PURPOSE: To produce a rubber having a polymer bing functional group without using any harmful co-solvent and without the necessity for solvent recovery.

CONSTITUTION: The production process comprises the emulsion polymerization of at least one functionalized monomer that contains a polymerizable vinyl group with at least one copolymerizable conjugated diene monomer selected from the group consisting of butadiene-1,3,2-chlorobutadiene-1,3, isoprene, piperylene and conjugated hexadienes at a temperature ringing from about 0°C to about 25°C, wherein the polymerization is conducted in the presence of from about 1 to about 70 pts.wt., per 100 pts.wt. total monomer, plasticizer. The plasticizer functions as a cosolvent/dispersant during the emulsion polymerization and additionally functions as a plasticizer for the final polymer product.