Non‐isothermal crystallization of poly(etheretherketone) aromatic polymer composite

Non‐isothermal crystallization kinetics of poly(ether‐etherketone), PEEK, in the presence of carbon fibers has been studied for APC‐2 composites. Samples of APC‐2 PEEK composite were cooled from the melt at rates ranging from −1 to −20°C/min. A differential scanning calorimeter was used to monitor heat flow during the non‐isothermal crystallization. Effects of cooling rate on crystallization temperature, degree of crystallinity, and conversion rate were studied. We show that the Ozawa analysis fails to provide an adequate description of the non‐isothermal crystallization process in composite PEEK. A modified Avrami analysis was used to describe crystallization kinetics. For the composite material, the change from the primary kinetics of free crystal growth to slower secondary kinetics occurred at about 50 percent relative conversion for all cooling rates. Non‐isothermal crystallization in APC‐2 composite PEEK can be characterized by higher initiation temperature, higher heat flow maximum temperature, and greater relative conversion by primary processes when compared to 450G neat resin PEEK crystallization.