Unveiling PEEK’s crystallization kinetics with the hay model: an isothermal DSC study

Abstract

This research demonstrates the applicability of the Hay Model, a modified version of the Avrami Model, to analyze the isothermal crystallization kinetics of poly(ether-ether-ketone) (PEEK), a high-performance thermoplastic polymer. While the Hay Model has proven effective for a variety of polymers, its application to PEEK remains unexplored. This research addresses this gap by using isothermal melt crystallization data obtained at temperatures between PEEK's melting and glass transition temperatures, measured through Differential Scanning Calorimetry (DSC). The obtained data is analyzed using both Avrami and Hay Models. The results suggest that the Hay Model is more effective in interpreting isothermal crystallization kinetics of PEEK, as validated with the Kolmogorov-Smirnov test. Then, the Lauritzen-Hoffman theory was also employed alongside the Hay Model to determine temperature-dependent crystallization rates. This study enhances the modeling of polymer processing techniques with PEEK and solidifies the Hay Model as a more effective kinetic model in describing the isothermal crystallization kinetics of PEEK.