Effects of sample thickness and fiber aspect ratio on EMI shielding effectiveness of carbon fiber filled polychloroprene composites in the X-band frequency range

The electromagnetic interference shielding effectiveness and return loss of short carbon-filled polychloroprene rubber composites of varying sample thickness and fiber aspect ratio were studied in the frequency range of 8 to 12 GHz (X-band). It was observed that composites prepared by the cement-mixed method with high fiber aspect ratio (L/D=100) show higher shielding effectiveness and lower return loss than the composites prepared by the mill-mixed method with low fiber aspect ratio (L/D=25). This indicates that loss due to absorption increases with increasing fiber aspect ratio. A similar effect has also been observed with increasing sample thickness