Third patent issued for flexible thermoplastic prepreg
The third patent for a flexible thermoplastic prepreg, US 10,626,235, has been awarded to Robert Davies. It provides for random resin bridges between the outer surfaces of each tow, enabling a stabilized, wider tape to be produced from a single tow.
The first patent, issued in 1998, used a powder process and was produced by Applied Fiber Systems (Clearwater, Fla., U.S.), a company that was acquired in March 2020 by Hexcel (Stamford, Conn., U.S.). The second patent, US 7,790, 284, was issued in 2010 and previously licensed to Fibrtec Inc. (Atlanta, Texas, U.S.), which marketed the technology under the brand name FIBRFLEX. Both the 2010 and 2020 patents leverage low-cost direct melt extrusion onto individual tow bundles to create a semi-preg by coating only the outside fibers. The inner filaments remain uncoated, which allows the outer surfaces to shear against each other providing flexibility without breaking. Both the 2010 and 2020 patents, as well as manufacturing technology and equipment designs are now offered by Precept One LLC (Texarkana, Texas, U.S.).
This technology has been successfully demonstrated with 24K and 50K carbon fiber tows, enabling lower fiber areal weights while maintaining flexibility for downstream processes like weaving and braiding. Such FIBRFLEX towpreg also provides even resin distribution around the filament bundle and requires only a radial displacement of only 0.05-0.08 millimeters — easily accomplished with the addition of pressure when the resin is in a melt condition — to produce a void-free laminate.
FIBRFLEX flexible prepreg revolutionizes handling and forming compared to rigid organosheets and can be produced using a wide range of thermoplastic resins such as PP, PA6, PA66, PPS, PAI and PEEK. The scalable FIBRFLEX manufacturing process is compatible with many fibers such as E-glass, carbon and aramid in all available tow sizes, making it suitable for complex structures not previously considered.
About Precept One LLC
Precept One LLC is offering its unique FIBRFLEX intellectual property (IP) for advanced molding materials of exceptionally high strength, low weight, continuous fiber thermoplastic composites, to displace metals and other composites. For more information, contact Bob Davies: bob@PreceptOne.com
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