Isothermal and nonisothermal crystallization kinetics of nylon 6/functionalized multi-walled carbon nanotube composites

The well dispersion of functionalized multi-walled carbon nanotube (f-MWCNT) in nylon 6 matrix was prepared by solution mixing techniques. The isothermal and nonisothermal crystallization kinetics of nylon 6 and nylon 6/f-MWCNT nanocomposites were studied by differential scanning calorimetry (DSC), X-ray diffraction and polarized optical microscopy analysis. DSC isothermal results revealed that the activation energy of nylon 6 extensively decreased by adding 1 wt % f-MWCNT into nylon 6, suggesting that the addition of small amount of f-MWCNT probably induces the heterogeneous nucleation. Nevertheless, the addition of more f-MWCNT into nylon 6 matrix reduced the transportation ability of polymer chains during crystallization process and thus increased the activation energy. The nonisothermal crystallization of nylon 6/f-MWCNT nanocomposites was also discussed. (C) 2007 Wiley Periodicals, Inc.