The effects of dynamic crosslinking on rheological, mechanical and dynamic mechanical properties of high density polyethylene (HDPE) and acrylonitrile butadiene rubber (NBR) blends have been evaluated with special reference to the effect of dosage of crosslinking agent. The morphology has been studied using scanning electron microscope. Both the microscopy and dynamic mechanical analysis indicate that the blends are immiscible and form two-phase structures. But it is evident that dynamic vulcanisation can be employed as a technological compatibilisation technique to get finer and stable morphology and improved mechanical properties. The rheological studies reveal that the dynamically vulcanised samples could be processed like thermoplastics.