AbstractA series of hydroxy‐terminated polybutadiene (HTPB) polyureas modified with different liquid polysulfide content was synthesized and their structure and oil‐resistant properties were studied by attenuated total reflectance–FTIR spectroscopy, dynamic mechanical analysis, isothermal aging and differential scanning calorimetry, stress–strain analysis, oil absorption, and oil‐resistance test. The results showed that polysulfide–polybutadiene polyureas retained low temperature flexibility and had lower oil absorption and better oil resistance than that of HTPB‐based polyureas. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2672–2675, 2003