1. A method for making polymer membranes from aromatic polyimide membranes by thermal treating and UV crosslinking comprising:
a) first providing or synthesizing a polyimide polymer wherein said polyimide polymer contains pendent \u2014OH or \u2014SH groups ortho to a heterocyclic imide nitrogen and UV cross-linkable functional groups in a polymer backbone;
b) fabricating polyimide membranes from the polyimide polymer;
c) heating the polyimide membranes at a temperature between about 300\xb0 and 600\xb0 C. under inert atmosphere or vacuum for about 30 seconds to one hour to produce a heated polyimide membrane; and
d) exposing said heated polyimide membranes to a crosslinking treatment.
2. The method of claim 1 wherein said crosslinking treatment is selected from the group consisting of chemical crosslinking and UV radiation.
3. The method of claim 1 further comprising coating a top surface of the polymer membranes made from aromatic polyimide membranes by thermal treating and UV crosslinking with a thin layer of high permeability material selected from the group consisting of a polysiloxane, a fluoro-polymer, a thermally curable silicone rubber, and a UV radiation curable epoxy silicone.
4. The method of claim 1 wherein said polyimide polymer comprises a plurality of repeating units of a formula (I), wherein said formula (I) is:
where \u2014X1\u2014 of said formula (I) is
or mixtures thereof, \u2014X2\u2014 of said formula (I) is either the same as \u2014X1\u2014 or selected from
or mixtures thereof, \u2014Y\u2014 of said formula (I) is
or mixtures thereof, \u2014Z\u2014, \u2014Z\u2032\u2014, and \u2014Z\u2033\u2014 are independently \u2014O\u2014 or \u2014S\u2014, \u2014R\u2014 is
or mixtures thereof.
5. The method of claim 1 wherein said polyimide polymer is selected from the group consisting of poly3,3\u2032,4,4\u2032-benzophenonetetracarboxylic dianhydride-2,2-bis(3-amino-4-hydroxyphenyl)-hexafluoropropane (poly(BTDA-APAF)), poly(3,3\u2032,4,4\u2032-benzophenonetetracarboxylic dianhydride-3,3\u2032-dihydroxy-4,4\u2032-diamino-biphenyl) (poly(BTDA-HAB)), poly3,3\u2032,4,4\u2032-diphenylsulfone tetracarboxylic dianhydride-2,2-bis(3-amino-4-hydroxyphenyl)-hexafluoropropane (poly(DSDA-APAF)), poly(3,3\u2032,4,4\u2032-diphenylsulfone tetracarboxylic dianhydride-2,2-bis(3-amino-4-hydroxyphenyl)-hexafluoropropane-3,3\u2032-dihydroxy-4,4\u2032-diamino-biphenyl) (poly(DSDA-APAF-HAB)), poly2,2\u2032-bis-(3,4-dicarboxyphenyl) hexafluoropropane dianhydride-3,3\u2032,4,4\u2032-benzophenonetetracarboxylic dianhydride-2,2-bis(3-amino-4-hydroxyphenyl)-hexafluoropropane (poly(6FDA-BTDA-APAF)), poly4,4\u2032-oxydiphthalic anhydride-2,2-bis(3-amino-4-hydroxyphenyl)-hexafluoropropane (poly(ODPA-APAF)), poly4,4\u2032-oxydiphthalic anhydride-2,2-bis(3-amino-4-hydroxyphenyl)-hexafluoropropane-3,3\u2032-dihydroxy-4,4\u2032-diamino-biphenyl (poly(ODPA-APAF-HAB)), poly3,3\u2032,4,4\u2032-benzophenonetetracarboxylic dianhydride-2,2-bis(3-amino-4-hydroxyphenyl)-hexafluoropropane-3,3\u2032-dihydroxy-4,4\u2032-diamino-biphenyl (poly(BTDA-APAF-HAB)), and poly(4,4\u2032-bisphenol A dianhydride-3,3\u2032,4,4\u2032-benzophenonetetracarboxylic dianhydride-2,2-bis(3-amino-4-hydroxyphenyl)-hexafluoropropane (poly(BPADA-BTDA-APAF)).
6. A process for separating at least one gas or liquid from a mixture of gases or liquids using a polymer membrane prepared from an aromatic polyimide membrane by thermal treating and UV crosslinking, said process comprising:
a) providing a polymer membrane prepared from polyimide polymers comprising cross-linkable functional groups found in a backbone of said cross-linkable polyimide polymers and pendent \u2014OH or \u2014SH groups ortho to a heterocyclic imide nitrogen wherein said polyimide polymers are first subjected to a heat treatment to produce a heat treated polyimide polymer membrane and then said heat treated polyimide polymer membrane is subjected to a crosslinking treatment wherein said polymer membrane prepared from the aromatic polyimide membrane by thermal treating and UV crosslinking is permeable to at least one gas or liquid;
b) contacting a mixture of gases or liquids on one side of the polymer membrane prepared from the aromatic polyimide membrane by thermal treating and UV crosslinking to cause at least one gas or liquid to permeate the membrane; and
c) removing from an opposite side of the membrane a permeate gas or liquid composition that is a portion of said at least one gas or liquid that permeated the membrane.
7. The process of claim 6 wherein said gases are mixtures selected from the group consisting of CO2CH4, CO2N2, H2CH4, O2N2, H2SCH4, olefinparaffin, and iso paraffinsnormal paraffins.
8. The process of claim 6 wherein said gas or liquid comprises at least one volatile organic compound in an atmospheric gas.
9. The process of claim 6 wherein said gases or liquids comprise hydrogen from a hydrocarbon vapor stream.
10. The process of claim 6 wherein said gases or liquids comprise a mixture of at least one pair of gases selected from the group consisting of nitrogen and oxygen, carbon dioxide and methane, and hydrogen and methane or a mixture of carbon monoxide, helium and methane.
11. The process of claim 6 wherein said gases or liquids comprise natural gas comprising methane and at least one gas component selected from the group consisting of carbon dioxide, oxygen, nitrogen, water vapor, hydrogen sulfide, helium and other trace gases.
12. The process of claim 6 wherein said gases or liquids comprise hydrocarbon gases, carbon dioxide, hydrogen sulfide and mixtures thereof.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A peritoneal dialysis machine comprising:
a housing;
a mechanically actuated piston head extending from a pump actuator housed by the housing, the mechanically actuated piston head positioned to extend towards and away from a fluid pumping cassette, the fluid pumping cassette coupled operably to the housing such that a flexible membrane of the fluid pumping cassette faces the piston head;
a pressure sensor located adjacent to the mechanically actuated piston head so as to sense a pressure of a medical fluid moved by the mechanically actuated piston head within the fluid pumping cassette; and
a vacuum chamber formed about the mechanically actuated piston head, the vacuum chamber holding a vacuum that sucks the flexible membrane of the fluid pumping cassette onto the mechanically actuated piston head as the mechanically actuated piston head extends away from the fluid pumping cassette.
2. The peritoneal dialysis machine of claim 1, the vacuum further sucking the flexible membrane of the fluid pumping cassette onto the mechanically actuated piston head as the mechanically actuated piston head extends towards the fluid pumping cassette.
3. The peritoneal dialysis machine of claim 1, wherein the housing includes a plate mounting the pressure sensor and providing an aperture through which the mechanically actuated piston head moves towards and away from the fluid pumping cassette.
4. The peritoneal dialysis machine of claim 3, the vacuum chamber communicating with the flexible membrane of the fluid pumping cassette via at least one aperture formed in the plate of the housing.
5. The peritoneal dialysis machine of claim 3, the vacuum chamber including a vacuum chamber wall connected to the plate of the housing.
6. The peritoneal dialysis machine of claim 3, wherein the plate defines a first shape, a second shape defined by the fluid pumping cassette, the first and second shapes forming a pumping chamber.
7. The peritoneal dialysis machine of claim 6, wherein the first and second shapes are at least substantially the same.
8. The peritoneal dialysis machine of claim 3, wherein the plate further mounts a fluid valve operable with the fluid pumping cassette.
9. The peritoneal dialysis machine of claim 8, wherein the flexible membrane is operable with each of the piston head, the pressure sensor and the fluid valve.
10. The peritoneal dialysis machine of claim 1, the vacuum chamber communicating with the flexible membrane of the fluid pumping cassette via at least one aperture formed in the mechanically actuated piston head.
11. The peritoneal dialysis machine of claim 1, wherein the pump actuator is housed in the vacuum chamber.
12. A peritoneal dialysis machine comprising:
a mechanically actuated piston head extending from a pump actuator, the mechanically actuated piston head positioned to extend towards and away from a fluid pumping cassette coupled operably to the machine such that a flexible membrane of the pumping cassette faces the piston head;
a pressure sensor positioned adjacent the mechanically actuated piston head so as to sense a pressure of a medical fluid moved by the mechanically actuated piston head within the fluid pumping cassette;
a vacuum chamber formed about the mechanically actuated piston head, the vacuum chamber holding a vacuum that sucks the flexible membrane of the fluid pumping cassette onto the mechanically actuated piston head as the mechanically actuated piston head extends away from the fluid pumping cassette; and
a line occlusion test performed by the machine in which a line occlusion is determined if the pressure sensor detects a pressure rise when the piston head is extending towards the cassette to push the medical fluid out of the cassette.
13. The peritoneal dialysis machine of claim 12, which is programmed to operate the line occlusion test during a priming sequence.
14. The peritoneal dialysis machine of claim 12, the line being a patient line extending from the fluid pumping cassette.
15. The peritoneal dialysis machine of claim 12, which is configured to look for a leak by monitoring a position of the mechanically actuated piston head when it is expected that the mechanically operated piston head will be stationary.
16. The peritoneal dialysis machine of claim 15, which is configured to use the pump actuator and the mechanically actuated piston head to apply a constant force to the flexible membrane of the fluid pumping cassette while monitoring the position of the mechanically actuated piston head.
17. The peritoneal dialysis machine of claim 12, the pressure sensor positioned so as to contact the flexible membrane of the fluid pumping cassette.
18. The peritoneal dialysis machine of claim 12, wherein the line occlusion is determined if the pressure rise reads a particular level when the piston head is extending towards the cassette to push the medical fluid out of the cassette.
19. A peritoneal dialysis machine comprising:
a mechanically actuated piston head extending from a pump actuator, the mechanically actuated piston head positioned to extend towards and away from a fluid pumping cassette coupled operably to the machine such that a flexible membrane of the pumping cassette faces the piston head;
a fluid valve positioned adjacent to the piston head and operable with the fluid pumping cassette;
a vacuum chamber formed about the mechanically actuated piston head, the vacuum chamber holding a vacuum that sucks the flexible membrane of the fluid pumping cassette onto the mechanically actuated piston head as the mechanically actuated piston head extends away from the fluid pumping cassette; and
a priming procedure performed by the machine in which a position of the mechanically actuated piston head is monitored to determine when to open the fluid valve to allow communication between a pump chamber portion of the fluid pumping cassette and a line extending from the fluid pumping cassette being primed.
20. The peritoneal dialysis machine of claim 19, wherein the fluid valve is opened to allow gravity flow to the line being primed.
21. A peritoneal dialysis machine comprising:
a mechanically actuated piston head extending from a pump actuator, the mechanically actuated piston head positioned to extend towards and away from a fluid pumping cassette coupled operably to the machine such that a flexible membrane of the pumping cassette faces the piston head;
a pressure sensor positioned adjacent the mechanically actuated piston head so as to sense a pressure of a medical fluid moved by the mechanically actuated piston head within the fluid pumping cassette;
a vacuum chamber formed about the mechanically actuated piston head, the vacuum chamber holding a vacuum that sucks the flexible membrane of the fluid pumping cassette onto the mechanically actuated piston head as the mechanically actuated piston head extends away from the fluid pumping cassette; and
a leak test performed by monitoring a position of the mechanically actuated piston head while causing the mechanically actuated piston head to apply a constant force to the flexible membrane of the fluid pumping cassette when it is expected that the mechanically actuated piston head will be held stationary.
22. The peritoneal dialysis machine of claim 21, wherein a leak is determined if the piston head moves.