Viscoelasticity-controllable dynamic borate polydimethylsiloxane networks for enhancing energy dissipation of elastomers

Abstract

Borosiloxane-based materials, such as polyborosiloxane (PBS) are ideally utilized as impact-protective materials due to their shear-stiffening behavior, providing effective protection against injury. Current strategies rely on blending them with functional fillers or scaffolds to enhance impact-protective performance or achieve specific functionalities. However, the unclear structure-property relationships of borosiloxane-based materials have hindered their further development. Herein, we utilize viscoelasticity-controllable dynamic borate PDMS networks (PPDBS) for constructing PPDBS/PDMS double-network elastomers (SSEs) that exhibit excellent energy dissipation properties. The ultrahigh energy dissipation characteristics of SSEs are attributed to the rapid characteristic relaxation and high internal friction inherent to the network. We found that SSEs not only exhibit excellent damping properties (tan δ > 0.3) over a broad frequency (0.01-50 Hz) and temperature (−20-140 °C) range, but also demonstrate superior impact-protective performance compared with most commercial materials, including PBS. This work opens up a new avenue for the design of high-performance impact-protective and damping materials.