Low‐Outgassing Liquid Metal–Silicone Composites for Multifunctional Space Applications

ABSTRACT

Space‐grade elastomers provide critical sealing, adhesion, and damping functions in spacecraft but require low outgassing to avoid contamination of sensitive optical and electronic components. Silicone elastomers are widely adopted due to their environmental stability, mechanical reliability, and ease of processing. Here, we introduce a multifunctional, low‐outgassing liquid metal elastomer composite with a space‐grade silicone matrix (S‐LMEC) that combines the mechanical reliability of the silicone with enhanced thermal and electrical properties. Dispersed LM microdroplets enable a 2.3 higher breaking strain, an 11 increase in thermal conductivity, and a 9.6 increase in dielectric permittivity without hindering curing. Thermogravimetric analysis demonstrates that the embedded LM does not compromise the underlying thermal stability of the polymer matrix while active electronic testing indicates the S‐LMEC significantly lowers the steady‐state temperatures by promoting rapid heat dissipation. Furthermore, the material can be patterned into complex structures via direct ink write 3D printing. The outgassing evaluation of the S‐LMEC indicates a total mass loss (TML) of 1.00%. To demonstrate practical utility, the S‐LMEC was integrated into a wearable capacitive tactile glove for soft robotic skin applications. This materials platform expands the design space for space‐grade elastomers, enabling advancements in planetary exploration soft robotics and on‐demand electronics manufacturing.