Multiscale synergistic reinforcement strategy for ultrahigh specific damping composites via dynamic bonds and glass fibers

High-performance damping materials require effective utilization of damping source units and optimized mechanisms to maximize mechanical energy dissipation. In this study, a multiscale synergistic reinforcement strategy is developed to achieve an optimal balance between stiffness and damping by integrating nanoscale dynamic bonds and microscale stiffening effects. At the nanoscale, disulfide bonds are introduced to construct vitrimer networks, serving as additional damping source units. At the microscale, glass fibers act as rigid fillers to enhance stiffness while inducing matrix deformation-driven damping. The damping excitation mechanism of this hierarchical composite structure is elucidated through finite element analysis. Experimental results demonstrate that the prepared composites exhibit an ultrahigh loss modulus of up to 1148 MPa, significantly exceeding that of conventional engineering materials. This work provides a novel design approach for multiscale composites, facilitating the structural integration of high-performance damping materials for advanced manufacturing applications. Highlights Multiscale synergistic reinforcement strategy is proposed for ultrahigh specific damping. Ultrahigh loss modulus of 1148 MPa achieved in hierarchical composites. Multiscale design balances stiffness and damping via dynamic bonds and glass fibers. Disulfide bonds enhance damping via bond breaking and reformation. Glass fibers boost stiffness while driving matrix deformation to dissipate.