Architectural Precision in Sequence-Controlled Terpolymerization from Epoxide/Aziridine/Phthalic Thioanhydride Mixture

The monomer sequence serves as a critical determinant of a polymer’s physicochemical properties. While traditional copolymerization processes are dictated by inherent monomer reactivity disparities, the emerging paradigm of catalytic precision engineering offers unprecedented opportunities to orchestrate monomer incorporation sequences beyond thermodynamic constraints. Notably, recent efforts have concentrated on developing catalytic systems with chemo- and stereoselectivity orthogonal to monomer polarities, establishing dynamic polymerization platforms that enable real-time sequence editing through manipulation of catalysts. Herein, we disclose a modular catalytic strategy enabling atom-level control over poly(thioester amide) sequences through organoammonium-mediated ring-opening copolymerization (ROCOP) of Cbz-aziridine and phthalic thioanhydride under ambient conditions. Furthermore, we develop a dual-catalytic system that integrates salenAl(III)Cl and PPNOAc, establishing a dynamic multinucleophilic platform that circumvents traditional monomer reactivity hierarchies. Of importance, systematic manipulation of catalysts in epoxide/aziridine/PTA terpolymerization achieves unprecedented continuum control across gradient, statistical, and inverse gradient microstructures in poly(thioester amide-thioester)s. This synthetic approach establishes a generalizable platform for fabricating compositionally equivalent copolymers with digital precision and significantly enhances the mechanistic understanding of polymer physics while creating principles for high-impact applications ranging from adaptive biomaterials to intelligent responsive systems.