Carbon fibers melt-spinning

Edie, D. D. and Dunham, M. G., Melt spinning pitch-based carbon fibers. Carbon, 1989, 27(5), 647 655. 

Vapor grown carbon fiber (VGCF) is the descriptive name of a class of carbon fiber which is distinctively different from other types of carbon fiber in its method of production, its unique physical characteristics, and the prospect of low cost fabrication. Simply stated, this type of carbon fiber is synthesized from the pyrolysis of hydrocarbons or carbon monoxide in the gaseous state, in the presence of a catalyst in contrast to a melt-spinning process common to other types of carbon fiber. 

A considerable amount of subsequent research and process development has been carried out to produce silicon carbide with a reduced level of excess carbon via processes that allow more facile cross-linking.2 -32 Several hundred papers and patents on this topic exist in the literature, and only a few examples will be mentioned here. One process development involves the slurry spinning of fibers in place of melt spinning.33 In this process, silicon carbide powder, made by a conventional industrial process, is dispersed in a solution of carbosilanes in toluene. The syrupy paste is spun into fibers and then pyrolyzed to silicon carbide. These fibers are reported to be stable at 1,500 °C for 120 hours. 

High modulus C-fibers from special pitch 1st step polymerization > 300 C to mcsophase pitch 2nd step melt spinning 3rd step oxidative crosslinking 4th step inert carbonization at 1500 to 3000"C... 

The as-synthesized polymer is soluble in pentane and hexane but does not melt upon heating preventing the preparation of complex shapes by melt-processing such as melt-spinning. However, its solubility offers potential for the preparation of BN matrices and coatings for ceramic fibers through pyrolysis up to 1000 °C in an ammonia atmosphere. A significant improvement of the oxidation resistance of carbon fibers has been observed with BN matrices. 

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