Thermosetting precursors materials phenolic resins

Carbon fibers can be produced from a wide variety of precursors in the range from natural materials to various thermoplastic and thermosetting precursors Materials, such as Polyacrylonitrile (PAN), mesophase pitch, petroleum, coal pitches, phenolic resins, polyvinylidene chloride (PVDC), rayon (viscose), etc. [42-43], About 90% of world s total carbon fiber productions are polyacrylonitrile (PAN)-based. To make carbon fibers from PAN precursor, PAN-based fibers are generally subjected to four pyrolysis processes, namely oxidation stabilization, carbonization and graphitiza-tion or activation they will be explained in following sections later [43]. 

Glassy, or vitreous, carbon is a black, shiny, dense, brittle material with a vitreous or glasslike appearance (10,11). It is produced by the controUed pyrolysis of thermosetting resins phenol—formaldehyde and polyurethanes are among the most common precursors. Unlike conventional artificial graphites, glassy carbon has no filler material. The Hquid resin itself becomes the binder. 

In contrast to gas-phase carbonization, most thermosetting resins, such as phenol-formaldehyde and furfuryl alcohol, and also cellulose can be converted to carbon materials by solid-phase carbonization. When the carbonization of most of these precursors proceeds rapidly, the resultant carbon materials become porous. If the carbonization is performed so slowly that the resultant carbonaceous solids can shrink completely, the so-called glass-like carbons are produced, which contain a large number of closed pores. 

The precursor matrix material can be a hydrocarbon gas, a thermoset resin such as a phenolic or furan, or a thermoplastic resin such as a pitch or thermoplastic polymer. 

Pitches are mainly used as binders (i. e. as precursors for binder cokes) but the term binder should include any carbonaceous binder material, for example thermosetting resins such as polylfutfuryl alcohol) or phenolics and similar compounds which may form a char during carbonization. 

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