Abstract Thermal contact resistance is a key bottleneck to restrict the rapid heat dissipation of electronic device. The wetting between two contact surfaces is one of the most important factors affecting the thermal contact resistance. Phase change thermal interface material can transform from solid state to molten state by heat inducing, which is an efficient way to reduce the thermal contact resistance. In this work, a novel form stable phase change thermal interface material of graphene/olefin block copolymer/paraffin filled with graphene (≤4.0 wt%) was designed. Furthermore, the influence of temperature and pressure on thermal contact resistance were studied, and the dominant position of thermal contact resistance and RTIMs in total thermal resistance was analyzed systematically. The results exhibit that thermal contact resistance decreases sharply from 8–20 Kcm2/W to 0.1–0.2 Kcm2/W for the temperature increases from 37 °C to 45 °C (50 Psi), with a drop of up to two orders of magnitude. This is because the wettability of the two contact surfaces is greatly improved by changing solid–liquid contact to solid–liquid contact. In addition, the thermal contact resistance decreases slightly with the increase of pressure (10–50 Psi, 48 °C). A small amount of graphene can significantly enhance the thermal conductivity of graphene/olefin block copolymer/paraffin, but the effect on thermal contact resistance is relatively weak. Moreover, critical thickness is proposed to quantitatively evaluate the dominant position of thermal contact resistance or RTIMs in total thermal resistance. It facilitates the quantitative analysis and optimization of thermal resistance in practical application.

中文翻译：

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石墨烯/烯烃嵌段共聚物/石蜡形成稳定相变热界面材料的热接触电阻显着降低

摘要 接触热阻是制约电子器件快速散热的关键瓶颈。两个接触面之间的润湿是影响接触热阻的最重要因素之一。相变热界面材料可以通过热诱导从固态转变为熔融态，这是降低接触热阻的有效方法。在这项工作中，设计了一种石墨烯/烯烃嵌段共聚物/石蜡填充石墨烯（≤4.0 wt%）的新型稳定相变热界面材料。进一步研究了温度和压力对接触热阻的影响，系统分析了接触热阻和RTIMs在总热阻中的主导地位。结果表明，随着温度从 37 °C 升高到 45 °C (50 Psi)，接触热阻从 8–20 Kcm2/W 急剧下降到 0.1–0.2 Kcm2/W，下降幅度高达两个数量级. 这是因为通过将固液接触改为固液接触，大大提高了两个接触面的润湿性。此外，随着压力的增加（10-50 Psi，48°C），接触热阻略有下降。少量石墨烯可以显着提高石墨烯/烯烃嵌段共聚物/石蜡的热导率，但对接触热阻的影响相对较弱。此外，提出了临界厚度来定量评估热接触电阻或 RTIMs 在总热阻中的主导地位。