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Patent US5047437A successfully refreshed from Google Patents.
US5047437A
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US
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Porous polyacrylonitrile beads and process for their production
Assignee: Wyeth Holdings LLC
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Filing: 1988-11-23
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Granted: 1991-09-10
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Expires: 2008-11-23
Abstract
Abstract Isotropic porous polymer beads having a high surface porosity and large pore diameters from about 0.002 to about 5 microns are produced from solutions of an acrylonitrile polymer or a copolymer by a thermally-induced phase separation process. The use of mixed solvent-non-solvent combinations as solvents for the polymers, produces high pore content, substantially spherical beads having a morphology ideally suited to the chromatography of large molecules, such as proteins, and for enzyme-binding.
Inventors
- 👤 Michael T. Cooke
- 👤 Laura J. Hiscock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:48
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/12; C08J3/14; B; B01; B01J; B01J20/00; B01J20/22; B01J20/26; C08J9/00; C08J9/28; C08J2333/00; C08J2333/18; C08J2333/20
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
47 words
A substantially skinless highly porous bead comprising a homopolymer or copolymer of an acrylonitrile, said bead being substantially non-swellable in water, being substantially isotropic, having pores of not substantially greater than about 5 microns in diameter and a pore volume not substantially less than about 1.5 ml/g.
Claim 2
Dependent Claim
47 words
A substantially skinless highly porous bead comprising a homopolymer or copolymer of an acrylonitrile, said bead being substantially non-swellable in water, being substantially isotropic, having pores of not substantially greater than about 5 microns in diameter and a pore volume not substantially less than about 1.5 ml/g.
Claim 3
Dependent Claim
12 words
A porous bead as defined in claim 1 which is substantially spherical.
Claim 4
Dependent Claim
22 words
A porous bead as described in claim 1 wherein said copolymer comprises from about 45 to about 99.5 mole percent of acrylonitrile.
Claim 5
Dependent Claim
17 words
A porous bead as defined in claim 1 wherein the pores are substantially isotropic throughout the bead.
Claim 6
Dependent Claim
18 words
A porous bead as defined in claim 1 wherein the pore volume is less than about 5 ml/g.
Claim 7
Dependent Claim
22 words
A porous bead as defined in claim 1 wherein the average bead diameter is from about 5 microns to about 2 millimeters.
Claim 8
Dependent Claim
21 words
A porous bead as defined in claim 5 wherein the average bead diameter is from about 5 to about 150 microns.
Claim 9
Dependent Claim
21 words
A porous bead as defined in claim 6 wherein the average bead diameter is from about 5 to about 20 microns.
Claim 10
Dependent Claim
21 words
A porous bead as defined in claim 6 wherein the average bead diameter is from about 20 to about 150 microns.
Claim 11
Dependent Claim
22 words
A porous bead as defined in claim 1 wherein the average pore diameter is from about 0.002 microns to about 5 microns.
Claim 12
Dependent Claim
22 words
A porous bead as defined in claim 1 wherein the average pore diameter is from about 0.002 microns to about 0.1 microns.
Claim 13
Dependent Claim
22 words
A porous bead as defined in claim 9 wherein the average pore diameter is from about 0.1 micron to about 1 micron.
Claim 14
Dependent Claim
76 words
A porous bead as defined in claim 1 wherein said polyacrylonitrile copolymer comprises an acrylonitrile copolymerized with a (C 2 -C 6 ) monoolefin, a vinylaromatic, a vinylaminoaromatic, a vinyl halide, a (C 1 -C 6 ) alkyl (meth)acrylate, a (meth)acrylamide, a vinyl pyrrolidone, a vinyl pyridine, a (C 1 -C 6 )hydroxyalkyl (meth)acrylate, a (meth)acrylic acid, an acrylamidomethylpropylsulfonic acid, an N-hydroxy-containing (C 1 -C 6 ) alkyl(meth)acrylamide, or a mixture of any of the foregoing.
Claim 15
Dependent Claim
18 words
A porous bead as defined in claim 1 said pores being at least partially filled with a compound.
Claim 16
Dependent Claim
37 words
A porous bead as defined in claim 14 wherein said compound is selected from a protein, an enzyme, a peptide, a polysaccharide, a nucleic acid, a dye, a pigment or a mixture of any of the foregoing.
Claim 17
Dependent Claim
14 words
A porous bead as defined in claim 15 wherein said compound comprises a protein.
Claim 18
Dependent Claim
23 words
A porous bead as defined in claim 15 wherein the pore diameter is at least about 3 times the diameter of said compound.
Claim 19
Dependent Claim
88 words
A process for the preparation of isotropic porous polymer beads, said process comprising (i) heating and mixing an acrylonitrile homopolymer or copolymer with a mixture comprising a solvent and a non-solvent for the polymer to form a homogeneous solution: (ii) breaking the homogeneous solution into droplets; (iii) cooling the droplets, optionally in the presence of an inert liquid, to bring about phase separation and solidification of the polymer in the droplets; (iv) separating the droplets from any inert liquid and the solvent-non-solvent mixture to produce isotropic porous beads.
Claim 20
Dependent Claim
88 words
A process for the preparation of isotropic porous polymer beads, said process comprising (i) heating and mixing an acrylonitrile homopolymer or copolymer with a mixture comprising a solvent and a non-solvent for the polymer to form a homogeneous solution: (ii) breaking the homogeneous solution into droplets; (iii) cooling the droplets, optionally in the presence of an inert liquid, to bring about phase separation and solidification of the polymer in the droplets; (iv) separating the droplets from any inert liquid and the solvent-non-solvent mixture to produce isotropic porous beads.
Claim 21
Dependent Claim
41 words
A process as defined in claim 18 wherein said solvent comprises dimethyl sulfone, the non-solvent comprises urea, water, propylene glycol, ethylene glycol or a mixture thereof and step (i) is carried out at a temperature of at least about 130° C.
Claim 22
Dependent Claim
19 words
A process as defined in claim 18 wherein the inert liquid comprises mineral oil, heptane or a mixture thereof.
Claim 23
Dependent Claim
32 words
A process as defined in claim 19 wherein the beads are extracted with a non-solvent for the polymer, said non-solvent comprising acetone, methanol water or a mixture of any of the foregoing.
Claim 24
Dependent Claim
21 words
A process as defined in claim 18 wherein said homogeneous solution contains less than about 10 weight percent homopolymer or copolymer.
Claim 25
Dependent Claim
16 words
A process as defined in claim 18 wherein said isotropic porous polymer beads are substantially skinless.
Claim 26
Dependent Claim
35 words
The process as defined in claim 18 wherein said homogeneous mixture in step (i) contains less than about 10 weight percent total homopolymer or copolymer solids and the isotropic porous polymer beads are substantially skinless.
Claim 27
Dependent Claim
8 words
The product of the process of claim 18.
Claim 28
Dependent Claim
8 words
The product of the process of claim 22.
Claim 29
Dependent Claim
8 words
The product of the process of claim 24.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-09-09 | 1995-03-11 | 1995-09-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-09-09 | 1999-03-11 | 1999-09-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-09-09 | 2003-03-11 | 2003-09-10 | $7700.00 | Window Closed / Lapsed |