| 摘要 |
<p>1,227,280. Semipermeable polyamide films. RHONE - POULENC S.A. 1 Oct., 1969 [2 Oct., 1968], No. 48365/69. Heading B5B. [Also in Divisions B1 and C3] Semi-permeable membranes are made from polyamides containing a plurality of units of the formula alone or in combination with units where X and Y are divalent organic radicals and R is H, C 1-4 alkyl, 5 or 6 member cycloalkyl, phenyl, C 1-4 alkylphenyl or aralkyl or 2 R's in -NR-X-NR- may be joined to complete a heterocyclic ring. Such polyamides are described and claimed in Specification 1,208,357. The polymer is formed with the NH 2 group protector and its subsequent liberation may be effected before or after formation of the membrane. The membranes may be prepared by casting a solution of the polyamide on a support and evaporating the solvent; the solvent may be only partially removed and the film, with or without its support, immersed in a non-solvent. Pore-forming agents e.g. fine sodium chloride or magnesium perchlorate can be included in the casting solution and then leached from the film. The membranes are used for the desalination of sea water by reverse osmosis in plane or tubular shape e.g. as bundles of hollow fibres.</p> |
