Use of a styrene derivative of formula wherein R 1 is selected from the group consisting of: a) a single bond; b) -(CH 2) n -, wherein n represents an integer from 1 to 12; c) -(CH 2 CH 2 Y) n -, wherein n represents an integer from 1 to 12, and Y can independently be oxygen or sulfur; d) -CH 2 -(CH 2 CH 2 Y) n -CH 2 -, wherein n represents an integer from 1 to 12, and Y can independently be oxygen or sulfur; e) -(CH 2 CH 2 NR) n -, wherein n represents an integer from 1 to 12, and R can independently represent an alkyl group containing from 1 to 10 carbon atoms, or an aryl or aralkyl group containing from 6 to 10 carbon atoms; f) -CH 2 -(CH 2 CH 2 NR) n -CH 2 -, wherein n represents an integer from 1 to 12, and R can independently represent an alkyl group containing from 1 to 10 carbon atoms, or an aryl or aralkyl group containing from 6 to 10 carbon atoms; wherein R 2 and R 3 can be the same or different and represent an alkyl group containing from 1 to 10 carbon atoms, or an aryl or aralkyl group containing from 6 to 10 carbon atoms; and R 4 and R 5 can be the same or different, and each R 4 and R 5 independently represents an alkyl group containing from 1 to 10 carbon atoms, or an aryl or aralkyl group containing from 6 to 10 carbon atoms, in the production of an elastomeric copolymer. wherein R 1 is selected from the group consisting of: a) a single bond; b) -(CH 2) n -, wherein n represents an integer from 1 to 12; c) -(CH 2 CH 2 Y) n -, wherein n represents an integer from 1 to 12, and Y can independently be oxygen or sulfur; d) -CH 2 -(CH 2 CH 2 Y) n -CH 2 -, wherein n represents an integer from 1 to 12, and Y can independently be oxygen or sulfur; e) -(CH 2 CH 2 NR) n -, wherein n represents an integer from 1 to 12, and R can independently represent an alkyl group containing from 1 to 10 carbon atoms, or an aryl or aralkyl group containing from 6 to 10 carbon atoms; f) -CH 2 -(CH 2 CH 2 NR) n -CH 2 -, wherein n represents an integer from 1 to 12, and R can independently represent an alkyl group containing from 1 to 10 carbon atoms, or an aryl or aralkyl group containing from 6 to 10 carbon atoms; a) a single bond; b) -(CH 2) n -, wherein n represents an integer from 1 to 12; c) -(CH 2 CH 2 Y) n -, wherein n represents an integer from 1 to 12, and Y can independently be oxygen or sulfur; d) -CH 2 -(CH 2 CH 2 Y) n -CH 2 -, wherein n represents an integer from 1 to 12, and Y can independently be oxygen or sulfur; e) -(CH 2 CH 2 NR) n -, wherein n represents an integer from 1 to 12, and R can independently represent an alkyl group containing from 1 to 10 carbon atoms, or an aryl or aralkyl group containing from 6 to 10 carbon atoms; f) -CH 2 -(CH 2 CH 2 NR) n -CH 2 -, wherein n represents an integer from 1 to 12, and R can independently represent an alkyl group containing from 1 to 10 carbon atoms, or an aryl or aralkyl group containing from 6 to 10 carbon atoms; wherein R 2 and R 3 can be the same or different and represent an alkyl group containing from 1 to 10 carbon atoms, or an aryl or aralkyl group containing from 6 to 10 carbon atoms; and R 4 and R 5 can be the same or different, and each R 4 and R 5 independently represents an alkyl group containing from 1 to 10 carbon atoms, or an aryl or aralkyl group containing from 6 to 10 carbon atoms,