Control over polymer architecture is a central challenge in chemistry that is key for the design and manipulation of material properties, to enable integration of macromolecules into potential applications. Numerous strategies have been employed to control polymer architecture, with one of the most elegant examples being catalyst walking, where a catalyst is able to migrate along a polymer backbone during polymerization. Ideally, this mechanism proceeds without catalyst dissociation from the growing polymer chain, thus allowing for control over molecular weight, sequence, and end-groups. Herein, we present the mechanism of catalyst walking in olefin polymerization and contrast it with catalyst transfer polymerization. We compare the advantages and limitations of each method and provide guidance for the future potential of catalyst walking in the synthesis of macromolecules.

对聚合物结构的控制是化学领域的主要挑战，这对设计和操纵材料特性至关重要，以使大分子能够集成到潜在的应用中。已经采用了许多策略来控制聚合物的结构，最优雅的例子之一是催化剂行走，其中催化剂能够在聚合过程中沿着聚合物主链迁移。理想地，该机理在没有催化剂从生长的聚合物链解离的情况下进行，从而允许控制分子量，序列和端基。在本文中，我们介绍了烯烃聚合中催化剂行走的机理，并与催化剂转移聚合进行了对比。