The Polymer Society of Korea

Abstract

Thermal management in flexible electronics requires thermal interface materials (TIMs) that combine high thermal conductivity with mechanical compliance, yet these targets often conflict because high filler loading can reduce softness and conformability. Here, we apply dielectrophoresis (DEP) to directionally align metallic filler particles within a polymer matrix, forming field guided thermal pathways for directional heat transport. With a filler volume fraction of φ = 20%, the DEP processed composites reach anisotropic thermal conductivity values up to 0.6 W/m·K. Mechanical testing shows that the aligned TIMs maintain elasticity and flexibility, accommodating deformation without macroscopic loss of integrity. Overall, DEP enabled filler alignment offers a simple route to tune anisotropic heat dissipation in soft polymer composites, providing a practical design strategy for next generation flexible TIM applications while preserving compliance.