Patent US4898913A successfully refreshed from Google Patents.
US4898913A
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Method of making hydrophobic copolymers hydrophilic
Assignee: Catalent Pharma Solutions LLC
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Filing: 1989-04-07
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Granted: 1990-02-06
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Expires: 2009-04-07
Abstract
Abstract A method for altering a macroporous cross-linked hydrophobic copolymeric lattice produced by precipitation polymerization in a solvent of at least one monounsaturated ester monomer and at least one polyunsaturated ester monomer soluble therein, in order to render the hydrophobic copolymeric lattice hydrophilic. The method involves saponifying the hydrophobic copolymeric lattice by reacting the surface of the hydrophobic copolymeric lattice with an aqueous alkali. The surface can also be rendered hydrophilic by polymerizing an acrylate monomer onto the lattice in order to form a surface containing carboxylic acid sites. The carboxylic acid sites formed on the surface of the lattice are converted to carboxylate anions.
Inventors
- 👤 Maris J. Ziemelis
- 👤 William R. R. Park
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 20:27
CPC Classifications
C; C08; C08F; C08F265/00; C08F265/04; C08F265/06; C08F8/00; C08F8/44; Y; Y10; Y10S; Y10S525/00; Y10S525/902
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
67 words
A method for altering a macroporous highly cross-linked hydrophobic copolymer, produced by precipitation polymerization in a solvent of at least one monounsaturated ester monomer and at least one polyunsaturated ester monomer soluble therein, in order to render the hydrophobic copolymer hydrophilic, comprising polymerizing an acrylate monomer on the surface of the hydrophobic copolymer in order to form carboxylic acid sites on the surface of the hydrophobic copolymer.
Claim 2
Independent Claim
67 words
A method for altering a macroporous highly cross-linked hydrophobic copolymer, produced by precipitation polymerization in a solvent of at least one monounsaturated ester monomer and at least one polyunsaturated ester monomer soluble therein, in order to render the hydrophobic copolymer hydrophilic, comprising polymerizing an acrylate monomer on the surface of the hydrophobic copolymer in order to form carboxylic acid sites on the surface of the hydrophobic copolymer.
Claim 3
Dependent Claim
24 words
The method of claim 1 including the step of converting the carboxylic acid sites formed on the surface of the copolymer to carboxylate anions.
Claim 4
Dependent Claim
21 words
The method of claim 2 wherein the acrylate monomer is selected from the group consisting of acrylic acid and methacrylic acid.
Claim 5
Dependent Claim
28 words
The method of claim 2 wherein the carboxylic acid sites are converted to carboxylate anions by reacting the surface containing the carboxylic acid sites with an aqueous alkali.
Claim 6
Dependent Claim
24 words
The method of claim 4 wherein the aqueous alkali is selected from the group consisting of sodium hydroxide, potassium hydroxide, and quaternary ammonium hydroxides.
Claim 7
Dependent Claim
12 words
The process of claim 5 wherein the monounsaturated monomer is lauryl methacrylate.
Claim 8
Dependent Claim
13 words
The process of claim 6 wherein the polyunsaturated monomer is ethylene glycol dimethacrylate.
Claim 9
Dependent Claim
11 words
The process of claim 7 wherein the solvent is isopropyl alcohol.
Claim 10
Dependent Claim
84 words
The process of claim 1 in which the copolymer is in the form of a powder, the powder being a combined system of particles, the system of powder particles including unit particles of less than about one micron in average diameter, agglomerates of fused unit particles of sizes in the range of about twenty to eighty microns in average diameter, and aggregates of clusters of fused agglomerates of sizes in the range of about two hundred to about twelve hundred microns in average diameter.
Claim 11
Dependent Claim
16 words
The process of claim 9 wherein the copolymer is formed of a highly cross-linked polymethacrylate copolymer.
Claim 12
Independent Claim
74 words
A method for altering the surface of a macroporous cross-linked hydrophobic copolymer comprising producing a macroporous highly cross-linked hydrophobic copolymer by precipitation polymerization in a solvent of at least one monounsaturated ester monomer and at least one polyunsaturated ester monomer soluble therein, and polymerizing an acrylate monomer on the surface of the hydrophobic copolymer to form carboxylic acid sites on the surface of the hydrophobic copolymer, in order to render the hydrophobic copolymer hydrophilic.
Claim 13
Independent Claim
74 words
A method for altering the surface of a macroporous cross-linked hydrophobic copolymer comprising producing a macroporous highly cross-linked hydrophobic copolymer by precipitation polymerization in a solvent of at least one monounsaturated ester monomer and at least one polyunsaturated ester monomer soluble therein, and polymerizing an acrylate monomer on the surface of the hydrophobic copolymer to form carboxylic acid sites on the surface of the hydrophobic copolymer, in order to render the hydrophobic copolymer hydrophilic.
References Cited (Backward Citations)
US27026A
Cited
US2809943A
Cited
US3637535A
Cited
US4224415A
Cited
US4224415B1
Cited
US3509078A
Cited
US3418262A
Cited
US3627708A
Cited
US3767600A
Cited
USRE27026E
Cited
US3892822A
Cited
US3989649A
Cited
DE2608533A1
Cited
US4208309A
Cited
CA1168157A
Cited
US4724240A
Cited
US4661327A
Cited
US4690825A
Cited
EP0252463A2
Cited
WO1988001164A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-02-05 | 1993-08-07 | 1994-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-05 | 1997-08-07 | 1998-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-05 | 2001-08-07 | 2002-02-06 | $7700.00 | Window Closed / Lapsed |