Carbon fibers composition

Composites. Various composite materials have evolved over the years as a significant class of high performance textile products. The prototype composite is carbon fiber with an epoxy resin matrix for stmctural akcraft components and other aerospace and military appHcations. Carbon fiber composites ate also used in various leisure and spotting items such as golf clubs, tennis rackets, and lightweight bicycle frames. However, other types of appHcations and composites ate also entering the marketplace. For example, short ceUulose fiber/mbbet composites ate used for hoses, belting, and pneumatic tire components. 

Carbon-Fiber Composites. Cured laminates of phenoHc resins and carbon-fiber reinforcement provide superior flammabiHty resistance and thermal resistance compared to unsaturated polyester and epoxy. Table 15 shows the dependence of flexural strength and modulus on phenoHc—carbon-fiber composites at 30—40% phenoHc resin (91). These composites also exhibit long-term elevated temperature stabiHty up to 230°C. 

Table 15. Strength Properties of Phenolic—Carbon-Fiber Composites...

Carbon—Carbon Composites. Above 300°C, even such polymers as phenoHcs and polyimides are not stable as binders for carbon-fiber composites. Carbon—carbon composites are used at elevated temperatures and are prepared by impregnating the fibers with pitch or synthetic resin, foUowed by carbonization, further impregnation, and pyrolysis (91). 

Table 2. Effect of Peak Carbonization Temperature on PAN Carbon Fiber Composition, wt %...

PMR-15—carbon fiber composites include jet-engine cowlings, ducts, compressor blades, and flaps and fairings (24,38). 

Fig. 7. Micrographic cross section of an autoclaved carbon fiber composite.

Chung, D. D. L., Carbon Fiber Composites, Butterworth-Heinemann, Boston, 1994. 

A recently developed adsorbent version of ORNL s porous carbon fiber-carbon binder eomposite is named carbon fiber composite molecular sieve (CFCMS). The CFCMS monoliths were the product of a collaborative researeh program between ORNL and the University of Kentueky, Center for Applied Energy Researeh (UKCAER) [19-21]. The m.onoliths are manufactured in the manner deseribed in Section 2 from P200 isotropic pitch derived fibers. While development of these materials is in its early stages, a number of potential applieations can be identified. 

Jagtoyen, M. and Derbyshire, F., Carbon fiber composite molecular sieves for gas separation. In Proc. Tenth Annual Con/, on Fossil Energy Materials, CONF-9605167, ORNL/FMP-96/I. Oak Ridge National Laboratory, 1996, pp. 291 300. 

Burchell, T. D., Carbon fiber composite molecular sieves. In Proc. Eighth Annual Conference on Fossil Energy Materials, ORNL/FMP-94/1, CONF-9405143, Oak Ridge National Lab, U.S.A., 1994, pp 63 70. 

Burchell, T.D., Weaver, C E., Derbyshire, F., Fei, Y.Q. and Jagtoyen M., Carbon fiber composite molecular sievesisynthesis and characterization. In Proc. Carbon 94, Granada, Spain, Spanish Carbon Group, 1994, pp. 650 651. 

Burchell, T.D. and Judkins, R.R. Passive CO2 removal using a carbon fiber composite molecular sieve. Energy Convers. Mgmt, 1996, 37(6-8), 947 954... 

Effects of neutron displacements on graphite and carbon fiber composites... 

D.L. Chung, Carbon Fiber Composites, Pub. Butterworth-Heinemann, Newton, MA. 1994. 

Wcll-hccled bicyclists opt for titanium or carbon-fiber composites. 

Most carbon fiber composites are based mainly on thermosetting epoxy matrices. 

FIGURE 12.18 Stress-strain curves of rubber-fiber composites developed for solid rocket motor insulator A, ethylene-propylene-diene monomer (EPDM) rubber-carbon fiber composites B, EPDM mbber-melamine fiber composites C, EPDM mbber-aramid fiber composites and D, EPDM rubber-aramid pulp composites. 1 and 2 stands for unaged and aged composites respectively. Carbon fiber- and melamine fiber-reinforced composites contain resorcinol, hexamine, and silica in the concentrations 10, 6 and 15, respectively and aramid fiber- and aramid pulp-based composites contain resorcinol, hexamine, and silica in the concentrations 5, 3 and 15, respectively. (From Rajeev, R.S., Bhowmick, A.K., De, S.K., and John, B., Internal communication. Rubber Technology Center, Indian Institute of Technology, Kharagpur, India, 2002.)... 

A part, consisting of a carbon fiber composite tube, was initially adhered to the inside of a short titanium coupling by a silica-filled epoxy. The bond failed and a fluorinated mold release was believed to be the cause of the failure and was the purpose for this investigation. A sample of the epoxy (Sample A) and the part (Sample B) were submitted for X-ray photoelectron spectroscopy (XPS) to analyze for the presence of both fluorine and silicon. 

An FRP pipeline typically consists of (1) an inner nonpermeable barrier tube that transports the pressurized gas, (2) a protective layer over the barrier tube, (3) an interface layer over the protective layer, (4) multiple glass or carbon-fiber composite layers, (5) an outer pressure barrier layer, and (6) an outer protective layer. Each of the layers provides a distinct function and the interaction between the layers produces a pipe with exceptional performance. 

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. 

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