Carbon filament reinforced plastics

A carbon fiber-reinforced plastic (CFRP) preform is made using two-dimensional (2-D) fiber fabrics (cut fibers and filament-wound or braided preforms or high- carbon-yield precursors). 

In reinforced plastics various inorganic materials are dispersed in the polymer. Carbon black reinforced elastomers have already been considered see Section 9.16.2. For fiber composites, two subtypes are important, the short fiber-containing materials, which are thermoplastic, and the continuous filament types, which cannot flow. While short fibers can be melt blended with thermoplastics, they are often embedded in monomeric mixes, followed by polymerization in situ. Continuous fibers are always processed via monomeric mixes which can flow over the beds of fibers. Of course, these monomeric mixes may have polymers or prepolymers dissolved in them, raising the viscosity, and reducing shrinkage on polymerization. An example of the continuous filament type is a tape composite, familiar as the strapping tape used for packaging. 

Tests on plastics in deep water have been extremely encouraging. Low-carbon steel corroded at a rate one-third greater than in surface waters. Filament-wound reinforced plastic cylinders and PVC buoys retained their strength. PVC washers and the silicone sealing compound used in steel-to-aluminum joints helped prevent corrosion. 

For various applications, carbon fiber staple yarns are processed into woven and noncrimp fabrics, which are used for building components and as prepregs. Textile structures of carbon filaments are used in composite plastics and with fiber-reinforced concrete. Furthermore, short fibers down to 6 mm in length are used. 

Other uses for continuous-filament industrial yams include reinforcement cords for plastics, as a precursor for carbon and ceramic filaments, and for tents, awnings, strappings, etc. 

Count Louis Marie Hilaire Chardonnet, an assistant to Louis Pasteur, patented the process of producing filaments by forcing Collodion through small holes (spinnerets) in 1884. This "Chardonnet sifi" was a sensation at the Paris Exposition in 1891. Because of its inherent flammabiHty, this fiber was called "mother-in-law silk". Nevertheless, Chardonnet received the Perkin Medal in 1914 for this development. The carbon fibers used by Swan Edison in the nineteenth century were also used a century later as reinforcements for sophisticated plastic composites. 

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