US4661526A
Expired / Lapsed
US
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Cross linked porous membranes
Assignee: Memtec Ltd
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Filing: 1984-01-26
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Granted: 1987-04-28
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Expires: 2004-01-26
Abstract
Abstract PCT No. PCT/AU84/00015 Sec. 371 Date Oct. 1, 1984 Sec. 102(e) Date Oct. 1, 1984 PCT Filed Jan. 26, 1984 PCT Pub. No. WO84/03054 PCT Pub. Date Aug. 16, 1984.A polymeric porous membrane having a matrix made from an aliphatic thermoplastic polyamide or from an aliphatic thermoplastic polyamide/polyimide copolymer which has both relatively non-crystalline and relatively crystalline portions. The pores in the membrane are defined by spaces between the relatively crystalline portions and at least some of the relatively crystalline portions are linked together by the reaction of a bis-aldehyde with the membrane matrix.
Inventors
- 👤 Douglas L. Ford
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 13:47
CPC Classifications
B; B01; B01D; B01D67/00; B01D67/0081; B01D67/0093; B01D67/00931; B01D71/00; B01D71/06; B01D71/56; B01D71/58; B01D71/62; B01D71/64; B01D71/76; C; C08; C08G; C08G69/00; C08G69/48; C08G73/00; C08G73/06; C08G73/10; C08G73/14; C08J; C08J5/00; C08J5/20; C08J5/22; C08J5/2206; C08J5/2218; C08J5/2256; C12; C12N; C12N11/00; C12N11/02; C12N11/08; C12N11/089; C12N11/096; B01D2323/00; B01D2323/30; C08J2379/00; C08J2379/02
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
176 words
A method of preparing a porous membrane comprising the steps of: (i) dissolving a thermoplastic polyamide or a thermoplastic polyamide/polyimide copolymer which has both relatively non-crystalline and relatively crystalline portions into a solvent under conditions of temperature and time which cause the relatively non-crystalline portions of the polyamide or copolymer to dissolve while at least a part of the relatively crystalline portions of the polyamide or copolymer do not dissolve, but form a colloidal dispersion in said solvent, wherein the said thermoplastic polyamide is a polyamide 6 or polyamide 6,6, and wherein the said polyamide/polyimide copolymer is a polyamide 6/polyimide copolymer or a polyamide 6,6/polyimide copolymer; (ii) forming said colloidal dispersion and solvent into a film and thereafter causing precipitation of at least part of the dissolved non-crystalline portions in the film to form a porous membrane matrix in which the pores are defined by spaces between the relatively crystalline portions, and, (iii) reacting the membrane matrix with an aldehyde as herein defined to link at least some of the relatively crystalline portions with the aldehyde.
Claim 2
Independent Claim
176 words
A method of preparing a porous membrane comprising the steps of: (i) dissolving a thermoplastic polyamide or a thermoplastic polyamide/polyimide copolymer which has both relatively non-crystalline and relatively crystalline portions into a solvent under conditions of temperature and time which cause the relatively non-crystalline portions of the polyamide or copolymer to dissolve while at least a part of the relatively crystalline portions of the polyamide or copolymer do not dissolve, but form a colloidal dispersion in said solvent, wherein the said thermoplastic polyamide is a polyamide 6 or polyamide 6,6, and wherein the said polyamide/polyimide copolymer is a polyamide 6/polyimide copolymer or a polyamide 6,6/polyimide copolymer; (ii) forming said colloidal dispersion and solvent into a film and thereafter causing precipitation of at least part of the dissolved non-crystalline portions in the film to form a porous membrane matrix in which the pores are defined by spaces between the relatively crystalline portions, and, (iii) reacting the membrane matrix with an aldehyde as herein defined to link at least some of the relatively crystalline portions with the aldehyde.
Claim 3
Dependent Claim
12 words
A method according to claim 1 wherein the aldehyde is a bis-aldehyde.
Claim 4
Dependent Claim
20 words
A method according to claim 2 wherein the bis-aldehyde is glutaraldehyde, glyoxal, succindialdehyde, alpha-hydroxyadipaldehyde, terephthaldialdehyde or phthaldialdehyde or mixtures thereof.
Claim 5
Dependent Claim
21 words
A method according to claim 1 wherein the aldehyde is derived from a bis-aldehyde polymer, an acetal or an acetal ester.
Claim 6
Dependent Claim
28 words
A method according to claim 2 wherein aldehyde reaction step is so controlled that from 10% to 25% of the aldehyde chains are not linked at one end.
Claim 7
Dependent Claim
26 words
A method according to claim 5 including the step of reacting at least some of the free ends of the single-link aldehyde chains with a phenol.
Claim 8
Dependent Claim
32 words
A method according to claim 6 wherein the phenol is selected from the group comprising resorcinol, diphenylol propane, tannic acid, pyrogallol, hydroquinone, meta-cresol and naphthol as well as derivatives or mixtures thereof.
Claim 9
Dependent Claim
28 words
A method according to claim 5 including the step of reacting at least some of the free ends of the single-link chains with a protein or polyhydric colloid.
Claim 10
Dependent Claim
27 words
A method according to claim 5 including the steps of reacting at least some of the free ends of the single-link chains with gelatin or hydroxyethyl cellulose.
Claim 11
Dependent Claim
21 words
A method according to claim 6 including the step of reacting the phenol modified chain with sodium monochloroacetate in aqueous solution.
Claim 12
Dependent Claim
19 words
A method according to claim 6 including the step of reacting the phenol modified chain with aqueous diazonium salts.
Claim 13
Dependent Claim
62 words
A method according to claim 6 including the steps of: (a) reacting at least some of the remaining reactive single-link aldehyde chains with hydrazine, (b) reacting the phenolic hydroxyl groups with epichlorohydrin, (c) reacting the resultant epoxides with diamine to fix a pre-determined concentration of amine groups and hydrolyse excess epoxide to hydroxylsing, and, (d) reacting the amine groups with excess bis(isothiocyanate).
Claim 14
Dependent Claim
19 words
A method according to claim 6 and including the step of reacting the phenol modified membrane with a bis-aldehyde.
Claim 15
Independent Claim
21 words
A method according to claims 1 to 5 wherein the membrane is reacted with sodium bisulphite, hydroxylamine-O-sulphonic acid or phenylhydrazinesulphonic acid.
Claim 16
Dependent Claim
179 words
A polymeric porous membrane prepared by a method comprising the steps of: (i) dissolving a thermoplastic polyamide or a thermoplastic polyamide/polyimide copolymer which has both relatively non-crystalline and relatively crystalline portions into a solvent under conditions of temperature and time which cause the relatively non-crystalline portions of the polyamide or copolymer to dissolve while at least a part of the relatively crystalline portions of the polyamide or copolymer do not dissolve, but form a colloidal dispersion in said solvent, wherein the said thermoplastic polyamide is a polyamide 6 or a polyamide 6,6, and wherein the said thermoplastic polyamide/polyimide copolymer is a polyamide 6/polyimide copolymer or a polyamide 6,6/polyimide copolymer, (ii) forming said colloidal dispersion and solvent into a film and thereafter causing precipitation of at least part of the dissolved non-crystalline portions in the film to form a porous membrane matrix in which the pores are defined by spaces between the relatively crystalline portions, and, (iii) reacting the membrane matrix with an aldehyde as herein defined to link at least some of the relatively crystalline portions with the aldehyde.
Claim 17
Dependent Claim
179 words
A polymeric porous membrane prepared by a method comprising the steps of: (i) dissolving a thermoplastic polyamide or a thermoplastic polyamide/polyimide copolymer which has both relatively non-crystalline and relatively crystalline portions into a solvent under conditions of temperature and time which cause the relatively non-crystalline portions of the polyamide or copolymer to dissolve while at least a part of the relatively crystalline portions of the polyamide or copolymer do not dissolve, but form a colloidal dispersion in said solvent, wherein the said thermoplastic polyamide is a polyamide 6 or a polyamide 6,6, and wherein the said thermoplastic polyamide/polyimide copolymer is a polyamide 6/polyimide copolymer or a polyamide 6,6/polyimide copolymer, (ii) forming said colloidal dispersion and solvent into a film and thereafter causing precipitation of at least part of the dissolved non-crystalline portions in the film to form a porous membrane matrix in which the pores are defined by spaces between the relatively crystalline portions, and, (iii) reacting the membrane matrix with an aldehyde as herein defined to link at least some of the relatively crystalline portions with the aldehyde.
Claim 18
Dependent Claim
21 words
The polymeric porous membrane of claim 15, said polymeric porous membrane being made by using as the said aldehyde a bis-aldehyde.
Claim 19
Dependent Claim
29 words
The polymeric porous membrane of claim 16, said polymeric porous membrane being made by using as the said bis-aldehyde, glutaraldehyde, glyoxal, succindialdehyde, alpha-hydroxyadipaldehyde, terephthaldialdehyde or phthaldialdehyde or mixtures thereof.
Claim 20
Dependent Claim
32 words
The polymeric porous membrane of claim 15, said polymeric porous membrane being made by using as the said aldehyde an aldehyde derived from a bis-aldehyde polymer, an acetal or an acetal ester.
Claim 21
Dependent Claim
35 words
The polymeric porous membrane of claim 16, said polymeric porous membrane being made by controlling the aldehyde reaction step so that from 10% to 25% of the aldehyde chains are not linked at one end.
Claim 22
Dependent Claim
30 words
The polymeric porous membrane of claim 19, said polymeric porous membrane being made by reacting at least some of the free ends of the single-linked aldehyde chain with a phenol.
Claim 23
Dependent Claim
38 words
The polymeric porous membrane of claim 20, wherein the said polymeric porous membrane is made by using as the said phenol, resorcinol, diphenylol propane, tannic acid, pyrogallol, hydroquinone, metacresol and naphthol as well as derivatives or mixtures thereof.
Claim 24
Dependent Claim
32 words
The polymeric porous membrane of claim 19, said polymeric porous membrane being made by reacting at least some of the free ends of the single-link chains with a protein or polyhydric colloid.
Claim 25
Dependent Claim
31 words
The polymeric porous membrane of claim 19, said polymeric porous membrane being made by reacting at least some of the free ends of the single-link chains with gelatin or hydroxyethyl cellulose.
Claim 26
Dependent Claim
25 words
The polymeric porous membrane of claim 20, said polymeric porous membrane being made by reacting the phenol modified chain with sodium monochloroacetate in aqueous solution.
Claim 27
Dependent Claim
23 words
The polymeric porous membrane of claim 20, said polymeric porous membrane being made by reacting the phenol modified chain with aqueous diazonium salts.
Claim 28
Dependent Claim
66 words
The polymeric porous membrane of claim 20, said polymeric porous membrane being made by: (a) reacting at least some of the remaining reactive single-link aldehyde chains with hydrazine, (b) reacting the phenolic hydroxyl groups with epichlorohydrin, (c) reacting the resultant epoxides with diamine to fix a pre-determined concentration of amine groups and hydrolyzing excess epoxide to hydroxyls, and, (d) reacting the amine group with excess bis(isothiocyanate).
Claim 29
Dependent Claim
22 words
The polymeric porous membrane of claim 20, said polymeric porous membrane being made by reacting the phenol modified membrane with a bis-aldehyde.
Claim 30
Dependent Claim
26 words
The polymeric porous membrane of claim 15, said polymeric porous membrane being made by reacting the membrane with sodium bisulfide, hydroxylamine-O sulfonic acid or phenylhydrazinesulfonic acid.
References Cited (Backward Citations)
US3904519A
Cited
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