Dielectric properties of microwave absorbing sheets produced with silicone and polyaniline

Abstract

The aim of this study was to produce sheets of microwave absorbing materials using conductive polyaniline dispersed in a silicone rubber matrix and to characterize the electromagnetic properties (absorption, transmission and reflection of electromagnetic energy; and electric permittivity and magnetic permeability) of these sheets in the X-band (8 -12 GHz). Two sheets were produced: one 2.80 mm thick and the other 4.39 mm thick. The thinner sheet absorbed incident microwave energy more efficiently, attenuating up to 88% of the incident electromagnetic energy. Also, calculations were performed in order to determine the electromagnetic parameters that optimize the absorbent properties of these sheets. These calculations showed that these materials can be combined and altered to produce absorbing materials with a wide range of absorbing characteristics.

Estudo da aplicação da poli(o-metoxianilina) e de seus compósitos com negro de fumo no processamento de absorvedores de micro-ondas

“…Dentre os aditivos mais comumente utilizados no processamento desses materiais destacam-se as ferritas, a ferro carbonila, o negro de fumo e os polímeros condutores [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18] . Considerando-se os polímeros condutores, vale ressaltar a sua crescente importância na área de MARE, em função de suas interessantes propriedades físicas (eletrônicas), estabilidade química, facilidade de síntese, relativa facilidade de processamento e, principalmente, menor massa específica em relação às ferritas e à ferro carbonila [2,[9][10][11][12][13][14][15][16][17][18] . Os polímeros condutores têm despertado crescentes interesses científicos e tecnológicos nos últimos anos, devido às suas propriedades, em particular, sua condutividade elétrica.…”

Sulfonated polyaniline: influence of sulfonation routes on its thermal and structural characteristics

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Polymer matrix composites as broadband radar absorbing structures for stealth aircrafts

“…The polymer used for preparing nano coating was polyurethane and the total thickness of the composite was 2. 2 mm with a specific mass of 1.6 g/cm 3 . The possibility of using Plasma along with graphene for RAS has been reported recently by Mahdi et al .…”