This paper reviews studies on dissolution, derivatization, and nanomaterial processing of chitin using an ionic liquid as useful media. Because chitin is the second most abundant polysaccharide on the earth after cell...This paper reviews studies on dissolution, derivatization, and nanomaterial processing of chitin using an ionic liquid as useful media. Because chitin is the second most abundant polysaccharide on the earth after cellulose, there is major interest in conversion of native chitin resources into various useful materials after proper dissolution in suitable solvents. For the derivatization and nanomaterial processing of chitin, the author has been focusing on ionic liquids because which have been found to be used as good solvents for cellulose in a past decade. The author found that an ionic liquid, 1-allyl-3-methylimidazolium bromide (AMIMBr), dissolved chitin in concentrations up to 4.8 wt% and mixtures of the higher amounts of chitin with AMIMBr gave ion gels. Acetylation, the simplest derivatization, of chitin using acetic anhydride was achieved in the AMIMBr solvent under mild conditions. Furthermore, the chitin nanofibers were fabricated by regeneration technique from the chitin ion gel with AMIMBr using methanol. Moreover, filtration of the chitin nanofiber dispersion with methanol was carried out to give a chitin nanofiber film. The chitin nanofiber-poly(vinyl alcohol) composite film was also prepared from the ion gel by co-regeneration method.展开更多
Reduction of methylene blue (MB) occurred by photo irradiation at 280 - 370 nm wavelengths to a solution of MB in an ionic liquid, 1-butyl-3-methylimidazolium chloride (BMIMCl), which was confirmed by color change and...Reduction of methylene blue (MB) occurred by photo irradiation at 280 - 370 nm wavelengths to a solution of MB in an ionic liquid, 1-butyl-3-methylimidazolium chloride (BMIMCl), which was confirmed by color change and UV-Vis measurement of the solution. Furthermore, the reduced MB was oxidized again by standing the solution under the conditions of light shielding at 50?C. The fluorescence spectra of the solution excited at 350 nm suggested that the photo-induced reduction probably took place via electron-transfer from BMIMCl to MB.展开更多
文摘This paper reviews studies on dissolution, derivatization, and nanomaterial processing of chitin using an ionic liquid as useful media. Because chitin is the second most abundant polysaccharide on the earth after cellulose, there is major interest in conversion of native chitin resources into various useful materials after proper dissolution in suitable solvents. For the derivatization and nanomaterial processing of chitin, the author has been focusing on ionic liquids because which have been found to be used as good solvents for cellulose in a past decade. The author found that an ionic liquid, 1-allyl-3-methylimidazolium bromide (AMIMBr), dissolved chitin in concentrations up to 4.8 wt% and mixtures of the higher amounts of chitin with AMIMBr gave ion gels. Acetylation, the simplest derivatization, of chitin using acetic anhydride was achieved in the AMIMBr solvent under mild conditions. Furthermore, the chitin nanofibers were fabricated by regeneration technique from the chitin ion gel with AMIMBr using methanol. Moreover, filtration of the chitin nanofiber dispersion with methanol was carried out to give a chitin nanofiber film. The chitin nanofiber-poly(vinyl alcohol) composite film was also prepared from the ion gel by co-regeneration method.
文摘Reduction of methylene blue (MB) occurred by photo irradiation at 280 - 370 nm wavelengths to a solution of MB in an ionic liquid, 1-butyl-3-methylimidazolium chloride (BMIMCl), which was confirmed by color change and UV-Vis measurement of the solution. Furthermore, the reduced MB was oxidized again by standing the solution under the conditions of light shielding at 50?C. The fluorescence spectra of the solution excited at 350 nm suggested that the photo-induced reduction probably took place via electron-transfer from BMIMCl to MB.