Title: Thermal Degradation of Poly (Ether Ketone Ketone) Copolymers at Processing Temperatures

Authors: Chris D. Croshaw, Jeffrey S. Wiggins

DOI: 10.33599/nasampe/s.21.0450

Abstract: Poly (ether ketone ketone) (PEKK) copolymers utilize different proportions of para and meta ketone linkages in the polymer backbone to alter the crystallization and melting temperatures. PEKK composed entirely of para linkages has a melting temperature that coincides with thermal degradation at 400°C, a common processing temperature. Literature has shown that the addition of meta linkages into the PEKK backbone reduces the melting temperature, thus avoiding thermal degradation. However, the influence of meta linkages in the PEKK backbone on thermal degradation has not been investigated. Herein, three PEKK copolymers with para to meta ratios of 80/20, 70/30, and 60/40 are characterized to determine the influence of backbone linkages on thermal degradation. Thermogravimetric analysis has been used to measure the char yields for each of the PEKK copolymers. Shear rheology measured changes in viscosity during isothermal temperature holds that occur due to thermal degradation at processing temperatures. The influence of thermal degradation on isothermal crystallization kinetics in aerobic and anaerobic environments was quantified using differential scanning calorimetry. This research demonstrates that increasing the proportion of meta ketone linkages in the PEKK backbone increases thermal degradation at processing temperatures.

References: 1. I. Chang, PEKK as a new thermoplastic matrix for high performance composites. United States: SAMPE, 1988. 2. K. Gardner, B. Hsiao, R. Matheson and B. Wood, Structure, Crystallization and Morphology of Poly (Aryl Ether Ketone Ketone). Polymer (Guildf). 1992. https://doi.org/10.1016/0032-3861(92)91128-O 3. B. S. Hsiao, K. H. Gardner, and S. Z. D. Cheng, Crystallization of poly(aryl ether ketone ketone) copolymers containing terephthalate/isophthalate moieties. J. Polym. Sci. Part B Polym. Phys., 1994. https://doi.org/10.1002/polb.1994.090321604. 4. T. Choupin, B. Fayolle, G. Régnier, C. Paris, J. Cinquin, and B. Brulé, Macromolecular modifications of poly(etherketoneketone) (PEKK) copolymer at the melting state. Polym. Degrad. Stab., 2018. https://doi.org/10.1016/j.polymdegradstab.2018.07.005. 5. K. Frank, J, Wiggins, Effect of Stoichiometry and Cure Prescription on Fluid Ingress in Epoxy Networks. J. Appl. Polym. Sci. 2013. https://doi.org/10.1002/app.39140. 6. J. Misasi, Hybrid Aryl-Ether-Ketone and Hyperbranched Epoxy Networks. University of Southern Mississippi, 2015. 7. R. Varley, B. Dao, S. Tucker, S. Christensen, J. Wiggins, Effect of Aromatic Substitution on the Kinetics and Properties of Epoxy Cured Tri-Phenylether Amines. J. Appl. Polym. Sci. 2019. https://doi.org/10.1002/app.47383. 8. E, Courvoisier. Y. Bicaba, X, Colin, Multi-Scale and Multi-Technique Analysis of the Thermal Degradation of Poly(Ether Ether Ketone). Polym. Degrad. Stab. 2018. https://doi.org/10.1016/j.polymdegradstab.2018.03.001. 9. M. Day, T. Suprunchuk, J. Cooney, D. Wiles, Thermal Degradation of Poly( Aryl-Ether-Ether-Ketone) (PEEK): A Differential Scanning Calorimetry Study. J. Appl. Polym. Sci. 1988.

Conference: SAMPE NEXUS 2021

Publication Date: 2021/06/29

SKU: TP21-0000000450

Pages: 9

Price: FREE