Dynamic Borate-Driven Polyphenol Nanophase Assembly for Acrylate Vitrimers with Self-Healable, Strain-Stiffening, and Fluorescent-Responsive Functions

Vitrimer materials with self-healing, strain-stiffening, and fluorescence-responsive abilities have found increasing applications in various fields. However, the integration of these features into a single vitrimer system remains challenging. Herein, we propose a multifunctional acrylate vitrimer based on dynamic borate-driven polyphenol nanophase assemblies. Interestingly, the in-situ-assembled nanostructures showed polyphenol-dependent shapes in acrylate vitrimers, forming particle-like shapes at low polyphenol contents and fiberlike shapes at higher contents. The resultant vitrimer material with borate-driven polyphenol nanophases exhibited good stretchability (1870%), a high strain-stiffening index (maximum 3.48), and excellent self-healing efficiency (93%). The rheological results of the acrylate vitrimer revealed that the borate-driven polyphenol nanophases yielded excellent network integrity, evidenced by the stable solid elasticity (ε = 500%) recoverable for at least five times. The elastic-viscous transition of acrylate vitrimers from rheological rubber plateaus was due to significant boronic ester exchange reactions and insufficient reconstruction time during the exchange process. The acrylate vitrimers also exhibited an energetic fluorescence intensity recovery for multiple pH cycles and could be used to sense pH variations. This study demonstrates a new design strategy for fabricating high-performance acrylate vitrimers using tunable dynamic borate-driven nanostructures that offer opportunities for the advancement of intelligent materials across a wide range of applications.