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US4721568A Expired / Lapsed US ⏱️ 0.0 years remaining

Semipermeable composite membrane

Assignee: Wafilin BV
•
Filing: 1985-08-30
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Granted: 1988-01-26
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Expires: 2005-08-30
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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

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-09 03:03
CPC Classifications
B; B01; B01D; B01D69/00; B01D69/12; B01D69/125; B01D71/00; B01D71/06; B01D71/58; B01D71/60

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 138 words
A semipermeable composite membrane having a flux of at least 40 l/m 2 .h and a salt retention of more than 89%, said composite membrane comprising a microporous substrate having on its surface a semipermeable membrane comprising a crosslinked polymer which comprises the reaction product of a mixture of (a) a water-soluble organic polymer with reactive amino groups; (b) a polyamine and (c) a crosslinking agent containing a polyfunctional group reacted with the amino groups of the organic polymer and with the polyamine, wherein the water-soluble polymer is a polymer of formula 1 ##STR6## wherein R represents hydrogen or a C 1 -C 5 alkyl group, x has a value of between 50 and 99.9 mol.% and y is 100-x mol.% and n is an integer such that the molecular weight of the polymer is more than 10,000.
Claim 2
Dependent Claim 138 words
A semipermeable composite membrane having a flux of at least 40 l/m 2 .h and a salt retention of more than 89%, said composite membrane comprising a microporous substrate having on its surface a semipermeable membrane comprising a crosslinked polymer which comprises the reaction product of a mixture of (a) a water-soluble organic polymer with reactive amino groups; (b) a polyamine and (c) a crosslinking agent containing a polyfunctional group reacted with the amino groups of the organic polymer and with the polyamine, wherein the water-soluble polymer is a polymer of formula 1 ##STR6## wherein R represents hydrogen or a C 1 -C 5 alkyl group, x has a value of between 50 and 99.9 mol.% and y is 100-x mol.% and n is an integer such that the molecular weight of the polymer is more than 10,000.
Claim 3
Dependent Claim 14 words
A semipermeable membrane according to claim 1 wherein x is at least 60 mol.%.
Claim 4
Dependent Claim 80 words
A semipermeable membrane according to claim 1, wherein the water-soluble polymer consists of a mixture of a polymer according to formula 1, wherein x and y are both 50 mol. % and R is methyl, and a polymer of formula 2, ##STR7## the polymer of formula 2 being obtained by hydrolysis of the polymer according to formula 1 wherein R is methyl, the degree of hydrolysis being 60 to 99.5% and wherein said hydrolysis replaces the group ##STR8## by H.
Claim 5
Dependent Claim 17 words
A semipermeable membrane according to claim 3 wherein the degree of hydrolysis ranges from 70 to 99.5%.
Claim 6
Dependent Claim 36 words
A semipermeable membrane according to claim 1, wherein the polyamine is selected from the group consisting of piperazine compounds and azoalkane compounds having terminal amino groups with a straight chain comprising 8 to 24 carbon atoms.
Claim 7
Dependent Claim 35 words
Semipermeable membrane according to claim 1, wherein the crosslinking agent is selected from the group consisting of isophthaloylchloride, trimesoylchloride, a thiadiazole compound having two reactive groups, a thiadiazole polyacid derivative, and a diphenylether disulphonyl halide.
Claim 8
Dependent Claim 15 words
A semipermeable membrane according to claim 1, wherein the microporous substrate is a polysulphone membrane.
Claim 9
Dependent Claim 23 words
A semipermeable membrane as claimed in claim 1 wherein the polyamine is selected from the group consisting of 1.10 diamino-4.7-diazadecane, 1.14-diamino-4.8.11-triazatetradecane, and 1.18-diamino-4.8.11.15-tetraazooctadecane.
Claim 10
Dependent Claim 20 words
A semipermeable membrane as claimed in claim 1 wherein the crosslinking agent is a mixture of isophthaloylchloride and trimesoyl chloride.
Claim 11
Dependent Claim 11 words
A semipermeable membrane according to claim 1 wherein R is methyl.

References Cited (Backward Citations)

US4302336A Cited
US4353802A Cited
US4387024A Cited
US4388189A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-01-25 1991-07-27 1992-01-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-01-25 1995-07-27 1996-01-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-01-25 1999-07-27 2000-01-26 $7700.00 Window Closed / Lapsed

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