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Abstract
This work aims at the fabrication of NBR composites for microwave shielding. These composites are based on nano sized carbon black (CB) and nano-scale lithium ferrites (LF) as electrically conductive and ferromagnetic fillers respectively. NBR has been chosen as the rubbery matrix due to its thermal resistance and polar nature. Moreover, NBR is compatible with most fillers and additives and has a great capacity to be filled with high filler loadings. Li0.5Fe2.5O4 has been synthesized by citrate nitrate autocombustion method and was characterized using X- ray diffraction (XRD). The average crystallite size of LF was found to be 38 nm as calculated from scherrer’s equation. Two series have been fabricated by incorporating CB or LF in NBR matrix. The loading level of either CB or LF ranges from 10 - 100 phr in an increment of 10 phr. Thus 20 samples have been prepared, ten CB loaded NBR composites nominated as CB10, CB20, CB100; and ten LF loaded NBR composites nominated as LF10, LF20, LF100. A preliminary microstructural characterization of the prepared composites has been done using XRD. The addition of LF was found to greatly improve the crystallinity of NBR but CB could not do so