Synthesis of amino-functionalized polyester via ring-opening alternating copolymerization of glycidylamines with cyclic anhydrides†

Amino-functionalized polyesters (APEs) are a remarkable class of polymeric materials with a wide range of applications, e.g. as antibacterial materials, gene delivery carriers, and biodegradable plastics. However, the current APE synthetic pathway poses significant challenges in terms of structural diversity and control over polymerization. In this study, we explored the ring-opening alternating copolymerization (ROAC) of glycidylamines with cyclic anhydrides as a novel method of synthesizing APEs. The ROAC of N,N-dibenzylglycidylamine (DBGA) and phthalic anhydride (PA) successfully proceeded to yield the corresponding alternating copolymer poly(PA-alt-DBGA), with a typical molecular weight and dispersity of 5500–21 000 g mol⁻¹ and 1.10–1.62, respectively, using an alkali metal carboxylate or a phosphazene base as a catalyst. Kinetic and chain extension studies of the t-BuP₁-catalyzed ROAC revealed its controlled/living nature, which enabled us to produce block copolyesters comprising APE and polyethylene glycol and install a functional end-group using a functionalized alcohol initiator. In addition, we prepared several poly(cyclic anhydride-alt-glycidylamine)s with different main- and side-chain structures using different monomers. Based on the advantages of chain-growth polymerization and the wide monomer scope, the developed ROAC system may accelerate the investigation of novel APEs for use in different applications.