Vector Decomposition-Based Model Linking Filler Orientation to Dynamic Network Kinetics: From Experiment to Theoretical Prediction

Herein, we propose a strategy to spatially regulate dynamic bond exchange in epoxy vitrimer by introducing graphite flakes (GFs) fillers with multi-angle orientations ( θ = 0°–90°). Through a hot-pressing-induced alignment technique, GFs were arranged in five angular configurations within a disulfide-based vitrimer matrix. Stress relaxation analysis revealed a bidirectional regulatory effect: as θ increased from 0° to 90°, the characteristic relaxation time ( τ ) at 180°C rose from 17.2 to 28.0 s, while the activation energy ( E a ) decreased from 97.7 to 90.0 kJ/mol. By integrating vector decomposition and Arrhenius kinetics, we established a dual-exponential decay model linking sinθ to E a and τ , quantitatively describing orientation-dependent dynamics. This work pioneers the spatial manipulation of vitrimer network reconfiguration, offering a paradigm for anisotropic smart materials.