Research on Semi-Rigid Wearable Structure Based on Shape Memory and Self-Fusion Mechanism

This study presents a composite material that combines shape-memory function with a thermal self-fusing mechanism, designed for use in semi-rigid wearable structures. The material was prepared using a polyurethane-based matrix containing heat-activated bonding agents. When heated to 70 °C, the stiffness changed from 2.8 MPa to 24.5 MPa. A total of 30 samples were tested. The shape recovery reached over 96% within three minutes, and the bonding strength after fusion reached 4.8 MPa. Mechanical tests showed that the material maintained stable stiffness and bonding performance after 100 heating cycles, with less than 5% change in stiffness and less than 10% loss in bonding strength. Compared to control samples without bonding function, the proposed system showed better structural recovery and durability. These results suggest that this material may be used in wearable systems such as exoskeleton joints or support devices that require repeated stiffness changes and reliable reattachment between parts.