Non-isothermal crystallization kinetics of poly(phthalazinone ether sulfone)/MC nylon 6 in-situ composites

Non-isothermal crystallization behaviors and non-isothermal crystallization kinetics of poly(phthalazinone ether sulfone) (PPES)/MC nylon 6 in-situ composites prepared by anionic ring-opening polymerization were explored by differential scanning calorimetry (DSC) at various cooling rates. The Fourier transform infrared spectroscopy (FTIR) results confirmed that PPES/MC nylon 6 in-situ composites were successfully synthesized. The scanning electron microscopy (SEM) results demonstrated that PPES particles were well dispersed, at micron levels, in the MC nylon 6 matrix. The DSC results showed that inclusion of PPES to MC nylon 6 increased the crystallinity, while the crystallization rate was reduced. Crystallization kinetic analysis by Jeziorny model exhibited two levels of primary and secondary crystallization mechanisms for all samples, and the lower values of Z(c) for the in-situ composites as compared to those of MC nylon 6 indicated that MC nylon 6 crystallization process becomes slower in the presence of PPES. The F(T) values of the composites were generally higher as compared to those of pure MC nylon 6, indicating that the interaction between PPES and MC nylon 6 matrix was stronger and the movement of the polymer molecular chain was difficult. Moreover, activation energies of crystallization of the in-situ composites were lower than that of MC nylon 6. Analysis of data founded on theoretical models revealed that PPES acts as a nucleating agent in the nucleation stage and restricts the movement of chain segments for MC nylon 6 during crystal growth.

Automated summary

The non-isothermal crystallization behaviors and kinetics of poly(phthalazinone ether sulfone) (PPES)/MC nylon 6 composites were studied using differential scanning calorimetry (DSC). The inclusion of PPES increased the crystallinity of MC nylon 6, but the crystallization rate decreased. PPES acted as a nucleating agent and restricted the movement of chain segments during crystal growth.