This research achieves a streamlined synthesis of end-functionalized thermoresponsive polymers via the combination of bulk reversible addition–fragmentation chain-transfer (RAFT) polymerization and quasi solvent-free Passerini three-component reaction (3CR) for the modification of chain-end groups. The RAFT polymerization of poly(ethylene glycol) methyl ether acrylate (mPEGA) and di(ethylene glycol)ethyl ether acrylate (DEGA) initiated by aldehydes featuring chain transfer agents proceeded under solvent-free conditions to afford aldehyde end-functionalized P(mPEGA-co-DEGA)s with the target molecular weight and moderate polydispersity index (Đ) value of ~1.4. Furthermore, the obtained aldehyde end-functionalized P(mPEGA-co-DEGA) was subjected to Passerini-3CR under quasi solvent-free conditions, which proceeded with >80% aldehyde conversion to afford P(mPEGA-co-DEGA) end-functionalized with α-acyloxy amides. The resulting α-acyloxy amide end-functionalized P(mPEGA-co-DEGA) showed critical solution temperature behaviors in water different from the parental polymer. In addition, the bulk RAFT polymerization and Passerini chain-end functionalization processes were combined in a one-pot process to provide a streamlined protocol that enables easy access to end-functionalized thermoresponsive polymers within 72 h with minimal use of solvents and reactants.

本研究通过本体可逆加成-断裂链转移 (RAFT) 聚合和用于修饰链端基团的准无溶剂帕塞里尼三组分反应 (3CR) 相结合，实现了末端官能化热响应聚合物的流线型合成。由具有链转移剂的醛引发的聚（乙二醇）甲基醚丙烯酸酯（mPEGA）和二（乙二醇）乙基醚丙烯酸酯（DEGA）的 RAFT 聚合在无溶剂条件下进行，得到醛末端官能化的 P(mPEGA- co- DEGA)s 具有目标分子量和中等多分散指数 ( Đ ) 值为 ~1.4。此外，获得的醛端功能化 P(mPEGA- co-DEGA) 在准无溶剂条件下进行 Passerini-3CR，醛转化率 >80%，得到 P(mPEGA - co -DEGA) 末端功能化的 α-酰氧基酰胺。所得α-酰氧基酰胺末端官能化的P(mPEGA- co- DEGA)在水中表现出不同于母体聚合物的临界溶液温度行为。此外，本体 RAFT 聚合和 Passerini 链端功能化过程结合在一锅法中，以提供一种简化的协议，可以在 72 小时内轻松访问端部功能化的热响应聚合物，同时使用最少的溶剂和反应物。