New polyurea polymer compositions are disclosed which are prepared by a polyaddition reaction of a polyisocyanate with a compound having the general formula: ##STR1## wherein X is oxygen or sulfur and R represents a group of the formula: ##STR2## wherein R.sub.1 to R.sub.4 are hydrogen or halogen and B stands for a divalent polyalkylene ether group or a polyalkylene thioether group such as it is obtained by removal of the hydroxyl or mercapto groups from a polyalkylene ether diol or from a polyalkylene thioether dithiol of a molecular weight of 100 to 15000. The polymer composition are useful for the formation of vehicle tires of all types including plastic components for parts of wheels, for conveyor belts, fasteners and shoe soles.