Beyond Molecular Determinism: State-Convergent Polymerization as a Functional Design Principle Under Chemical Complexity.

Polymeric materials are traditionally designed by prescribing molecular structures and reaction pathways. However, many functional polymers-exemplified by natural melanins and synthetic polydopamine-operate reproducibly despite persistent molecular heterogeneity and ill-defined architectures. Here, I propose state-convergent polymerization (SCP) as a design logic for polymeric materials formed under chemical complexity, in which polymerization is defined by convergence toward a functional material state rather than a discrete molecular structure. In SCP, polymer formation emerges from dynamically evolving pools of reactive motifs confined within environmentally bounded chemical state spaces. Crucially, these state spaces are chemically addressable through experimentally accessible variables such as pH, redox conditions, oxygen availability, and interfacial confinement, enabling multiple reaction trajectories to coexist while enforcing functional convergence. By decoupling polymer function from molecular determinism, SCP provides a materials design framework for materials operating under chemical complexity, including biointerfaces, adaptive coatings, and open-system polymerization processes. This perspective reframes polymer synthesis from structure prescription toward state engineering, offering actionable principles for designing robust functional materials beyond molecular precision.