A Digitally Controlled Flow–Batch Platform for Reproducible Radical Copolymerization with Reduced Composition Drift

Free-radical copolymerization is widely used in industry to produce copolymers from diverse monomers, but transferring laboratory syntheses to manufacturing remains challenging because changes in mixing and heat-transfer conditions can alter polymer properties. Here, we report a digitally controlled flow–batch platform that integrates a micromixer, a heated tubular flow reactor, and batch reactors. In this configuration, the micromixer provides rapid and reproducible mixing, the flow stage provides rapid thermal initialization under low-conversion conditions, and the batch stage completes the reaction at high conversion while accommodating additional monomer dosing. Rapid mixing and heating in the flow stage mitigated the early-stage formation of very-high-molecular-weight polymer, while additional monomer dosing designed from initiator-decomposition kinetics suppressed composition drift during the batch stage. Together, these operations reduced the time-dependent variation in copolymer composition and molecular weight under high-conversion conditions. In a demonstration using four parallel batch reactors, the platform produced 1.97 kg of copolymer (dry basis) in an 8 h run. The proposed platform provides a practical process strategy for reproducible radical copolymerization in small-lot manufacturing of advanced polymer materials.