A Polymer System with Ultra‐High Molecular Potential Energy

In contrast to small molecules, macromolecules exhibit distinctive characteristics due to their higher potential energy (EP). These include elevated viscosity, enhanced tensile strength, cohesiveness, and stability. The EP of macromolecules can be modulated through the design of side groups, but this approach may also alter chemical properties. This study introduces an α‐methylation strategy that significantly enhances EP without modifying the structure of these side groups. This increase in EP induces a transition in the rheological behavior of polymer systems from a rubbery to a glassy state. Concurrently, it improves hygrothermal tolerance without changing dynamic bond groups. The application of this ultra‐high EP strategy results in substantial enhancements in traditional acrylic adhesives: a 1500% increase in adhesion strength and a 33200% rise in adhesion modulus when exposed to hot water. Polymer is endowed with a shape memory function due to ultra‐high EP. With the dual interface locking of this function, the adhesion strength can be increased by 70%. This ultra‐high EP strategy provides a possible explanation for the origin of vitrification in polymeric systems.