Trapped entanglements in polymer networks: formation and characterization

The presence of entanglements in polymer networks has been known since the 1940s. These topological crosslinks have been found to strongly affect mechanical properties of the materials, including stiffness, extensibility, and toughness. However, control over the entanglement density and topology remains a challenge. Furthermore, entanglements are invisible to conventional chemical characterization methods, rendering their characterization a challenge in its own right. Recent endeavors in the realm of polymer entanglements have focused on unraveling the nature of entanglements and leveraging this knowledge to enhance the mechanical properties of soft materials. This review covers the latest breakthroughs in controlling and characterizing the formation of trapped entanglements in polymer networks and offers an outlook on the trajectory of this evolving field.