Enhancing vertical thermal conductivity of carbon fiber reinforced polymer composites using cauliflower-shaped copper particles

Abstract

Carbon fiber reinforced polymer (CFRP) composites are lightweight and mechanically robust, and therefore have received considerable attention with a wide range of applications from the aerospace to automotive industries. However, their low vertical thermal conductivity seriously limits the potential applicability of high-performance CFRPs in metal replacement. Herein, we propose a simple and effective, scalable strategy to fabricate thermally conductive and mechanically robust CFRP composites on the basis of formation of vertical heat transfer pathways using pressure-assisted thermal migration of cauliflower-shaped dendritic copper particles. A new type of CFRP composite was achieved by facile layer-by-layer coating of prepregs with dendritic coppers and subsequent pressure-assisted thermal processing under elevated temperature. The cauliflower-shaped dendritic copper particles efficiently infiltrated into the CFRP matrix and thereby provided an effective heat transfer pathway, resulting in a CFRP composite with an excellent vertical thermal conductivity of 2.321 W m−1 K−1, which is 155% higher than that of pristine CFRP. Moreover, the proposed CFRP composite afforded a high thermal diffusivity of 1.125 × 10−6 m2 s−1 and a low specific heat capacity of 1.267 J g−1 K−1, as well as an excellent flexural strength of about 2.4 GPa.