A comprehensive model was developed using the method of moments to describe the atom transfer radical copolymerization (ATRcoP) of methyl methacrylate and 2-(trimethylsilyl) ethyl methacrylate in a train of continuous stirred-tank reactors (CSTRs). The use of a train of CSTRs effectively decreases the residence time distribution and molecular weight distribution. Two different constraint conditions (i.e., constant feeding flow rate and constant total average residence time) were simulated. At constant feeding flow rate, the monomer conversion and average molecular weight are significantly improved by increasing the number of CSTRs in the train. Moreover, a constant total average residence time increases the productivity of copolymers with the increase in the number of CSTRs in the series. Thus, a train of CSTRs can be used to produce copolymers continuously with consistent quality. This method is important in obtaining a balance between the quality and quantity of the copolymer production for ATRcoP. POLYM. ENG. SCI., 2014. © 2014 Society of Plastics Engineers