Fireproof\nCavity\nStructure with Enhanced Impact Resistance\nand Thermal Insulation toward Safeguarding

Developing\ndevices emphasizing safety protection is becoming\nincreasingly\nimportant due to the widespread occurrence of impact damage and thermal\nhazards. Herein, the F-SSG/TPU-based circular cavity structure (FC)\nis developed through a convenient and efficient template method, which\ncan effectively achieve anti-impact and thermal insulation for protection.\nThe flame-retardant shear stiffening gel/thermoplastic urethane (F-SSG/TPU)\nis synthesized through the dynamic interaction between the SSG, TPU,\nand modified ammonium polyphosphate (APP@UiO-66-NH<sub>2</sub>) by\nthermo-solvent reactions. The developed FC can dissipate the impact\nforce from 4.19 to 0.99 kN at 45 cm impacting heights, indicating\ngood anti-impact performance. Moreover, the thermal insulation test\ndemonstrates that the FC achieves a temperature drop of 76 °C\nat 160 °C attributed to the unique cavity structure design. Under\nthe continuous shock of high-temperature flame, FC remains intact,\nand its performance is almost undamaged. These results elaborate that\nthe designed FC can effectively resist various damage, such as high-temperature\nshock and collision. Then, a wearable wristband integrated with FC\nis developed which exhibits superior impact resistance and heat insulation\nproperties compared with commercial wristbands. In short, this cavity\nstructure based on high-performance F-SSG/TPU material shows promising\npotential applications in the protection field.