A High‐Performance Damping Composite: Synergistic Wide Damping Temperature Range and Excellent Mechanical Properties Through an Interpenetrating Polymer Network

ABSTRACT Damping composites can significantly mitigate the damage caused by vibration. However, traditional damping composites exhibit a narrow damping temperature range due to their single matrix, providing high damping performance only near the glass transition temperature ( T g ). The incorporation of multiple matrix materials through blending can simply and effectively broaden the damping temperature range; however, this approach typically results in poor mechanical properties due to inadequate compatibility between the matrix materials. This study prepared a damping composite by constructing an interpenetrating polymer network (IPN) by polyborosiloxane (PBS) and phenyl silicone rubber (PSR). PBS forms a physically cross‐linked network via dynamic B‐O bonds, contributing wide damping temperature range. PSR forms a secondary network through covalent cross‐linking, providing structural support and excellent mechanical properties. This synergistic combination results in IPN composites with outstanding damping performance and mechanical properties. The prepared damping composite maintains effective damping (tan δ > 0.3) across an ultra‐wide temperature range: from −77°C to −30°C and from 31°C to 225°C, demonstrating a 431% enhancement over the blank sample. The IPN composite demonstrates impressive mechanical performance: a tensile strength of 4.2 MPa and an elongation at break of 720%. This study provides a viable strategy for fabricating high‐performance damping composites.