Reverse atom transfer radical polymerization of dimethyl itaconate initiated by a new azo initiator: AIBME

Reverse atom transfer radical polymerization (RATRP) was used to synthesize poly(dimethyl itaconate) (PDMI) using an AIBME/CuBr(2)/dNbpy system. The number average molecular weight (M(n)) of PDMI was as high as M(n) = 15 000 g mol(−1), the monomer conversion rate reached up to 70%, and the dispersity remained low (Đ = 1.06–1.38). The first-order kinetics of PDMI are discussed in detail. The AIBME initiator had a higher initiation efficiency than the AIBN initiator. As the ratio of initiator (AIBME) to catalyst (CuBr(2)) decreased, the M(n) and Đ of PDMI decreased. At 60 °C and 80 °C, the M(n) of PDMI was much higher than the theoretical number average (M(n,th)), and the Đ of PDMI broadened with the conversion rate. At 100 °C, the Đ of PDMI remained low, and the M(n) of PDMI was closer to the M(n,th). As the ratio of monomer (DMI) to initiator (AIBME) increased, the M(n) of PDMI changed little over time. These phenomena could be explained by the influence of the initiator and catalyst on polymerization kinetics.