Ethylene/propylene elastomer (EPM), hydrogenated butadiene/acrylonitrile rubber (HNBR) and their mixts. were modified by addn. of 2-isopropenyl-2-oxazoline (IPO), filled with SiO(2) and vulcanized with (PhCMe(2)O)(2) at 160 degrees C. The vulcanizates were studied for mech. properties (tensile strength, elongation at break, tearing strength) and swelling ability. The addn. of MO (up to 7%) resulted in an increase in the elasticity modulus. An increase in the tensile and tearing strength was clearly obsd. only in the vulcanizates of the EPM/HNBR blends.