Fabricating Unidirectional Magnetic Papers Using Permanent Magnets to Align Magnetic Nanoparticle Covered Natural Cellulose Fibers
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چکیده
This paper reports a simple innovative method to align magnetic cellulose fibers by using a simple permanent magnet to fabricate unidirectional magnetic papers. Magnetic cellulose fibers were made by in situ synthesis of magnetite nanoparticles on alpha cellulose pulp extracted from American southern pine. Scanning electron microscope micrographs and energy dispersive X-ray spectroscopy maps indicated that magnetite nanoparticles completely covered the cellulose fibers. Suspensions of magnetic cellulose fibers were prepared at three levels of concentration (0.02, 0.04, and 0.08 g/L) and poured into the designed magnetic forming machine. Flow rate of suspension into the forming column was adjusted at 0, 0.3, 0.5, and 1 cm/s. The strength of the applied external magnetic field was the same in all cases and lower than 0.18 T. Orientation analysis indicated that the designed magnetic forming machine has a high performance to be used for aligning magnetic cellulose fibers and fabricating unidirectional magnetic cellulose papers. Observed anisotropic magnetic and mechanical properties confirmed the unidirectional structure.
منابع مشابه
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تاریخ انتشار 2011