AbstractThe melting behavior of PPS (polyphenylene sulfide) and its blends with PSF (bisphenol A polysulfone) and PEK‐C (polyetherketone with phthalidylidene groups) are investigated with DSC technique. It is found that, with a rise in melt temperature Tmelt and melt time tmelt, the intensities of the lower melting peaks of PPS increase while those of the upper ones decrease or disappear in some cases, which can be attributed to the obstructive effect of branching or crosslinking of PPS macromolecules on the crystallization of PPS at higher temperature. As the annealing crystallization temperature increases, both the peak temperatures and intensities of the lower melting peaks of PPS increase. PSF and PEK‐C have no influence on the lower melting peaks of PPS but are unfavorable to the crystallization of the higher melting species. The double melting behavior of the PPS component in the blends is much more susceptible to the changes in Tmelt and tmelt than that of neat PPS. © 1994 John Wiley & Sons, Inc.