Ultra-wide damping temperature range polyurethane elastomer enabled by an asymmetrically structured chain extender with double disulfide bonds

Conventional polymer damping materials are extensively utilized to mitigate vibration and noise in various fields, yet suffer from the drawback of a narrow effective damping temperature range. Herein, we innovatively synthesized an asymmetrically structured chain extender (AIS) with double disulfide bonds that provided polyurethane elastomer (PUE) with ultra-high energy dissipation over a wide temperature range, which was unattainable by conventional chain extenders. This was achieved by enhancing the bond exchange rate of dynamic disulfide bonds in the PUE. Specifically, the asymmetric structure of AIS was strategically designed to disrupt the regularity of the hard segments of the PUE, enabling the disulfide bonds to break and reorganize efficiently, thus depleting mechanical energy. The results demonstrated that the effective damping temperature range (Tan δ > 0.3) of the PUE cured by AIS can reach 130 °C (−15 °C–115 °C), which is 210 % higher than that of the matrix, and a stable damping plateau was observed in the region from room temperature to high temperature. Moreover, the introduction of AIS significantly enhanced the mechanical properties of the PUE. This study encourages further investigation and application of disulfide bonds in the field of damping.