| Mesocarbon microbeads (abbreviated to MCMB) is a new pitch-based carbon precursor due to its unique shape and structure. Much work has been focused on MCMB since it was discovered in 1961 and it has been widely used to lithium ion secondary batteries, high-density isotropic carbon, super-high surface area active carbon etc. These researches and developments enriched greatly the theory of liquid-phase carbonization and directed to further development. The presence of B resin (Toluene Insoluble-Pyridine Soluble fraction called self-binder) on the surface of MCMB endowed the seif-sinterability of MCMB owing to the fluidity of P resin when pressed or heat-treated. High-density isotropic carbon would be obtained from MCMB through hot-pressing and carbonization without any additional binder. This processing is simple, cheap and timesaving, compared with those conventional methods, and has become an important technology to manufacture high-density isotropic carbon. The control over the sinterability of MCMB as well as its sintering mechanism has been one of the most interesting project of carbon science and technology.In this paper, MCMB was prepared from Refined Petroleum Residue (abbreviated to RPR) and medium coal tar pitch through heat polycondensation and solvent extraction. The sinterability of MCMB was controlled by extraction times or oxidation temperature and time, thus MCMB was hot pressed and then carbonized to obtain high-density isotropic carbon. The influences of B resin content, oxidation temperature and time of MCMB on the properties of isotropic carbon such as weight loss, volume shrinkage, bulk density ;ind bending strength etc were investigated in detail. On the basis of change results of weight loss, volume shrinkage, conductivity and bending strength of carbon pieces with heating temperature, the model of self-sintering mechanism of MCMB was proposed according to the results of Scanning ElectronicMicroscopy, Thermogravimetric Analysis(TGA), X-Ray Diffraction(XRD) and Raman spectroscopy. Finally, C/C composite with good performance was prepared using MCMB as the matrix, indicating the feasibility of this method to manufacture C/C composite.High-density isotropic carbon pieces were obtained through hot-pressing and carbonization of MCMB with different B resin content and its properties were studied . The results indicated that B resin content was of important effect on the self-sinterability of MCMB, and influenced the properties of resulting materials such as density and bending strength etc. When B resin content was too high, the carbon pieces tended to distort during carbonization, and when B resin content was too low, the binding forces between MCMB was weak, which all resulted in the decrease of the properties of materials. High-density isotropic carbon with the best properties was obtained when B resin content of MMCB was 8.9wt%, and the density and the bending strength was 1.76 g/cm3, and 31.9MPa respectively.The sinterabilty of MCMB could also be controlled through the oxidation treatment in the air. The results show that petroleum-based MCMB need lower oxidation temperature, while coal tar pitch-based MCMB need higher ones for the optimal self-sinterability. Moreover, the properties of isotropic carbon showed the tendency of first increasing and then declining with the elongation of oxidation time. The isotropic carbon with density and bending strength of 1.71 g/cm3 and 83.1MPa respectively from the petroleum-based MCMB was obtained when oxidized at 250C for 40min, while coal tar pitch-based MCMB was 300C-45min with density and bending strength being 1.64 g/cm3 and 99.5MPa. From the results above, it is indicated that pitch-based MCMB was better precursor for high strength isotropic carbon material due to the difference of structure of RPR and coal tar pitch.The influences of heat-treatment temperature ranging from 300C to 1100C on the properties of carbon pieces from MCMB such as weight loss, volume shrinkage, density, conductivity and bending strength etc were studied in detail. T...
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