbon compositesare complicated and costly due to the time-consumingprocess, such as liquid phase impregnation and chemicalvapor deposition which are indispensable to obtain high-performance carbon and carbon–carbon composites. Mucheffort has been taken to develop new methods to simplifythe processing and shorten the time of preparing carbon–carbon composite. Most significantly, Naphthalene-derivedsynthetic mesophase pitch (MP) have been recognized asan excellent precursor to the high-performance carbon andgraphite due to their high carbon yield [8–11].However, few researchers try to fabricate the MP basedcomposites reinforced with CNTs because of the difficul-ties in homogeneously distributing CNTs in a MP matrixby traditional methods. In this communication, CNTsreinforced oxidized MP based composites were preparedby one-step self-sintering. The influence of CNTs on themechanical and physical properties on obtained CNTs/carbon derived from oxidized MP composites.The CNTs (multi-walled carbon nanotubes, purity99 wt.%, diameter 20–40 nm) synthesized by chemicalvapor deposition were supplied from Wuhan University ofScience and Technology, China. MP was obtained byMitsubishi Gas Chemical Co., Japan. MWNTs were soni-cated in a bath containing toluene, and then the milled MPwas added to the suspension and hot-mixed at 333 K in theother bath containing toluene under moderate stirring for2 h. Subsequently, the system was moved to a plate anddried at 373 K. The dried compound was ground by a ball-mill into grains of particle size in the range of 2.8–8.2