RGO-Coated Polyurethane Foam/Segmented Polyurethane Composites as Solid-Solid Phase Change Thermal Interface Material.

Cong Zhang,An Li,Zhe Shi,Yang-Fei Zhang

doi:10.3390/polym12123004

Abstract

Thermal interface material (TIM) is crucial for heat transfer from a heat source to a heat sink. A high-performance thermal interface material with solid–solid phase change properties was prepared to improve both thermal conductivity and interfacial wettability by using reduced graphene oxide (rGO)-coated polyurethane (PU) foam as a filler, and segmented polyurethane (SPU) as a matrix. The rGO-coated foam (rGOF) was fabricated by a self-assembling method and the SPU was synthesized by an in situ polymerization method. The pure SPU and rGOF/SPU composite exhibited obvious solid–solid phase change properties with proper phase change temperature, high latent heat, good wettability, and no leakage. It was found that the SPU had better heat transfer performance than the PU without phase change properties in a practical application as a TIM, while the thermal conductivity of the rGOF/SPU composite was 63% higher than that of the pure SPU at an ultra-low rGO content of 0.8 wt.%, showing great potential for thermal management.

Highlights

Thermal management is crucial for the electronic industries, and strongly affects the performance, reliability, and lifetime of devices with high integration and power density [1]
The internal morphology of the PU foam, rGO-coated foam (rGOF), and rGOF/segmented polyurethane (SPU) composite were observed by the scanning electron microscope (SEM)
The reduced graphene oxide (rGO)-coated PU foam-filled SPU composite was successfully prepared as a thermal interface material (TIM) with solid–solid

Summary

Introduction

Thermal management is crucial for the electronic industries, and strongly affects the performance, reliability, and lifetime of devices with high integration and power density [1]. Because of the surface roughness of electronic chips and heat sinks, the real contact area between them is less than 10% [2], seriously affecting the thermal contact resistance, causing heat concentration on the chip surface and thermal induced failures. A thermal interface material (TIM), mainly composed of polymer matrixes and thermal conductive fillers such as metals, ceramics, carbon materials, and hybrid fillers, can be applied between the heat source and the heat sink to fill the voids and grooves caused by imperfections of mating surfaces, minimizing the thermal contact resistance [3,4]. With the advantages of high thermal conductivity and a lightweight nature, graphene composites have attracted great attention in thermal management applications [8,9,10]. Many methods have been developed to prepare 3D interconnected structures, including self-assembly, freeze drying, and chemical vapor deposition [13,14,15,16,17,18]

Methods

Results

Conclusion