| 摘要 |
PURPOSE:To obtain a chemically stable amphoteric ion exchanger by a method wherein chitin stock material is crosslinked, carboxyalkylated and deacetylated to give crosslinked carboxyalkylchitosan having amphoteric ion exchanging property. CONSTITUTION:Chitin obtained from a crustacean shell or the like of crab, shrimp or the like is subjected to the micelle swelling and, thereafter, crosslinked by a crosslinking agent and, moreover, subjected to the carboxyalkylation to obtain crosslinked carboxyalkylchitin. This compound is moreover deacetylated to prepare crosslinked carboxyalkylchitosan. This crosslinked carboxyalkylchitosan has a crosslinking degree of 0.01-0.3, a carboxyalkyl substitution degree of 0.1-0.9, a deacetylation degree of 0.1-1, an infrared characteristic absorption at 1680-1720cm<-1> and 1500-1530cm<-1> and, when is reacted with iodine in the presence of sulfuric acid, develops purple color and is in soluble in an aqueous solution of an acidic, an alkaline, or a neutral salt, has amphoteric ion exchanging property and is useful in the desalting of sugar, the preparation of a permeable material or the like. |
