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In this work, we demonstrate the controlled synthesis of graft and branched copolymers using one-pot (batch) or one-pass (flow) processes without intermediate purification. The formation of poly­(methacrylate) copolymers with pendent reversible addition–fragmentation chain transfer (RAFT) agent functionalities was performed using a selective photoactivation approach in the first step, specifically via green light-mediated direct photoRAFT polymerization. A nonselective photoinduced chain extension using red light-triggered photoinduced energy/electron transfer (PET)-RAFT polymerization was then performed to provide tailored graft copolymers. Notably, the application of this protocol to a flow process with two spatially segregated unit operations provides a route to independent control of the backbone-forming step (unit operation one) and the subsequent chain extensions (unit operation two). By alternating the light sources in both unit operations between the On and Off states, a range of macromolecular architectures could be prepared from the same starting materials. To demonstrate the power of this divergent approach, a series of graft copolymers with tailored backbone lengths and number and molecular weight characteristics of side chains were synthesized using the same starting materials by a single pass process. Additionally, the polymer architecture was switched between graft and hyperbranched architectures via external manipulation of light sources.

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The combination of high-throughput (HTP) processes and flow-mediated synthesis allows large data sets to be generated quickly while also permitting large quantities of materials to be prepared in a continuous fashion. In this work, the benefits of wellplate-based HTP polymerization and flow-mediated chemistry are used to streamline the screening and upscaling of value-added biomedical materials through a robust photopolymerization strategy, namely, photoinduced electron/energy transfer-reversible addition− fragmentation chain transfer (PET-RAFT) polymerization. A library of potential antimicrobial polymers was generated from an initial pool of monomers and tested for their activity against Pseudomonas aeruginosa (PA). The antimicrobial activity of the most promising candidates was then elucidated through structure−property analyses performed via both plate and flow polymerization processes; interestingly, terpolymerization of mixtures of acrylate and acrylamide monomers produced terpolymers with gradient architectures due to their reactivity ratios, which ultimately dictated the resulting antimicrobial activity. Finally, the polymers found to have the highest antimicrobial activity were upscaled in a flow reactor. This workflow provides a general and highly accessible methodology for the discovery and synthetic scaling of optimized polymer structures for biomedical applications such as new antimicrobial agents.