Six types of spherulite morphologies packed with polymorphic crystals and their growth kinetics in melt-crystallized poly(heptamethylene terephthalate) (PHepT) were characterized using polarized-light optical microscopy (POM), Fourier transformed infrared microspectrometry (micro-FTIR), differential scanning calorimetry (DSC) and atomic-force microscopy (AFM). Two maximum melting temperatures (T-max), a higher 150 degrees C and a lower 110 degrees C, were used to melt the initially crystallized PHepT of either alpha- or beta-crystal. The high T-max was enough to melt all nuclei, but the lower T-max was considered as near or slightly below the equilibrium melting temperatures of these two cells (if estimated by nonlinear methods). When crystallized at various T-c from these two T-max's, PHepT can exhibit as many as six types of spherulites (Ring Type-I, -II, -III, Maltese-cross Type-1, -2, and -3) owing to different nucleations. Ring Type-I, Maltese-cross Type-1 and -3 spherulites are packed of the sole beta-crystal, while Ring Type-II, -III and Maltese-cross Type-2 spherulites are attributed to the sole alpha-crystal. However, as the PHepT polymorphic cells are related to T-c, such correlations between the crystal cells and spherulite types (ring or ringless) cannot be ruled out to be a coincidence. (C) 2010 Elsevier Ltd. All rights reserved.