Non-isothermal crystallization kinetics of poly(ether sulfone) functionalized graphene reinforced poly(ether ether ketone) composites

The impact of poly (ether sulfone) modified graphene (f-GE(i)) on the non-isothermal crystallization kinetic behavior of PEEK composites was investigated by differential scanning calorimetry at various cooling rates. According to the results, the addition of f-GE(i) reduced the crystallinity of the PEEK composites and shortened the total crystallization time. The peak temperature and nucleation activity of the f-GE(i) increased with increasing the mass ratio of PES to GE before declining, those of PEEK/f-GE(5) composites were the highest, which suggested the potential of f-GE(5) to provide more nucleation sites for PEEK matrix. The addition of f-GE(i) decreased the temperature gradient required during the crystallization process and reduced the crystallization activation energy. The log(F(T)) values of PEEK/f-GE(5) were significantly higher compared to the other PEEK/f-GE(i) composites, indicating that the interaction between f-GE(5) and PEEK matrix was stronger and the mobility of the polymer molecular chain was much difficult.