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Wei Q, Li L, Deng Z, Wan G, Zhang Y, Du C, Su Y, Wang G. Scalable Fabrication of Nacre-Structured Graphene/Polytetrafluoroethylene Films for Outstanding EMI Shielding Under Extreme Environment. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2302082. [PMID: 37105765 DOI: 10.1002/smll.202302082] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 03/28/2023] [Indexed: 06/19/2023]
Abstract
In this work, inspired by the great advantage of the unique "brick-mortar" layered structure as electromagnetic interference (EMI) shielding materials, a multifunctional flexible graphene nanosheets (GNS)/polytetrafluoroethylene (PTFE) composite film with excellent EMI shielding effects, impressive Joule heating performance, and light-to-heat conversion efficiency is fabricated based on the self-emulsifying process of PTFE. Both PTFE microspheres and nanofibers are employed together for the first time as "sand and cement" to build unique nacre-structured EMI shielding materials. Such configuration can obviously enhance the adhesion of composites and improve their mechanical property for the application under extreme environment. Moreover, the simple and effective repetitive roll pressing method can be used for the scalable production in industrialization. The GNS/PTFE composite film shows a high EMI shielding effectiveness (SE) of 50.85 dB. Furthermore, it has a high thermal conductivity of 16.54 W (m K)-1 , good flexibility, and recyclable properties. The excellent fire-resistant and hydrophobic properties of GNS/PTFE film also ensure its reliability and safety in practical application. In conclusion, the GNS/PTFE film demonstrates the potential for industrial manufacturing, and outstanding EMI shielding performance with high stability and durability, which has a broad application prospect for electronic devices in practical extreme outdoor environments.
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Affiliation(s)
- Qiyi Wei
- School of Chemical Engineering and Technology, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, Hainan, 570228, China
- School of Materials Science and Engineering, Hainan University, Haikou, Hainan, 570228, China
| | - Liang Li
- School of Chemical Engineering and Technology, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, Hainan, 570228, China
- School of Materials Science and Engineering, Hainan University, Haikou, Hainan, 570228, China
| | - Zhen Deng
- School of Chemical Engineering and Technology, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, Hainan, 570228, China
- School of Materials Science and Engineering, Hainan University, Haikou, Hainan, 570228, China
| | - Gengping Wan
- School of Chemical Engineering and Technology, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, Hainan, 570228, China
- School of Materials Science and Engineering, Hainan University, Haikou, Hainan, 570228, China
| | - Ying Zhang
- School of Chemical Engineering and Technology, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, Hainan, 570228, China
- School of Materials Science and Engineering, Hainan University, Haikou, Hainan, 570228, China
| | - Changlong Du
- School of Chemical Engineering and Technology, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, Hainan, 570228, China
- School of Materials Science and Engineering, Hainan University, Haikou, Hainan, 570228, China
| | - Yanran Su
- School of Chemical Engineering and Technology, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, Hainan, 570228, China
- School of Materials Science and Engineering, Hainan University, Haikou, Hainan, 570228, China
| | - Guizhen Wang
- School of Chemical Engineering and Technology, State Key Laboratory of Marine Resource Utilization in South China Sea, Hainan University, Haikou, Hainan, 570228, China
- School of Materials Science and Engineering, Hainan University, Haikou, Hainan, 570228, China
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Multilayered Composites with Carbon Nanotubes for Electromagnetic Shielding Application. Polymers (Basel) 2023; 15:polym15041053. [PMID: 36850335 PMCID: PMC9963311 DOI: 10.3390/polym15041053] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/20/2023] [Accepted: 02/17/2023] [Indexed: 02/22/2023] Open
Abstract
Bulk polylactic acid (PLA)/multiwall carbon nanotube (MWCNT) composites were prepared and investigated in wide frequency ranges (20 Hz-1 MHz and 24-40 GHz). It was determined that the percolation threshold in bulk PLA/MWCNT composites is close to 0.2 vol.% MWCNT. However, the best microwave dielectric properties and absorption were observed in composites with 3.0-5.0 vol.% MWCNT. Therefore, for future investigations, we selected layered (laminate) polymeric structures with gradual changes in MWCNT concentration from 0.2 to 8.0 vol.% MWCNT. Two approaches to laminate structure designs were examined and compared: a five-layer composite and a nine-layer composite that included four pure PLA middle layers. The addition of MWCNT enhanced the elastic modulus by up to 1.4-fold and tensile strength by up to 1.2-fold, with the best performance achieved at 5.0 vol.% loading. High microwave shielding was observed for these layered PLA/MWCNT structures with a gradient change in MWCNT concentration (up to 26 dB in both transmission and absorption coefficients) in the broad frequency range (from 24 to 40 GHz). Obtained structures are highly anisotropic, and the absorption coefficient is 2-5 dB higher in the direction of MWCNT concentration increase; however, the transmission coefficient is the same in both directions. The properties of microwave absorption are mainly unaffected by the additional polymeric layers. The absorption of the layered structure is greater than the absorption of single-layer composites with an optimal MWCNT concentration of the same thickness. The proposed laminate structure design is promising in the field of efficient electromagnetic shielding.
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