Enhancing thermal conductivity and electromagnetic shielding performance of Ni-CNT/Al2O3/PVDF composite film with a multi-layered structure

• Published in: Composites science and technology Vol. 251; p. 110589
• Main Authors: Li, Xiaolei, Ma, Chuanguo, Chi, Hongtao, Song, Muyuan, Lu, Shaoning, Dai, Peibang
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 26.05.2024
• Subjects: Electromagnetic interference shielding (EMI); Microstructural analysis; Polymer-matrix composites (PMCs); Thermal properties; Thin films; Thin films; Thermal properties; Polymer-matrix composites (PMCs); Electromagnetic interference shielding (EMI); Microstructural analysis
• ISSN: 0266-3538; 1879-1050
• DOI: 10.1016/j.compscitech.2024.110589

To develop thermal interface materials with both high thermal conductivity and electromagnetic interference shielding, the polyvinylidene fluoride (PVDF) composite film was prepared by electrospinning and hot-pressing, using strategies of multi-layered structure and two fillers synergy of nickel modified carbon nanotube (Ni-CNT) and Al2O3 microspheres. The composite film consisted of a Ni-CNT filled PVDF electrospun fiber film as the top and bottom surface layers, and a PVDF electrospun fiber film electrostatically adsorbing Al2O3 microspheres and surface-sprayed with Ni-CNT as the middle layer. At a 20 wt% Ni-CNT in the surface layers and a 16.7 wt% Al2O3 and 5 wt% Ni-CNT in the middle layer, the composite film with a thickness of 0.1 mm exhibited optimal performances with electromagnetic wave shielding efficiency of 65 dB in the frequency range of 8.2–12.4 GHz, with 86% of the electromagnetic waves being absorbed. At the same time, the composite film had a high in-plane thermal conductivity of 4.02 W m−1 K−1, while maintaining a tensile strength of 25 MPa and flexibility. Using strategies of multi-layered structure and two fillers synergy of nickel modified carbon nanotube (Ni-CNT) and Al2O3 microspheres, the as-prepared composite film with a thickness of 0.1 mm exhibited total electromagnetic wave shielding efficiency (SET) of 65 dB and electromagnetic wave absorption efficiency (SEA) of 56 dB in the frequency range of 8.2–12.4 GHz, and a high in-plane thermal conductivity of 4.02 W m−1 K−1. [Display omitted]