Ultralow-Temperature-Tolerance Adhesive with Excellent Toughness and Record-High Strength

With the in-depth exploration of extreme environments in polar, mountainous areas, and outer space, the demand for ultralow temperature resistant adhesives is increasing. However, for most adhesives used, represented by epoxy and acrylic resins, this is almost impossible due to their extensive intermolecular interaction and rigid three-dimensional (3D) network structure. Herein, an adhesive with a well-designed hard–soft phase separation structure has been developed in this work, which exhibits excellent bonding strength and debonding performance when bonded to metals (stainless steel and aluminum) and nonmetallic materials (polycarbonate) at −80 °C. The bonding strength and debonding energy with stainless steel reached 35.7 MPa and 61.16 kN/m, respectively, which is 5 times higher than those reported in the literature. Moreover, the adhesive exhibits good stability after 10 cycles of rapid cooling and heating between −196–50 °C. Finally, the mechanism behind the excellent bonding was verified, which stems from the strong polarity of the hard segments and the hardening of the soft segments.