Carbon Fiber Prepregs

In practice, epoxy-amine reactions in carbon fiber prepregs, and epoxyphenol reactions in molding compounds, are often accelerated by the addition of a Lewis acid (typically a BF3 - amine complex) or a Lewis base (often a tertiary amine), as catalysts. ... 

Unidirectional carbon fiber prepreg manufactured by Sunkyung Industry Co., Suwon, Korea. 

However, the cure behavior of the cyanate systems has been reported to be different in prepregs, the difference attributed to the presence of fibers. The behavior was studied using dynamic DSC [142], solid state 13C-NMR, SEM, and FTIR [99] for a 13C-labeled BACY/carbon fiber prepreg. At high cure temperatures, the observed Tg decreased for the prepreg. 

Global Energy Concepts of Dayton, OH, USA is using carbon fiber prepreg for large wind blades for the Vestas 90 m long blade. This... 

Cycom 3100 A proprietary BMI formulation for carbon fiber prepreg... 

Figure 34 presents the example of a modem civilian jumbo aircraft, the Airbus A380, in which a wide variety of stracturally relevant components and composites are used [76]. Figure 35 illustrates impressively how metals and fiber composites have competed, leading to mumal improvements [76]. These developments were made possible to a great extent by price reductions for the carbon fiber prepregs, which are down 50 % since 1990. 

Courtaulds developed many products [153] based on carbon fibers prepreg as warp sheet and tape, random fiber mats, preferred orientation mats, chopped fiber, thermoset and thermoplastic molding compounds and polytetrafluroethylene (PTFE) impregnated tow. Oxidized PAN fiber was available as continuous tow, tops, yarns, woven and knitted fabrics. 

Table 21.7 lists companies who manufacture carbon fiber prepreg equipment. Prepreg manufacturers do make their own in-house equipment (Figure 21.68) and a typical layout of a prepreg machine is shown in Figure 21.69. 

Figure 22.7 Expanded core technique showing detail of carbon fiber prepreg inserts. Source Reprinted with permission from George J, Technology puts carbon fibre into mass markets. Eureka, Franks-Hall, 35-37, Mar 1985. Copyright 1985, Franks Hall.

Two submarines capable of diving to a depth of 6000 m were constructed using a sandwich construction of a special syntactic core and carbon fiber prepreg, to withstand the extreme pressures and were used to enable underwater shots when making the film Titanic. 

Thrust SSC (Super Sonic Car), in 1998, became the first land vehicle to break the sound barrier, achieving 764 mph across the Black Rock desert in Nevada (Figures 23.38, 23.39). Cytec s carbon fiber prepreg was used around the forward position of Thrust s engine nacelles, nose cone, air inlet structures and cockpit canopies. 

A carbon fiber bicycle wheel rim is fabricated by Sun Rims saving 400 g over an A1 rim and with 30% less carbon than that achieved by competitors using carbon fiber braid. A core of foam is rolled into a circle to fit the mold rim periphery and a braid sleeve drawn over the core with the ends overlapped. Extra pieces of carbon fiber prepreg are positioned at high stress points, the reinforcement is impregnated with epoxy resin and the lay-up is then compression molded. The pressures are sufficient for the overlap joint to be uniformly incorporated into the rim thickness. 

Bryte Technologies Inc., San Jose, California, USA—manufacturer of carbon fiber prepreg and now a member of Royal Ten Cate. 

ICI Fiberite, Winona, Maine, USA—in 1985, ICI America purchased the Fiberite subsidiary of Beatrice Foods Co. Ltd, which has subsequently been acquired by Carlyle Enterprises. Fiberite is a leading US producer of carbon fiber prepregs. 

Narmco, USA a well known prepreg producer in the USA that was taken over by BASF, then Amoco and now owned by Cytec, which used to be the prepreg arm of Cyanamid. Newport Adhesives Composites Inc., Irvine, Califomia, USA associated with Grafil Inc. and manufacture a range of carbon fiber prepreg and also factor parent company Mitsubishi Rayon Corporation s Pyrofil prepreg. 

Sumika-Hercules, Saidai, Japan—a joint venture of the Sumitomo Chemical Co., Japan with Hercules Inc., USA, to produce PAN precursor and sell carbon fiber prepreg. Now part of the Hercules-Hexcel group. 

In 1968, Morgan joined a team at Courtaulds to manufacture carbon fibers and subsequently set up and managed a control laboratory to monitor production. He later became involved with production aspects relating to carbon fiber prepreg and pultrusion. Morgan took on the additional role of chief quality inspector in 1976 and gained approval for the production processes to Defence Standard 05-24, the forerunner of BS 5750. In 1980, he was appointed to Courtauld s Carbon Fibres division board as director with technical responsibilities. 

Delano (10) studied the use of cyanate esters in carbon fiber prepregs for advanced structural composites. He found that state of the art mechanical properties versus epoxies could be obtained in composites even though the cyanate were not fully crosslinked. Using new catalyst technology (unpublished) we have determined that fully crosslinked systems can be obtained at 170-200 C. These materials have improved thermal, mechanical, electrical, toughness and moisture resistance properties over epoxy resins. 

TABLE III. Typical cure sequence for poly[2,2 -(m-phenylene)-5,5 -b1 benzimidazole] prepolymer in a carbon fiber prepreg [13]. 

Schneider, K. and Lang, R.W. (1990) Second source qualification of carbon fiber prepregs for primary and secondary airbus structures, in Proc. 11th International European Chapter Conference of SAMPE SAMPE. 

Mitsubishi Chemical Co, 1999. Carbon Fiber Prepreg Sheet (Replark ). Available from http // www.m-kagaku.co.jp/engjish/aboutmcc/division/prod/carbonfiber/r-products.htm. 

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