{"title":"Nacre-inspired flexible and thermally conductive phase change composites with parallelly aligned boron nitride nanosheets for advanced electronics thermal management","authors":"Zi-jie Huang, Rui-qing Wang, Wan-jun Jiang, Yu-long Liu, Ting-yu Zhu, De-xiang Sun, Jing-hui Yang, Xiao-dong Qi, Yong Wang","doi":"10.1016/j.compscitech.2024.110736","DOIUrl":null,"url":null,"abstract":"<div><p>Phase change materials (PCMs) are widely applied in passive thermal management and energy storage fields because of their large latent heat capability near phase transition points. However, molten leakage, inherent rigidity, and low thermal conductivity limit the thermal management applications of PCMs. In this work, a scalable doctor-blading technique was developed to prepare anti-leakage, flexible, and highly thermally conductive PCM composites. Paraffin wax (PW) works as the thermal energy storage unit, polydimethylsiloxane (PDMS) encapsulates the molten PW and imparts the composites with flexibility, and 1-Butyl-3-methylimidazolium Hexafluorophosphate (BMIMPF6)-modified boron nitride nanosheets (BPs) ensure high thermal conductivity. BPs were firstly achieved from bulk boron nitride (BN) powders and BMIMPF6 ionic liquid (IL) by the one-step ball milling process, then high-oriented alignment of BPs in PDMS/PW matrix was obtained by the strong shearing forces along the blade-casting direction. Owing to the high quality of BPs and interconnected structure of BPs network, the composites possessed high in-plane thermal conductivity of 2.87 W·m<sup>−</sup><sup>1</sup>·K<sup>−</sup><sup>1</sup> at 15 wt% BPs, exhibiting a remarkable enhancement of 1494 % compared with PDMS/PW. The flexible composites showed effective heat dissipation performance by reducing the working temperature of smartphones over 11 °C. Finite element analysis demonstrated that the parallel alignment of BPs network and the thermal energy buffering of PW were crucial for improving the thermal management capability. Furthermore, the PDMS/PW/BP composites exhibited excellent flame-retardant and electrically insulating properties. This work provides a feasible method to prepare high-performance PCM composites, which show great application prospects in the thermal management of electronic devices.</p></div>","PeriodicalId":283,"journal":{"name":"Composites Science and Technology","volume":null,"pages":null},"PeriodicalIF":8.3000,"publicationDate":"2024-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Composites Science and Technology","FirstCategoryId":"88","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0266353824003063","RegionNum":1,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"MATERIALS SCIENCE, COMPOSITES","Score":null,"Total":0}
引用次数: 0
Abstract
Phase change materials (PCMs) are widely applied in passive thermal management and energy storage fields because of their large latent heat capability near phase transition points. However, molten leakage, inherent rigidity, and low thermal conductivity limit the thermal management applications of PCMs. In this work, a scalable doctor-blading technique was developed to prepare anti-leakage, flexible, and highly thermally conductive PCM composites. Paraffin wax (PW) works as the thermal energy storage unit, polydimethylsiloxane (PDMS) encapsulates the molten PW and imparts the composites with flexibility, and 1-Butyl-3-methylimidazolium Hexafluorophosphate (BMIMPF6)-modified boron nitride nanosheets (BPs) ensure high thermal conductivity. BPs were firstly achieved from bulk boron nitride (BN) powders and BMIMPF6 ionic liquid (IL) by the one-step ball milling process, then high-oriented alignment of BPs in PDMS/PW matrix was obtained by the strong shearing forces along the blade-casting direction. Owing to the high quality of BPs and interconnected structure of BPs network, the composites possessed high in-plane thermal conductivity of 2.87 W·m−1·K−1 at 15 wt% BPs, exhibiting a remarkable enhancement of 1494 % compared with PDMS/PW. The flexible composites showed effective heat dissipation performance by reducing the working temperature of smartphones over 11 °C. Finite element analysis demonstrated that the parallel alignment of BPs network and the thermal energy buffering of PW were crucial for improving the thermal management capability. Furthermore, the PDMS/PW/BP composites exhibited excellent flame-retardant and electrically insulating properties. This work provides a feasible method to prepare high-performance PCM composites, which show great application prospects in the thermal management of electronic devices.
期刊介绍:
Composites Science and Technology publishes refereed original articles on the fundamental and applied science of engineering composites. The focus of this journal is on polymeric matrix composites with reinforcements/fillers ranging from nano- to macro-scale. CSTE encourages manuscripts reporting unique, innovative contributions to the physics, chemistry, materials science and applied mechanics aspects of advanced composites.
Besides traditional fiber reinforced composites, novel composites with significant potential for engineering applications are encouraged.