Self-Recoverable Dual-Network Silicon Elastomer Applied in Cell Adhesives

Dual-network filler-free silicon elastomers with excellent mechanical properties and high tensile strength (>3 MPa) were fabricated through physical and chemical cross-linking via Fe3+ ion coordination and aza-Michael addition, respectively. Dynamic mechanical analysis and loading–unloading tests were used to analyze the sacrificial bonds and dual networks in the elastomers. Continuous-wave electron paramagnetic resonance results revealed the incomplete coordination and similar chemical environment of Fe(III) ions in the elastomers. The coordination bonds dissipated energy, and the chemical cross-linking maintained the networks; they enhanced tensile strength jointly. The elastomers demonstrated favorable self and shape recoverability due to the dynamic reversibility of the coordination bonds and the stress of the chemical cross-linking in the reshaped elastomers. Such elastomers could be used as intelligent and sustainable materials. Moreover, the materials exhibited good biocompatibility and can be utilized as a type of cell adhesive in bioimaging.