Semipermeable composite membrane
Abstract
Abstract A semipermeable composite membrane on a microporous substrate, such as a polysulphone membrane having on its surface a semipermeable membrane being the reaction product of a polyamine, a water soluble polymer of formula 1 ##STR1## wherein R is hydrogen or an hydrocarbongroup, x is 0-99.9%, and y is 100-x mol. % and n indicates the molecular weight and of a crosslinking agent containing a polyfunctional group having reacted with the amino groups of the polyamine and of the polymer. In the formula 1 preferably R is an alkylgroup of 1-5 carbon atoms, particularly methyl, and n is equivalent to a mol. weight of more than 10.000. The water soluble polymer is advantageously a mixture of a polymer of formula 1 wherein x and y are both 50 mol. % and a polymer of formula 2, ##STR2## this last mentioned polymer being preferably obtained by hydrolysis of a compound of formula 1. The degree of hydrolysis is preferably 70 to 99.9%. The crosslinking agent is preferably a mixture of iso phtaloylchloride and trimesoylchloride; the polyamine is preferably an azolalkane compound having terminal amino groups with a straight chain comprising 8 to 24 carbon atoms, particularly 1.10-diamino-4.7-diazadecane; 1.14-diamino-4.8.11-triazatetradecane and 1.18-diamino-4.8.11.15-tetraazooctadecane. The flux of the membrane is at least 40 l/m 2 .h and the salt retention at least 90%.
Inventors
- 👤 Henricus C. W. M. Buys
- 👤 Aart J. Naaktgeboren
- 👤 Aris Van Elven
- 👤 Dirk A. Noordegraaf
Bibliographic Details
Claims Analysis
Total Claims: 11References Cited (Backward Citations)
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