US5498335A
Expired / Lapsed
US
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Process for forming porous polmyeric product from a nonporous polymeric composition and product
Assignee: EMD Millipore Corp
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Filing: 1993-07-21
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Granted: 1996-03-12
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Expires: 2013-07-21
Abstract
Abstract A product having a porous polymeric structure is formed from a non-porous polymeric sheet by sequential contact of the non-porous sheet with a solvent for the sheet and then a non-solvent for the sheet. The porous product can be porous through all or a portion of its thickness.
Inventors
- 👤 Wilson Moya
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 15:22
CPC Classifications
C; C08; C08J; C08J7/00; C08J7/02; B; B01; B01D; B01D67/00; B01D67/0002; B01D67/0023; B01D69/00; B01D69/02; B01D69/06; B01D69/08; B29; B29C; B29C71/00; B29C71/0009; B01D2323/00; B01D2323/15; B01D2323/16; B01D2323/219; B01D2323/22
Claims Analysis
Total Claims: 37
Claim 1
Independent Claim
70 words
A porous polymeric membrane structure having a thickness, said membrane having a porous structure with pores having non-directional tortuous pathways on a first surface, on a second surface and throughout a portion of said thickness, the remaining portion of said thickness comprising an intermediate nonporous polymeric composition, said porous structure being derived directly from a solid nonporous homogeneous polymeric composition and said pathways formed by precipitation of said polymeric composition.
Claim 2
Dependent Claim
70 words
A porous polymeric membrane structure having a thickness, said membrane having a porous structure with pores having non-directional tortuous pathways on a first surface, on a second surface and throughout a portion of said thickness, the remaining portion of said thickness comprising an intermediate nonporous polymeric composition, said porous structure being derived directly from a solid nonporous homogeneous polymeric composition and said pathways formed by precipitation of said polymeric composition.
Claim 3
Dependent Claim
65 words
A porous polymeric membrane structure having a thickness, said membrane having a porous structure with pores having non-directional tortuous pathways on a first surface and throughout a portion of said thickness, the remaining portion of said thickness comprising a nonporous polymeric composition said porous structure being derived directly from a solid nonporous homogeneous polymeric composition and said pathways formed by precipitation of said polymeric composition.
Claim 4
Dependent Claim
65 words
A porous polymeric membrane structure having a thickness, said membrane having a porous structure with pores having non-directional tortuous pathways on a first surface and throughout a portion of said thickness, the remaining portion of said thickness comprising a nonporous polymeric composition said porous structure being derived directly from a solid nonporous homogeneous polymeric composition and said pathways formed by precipitation of said polymeric composition.
Claim 5
Dependent Claim
19 words
The product of any one of claims 1 or 2 wherein said structure is formed of a polyamide composition.
Claim 6
Dependent Claim
20 words
The membrane structure of any one of claims 1 or 2 wherein said structure is formed of a nitrocellulose composition.
Claim 7
Dependent Claim
20 words
The membrane structure of any one of claims 1 or 2 wherein said structure is formed of a polycarbonate composition.
Claim 8
Dependent Claim
21 words
The membrane structure of any one of claims 1 or 2 wherein said structure is formed of a poly(vinyl chloride) composition.
Claim 9
Dependent Claim
21 words
The membrane structure of any one of claims 1 or 2 wherein said structure is formed of a polyvinylidene fluoride composition.
Claim 10
Dependent Claim
20 words
The membrane structure of any one of claims 1 or 2 wherein said structure is formed of a polysulfone composition.
Claim 11
Dependent Claim
21 words
The membrane structure of any one of claims 1 or 2 wherein said structure is formed of a cellulose acetate composition.
Claim 12
Dependent Claim
20 words
The membrane structure of any one of claims 1 or 2 wherein said structure is formed of a polystyrene composition.
Claim 13
Dependent Claim
20 words
The membrane structure of any one of claims 1 or 8 wherein said structure is formed of a polyolefin composition.
Claim 14
Dependent Claim
20 words
The membrane structure of any one of claims 1 or 8 wherein said structure is formed of a polyacrylic composition.
Claim 15
Dependent Claim
20 words
The membrane structure of any one of claims 1 or 8 wherein said structure is formed of a polymethacrylic composition.
Claim 16
Dependent Claim
60 words
A porous polymeric structure derived from a solid nonporous homogeneous polymeric structure wherein said solid nonporous homogeneous polymeric structure comprises a plurality of nonporous polymeric sheets, said porous polymer structure comprises a plurality of porous polymeric sheets laminated together, said porous polymeric structure being derived directly from said nonporous homogeneous polymeric structure and having pores formed of nondirectional tortuous pathways.
Claim 17
Dependent Claim
60 words
A porous polymeric structure derived from a solid nonporous homogeneous polymeric structure wherein said solid nonporous homogeneous polymeric structure comprises a plurality of nonporous polymeric sheets, said porous polymer structure comprises a plurality of porous polymeric sheets laminated together, said porous polymeric structure being derived directly from said nonporous homogeneous polymeric structure and having pores formed of nondirectional tortuous pathways.
Claim 18
Dependent Claim
74 words
A porous polymeric structure derived from a solid nonporous homogeneous polymeric structure wherein said solid nonporous homogeneous polymeric structure comprises a plurality of nonporous polymeric sheets, said porous structure comprises a plurality of porous polymeric sheets laminated together and having at least a portion of one surface of said porous polymeric sheets exposed, said porous polymeric structure being derived directly from said nonporous homogeneous polymeric structure and having pores formed of nondirectional tortuous pathways.
Claim 19
Dependent Claim
74 words
A porous polymeric structure derived from a solid nonporous homogeneous polymeric structure wherein said solid nonporous homogeneous polymeric structure comprises a plurality of nonporous polymeric sheets, said porous structure comprises a plurality of porous polymeric sheets laminated together and having at least a portion of one surface of said porous polymeric sheets exposed, said porous polymeric structure being derived directly from said nonporous homogeneous polymeric structure and having pores formed of nondirectional tortuous pathways.
Claim 20
Dependent Claim
20 words
The porous polymeric structure of any one of claims 1, 2, 14 or 15 wherein said pores are microporous pores.
Claim 21
Dependent Claim
20 words
The porous polymeric structure of any one of claims 1, 2, 14 or 15 wherein said pores are ultrafiltration pores.
Claim 22
Dependent Claim
20 words
The membrane structure of any one of claims 1 or 2 wherein said structure is formed from a polyethersulfone composition.
Claim 23
Dependent Claim
77 words
The process for forming a porous polymeric structure from a solid homogeneous nonporous polymeric structure having a homogeneous composition which comprises contacting said nonporous polymeric structure with a solvent for said nonporous polymeric structure to effect gelling of at least a portion of said nonporous polymeric structure to form a gelled structure and contacting said gelled structure with a nonsolvent for said gelled structure to effect precipitation of said gelled structure to form a porous polymeric structure.
Claim 24
Dependent Claim
77 words
The process for forming a porous polymeric structure from a solid homogeneous nonporous polymeric structure having a homogeneous composition which comprises contacting said nonporous polymeric structure with a solvent for said nonporous polymeric structure to effect gelling of at least a portion of said nonporous polymeric structure to form a gelled structure and contacting said gelled structure with a nonsolvent for said gelled structure to effect precipitation of said gelled structure to form a porous polymeric structure.
Claim 25
Dependent Claim
15 words
The process of claim 19 wherein said structure is in the form of a sheet.
Claim 26
Dependent Claim
15 words
The process of claim 19 wherein gelling is effected throughout the thickness of said structure.
Claim 27
Dependent Claim
34 words
The process of claim 19 wherein gelling is effected from two surfaces of a nonporous sheet through a portion of the thickness of said sheet to form a structure having an intermediate nonporous layer.
Claim 28
Dependent Claim
39 words
The process of claim 19 wherein gelling is effected from one surface of a nonporous sheet through a portion of the thickness of said sheet to form a structure having a first porous surface and a second nonporous surface.
Claim 29
Dependent Claim
15 words
The process of claim 19 wherein said structure is in the form of solid fiber.
Claim 30
Dependent Claim
16 words
The process of claim 19 wherein said structure is in the form of a hollow fiber.
Claim 31
Dependent Claim
25 words
The process of claim 19 wherein said nonporous structure comprises a plurality of sheets and said porous structure comprises a plurality of sheets laminated together.
Claim 32
Dependent Claim
64 words
The process for forming a porous structure from a solid homogeneous nonporous polymeric structure which comprises contacting said nonporous polymeric structure with a solvent for said nonporous polymeric structure to effect gelling of at least a portion of said nonporous polymeric structure to form a gelled structure and evaporating said solvent to effect precipitation of said gelled structure to form a porous polymeric structure.
Claim 33
Dependent Claim
64 words
The process for forming a porous structure from a solid homogeneous nonporous polymeric structure which comprises contacting said nonporous polymeric structure with a solvent for said nonporous polymeric structure to effect gelling of at least a portion of said nonporous polymeric structure to form a gelled structure and evaporating said solvent to effect precipitation of said gelled structure to form a porous polymeric structure.
Claim 34
Dependent Claim
70 words
The process for forming a porous structure from a solid homogeneous nonporous polymeric structure which comprises contacting said nonporous polymeric structure with a solvent for said nonporous polymeric structure to effect gelling of at least a portion of said nonporous polymeric structure to form a gelled structure and exposing said gelled structure to a humid gaseous composition to effect precipitation of said gelled structure to form a porous polymeric structure.
Claim 35
Dependent Claim
70 words
The process for forming a porous structure from a solid homogeneous nonporous polymeric structure which comprises contacting said nonporous polymeric structure with a solvent for said nonporous polymeric structure to effect gelling of at least a portion of said nonporous polymeric structure to form a gelled structure and exposing said gelled structure to a humid gaseous composition to effect precipitation of said gelled structure to form a porous polymeric structure.
Claim 36
Dependent Claim
68 words
The process for forming a porous structure from a solid homogeneous nonporous polymeric structure which comprises contacting said nonporous polymeric structure with a solvent for said nonporous polymeric structure to effect gelling of at least a portion of said nonporous polymeric structure to form a gelled structure by changing the temperature of said gelled structure to effect precipitation of said gelled structure to form a porous polymeric structure.
Claim 37
Dependent Claim
68 words
The process for forming a porous structure from a solid homogeneous nonporous polymeric structure which comprises contacting said nonporous polymeric structure with a solvent for said nonporous polymeric structure to effect gelling of at least a portion of said nonporous polymeric structure to form a gelled structure by changing the temperature of said gelled structure to effect precipitation of said gelled structure to form a porous polymeric structure.
References Cited (Backward Citations)
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