The influence of the transparent layer thickness on the absorption capacity of epoxy/carbon nanotube buckypaper at X-band

Autor(es)

dos Reis, Felipe Carlos ^[1] ; Rezende, Mirabel Cerqueira ^[1] ; Ribeiro, Bruno ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Paulo UNIFESP, Inst Ciencia & Tecnol, Sao Jose Dos Campos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Applied Polymer Science; v. 138, n. 47 JUL 2021.
• Citações Web of Science: 0

Resumo

Carbon nanotube films (BPs) as EMI shielding materials can be applied in electronic and communication devices due to their high electrical conductivity. Sandwich structures can offer excellent shielding effectiveness by introducing a wave-transmitting layer between conductive films. However, the optimization of the structure demands a deep investigation and plays a crucial role in the final shielding properties of the composites. In this work, BPs are incorporated into epoxy substrates with variable thicknesses (1-6 mm) to fabricate epoxy/BP sandwich structures. The morphology of the CNT films is analyzed by SEM, and the electrical conductivity of all prepared samples is measured by 4-point method. The electromagnetic tests are carried out in the X-band (8.2-12.4 GHz) through the scattering parameters. SEM images reveal a porous structure without visible agglomeration. The electrical conductivity of the BP reaches up to 996 S/m, whereas the values for epoxy/BP composites varies in the range of 8.51-3.13 S/m (1 to 3 mm). BP total shielding efficiency (SET) is approximately 14 dB along the X-band spectrum, with similar contributions of reflection and absorption losses. While, the composites show mainly absorbing behavior, especially in the thicker samples, with more significant SET values (23.4 dB-6 mm). (AU)

• Processo FAPESP: 17/04740-0 - Obtenção e caracterização de compósitos nanoestruturados multifuncionais baseados em laminado de fibra de vidro/resina epóxi/buckypapers de nanotubos de carbono
• Beneficiário: Bruno Ribeiro
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 19/01623-8 - Obtenção e caracterização elétrica e eletromagnética de compósitos de resina epóxi com buckypapers de nanotubos de carbono de paredes múltiplas
• Beneficiário: Felipe Carlos dos Reis
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica