Flexible Thermal Conductive Electromagnetic Interference Shielding of Liquid Metal‐Based Silicon Polymer Composites: Strain Level Effect

ABSTRACT This research successfully created flexible liquid metal (LM) based silicon polymer composites with exceptional thermal conductivity and electromagnetic interference (EMI) shielding. The composite achieved significant improvements in mechanical strength, flexibility, EMI shielding effectiveness, and thermal conductivity, which are dependent on the addition of LM content and levels of strain. The composites exhibited an EMI shielding effectiveness (SE) of 63.19 dB in the X‐band frequency range under 300% strain. This performance is attributed to the deformation of LM particles, which form interconnected pathways that efficiently block electromagnetic interference. The attenuation of electromagnetic waves within the composite is explained by a multireflection mechanism. In addition, the composite demonstrated a thermal conductivity of 3.46 W/mK under 300% strain, facilitated by the thermally conductive networks formed by LM. The composites demonstrated improved heat dissipation compared to the commercial thermal pad. These combined properties establish the composites as a promising direction for the development of advanced materials tailored for practical use in emerging technologies, including smart 5G devices, telecommunication systems, and radar equipment.