The result of chemical modification of unsaturated elastomers such as poliisoprene, butadiene styrene and butadienenitrile sopolimers by derivatives of chloroacetic acids have been summed up. Modified samples of rubbers showed that irrespective of the structure of macromolecular chain of polymers, the modification reaction has a total character – modifying agent is added on multiple bond of elastomer with formation of g-butyrlactone in the case of trichloroacetic acid; thus, the modification reaction rate of poliisoprene is largest, an introduction of aryl substituents rate by 1.2÷1.4 times or nitrile group into chain of macromolecule leads to the decrease of reaction rate by 1.5÷1.9 times. It showed that application of modifying agent is instrumental in the substantial improvement of properties of vulcanization that allows to extend the spheres of the use of the materials obtained.