| 摘要 |
<p>The invention is directed to a procedure for manufacturing cellulose carbamate by reacting isocyanic acid and cellulose at elevated temperature. In the procedure, cellulose, to which biuret or a mixture of biuret and urea has been admixed or absorbed, is heated at a temperature over 170 DEG C. for a sufficient time to produce a quantity of isocyanic acid sufficient for formation of the cellulose carbamate and for accomplishing the reaction between cellulose and isocyanic acid. The heating is accomplished at 170 DEG -250 DEG C., preferably at about 220 DEG C. The biuret quantity is 3-50% by weight of the cellulose weight and the urea quantity is 0-95% by weight of the cellulose weight.</p> |
