Viscoelasticity-Controllable Dynamic Borate Polydimethylsiloxane Network For Enhancing Energy Dissipation of Elastomers

Borosiloxane-based materials, such as polyborosiloxane (PBS) are ideally utilized as impact-protective materials due to the shear-stiffening behaviors, 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 a viscoelasticity-controllable dynamic borate PDMS network (PPDBS) for constructing PPDBS/PDMS double-network elastomers (SSEs) that exhibiting excellent energy dissipation property. The ultrahigh energy dissipation characteristic 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 property (tan δ＞0.3) over a broad frequency (0.01 Hz-50 Hz) and temperature range (-20 °C-140 °C), 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.