MPP-based carbon fibers

Figure 5.16 The mean interlayer spacing of PAN based and MPP based carbon fibers in comparison with a well graphitizing coke. Source Reprinted with permission from Fitzer E, PAN-based carbon fibers-present state and trend of the technology from the viewpoint of possibilities and limits to influence and control the fiber properties by the process parameters, Carbon, 27(5), 621-645, 1989. Copyright 1989, Elsevier.

Note Such high values of Young s modulus can be achieved most readily in MESOPHASE PITCH BASED CARBON FIBERS (MPP based carbon fibers). 

MESOPHASE PITCH BASED CARBON FIBERS (MPP BASED CARBON FIBERS) are CARBON FIBERS obtained from MESOGENIC PITCH after it has been transformed into MESOPHASE PITCH (MPP) at least during the process of spinning, after the spun MESOPHASE PITCH fibers have been made non-fusible (stabilized) and carbonized. 

Note RAYON-BASED CARBON FIBERS have a more isotropic structure than similarly heat treated polyacrylonitrile (PAN) or MESOPHASE PITCH (MPP) BASED CARBON FIBERS. Their Young s modulus values are, therefore, drastically lower (< 100 GPa). RAYON BASED CARBON FIBERS can be transformed into anisotropic CARBON FIBERS with high strength... 

The term pitch-based carbon fibers comprises the isotropic pitch-based carbon fibers as well as the anisotropic MPP-based carbon fibers. The isotropic type belongs to the carbon fibers type LM and is mainly used as filler in polymers and insulation materials and for similar applications. The anisotropic type (MPP-based carbon fibers) belongs to the carbon fibers type HM and is used mainly for reinforcement purposes due to its high Young s modulus value. 

See carbon fibers type HM, carbon fibers type LM, isotropic pitch-based carbon fibers, MPP-based carbon fibers... 

Figure 19. Tensile behavior of carbon fibers, based on polyacrylonitrile (PAN) or mesophase pitch (MPP), and compared with polyaramide and glass fibers (48).

---