US3948823A
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Method of making permselective interpolymer membranes
Assignee: Honeywell International Inc
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Filing: 1972-08-01
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Granted: 1976-04-06
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Expires: 1992-08-01
Abstract
Abstract Novel cross-linked interpolymer membranes of substantially improved efficiency and durability are prepared from a co-mixture of a hydrophilic polymer of [1, ω-alkylene(2,6-diketopiperazine)-1,4-dicarboxamide] and a hydrophobic polymer such as polyvinylidene fluoride, by dissolving these polymers in a suitable solvent, forming films of suitable thickness from the solution and thereafter preferably crosslinking the dissolved mixture.
Inventors
- 👤 Lester T. C. Lee
- 👤 Kang-Jen Liu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:09
CPC Classifications
C; C08; C08L; C08L63/00; C08L63/04; B; B01; B01D; B01D71/00; B01D71/06; B01D71/30; B01D71/32; B01D71/34; B01D71/56; C08L77/00
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
166 words
A process for the manufacture of a substantially macroscopically homogeneous membrane comprising forming a common solution of (a) from about 5 to about 80 percent of a matrix polymer; (b) from about 5 to about 95 percent of poly[1,ω-alkylene (2,6-diketopiperazine)1,4-dicarboxamide] selected from the group consisting of those having the formulae: ##SPC4## wherein R 1 and R 3 are substituents selected from the group consisting of phenylene radicals and alkylene radicals having 1 to 12 carbon atoms and R 2 ,R 4 and R 5 are substituents selected from the group consisting of aliphatic and aromatic diradicals having 1 to 12 carbon atoms and may include oxygen, sulfur, and nitrogen atoms, wherein said matrix polymer (a) is compatible with the polymer (b), and wherein the ratio of (a) to (b) produces a membrane with a water content of from about 15 percent to about 75 percent, forming a membrane of a desired thickness, and crosslinking the membrane to convert it into an insoluble membrane of predetermined porosity.
Claim 2
Dependent Claim
166 words
A process for the manufacture of a substantially macroscopically homogeneous membrane comprising forming a common solution of (a) from about 5 to about 80 percent of a matrix polymer; (b) from about 5 to about 95 percent of poly[1,ω-alkylene (2,6-diketopiperazine)1,4-dicarboxamide] selected from the group consisting of those having the formulae: ##SPC4## wherein R 1 and R 3 are substituents selected from the group consisting of phenylene radicals and alkylene radicals having 1 to 12 carbon atoms and R 2 ,R 4 and R 5 are substituents selected from the group consisting of aliphatic and aromatic diradicals having 1 to 12 carbon atoms and may include oxygen, sulfur, and nitrogen atoms, wherein said matrix polymer (a) is compatible with the polymer (b), and wherein the ratio of (a) to (b) produces a membrane with a water content of from about 15 percent to about 75 percent, forming a membrane of a desired thickness, and crosslinking the membrane to convert it into an insoluble membrane of predetermined porosity.
Claim 3
Dependent Claim
41 words
The process of claim 1 wherein said polymers (a) and (b) are dissolved to form a common solution and thereafter casting a film of desired thickness and prior to crosslinking said film, drying said film until a desired porosity is attained.
Claim 4
Dependent Claim
50 words
The process of claim 1 wherein said membrane is formed from a solution of polymers (a) and (b) in which a chemical crosslinking agent has been incorporated and drying said membrane below the active temperature of the crosslinking agent until at least about 90 percent of the solvent is removed.
Claim 5
Dependent Claim
51 words
The process of claim 2 wherein the matrix polymer is present in amounts of from about 5 to about 80 percent, the 1, ω -alkylene(2,6-diketopiperazine)1,4-dicarboxamide polymer (b) in amounts from about 5 to about 95 percent and a chemical crosslinking agent (c) is present in amounts of at least 0.5 percent.
Claim 6
Dependent Claim
64 words
The process of claim 1 wherein the 1, ω -alkylene-(2,6-diketopiperazine)1,4-dicarboxamide polymer is ##SPC5## wherein R 1 represents a phenylene radical or an alkylene radical having 1 to 12 carbon atoms and R 2 represents an organic radical selected from the group consisting of aliphatic and aromatic diradicals having 1 to 12 carbon atoms and diradicals of this class containing oxygen, sulfur and nitrogen atoms.
Claim 7
Dependent Claim
67 words
The process of claim 1 wherein the 1, ω -alkylene-(2,6-diketopiperazine)1,4-dicarboxamide polymer is ##SPC6## wherein R 3 is a phenylene radical or an alkylene radical having 1 to 12 carbon atoms and R 4 and R 5 represent an organic radical selected from the group consisting of aliphatic and aromatic diradicals having 1 to 12 carbon atoms and diradicals of this class containing oxygen, sulfur, and nitrogen atoms.
Claim 8
Dependent Claim
71 words
A membrane comprising a homogeneous crosslinked interpolymer of (a) a matrix polymer and (b) a polymer forming a common solution with (a) and consisting essentially of a 1,ω-alkylene(2,6-diketopiperazine) 1,4-dicarboxamide polymer characterized by a hydraulic permeability of at least 10.sup. -5 cm/sec.atm., a water content of from about 15 percent to about 75 percent, and characterized by a porosity which produces a salt rejection of at least 1.0 percent at 60 psi.
Claim 9
Dependent Claim
71 words
A membrane comprising a homogeneous crosslinked interpolymer of (a) a matrix polymer and (b) a polymer forming a common solution with (a) and consisting essentially of a 1,ω-alkylene(2,6-diketopiperazine) 1,4-dicarboxamide polymer characterized by a hydraulic permeability of at least 10.sup. -5 cm/sec.atm., a water content of from about 15 percent to about 75 percent, and characterized by a porosity which produces a salt rejection of at least 1.0 percent at 60 psi.
Claim 10
Dependent Claim
70 words
The polymeric membrane of claim 7 wherein the 1,ω-alkylene(2,6-diketopiperazine)1,4-dicarboxamide polymer incorporated within the crosslinked network has the formula ##SPC7## wherein R 1 represents a phenylene radical or an alkylene radical having 1 to 6 carbon atoms and R 2 represents an organic radical selected from the group consisting of aliphatic and aromatic diradicals having 1 to 12 carbon atoms and diradicals of this class containing oxygen, sulfur and nitrogen atoms.
Claim 11
Dependent Claim
73 words
The polymeric membrane of claim 7 wherein the 1,ω-alkylene(2,6-diketopiperazine)1,4-dicarboxamide polymer incorporated within the crosslinked network has the formula ##SPC8## wherein R 3 is a phenylene radical or an alkylene radical having 1 to 12 carbon atoms and R 4 and R 5 represent an organic radical selected from the group consisting of aliphatic and aromatic diradicals having 1 to 12 carbon atoms and diradicals of this class containing oxygen, sulfur and nitrogen atoms.
References Cited (Backward Citations)
US3728348A
Cited
US3719640A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-04-06 | 1979-10-06 | 1980-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-04-06 | 1983-10-06 | 1984-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-04-06 | 1987-10-06 | 1988-04-06 | $7700.00 | Window Closed / Lapsed |