Core-shell Co-C@CNT engineered to enable concurrent thermal conductivity and microwave absorption for Poly(4, 4′-dihydroxybiphenyl isophthalate)
Xiao Zhong, Junwei Gu
Abstract
As electronic devices trend toward miniaturization and higher performance, effective heat dissipation and electromagnetic interference suppression have become critical challenges. The development of thermally conductive/microwave absorption polymer composites is urgently required. In this work, carbon nanotube (CNT) is grown in-situ on Co-C surface through pyrolysis of thermally robust, large-particle zeolitic imidazolate framework-67 (ZIF-67) and melamine (MF). The obtained core-shell Co-C@CNT is blended with a self-synthesized side-chain poly(4, 4′-dihydroxybiphenyl isophthalate) (S-PDI) to prepare Co-C@CNT/S-PDI composites using “solution coating-stacking-hot pressing” process. When the MF:ZIF-67 mass ratio is 1.5:1, an optimal core-shell morphology and the highest thermal conductivity of Co-C@CNT are achieved. 25 wt% Co-C@CNT/S-PDI composites exhibit thermal conductivity of 0.84 W/(m·K), which is 133.3% higher than that of S-PDI (0.36 W/(m·K)). Moreover, corresponding minimum reflection loss, elasticity modulus and heat resistance index reach −53.8 dB (8.08 GHz), 5.3 GPa and 185.0 °C, respectively.