The article presents a comparative study regarding the magnetic field influence intervened during styrene copolymerization with 2,3-epoxypropyl methacrylate using a radical emulsion polymerization procedure. The registered magnetokinetic effects were evidenced for different reaction compositions and temperatures. The field effect influenced the conversion, the polymerization rate, and activation energy of polymerization process. An efficiency of magnetic field from the kinetic parameters has been established. (c) 2007 Wiley Periodicals, Inc.