Thanks to this versatility, self-assembling polymeric structures are designed either to respond to triggers and perform specific applicative tasks, or to investigate the influence of structural variables on the responsivity of polymers. As a result, MSR polymers are obtained from diverse combinations of commercial or specially synthesized building blocks arranged at will into desired sequences and architectures. Furthermore, “click” reactions are used to combine macromolecular precursors or to introduce specific functional groups in the target structure. Such control can afford materials with well-defined responses to physical, chemical, and biological external stimuli. RDRPs are now robust, versatile, relatively user-friendly and even interconvertible, thus allowing control over composition, sequence, and topology of polymers. In fact, along more than 40 years of extensive research, RDRPs have boosted the synthesis of stimuli-responsive polymers. In this review article, we survey the 2016–June 2021 scientific literature on the synthesis of multi-stimuli responsive (MSR) polymers, the main focus being on reversible deactivation radical polymerization techniques (RDRPs, also known as controlled radical polymerizations). This as-developed strategy is proved to be an efficient technology to produce well-defined polymers without complicated processes of products separation from solvent and residual monomer removal. oxidative quenching cycle for RAFT, reductive quenching cycle for ATRP, photogenerated radical species for ITP) to initiate and mediate the solvent-free polymerizations and ultrasonication was used as an effective process intensification method to improve the diffusive of photocatalysts and their derivatives to alleviate the diffusional limitations for keeping good control up to high monomer conversion. Kinetic experiments and mechanistic insights confirmed that light triggered different photocatalytic pathways (e.g. The solvent-free polymerizations of (meth)acrylate under different conditions were performed with good control even at high monomer conversion (>90%), yielding polymers with low values of dispersity and retention of chain-end functionality. All rights reserved.įocusing on energy-saving and environmentally-friendly polymerization engineering, ultrasonication and light were employed as coupled physical stimuli to regulate solvent-free reversible addition fragmentation chain transfer polymerization (RAFT), atom transfer radical polymerization (ATRP) and iodine transfer polymerization (ITP). We believe that this work should be attractive for polymer engineering, and informative to create more flow polymerization techniques toward on‐demand control of diverse polymer characters. For copolymers, chemical compositions could be readily regulated besides MWDs with the droplet‐flow platform. Notably, the computer‐aided platform has streamlined an automatic and high‐throughput pathway to prepare polymer libraries of tunable MWDs. Synthetic advantages of this photo‐flow polymerization allow controlled chain‐growth to yield a variety of polymers of tunable MWDs in a broad range (Ð ≈ 1.1‐1.9) with predetermined molecular weights (Mn ≈ 4‐30 kDa) and good chain‐end fidelity. In this work, we demonstrate the development of a computer‐aided droplet‐flow system that combines photo‐mediated reversible‐deactivation radical polymerization (RDRP) and chain transfer agent (CTA) diffusion strategy to enable facile MWD control for the first time. Molecular weight distribution (MWD) is fundamental for polymer analysis, which influences many important properties of polymeric materials.
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