Nothing contained herein constitutes a license to practice under any patent and it should not be construed as an inducement to infringe any patent, and the user is advised to take appropriate steps to be sure that any proposed action will not result in patent infringement. ![]() The user should thoroughly test any application before commercialization. Since the conditions and methods of use of the information referred to herein are beyond our control, Arkema expressly disclaims any and all liability as to any results obtained or arising from any reliance on such information NO WARRANTY OF FITNESS FOR ANY PARTICULAR PURPOSE, WARRANTY OF MERCHANTABILITY, OR ANY OTHER WARRANTY, EXPRESS OR IMPLIED, IS MADE CONCERNING THE INFORMATION PROVIDED HEREIN. The statements, technical information and recommendations contained herein are believed to be accurate as of the date hereof. For more information, contact Robert Barsotti at Arkema Inc at 900 First Avenue, King of Prussia, PA 19406-1308 USA phone (484)-745-9142, or All the data provided in the article is based on studies by Arkema. is the global research and development manager for Kepstan ® PEKK at Arkema Inc, while Jonathon Hollahan is a business development engineer for Arkema Inc, focused on Kepstan. Figure 8 shows both amorphous and thermoformed PEKK parts, illustrating the achievable draw ratios and intricate features. ![]() This thermoforming technology can be extremely valuable in aerospace interior or semiconductor applications where the chemical resistance of PEKK gives it a strong advantage over other amorphous high performance polymers commonly used for thermoformed parts. PEKK’s ability to be easily colored adds additional value in these applications. The resulting thermoformed parts have all the excellent thermal, mechanical, chemical resistance and FST properties of semi-crystalline PEKK. Mold temperatures of 446☏/230-482☏/250☌ allow for rapid crystallization. Sheets are then heated to temperatures above their glass transition temperature for easy forming into complex shapes, with demonstrated draw ratios of up to at least 3. Amorphous PEKK sheets can be extruded with thickness of 0.012″ to 0.118″ (0.3 – 3 mm). This technology brings huge benefits for large area plastic components common in bus, light rail, or rail applications. PEKK’s tunable crystallinity allows for thermoforming of sheets. This same insulative performance makes PEKK an excellent candidate for stock shape applications in the electronics and semiconductors markets, including RFI/EMI connectors, wafer/electronic carriers or trays and semiconductor test sockets. Both machined components and insulation for magnet wire can benefit from the low dielectric constant of PEKK (as low as 2.6) and its ability to outperform other PAEKs by better maintaining this lower dielectric constant at the elevated temperatures reached during operation. Increased partial discharge induction voltages (PDIV) are required to prevent cross-talk amongst electrical components. Materials with low dielectric constants are becoming increasingly attractive as electric vehicles go to higher power and voltages. PEKK’s ability to be melt processed can bring tremendous value when compared to the long cycle times and capital investment needed to process PAI. Formulated PEKK grades have shown performance on par with that of wear and friction PAI formulations (often considered the gold standard), as evaluated using thrust washer testing (ASTM D-3702). PEKK can be formulated for specific applications with wear and friction requirements. ![]() Figure 2 shows a variety of extruded PEKK stock shapes and parts machined from PEKK stock shapes.Ĭarbon or glass filled reinforced PEKK grades are available for increased modulus and strength. PEKK is available in flake, pellets or powders with varying melt viscosities and copolymer ratios to suit the needs of any process. Through PEKK grade selection and adjustment of process parameters, either amorphous or semi-crystalline PEKK can be achieved, depending on the needed performance characteristics of the end use product. The tunable crystallization speed of PEKK allows it to be easily processed with both traditional extrusion and injection molding processing or via more novel processes such as additive manufacturing (both filament based and laser sintering), powder coating, rotomolding, thermoforming or automated tape placement (for composite fabrication). PEKK copolymers span a range of behaviors from pseudo-amorphous (super slow to crystalize) to semi-crystalline. By changing this T:I ratio, it is possible to change the way chains pack together, resulting in a range of crystallization speeds and melting points. An additional advantage is that PEKK can be a copolymer, composed of straight ( Terepthalic) and kinked ( Isophtalic) units.
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