Vapor-Grown Carbon Fibers (VGCF) are now being produced in moderate volume by several companies around the world, making larger quantities of these materials available for experiment and manufacturing. These fibers have been used to fabricate thermoset and thermoplastic composites with improved tensile strength, tensile modulus, and electrical conductivity. Even so, barriers to more general application of these fibers will have to be surmounted. VGCFs are, difficult to permeate with resins, and to a certain extent, fragile. Moreover, the fibers as produced have a low density, making them difficult to handle and compound. Nagging worries continue that the fibers will present a lung hazard if they are dispersed in air. Present composites have shown properties far below optimum, because they are made of nearly randomly oriented fibers. To achieve really optimal properties, composites with reasonable well oriented fibers must be fabricated.
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