The nonisothermal crystallization behavior of Copper/low-density polyethylene (LDPE) nanocomposites was investigated by differential scanning calorimetry (DSC). The nanocomposites were prepared by solution blending method, and the traditional extrusion melt method was also employed for comparison. The DSC results show that under identical copper content condition, the crystallization of the LDPE is facilitated owing to the higher degree of molecular regularity and the lesser chain entanglement for the nanocomposites prepared by the solution blending method in comparison with the traditional extrusion melt method. The differences of nonisothermal crystallization behavior diminish with the increasement of copper content between the nanocomposites prepared by the two methods. SEM/EDX was applied to study the dispersion of copper nanoparticles in the nanocomposites, and the results illustrate that the dispersion condition can be better when the solution blending method was employed. The investigation of the effective activation energy on the relative extent crystallization implies that the agglomeration of copper nanoparticles can facilitate the crystallization of the LDPE, while the well-dispersed copper nanoparticles act as obstacles since the motion of the LDPE molecular chains is limited. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012