US3948841A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing transparent gels with improved mechanical and sorption properties from copolymers of 2-hydroxyethyl methacrylate and amides of acrylic or methacrylic acid
Assignee: Individual
•
Filing: 1974-05-09
•
Granted: 1976-04-06
•
Expires: 1994-05-09
Abstract
Abstract A process for producing transparent hydrophilic gels having improved mechanical and sorption properties made from copolymers of 2-hydroxyethyl methacrylate and amides of methacrylic or acrylic acid, wherein said 2-hydroxyethyl methacrylate is copolymerized with about 20 to 90 weight percent of said methacrylamide or about 20 to 80 weight percent of said acrylamide in the presence of a crosslinking agent and a diluent, and the gels thus obtained are further modified by heating in an aqueous medium.
Inventors
- 👤 Karel Dusek
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 19:09
CPC Classifications
C; C08; C08F; C08F220/00; C08F220/02; C08F220/52; C08F220/54; C08F220/56; C08F220/10; C08F220/20; Y; Y10; Y10S; Y10S524/00; Y10S524/916
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
186 words
A process for producing transparent hydrophylic gels having improved mechanical and sorption properties made from copolymers of 2-hydroxyethyl methacrylate and amides of methacrylic or acrylic acid, comprising copolymerizing 2-hydroxyethyl methacrylate with about 20 to about 90 weight percent of methacrylamide or about 20 to about 80 weight percent of acrylamide in the presence of about 0.01 to 10% of a crosslinking agent selected from the group consisting of esters of methacrylic and acrylic acids with C 1-4 alkylene glycols; poly (C 1-4 ) alkylene glycols; polyols; glycerine; N,N'-alkylene-bis-acrylamides and methacrylamides; tri-acryloyl-triazine and divinyl sulphone and compatible mixtures thereof and up to about 80% of a diluent selected from the group consisting of glycols, polyglycols and aqeuous mixtures thereof; C 1-4 mono- and dicarboxylic acids; C 1-3 aliphatic alcohols and aqueous mixtures thereof; formamide, dimethylformamide and aqueous mixtures thereof; aqueous solutions of mono-di- and trivalent methal perchlorates; nitrates; bromides; organic acid salts; C 3-6 glycol ethers; C 3-6 alcohols; C 3-6 ketones; aromatic acids; and some heavy metal chlorides and subsequently heating of said gels in an aqueous medium having a pH of between 0.5 and 8.
Claim 2
Dependent Claim
186 words
A process for producing transparent hydrophylic gels having improved mechanical and sorption properties made from copolymers of 2-hydroxyethyl methacrylate and amides of methacrylic or acrylic acid, comprising copolymerizing 2-hydroxyethyl methacrylate with about 20 to about 90 weight percent of methacrylamide or about 20 to about 80 weight percent of acrylamide in the presence of about 0.01 to 10% of a crosslinking agent selected from the group consisting of esters of methacrylic and acrylic acids with C 1-4 alkylene glycols; poly (C 1-4 ) alkylene glycols; polyols; glycerine; N,N'-alkylene-bis-acrylamides and methacrylamides; tri-acryloyl-triazine and divinyl sulphone and compatible mixtures thereof and up to about 80% of a diluent selected from the group consisting of glycols, polyglycols and aqeuous mixtures thereof; C 1-4 mono- and dicarboxylic acids; C 1-3 aliphatic alcohols and aqueous mixtures thereof; formamide, dimethylformamide and aqueous mixtures thereof; aqueous solutions of mono-di- and trivalent methal perchlorates; nitrates; bromides; organic acid salts; C 3-6 glycol ethers; C 3-6 alcohols; C 3-6 ketones; aromatic acids; and some heavy metal chlorides and subsequently heating of said gels in an aqueous medium having a pH of between 0.5 and 8.
Claim 3
Dependent Claim
34 words
A process as defined in claim 1 wherein said methacrylamide is present in amounts of about 25 to about 75% and said acrylamide is present in amounts of about 20 to 50% by weight.
Claim 4
Dependent Claim
17 words
A process as defined in claim 1 wherein the heating is carried out in an aqueous medium.
Claim 5
Dependent Claim
25 words
A process as defined in claim 3 wherein said aqueous medium is a solution of electrolytes having a pH of about 0.5 to about 8.0.
Claim 6
Dependent Claim
24 words
A process as defined in claim 1 further comprising adding a third monomer selected from the group consisting of non-polar vinyl and/or acrylic monomers.
Claim 7
Dependent Claim
43 words
A process as defined in claim 5 wherein said non-polar monomer is selected from the group consisting of styrene, C 1-4 alkyl substituted styrenes, C 1-12 alkyl esters of acrylic and methacrylic acid; C 2-6 alkyl vinyl ethers and C 1-12 vinyl esters.
Claim 8
Dependent Claim
22 words
A process as defined in claim 5 wherein said third monomer is included in amounts of about 3 to 40% by weight.
Claim 9
Dependent Claim
21 words
A process as defined in claim 5, wherein said heating is carried out at a temperature of about 60° to 120°C.
Claim 10
Dependent Claim
12 words
A process as defined in claim 1 wherein said diluent is water.
Claim 11
Dependent Claim
28 words
A process as defined in claim 1 wherein compounds which homogeneously dissolve all of the monomers and are miscible with water are used in the polymerization as diluent.
Claim 12
Dependent Claim
19 words
A transparent hydrophilic gel having improved mechanical and sorption properties produced by the process as defined in claim 1.
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) | 1979-04-06 | 1979-10-06 | 1980-04-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-04-06 | 1983-10-06 | 1984-04-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-04-06 | 1987-10-06 | 1988-04-06 | $7700.00 | Window Closed / Lapsed |