Flow chemistry presents many advantages over batch processes for the fast and continuous production of polymers under more robust, safer, and easily scalable conditions. Although largely exploited for chain-growth polymerizations, it has rarely been applied to step-growth polymerizations (SGP) due to their inherent limitations. Here, we report the facile and fast preparation of an emerging class of nonisocyanate polyurethanes, i.e., CO₂-based poly(oxazolidone)s, by SGP in continuous flow reactors. Importantly, we also demonstrate that functional poly(oxazolidone)s are easily prepared by telescoping a flow module where SGP occurs with reagents able to simultaneously promote two polymer derivatizations in a second module, i.e., dehydration followed by cationic thiol–ene to yield poly(N,S-acetal oxazolidone)s. The functional polymer is produced at a high rate and functionalization degree, without requiring the isolation of any intermediates. This work demonstrates the enormous potential of flow technology for the facile and fast continuous production of functional polymers by SGP.

中文翻译：

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通过逐步生长聚合连续流动合成功能性不含异氰酸酯的聚恶唑烷酮


与间歇工艺相比，流动化学具有许多优势，可以在更稳健、更安全且易于扩展的条件下快速、连续生产聚合物。尽管主要用于链增长聚合，但由于其固有的局限性，它很少应用于逐步增长聚合（SGP）。在这里，我们报道了通过 SGP 在连续流动反应器中轻松快速地制备一类新兴的非异氰酸酯聚氨酯，即 CO ₂ 基聚（恶唑烷酮）。重要的是，我们还证明，通过伸缩流动模块可以轻松制备功能性聚（恶唑烷酮），其中使用能够在第二个模块中同时促进两种聚合物衍生化的试剂进行 SGP，即脱水，然后进行阳离子硫醇-烯以产生聚（ N,S-缩醛恶唑烷酮）。功能聚合物的生产速度和功能化程度都很高，无需分离任何中间体。这项工作展示了流动技术在 SGP 轻松快速连续生产功能聚合物方面的巨大潜力。