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The relationship between molecular structure and macroscopic function is a foundational principle in materials science, in which subtle molecular variations produce pronounced differences in strength, stiffness, and elasticity. In hydrogels, replacing static covalent bonds with dynamic covalent bonds (DCBs) creates newfound capabilities, including selfhealing and recyclability. Herein, how substitutional differences in dual DCB imine boronic ester crosslinkers, together with matrix pH, influence hydrogel properties was investigated. A comparison of orthoand para-imine boronic esters showed the formation of 3-amino-benzoxaborole heterocycles in hydrogels derived from 2-formylphenylboronic acid. Tautomerization to the heterocycle significantly enhanced hydrogel elasticity, despite a lower crosslinking density than hydrogels formed with 4formylphenylboronic acid. Two closed-loop end-of-life management pathways were also demonstrated. Reprocessing through self-healing was accomplished, with hydrogels regaining at least 90% of their original rheological properties. A fully circular recycling pathway was also established, recovering all starting materials for reuse, with recycled hydrogels achieving over 100% recovery of rheological properties. Overall, the presence of previously undisclosed 3-amino-benzoxaborole structures was demonstrated, expanding the understanding of formylphenylboronic acids in polymeric materials, and complete closed-loop pathways were designed to inspire researchers in materials circularity to demonstrate and validate the full end-of-life processes for the materials they develop.