| 摘要 |
PURPOSE:A sheet of acrylonitril semipermeable membrane is prepared and fabricated into tubular form, whereby the sheet is seamed by using adhesive comprising polymer solution of the same component as the membrane or similar one, to thereby provide adhesively processed membrane without losing its original function. CONSTITUTION:Solution 2 of acrylonitril polymer in solvent such as DMF is cast on woven or nonwoven web 1, wet coagulated in nonsolvent solution 3 such as aqueous DMF solution, heat treated by hot water 4, dried and formed into a flat sheet 6. The flat sheet 6 passes through a guide roll 8 to a cylinder guide 9. Adhesive polymer solution 12 is supplied from feeding hole 10 onto both edges of the sheet 6. By means of a guide bar 14 and a cone type guide 13, the sheet 6 is formed into tubular form, the polymer adhesive is coagulated using the same solution 15 as before, and the formed tube is pulled through rolls 16 and 17 to be wound 18. It is essential to this process that the polymer solution 12 should have the same or similar composition as the flat sheet 6. |
