BAKED AND GRAPHITIZED CARBON

The raw materials used ia the production of manufactured carbon and graphite largely control the ultimate properties and practical appHcations of the final product. This dependence is related to the chemical and physical nature of the carbonization and graphitization processes. 

In most carbon and graphite processes, the initial polymerization reactions occur in the Hquid state. The subsequent stages of crystal growth, heteroatom elimination, and molecular ordering occur in the soHd phase. The result is the development of a three-dimensional graphite stmcture. 

Pitches can be transformed to a mesophase state by further chemical and physical operations. Heat treatment of conventional pitches results in additional aromatic polymeriza tion and the distillation of low molecular weight components. This results in an increase in size and concentration of large planar aromatic molecular species whereupon the precursor pitch is transformed to a mesophase state exhibiting the characteristics of nematic Hquid crystals (1). Additional heat treatment converts the mesophase pitch to an infusible aromatic hydrocarbon polymer designated as coke. 

High carbon yielding resins are sometimes employed as raw material precursors for specialty carbons. Various chemical additives are also used in low concentrations to improve the processabiHty or to control puffing during graphitization. 

Gokes derived from resids or blends of resids with other petroleum feedstocks give high GTE values and are utilized as fillers for aluminum anodes and certain specialty carbon and graphite products. The remaining properties differ depending on the final appHcation. Alow ash content is required for 

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CARBON - CARBON AND ARTIFICIALGRAPHITE - APPLICATIONS OF BAKED AND GRAPHITIZED CARBON] (Vol 4)... 

Processing of baked and graphitized carbon. Properties of manufactured graphite, Appbcations of baked and graphitized carbon. Other forms of carbon and graphite. 

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