US4485207A
Expired / Lapsed
US
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Macroscopic divinylbenzene homogeneous gels and process
Assignee: Massachusetts Institute of Technology
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Filing: 1983-09-19
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Granted: 1984-11-27
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Expires: 2003-09-19
Abstract
Abstract Macroscopic divinylbenzene gels are provided having a high concentration of chemically accessible free vinyl groups. The gels are prepared in a mixture of nonpolar and polar solvents and in the presence of a polymerization initiator under conditions to eliminate syneresis.
Inventors
- 👤 Frank S. Bates
- 👤 Robert E. Cohen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 03:50
CPC Classifications
C; C08; C08F; C08F212/00; C08F212/34; C08F212/36
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
161 words
The process for forming the composition comprising a macroscopic gel network which is insoluble in a solvent, containing at least about 1.4×10 -3 moles chemically accessible free vinyl groups per gram of gel, comprising a polymeric composition obtained by polymerizing a monomer composition selected from the group consisting of divinylbenzene monomer and divinylbenzene copolymerized with an acyclic nonacidic polymerizable monomer which comprises contacting said monomer composition with an anionic polymerization initiator in the presence of a solvent comprising a polar solvent composition, said solvent composition being selected from the group consisting of (a) a nonpolar solvent and a polar solvent comprising tetrahydrofuran, dimethoxyethane or tetramethylethylenediamine, (b) a mixture of dioxane and toluene, (c) a mixture of dioxane and benzene, (d) tetrahydrofuran at a temperature below about -40° C. and (e) dioxane at a temperature above about 30° C., the weight ratio of the soluble composition and the polymerization initiator being regulated to favor linear polymerization while minimizing cross linking and syneresis.
Claim 2
Dependent Claim
161 words
The process for forming the composition comprising a macroscopic gel network which is insoluble in a solvent, containing at least about 1.4×10 -3 moles chemically accessible free vinyl groups per gram of gel, comprising a polymeric composition obtained by polymerizing a monomer composition selected from the group consisting of divinylbenzene monomer and divinylbenzene copolymerized with an acyclic nonacidic polymerizable monomer which comprises contacting said monomer composition with an anionic polymerization initiator in the presence of a solvent comprising a polar solvent composition, said solvent composition being selected from the group consisting of (a) a nonpolar solvent and a polar solvent comprising tetrahydrofuran, dimethoxyethane or tetramethylethylenediamine, (b) a mixture of dioxane and toluene, (c) a mixture of dioxane and benzene, (d) tetrahydrofuran at a temperature below about -40° C. and (e) dioxane at a temperature above about 30° C., the weight ratio of the soluble composition and the polymerization initiator being regulated to favor linear polymerization while minimizing cross linking and syneresis.
Claim 3
Dependent Claim
11 words
The process of claim 1 wherein said monomeric composition is divinylbenzene.
Claim 4
Dependent Claim
16 words
The process of claim 1 wherein said monomeric composition is a mixture of divinylbenzene and ethylstyrene.
Claim 5
Dependent Claim
21 words
The process of any one of claims 1, 2 or 3 wherein said solvent comprises a mixture of benzene and tetrahydrofuran.
Claim 6
Dependent Claim
21 words
The process of any one of claims 1, 2 or 3 wherein said solvent comprises a mixture of toluene and dioxane.
Claim 7
Dependent Claim
17 words
The process of any one of claims 1, 2 or 3 wherein said initiator is a butyllithium.
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) | 1987-11-27 | 1988-05-28 | 1988-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-11-27 | 1992-05-28 | 1992-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-11-27 | 1996-05-28 | 1996-11-27 | $7700.00 | Window Closed / Lapsed |