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Composite absorbers based on conducting fabrics possessing moderate conductivity and dielectric/magnetic properties were prepared by in situ incorporation of nanoparticles of BaTiO 3 (15−25 nm) or Fe 3 O 4 (25−40 nm) within coated poly(aniline) (PANI) matrix. The X-ray diffraction patterns and transmission electron microscopy images confirmed the formation of PANI coating and incorporation of BaTiO 3 or Fe 3 O 4 nanoparticles. Scanning electron microscopy images show formation of thick and uniform coating of PANI over individual fibers and in interweave regions. The dielectric studies show that incorporation of BaTiO 3 lead to enhancement of dielectric properties of PANI whereas magnetization measurements revealed that incorporation of Fe 3 O 4 resulted in noticeable improvement in magnetic properties with saturation magnetization of 17.9 emu/g. The Ku-band (12.4−18.0 GHz) shielding studies revealed that pure PANI-coated fabric show total shielding effectiveness (SE T ) of −15.3 dB which enhanced to −16.8 and −19.4 dB after incorporation of BaTiO 3 and Fe 3 O 4 nanoparticles respectively. Such an improvement can be attributed to the better matching of input impedance, reduction of skin depth, and additional dielectric/magnetic losses. The high value of absorption-dominated SE T (i.e., 97−99% attenuation) and specific shielding effectiveness value of 17−20 dB cm 3 /g demonstrate the potential of these fabrics as promising microwave-shielding material. In addition, these fabrics also display good antistatic response with static charge decay time of only 0.11 s.

Sugarcane bagasse (SCB) is abundantly available agro-waste world-wide and has been used in different applications and its utilization as a source of cellulose attracting attention in the area of biomedical and other applications. The present study investigates the surface morphology, topography, structural, elemental and thermal properties of cellulose nanocrystals (CNCs) extracted by acid-hydrolysis from sugarcane bagasse as agro-waste. Morphological (field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), transmission electron microscopy (TEM)), structural (fourier transformed infrared (FTIR) spectroscopy, X-ray diffraction (XRD)), elemental analysis (energy dispersive x-ray diffraction (EDX)) and thermal characterization (TG-DTG-DTA) of CNCs was carried out. Morphological characterization clearly showed the formation of rodshaped CNCs having size in the range of 250-480 nm (length) and 20-60 nm (diameter). Elemental analysis (EDX) showed 0.72 wt% sulfur impurity in CNCs along with other main components. X-ray diffraction and thermal analysis revealed that CNCs have higher crystallinity (72.5%) than that of chemically purified cellulose (CPC) (63.5%) but have lower thermal stability. These lab extracted CNCs supposed to have a high potential as nanoreinforcement into bionanocomposite for biomedical and other value-added products in industrial applications.

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