| Since KynolTM novoloid fibers are infusible and have an inherently high carbon content of about 76wt%, they are excellent precursors for carbon fiber and textile materials. Either unprocessed tow or finished materials such as felt and woven fabric may be carbonized with high yield by simple one-stage high-temperature processing in an inert atmosphere, without the need for any pre-treatment or application of tension during carbonization. Shrinkage of the material during carbonization is predictable and low (around 20%), and structural distortion is minimal.
KynolTM novoloid-based carbon fibers are amorphous in structure, and even treatment at the usual graphitization temperatures of 2000 C or higher does not result in the formation of the typical well-ordered graphite molecular structure. Therefore KynolTM carbon fiber is a low-modulus, moderate-strength material in comparison with the high-modulus, high-strength carbon and graphite fibers made from polyacrylonitrile (PAN) and other precursors. KynolTM carbon products are available in regular (95% carbon) and high-purity (99.8% carbon) grades. The table gives the typical properties of KynolTM carbon fibers compared to pitch- (low modulus) and PAN- (high modulus) based carbon fibers. KynolTM carbon fiber is soft and pliable, produces little dust or fly on processing, and has good lubricity and a lower specific gravity than other types of carbon fiber. |
It retains much of the good dispersability and affinity for matrix materials of the novoloid precursor. Its heat, chemical, and electrical characteristics are comparable to those of other carbon fibers. It is thus highly suitable for production of braided packings, either impregnated or unimpregnated (no coating is required for braiding even of the high-purity filament yarn); bearings and other low-friction materials; carbon-fiber-containing elastomers with uniform, predictable, and high electrical conductivity; and highly heat- and chemical-resistant gaskets. Paper made from KynolTM chopped carbon fiber is suitable for resin impregnation to produce sheet electrodes for electrostatic precipitators. KynolTM carbon yarns, felts, and fabrics are used in protective curtains, vacuum furnace insulation, and static-elimination brushes for office equipment.
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