High-Performance Flow Chemistry Platform for Scalable Continuous Synthesis of Branched Block Copolymers with Precise Chain Structures

Cutting-edge research has primarily focused on flow synthesis of linear block copolymers, lacking the ability for manipulating chain architectures for more extensive applications. Herein, we develop a flow chemistry platform for the continuous microflow synthesis of bottlebrush block copolymers (BBCPs) using a grafting-through method. This involves performing ring-opening metathesis polymerization (ROMP) of two different macromonomers within two microfluidic reactors connected in series. The microflow environment allows for complete monomer conversion within a few tens of seconds, benefiting from the superior mixing efficiency achieved in Z-shaped channels as indicated by both theoretical simulations and experimental results. Consequently, a library of well-defined BBCPs of up to 528 distinct samples can be produced within one day through automation of the continuous procedure, while keeping precise control on degree of polymerization (DP<4) and polydispersity indices (PDI<1.2). The synthetic method is generally applicable to different macromonomers with different compositions and contour lengths, yielding libraries of branched block copolymers with great diversity in physiochemical properties and chain architectures. This work presents a powerful platform for high-throughput production of branched copolymers, significantly lowering the costs of the materials for real applications.