Polymerization of Methyl Methacrylate with Mn(acac)3 in the Presence of Organic Halides. Possibility of Molecular Weight Control of Polymer

Molecular weight control of the polymers in the polymerization of methyl methacrylate (MMA) by Mn(acac)3 in the presence of organic halide (RX) was investigated. In the polymerization of MMA with Mn(acac)3 and in the presence of methyl 2-bromopropionate (MBP), the relationship between the polymer yields and molecular weights of the polymers gave a straight line, and the line passed through the origin. The Mw/Mn was not so narrow, but the values of the Mw/Mn kept almost constant around 2.0–3.0 during the reaction, indicating that the molecular weight control of polymer was achieved in the polymerization of MMA with Mn(acac)3/MBP. When methyl bromoacetate (MBA) was used, some polymerization behavior was different from that of MBP. It was demonstrated that the structure of RX played an important role to control the molecular weight of the polymer in the polymerization of MMA with Mn(acac)3/RX. The effects of MMA concentration and reaction temperatures were observed. The poly(St-b-MMA) was synthesized by the polymerization of MMA using poly(St) obtained from the polymerization with Mn(acac)3/MBP.