Polyacrylonitrile based carbon fibers

Morita, K., Murata, A., Ishitani, A., et al. (1986). Characterization of commercially available PAN (polyacrylonitrile)-based carbon fibers. Pure Appl. Chem., 58, 456-68. 

Jagannathan, S. et al.. Structure and electrochemical properties of activated polyacrylonitrile based carbon fibers containing carbon nanotubes. J. Power Sources. 2008, iS5(2 , 676-684. 

Ogawa H, Studies on the improvement of productivity of high-performance polyacrylonitrile-based carbon-fibers. 1. Effects of comonomer methyl acrylate composition on production of polyacrylonitrile-copolymer-based carbon-fibers, Nippon Kogaku Kaishi, No.5, 464--470, 1994. 

Figure 5.33 Longitudinal section of PAN based HM carbon fiber obtained by TEM. Source Reprinted from Morita K, Murata Y, Ishitani A, Murayama K, Nakajima A, Characterization of commercially available PAN polyacrylonitrile)-based carbon fibers. Pure Appi Chem, 58(3), 455-468, 1986.

Ogawa H, Effects of comonomer and 2-step oxidation on production of polyacrylonitrile-based carbon-fibers, Nippon Kagaku Kaishi, 6, 560-564, 1994. 

Xu B, Wang X S and Lu Y (2006) Surface modification of polyacrylonitrile-based carbon fiber and its interaction with imide, Appl Surf Sci 253 2695-2701. 

Chakrabarti, K., P. M. G. Nambissan, C. D. Mukherjee, K. K. Bardhan, C. Kim, and K. S. Yang (2006). Positron annihilation spectroscopy of polyacrylonitrile-based carbon fibers embedded with multi-wall carbon nanotubes. Carbon 44(5) 948-953. 

Polyacrylonitrile-based carbon fiber (liquid crystal) TORAYCA (Toray) Besfight (Toho Tenax) Pyrofil (Mitsubishi Rayon) 17.6-39.6 1232-3080... 

Cliae, H.G., et al. Carbon nanotube reinforced small diameter polyacrylonitrile based carbon fiber.Com/705.5cz. Technol.20Q9, 69(3), 406 13. 

Various surface pretreatments, often referred to as primers, are put on fibers and other textiles by the manufacturers to enhance subsequent bonding. Depending on the subsequent use of the textiles, the change in adhesion can be negative, nonexistent, or positive. In interlaminar shear strength tests of untreated and oxidative surface-treated polyacrylonitrile-based carbon fiber/epoxy composites the shear stress went from 14.9 to 22.1 MPa. 

Polymers mesophase pitch polyacrylonitrile carbons" mesocarbon microbeads, carbon fibers PAN-based carbon fibers ... 

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. 

PAN-based carbon fiber processing flow chart, 26 731. See also Polyacrylonitrile (PAN)... 

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. 

Recall from Section 1.4.5.1 that there are two primary types of carbon fibers polyacrylonitrile (PAN)-based and pitch-based. There are also different structural forms of these fibers, such as amorphous carbon and crystalline (graphite) fibers. Typically, PAN-based carbon fibers are 93-95% carbon, whereas graphite fibers are usually 99+%, although the terms carbon and graphite are often used interchangeably. We will not try to burden ourselves with too many distinctions here, since the point is to simply introduce the relative benefits of continuous-fiber composites over other types of composites, and not to investigate the minute differences between the various types of carbon-fiber-based composites. The interested reader is referred to the abundance of literature on carbon-fiber-reinforced composites to discern these differences. 

The purpose of the current work is the development of the effective electron-optical system for the cathodoluminescent light source with the field emission cathode based on polyacrylonitrile (PAN) carbon fibers [1]. 

Polyacrylonitrile (PAN) precursor fibers are more expensive than rayon. Nevertheless, PAN is more commonly used because the carbon fiber yield is about double that from rayon. Pitch-based carbon fibers are also important, because, potentially pitch is perhaps the cheapest raw material. Table 8.2 shows that carbon yield is highest from the mesophase pitch. The reader is cautioned that this is true only if we exclude the losses during the mesophase conversion step. If, however, one compares the overall carbon fiber yield from raw pitch to that from PAN, then the yield from PAN is higher. In any event, the carbon fiber yield or precursor weight loss is a very important factor in the economics of processing. 

Polyacrylonitrile (PAN) is the most common precursor used to make carbon fibers. A flow diagram showing the steps involved in making PAN-based carbon fiber is shown in Fig. 8.3. The PAN precursor has a flexible polymer chain structure like any other polymer, but it has an all carbon backbone chain that contains polar nitrile groups, as shown in Fig. 8.4. During the stabilization treatment, the PAN precursor fiber is heated to 200-220 C, under tension. When this is done oxygen is absorbed, and it serves to cross-link the chains the fibers turn black, and a stable ladder structure is formed. A ladder polymer is a rigid... 

Materials. Several precursor materials exist for the production of carbon fibers (2). However, most of the presently available carbon fibers are synthesized from polyacrylonitrile (PAN) since these fibers have the best mechanical properties. Five PAN based carbon fibers were used in this study ... 

In carbon fiber felts, however, only one kind of pores, interparticle pores, are observed among the fibers (Fig. 27.4). The surface of each fiber is smooth and no pores are inside of the fibers. Felts composed of polyacrylonitrile (PAN)-based and isotropic pitch-based carbon fibers were used as sorbents in the present work. 

Yusof, N. and Ismail, A. Rost spiiming and pyrolysis processes of polyacrylonitrile (RAN)-based carbon fiber and activated carbon fiber A review. J. Anal. Appl. Pyrolysis 20X2, 93, 1-13. 

Carbon fibers can be prepared from polymeric precursor materials such as polyacrylonitrile (PAN), cellulose, pitch and polyvinylchloride, which are discussed in detail later. PAN-based carbon fibers predominate and have good strength and modulus properties, whereas carbon fiber can be made with a higher modulus, albeit a lower strength, using a pitch-based precursor. 

Figure 12.32 XPS survey spectra of PAN carbon fiber precursors oxidized to (a) 35, (b) 40, (c) 45 and (d) 50 min and finished carbon fiber with an epoxy size. Source Reprinted with permission from Bhardwaj A, Bhardwaj IS, ESCA characterization of polyacrylonitrile based carbon fibre precursors during its stabilization process, J AppI Polym Sci, 51(12), 2015-2020,1994. Copyright 1994, John Wiley Sons Ltd.

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