Title: Thermal Degradation of Poly (Ether Ketone Ketone) Copolymers at Processing Temperatures
Authors: Chris D. Croshaw, Jeffrey S. Wiggins
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.
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Conference: SAMPE NEXUS 2021
Publication Date: 2021/06/29
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