Mechanically Robust and Wear‐Resistant 3D‐Printable Polyurethane Elastomers Through UPy‐Based Supramolecular Reinforcement

The pursuit of adequate mechanical robustness, particularly exceptional toughness and abrasion resistance, in polyurethane elastomers is a prerequisite for any application, yet the development of such a functionally structural elastomer presents a prodigious challenge. Herein, a photocurable elastomer is engineered through an innovative supramolecular engineering strategy that leverages dynamic quadruple hydrogen bonding (QHB), achieved by incorporating 2‐amino‐5‐(2‐hydroxyethyl)‐6methylpyrimidin‐4‐ol (UPy) moieties into the polyurethane backbone. The robust microphase‐separated architectures within elastomers arise from UPy dimer self‐assembly via strong QHB, and systematically increasing the UPy content promotes hard‐phase aggregation, enhances H‐bonding density, and improves thermal stability. The resulting optimal elastomer demonstrates exceptional mechanical performance. The dynamic nature of the supramolecular network further endows the elastomer with exceptional abrasion resistance, facilitating energy dissipation and load bearing. To demonstrate this concept, we fabricated an artificial polyurethane meniscus model from the photosensitive prepolymer via vat photopolymerization 3D printing, achieving wear‐resistant lubrication. This research advances the effectiveness of a strategic supramolecular design approach for creating high‐performance elastomers that integrate multifunctionality with structural complexity.