| 摘要 |
PURPOSE:To produce a regenerated cellulose film having a well-controlled fractionation MW, by casting cellulose acetate dissolved in a solvent mixture of a poor solvent and a specified good solvent and removing acetic acid from the resulting film. CONSTITUTION:A poor solvent (e.g., formamide) is mixed with a good solvent mixture of acetylacetone and other good solvent (e.g., 1,4-dioxane) in a weight ratio of 1:0-1:9 in such a proportion as to give a weight ratio of 4:1-1:9 to obtain a solvent mixture. A soln. of 10-30wt% cellulose acetate in said solvent mixture is cast on a support having a mirror surface in a given casting thickness, and coagulated in an immersion bath to obtain a cellulose acetate film. The film is peeled from the support, wounded around a support such as a PP sheet, a PE sheet, etc., and acetic acid is removed. The film is washed with water and dried. |
