Structure and Properties of Carbon Fibers

The surface properties of carbon fibers are intimately related to the internal structure of the fiber itself, which needs to be understood if the surface properties are to be modified for specific end applications. Carbon fibers have been made from a number of different precursors, including polyacrylonitrile (PAN), rayon (cellulose) and mesophase pitch. The majority of commercial carbon fibers currently produced are based on PAN, while those based on rayon and pitch are produced in very limited quantities for special applications. Therefore, the discussion of fiber surface treatments in this section is mostly related to PAN-based carbon fibers, unless otherwise specified. 

This means that it is necessary to have a high degree of preferred orientation of hexagonal planes along the fiber axis if a high modulus is desired. To improve the orientation of graphite crystals, various kinds of thermal and stretching treatments. 

Property High strength (HS, Type If) Intermediate modulus (IM, Type II) High modulus (HM. Type III) 

At the end of the fiber manufacturing processes, a size is normally applied to the carbon fibers for use as reinforcement of PMCs. Sizing of carbon fiber involves application of an organic film to protect the fiber during fabrication into structural parts and components. The amount of sizing varies between 0.5-1.5 wt% of the fiber depending on the type and application of fibers. Sizes are intended  

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Low density, carbon fiber-carbon binder composites are fabricated from a variety of carbon fibers, including fibers derived from rayon, polyacrylonitrile (PAN), isotropic pitch, and mesophase pitch. The manufacture, structure, and properties of carbon fibers have been thoroughly reviewed elsewhere [3] and. therefore, are... 

Pitch is a "pseudo solution" of a wide variety of different generic classes of hydrocarbons ranging from paraffins at one extreme to very highly aromatic species at the other. By using the Theory of Solubility for Non-Electrolytes, specific fractions can be isolated from a pitch by properly selecting a solvent system and extraction conditions. "Tailored" precursors for carbon fiber and other carbon products, such as carbon/carbon matrices and bulk graphites, can thus be obtained. The technique of extraction, the characteristics of different precursors, and the structure and properties of carbon fiber and composites made from solvent extracted precursors will be discussed. 

Edie DD, The effect of processing on the structure and properties of carbon fibers. Carbon, 36(4), 345-362, 1998. 

D. J. Johnson, Structure and properties of carbon fibres, in Carbon Fibers Filaments and Composites, J. L. Figueiredo etal., eds., 119-146, KluwerAcad. Publ., Dordrecht NL (1990). 

Johnson DJ, Structure and properties of carbon fibres, Figueiredo JL, Bernardo CA, Baker RTK, Hiittinger KJ eds.. Carbon Fibers, Filaments and Composites, Kluwer Academic Publishers, Dordrecht, 1989. 

Structure and properties of carbon nanotube-polymer fibers using melt spinning... 

Because of their unique blend of properties, composites reinforced with high performance carbon fibers find use in many structural applications. However, it is possible to produce carbon fibers with very different properties, depending on the precursor used and processing conditions employed. Commercially, continuous high performance carbon fibers currently are formed from two precursor fibers, polyacrylonitrile (PAN) and mesophase pitch. The PAN-based carbon fiber dominates the ultra-high strength, high temperature fiber market (and represents about 90% of the total carbon fiber production), while the mesophase pitch fibers can achieve stiffnesses and thermal conductivities unsurpassed by any other continuous fiber. This chapter compares the processes, structures, and properties of these two classes of fibers. 

Hamada, T., Nishida, T., Sajiki, Y. and Matsumoto, M., Structures and physical properties of carbon fibers from coal tar mesophase pitch, J Mat Res, 1987, 2(6), 850 857. 

The direct linking of carbon nanotubes to graphite and the continuity in synthesis, structure and properties between carbon nanotubes and vapor grown carbon fibers is reviewed by the present leaders of this area, Professor M. Endo, H. Kroto, and co-workers. Further insight into the growth mechanism is presented in the article by Colbert and Smalley. New synthesis methods leading to enhanced production... 

Detailed accounts of fibers and carbon-carbon composites can be found in several recently published books [1-5]. Here, details of novel carbon fibers and their composites are reported. The manufacture and applications of adsorbent carbon fibers are discussed in Chapter 3. Active carbon fibers are an attractive adsorbent because their small diameters (typically 6-20 pm) offer a kinetic advantage over granular activated carbons whose dimensions are typically 1-5 mm. Moreover, active carbon fibers contain a large volume of mesopores and micropores. Current and emerging applications of active carbon fibers are discussed. The manufacture, structure and properties of high performance fibers are reviewed in Chapter 4, whereas the manufacture and properties of vapor grown fibers and their composites are reported in Chapter 5. Low density (porous) carbon fiber composites have novel properties that make them uniquely suited for certain applications. The properties and applications of novel low density composites developed at Oak Ridge National Laboratory are reported in Chapter 6. 

Vilatela JJ, Khare R, Windle AH. The hierarchical structure and properties of multifunctional carbon nanotube fiber composites. Carbon. 2012 Mar 50(3) 1227-34. 

Bell, 1989 Rhee and Bell, 1991), random copolymers of methyl acrylate and acrylonitrile were directly polymerized onto the carbon fiber surface. Dimethyl formamide, dimethyl sulfoxide and distilled water proved to be useful as solvents for this process. Polymerization can take place on the carbon fiber electrode, with initial wetting of the fiber surface leading to better adhesion of the polymer formed. The structure and properties of the polymer can be varied by employing different vinyl and cyclic monomers in homopolymerization. Chemical bond can also be formed, such as polymer grafting to the carbon fiber surface. 

Reynolds WN. Structure and physical properties of carbon fibers. In Walker Jr. PL, Thrower PA,. Chemistry and Physics of Carbon, vol. 11, New York Dekker. 1973 pp. 1-67. 

Koyama T, Endo M. Structure and properties of graphitized carbon fiber. Jpn J Appl Phys 1974 13 1933-1939. 

In this chapter we provide a description of the processing, structure, and properties of high temperature ceramic fibers, excluding glass and carbon, which are dealt with in separate chapters because of their greater commercial importance. Before we do that, however, we review briefly some fundamental characteristics of ceramics (crystalline and noncrystalline). Once again, readers already familiar with this basic information may choose to go directly to Section 6.5. 

Structure and Physical Properties of Carbon Fibers, W. N. Reynold,s Highly Oriented Pyrolytic Graphite, A. W. Moore Deformation Mechanisms in Carbons, Gwyn M. Jenkins Evaporated Carbon Films, I. S. McLintock and J. C. Orr... 

Dick J.S. 2001. Rubber Technology Compounding and Testing for Performance. Hanser Gardner. Donnet J.B. and A. Vidal. 1986. Carbon Black. Advances in Polymer Science. Springer. Donnet, J.B., T.K. Wang, and J.C.M. Peng. 1998. Carbon Fibers. 3rd ed. Marcel Dekker. Erman B. and J.E. Mark. 1997. Structures and Properties of Rubber-Like Networks. Oxford University Press. 

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