Choi, Kyu Y.Butala, D.This paper describes a new approximation method to synthesize open loop control schemes for the control of copolymer composition and molecular weight in batch and semibatch polymerization reactors. The open loop control policies are derived from the transient response of the fictitious feedback control system obtained by numerical model simulations. The applicability of the proposed method is demonstrated through numerical examples.en-USTechnical Report