Patent ID: 7488786

Claim:
An emulsion polymerization process that comprises: (1) preparing a aqueous polymerization medium which is comprised of (a) at least one monomer, (b) a polymerization control agent, an emulsifier, and optionally a water insoluble cosolvent, wherein the emulsifier is prepared in-situ within the aqueous polymerization medium; and (2) initiating polymerization of said monomer within the aqueous polymerization medium, wherein the polymerization control agent is of the structural formula: (Z)-(R 1 ) n , wherein n represents an integer from 1 to about 6; wherein Z represents an aromatic or aliphatic moiety containing from 1 to about 20 carbon atoms; wherein R 1 represents a moiety of the structural formula: wherein R 2 represents a moiety selected from the group consisting of alkyl groups, alkenyl groups, alkynyl groups, aryl groups, heteroaryl groups, and alkaryl groups; wherein the alky groups, alkenyl groups, alkynyl groups, aryl groups, heteroaryl groups, and alkaryl groups can be substituted, unsubstituted, linear, branched or cyclic; and wherein Ar represents a p-alkoxyphenyl group having an alkoxy moiety that contains from 1 to 8 carbon atoms.