美国北卡罗来纳大学Wei You团队报道可逆加成-断裂链转移逐步聚合。相关研究成果于2021年9月28日发表在《美国化学会杂志》。

可逆加成-断裂链转移（RAFT）聚合自发现以来，由于其结构的精确性、通用性和高效性而得到了广泛的探索。然而，聚合物主链缺乏可调性限制了某些应用。

该文中，研究人员通过采用单体与RAFT试剂的高选择性插入过程，协同结合RAFT和逐步聚合机理，以实现RAFT逐步聚合。RAFT逐步生长聚合物的一个独特特征是，每个主链重复单元带有一个悬垂RAFT试剂，该试剂随后可在第二聚合步骤中接枝侧链，并提供分子刷聚合物。借助于可切割的主链功能，研究人员展示了在刺激下将得到的刷子状聚合物转化为尺寸均匀的线性链。

附：英文原文

Title: Reversible-Addition Fragmentation Chain Transfer Step-Growth Polymerization

Author: Joji Tanaka, Noel Edward Archer, Michael Jeffery Grant, Wei You

Issue&Volume: September 28, 2021

Abstract: Reversible-addition fragmentation chain transfer (RAFT) polymerization has been widely explored since its discovery due to its structural precision, versatility, and efficiency. However, the lack of tunability of the polymer backbone limits some applications. Herein, we synergistically combine RAFT and step-growth polymerization mechanisms, by employing a highly selective insertion process of a single monomer with a RAFT agent, to achieve RAFT step-growth polymerization. A unique feature of the RAFT step-growth polymers is that each backbone repeat unit bears a pendant RAFT agent, which can subsequently graft side chains in a second polymerization step and afford molecular brush polymers. Enabled by cleavable backbone functionality, we demonstrate transformation of the resulting brushlike polymers into linear chains of uniform size upon a stimulus.

DOI: 10.1021/jacs.1c07553

Source: https://pubs.acs.org/doi/10.1021/jacs.1c07553