Production manner null of I die seruro - sutoriasete -

摘要

PURPOSE:To facilitate the formation of type I cellulose triacetate, by evaporating a solution of cellulose triacetate in a phenolic solvent to dryness or coagulation. CONSTITUTION:A solution of cellulose triacetate in a phenolic liquid solvent is evaporated to dryness or coagulation. Said cellulose triacetate is one having a weight-average degree of polymerization =10 and derived by acetylating at least 90% of the hydroxyl groups of the corresponding cellulose. Examples of said phenolic liquids include those of an M.P. =60 deg.C, such as phenol, cresols (o-, m- and p-) and 2,3-dimethylphenol. To evaporate said cellulose triacetate solution to dryness or coagulation, it is suitable to distill off the solvent from the solution in vacuo.