Interchain crosslinking in a grafted low-density polyethylene and millable polyurethane blend is reported. The interchain crosslinking was studied by torque rheometry and IR spectra. The mechanism of interchain crosslinking was suggested based on the IR spectra. Interchain crosslinking improves thermal stability, which was measured by differential scanning calorimetry. Tensile strength increased but the swelling coefficient decreased with increased interchain crosslinking. The degree of interchain crosslinking is higher for the glycidyl acrylate grafted sample than for the maleic anhydride grafted sample. (C) 2004 Wiley Periodicals, Inc.