کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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5183208 | 1381011 | 2011 | 7 صفحه PDF | دانلود رایگان |
Natural cellulosic ramie fiber was acetylated using supercritical carbon dioxide (sc-CO2) as a reaction medium. The structure and properties of the acetylated fibers were investigated using infrared spectroscopy, scanning electron microscopy, X-ray diffraction (including synchrotron microbeam X-ray diffraction), nano-Raman scattering, and a tensile test. The acetylation reaction proceeded without using an organic solvent, and it reached to the core part of the fiber within a short period while maintaining the fiber morphology. The crystallites of cellulose triacetate II and cellulose coexist in the fiber. The acetylated fiber with an average degree of substitution of 1.9 showed high modulus (34.5Â GPa) and high strength (763Â MPa), which are the highest values for cellulose diacetate so far reported to date.
Journal: Polymer - Volume 52, Issue 3, 3 February 2011, Pages 830-836