US3985632A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Small, porous polyacrylate beads
Assignee: California Institute of Technology
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Filing: 1974-10-04
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Granted: 1976-10-12
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Expires: 1994-10-04
Abstract
Abstract Uniformly-shaped, porous, round beads are prepared by the co-polymerization of an acrylic monomer and a cross-linking agent in the presence of 0.05 to 5% by weight of an aqueous soluble polymer such as polyethylene oxide. Cross-linking proceeds at high temperature above about 50°C or at a lower temperature with irradiation. Beads of even shape and even size distribution of less than 2 micron diameter are formed. The beads will find use as adsorbents in chromatography and as markers for studies of cell surface receptors.
Inventors
- 👤 Alan Rembaum
- 👤 Shiao-Ping Siao Yen
- 👤 William J. Dreyer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 02:11
CPC Classifications
C; C08; C08J; C08J9/00; C08F; C08F20/00; C08F20/62; G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/53; G01N33/543; G01N33/54313; C08J2333/00; C08J2333/04; C08J2333/06; Y; Y10; Y10S; Y10S521/00; Y10S521/921
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
65 words
A method of preparing uniformly-shaped, porous, round beads having an average diameter below 2 microns comprising the steps of: copolymerizing a polymerizable mixture of an amino- or hydroxy-substituted acrylic monomer and a minor amount of a polyunsaturated cross-linking agent in aqueous medium containing 0.05 to 5% by weight of an aqueous soluble polyether by applying high energy radiation to the mixture; and recovering said beads.
Claim 2
Independent Claim
65 words
A method of preparing uniformly-shaped, porous, round beads having an average diameter below 2 microns comprising the steps of: copolymerizing a polymerizable mixture of an amino- or hydroxy-substituted acrylic monomer and a minor amount of a polyunsaturated cross-linking agent in aqueous medium containing 0.05 to 5% by weight of an aqueous soluble polyether by applying high energy radiation to the mixture; and recovering said beads.
Claim 3
Dependent Claim
38 words
A method according to claim 1 in which the polyether is a polyalkylene oxide having a molecular weight from 300,000 to 10,000,000 and is present in the polymerizable mixture in an amount from 0.2 to 2% by weight.
Claim 4
Dependent Claim
30 words
A method according to claim 2 in which the polyether is a polymer of ethylene oxide, propylene oxide or mixtures thereof and the molecular weight is from 400,000 to 6,000,000.
Claim 5
Dependent Claim
36 words
A method according to claim 2 in which polymerization is conducted at a temperature from -70° C to reflux and at least 80% of the beads produced have a diameter of no more than 2 microns.
Claim 6
Dependent Claim
37 words
A method according to claim 1 in which the polymerization is conducted at a temperature of 0° to 70° C with application of 0.05 to 1.0 megarads of radiation to the mixture from a cobalt gamma source.
Claim 7
Dependent Claim
25 words
A method according to claim 2 in which the acrylic monomer is selected from a hydroxy substituted acrylate, an amino substituted acrylate, or mixtures thereof.
Claim 8
Dependent Claim
64 words
A method according to claim 6 in which the monomer is selected from compounds of the formula: ##STR3## where R 1 is hydrogen or lower alkyl of 1-8 carbon atoms, R 2 is alkylene of 1-12 carbon atoms, Z is OH or ##STR4## where R 3 or R 4 are H, lower alkyl of 1-10 carbon atoms or lower alkoxy of 1-10 carbon atoms.
Claim 9
Dependent Claim
18 words
A method according to claim 7 in which the monomer is selected from hydroxyethylmethacrylate, hydroxypropylmethacrylate, dimethylaminoethylmethacrylate and 2-aminoethylmethacrylate.
Claim 10
Dependent Claim
37 words
A method according to claim 6 in which the polymerizable mixture contains 1-35 weight percent based on said acrylic monomer of a comonomer selected from a lower alkyl methacrylate, acrylic acid, methacrylic acid, styrene or vinyl toluene.
Claim 11
Dependent Claim
30 words
A method according to claim 6 in which the cross-linking agent is present in the polymerizable mixture in an amount from 0.1 to 30% and is a liquid polyunsaturated compound.
Claim 12
Dependent Claim
22 words
A method according to claim 10 in which the cross-linking agent is a low molecular weight liquid polyvinyl diene or triene compound.
Claim 13
Dependent Claim
23 words
A method according to claim 11 in which the cross-linking agent is selected from ethylene dimethacrylate, divinyl benzene, trimethylol propane trimethacrylate, and N,N'-methylene-bis-acrylamide.
Claim 14
Dependent Claim
12 words
A method according to claim 7 in which the monomer is hydroxyethylmethacrylate.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-10-12 | 1980-04-12 | 1980-10-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-10-12 | 1984-04-12 | 1984-10-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-10-12 | 1988-04-12 | 1988-10-12 | $7700.00 | Window Closed / Lapsed |