Resilient thermal interface materials with high through-plane thermal conductivity based on consistent construction of carbon fibers arrays

Abstract

Thermal management issues in electronics force thermal interface materials (TIMs) possessing both high thermal conductivity and excellent resilience, but simultaneously achieving these properties in TIMs remains challenging. In this paper, TIMs with both high thermal conductivity and mechanical properties are prepared by vertically aligning long mesophase pitch-based carbon fibers (CFs) in a simple lay-up method. The vertically aligned long CFs can not only minimize the thermal conductivity channels and maximize the number of the channels, but also provide structural support for the soft silicone rubber (SR) matrix, thus enabling TIMs to obtain both excellent thermal conductivity and mechanical properties. As a result, the prepared composite with a CFs content of 70 wt% possesses through-plane thermal conductivity up to 28.4 W m⁻¹ K⁻¹. In addition, the composite exhibits impressive mechanical properties, including a low Shore 00 hardness of 61, a high compressibility of 63.8 %, and superior rebound rate of 82 % under 45 psi pressure. With this high filler ratio, the stunning results highlight the potential of the carbon fiber arrays-filled composite for the advanced thermal management applications, which provides a reference scheme for further fabrication of high-performance resilient TIMs.