Hybrid block copolymers of polyesters/polycarbonates and polypeptides synthesized via one-pot sequential ring-opening polymerization

Abstract

An efficient approach toward one-pot sequential ring-opening polymerization (ROP) of cyclic esters/carbonates and N-carboxyanhydride (NCA) monomers, differing in reactivity and type of propagating group, is presented. In the first step, a polyester/polycarbonate is synthesized using methanesulfonic acid as a catalyst. After the completion of polymerization NCA is added to the reaction mixture. Methanesulfonic acid successfully catalyzes the initiation step of ROP of NCA and simultaneously prevents the chain propagation by protonation of the formed amine groups. After the completion of NCA initiation, the propagation is started by addition of N-ethyldiisopropylamine as a base to prepare the hybrid block copolymers of polyester/polycarbonate and polypeptide in a one-pot manner.