Rupture stress of liquid metal nanoparticles and their applications in stretchable conductors and dielectrics

Abstract

Abstract Few works had systematically investigated the relationship between the rupture stress of the oxide shell and the diameter of liquid metal nanoparticles (LMNPs). Here, we fabricated a series of elastomer/LMNPs composites, which were based on various polyurethanes with different shore hardness and LMNPs with different diameters, to systematically study the rupture stress of LMNPs. We established a reliable and guidable relationship between the stress–strain curves of elastomers with different shore hardness and rupture stress of LMNPs with various diameters by both experiments and numerical calculations. Based on this guidance, we can facilely prepare stretchable conductors with remarkable stretchability and conductivity (i.e., 24,130 S · cm−1 at 500% strain) and stretchable dielectrics with excellent stretchability and permittivity (i.e., dielectric constant of 76.8 with 580% strain) through controlling the shore hardness of elastomers and diameter of LMNPs. This work will facilitate the systematic study of LMNPs and expand their use in stretchable electronics.