US4104208A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for preparation of hard and porous polyvinylalcohol gels
Assignee: Tosoh Corp
•
Filing: 1976-12-01
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Granted: 1978-08-01
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Expires: 1996-12-01
Abstract
Abstract A process for the preparation of hard and porous polyvinylalcohol gels for aqueous gel permeation chromatography, comprises suspension-polymerizing vinyl acetate with diethylene glycol dimethacrylate or glycidyl methacrylate in the presence of a diluent which controls pore size of the product as a crosslinking agent, saponifying the resulting porous polyvinyl acetate gel with an alkali, and subjecting the resulting porous polyvinylalcohol gel to post-crosslinking with epichlorohydrin.
Inventors
- 👤 Shiro Kido
- 👤 Yuji Saito
- 👤 Toshinao Iwaeda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 12:52
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/281; B01J20/291; C; C08; C08J; C08J9/00; C08J9/28; B01J2220/00; B01J2220/50; B01J2220/54; C08J2357/00
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
137 words
A process for the preparation of hard and porous polyvinyl alcohol gels for aqueous gel permeation chromatography, which comprises: suspension-polymerizing a mixture of vinyl acetate and at least one crosslinking agent selected from the group consisting of diethylene glycol dimethacrylate and glycidyl methacrylate, in the presence of a diluent, wherein the weight ratio of the amount of said diluent to the amount of said mixture of vinyl acetate and crosslinking agent is in the range of from 50 : 100 to 250 : 100, and the weight ratio of the amount of said vinyl acetate to the amount of said crosslinking agent is in the range of from 90 : 10 to 30 : 70. saponifying the resulting porous polyvinyl acetate gel with an alkali; and subjecting the resulting porous polyvinyl alcohol gel to postcrosslinking with epichlorohydrin.
Claim 2
Dependent Claim
137 words
A process for the preparation of hard and porous polyvinyl alcohol gels for aqueous gel permeation chromatography, which comprises: suspension-polymerizing a mixture of vinyl acetate and at least one crosslinking agent selected from the group consisting of diethylene glycol dimethacrylate and glycidyl methacrylate, in the presence of a diluent, wherein the weight ratio of the amount of said diluent to the amount of said mixture of vinyl acetate and crosslinking agent is in the range of from 50 : 100 to 250 : 100, and the weight ratio of the amount of said vinyl acetate to the amount of said crosslinking agent is in the range of from 90 : 10 to 30 : 70. saponifying the resulting porous polyvinyl acetate gel with an alkali; and subjecting the resulting porous polyvinyl alcohol gel to postcrosslinking with epichlorohydrin.
Claim 3
Dependent Claim
24 words
The process of claim 1 wherein said diluent is a member selected from the group consisting of isoamyl alcohol, toluene, nitromethane and n-amyl alcohol.
Claim 4
Dependent Claim
26 words
The process of claim 1 wherein the amount of epichlorohydrin is 2 to 20% by weight based on the amount of polyvinylalcohol produced by the saponification.
Claim 5
Dependent Claim
12 words
The hard, porous polyvinylalcohol gel prepared by the process of claim 1.
References Cited (Backward Citations)
US3640734A
Cited
US3896092A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-07-31 | 1982-01-30 | 1982-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-07-31 | 1986-01-30 | 1986-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-07-31 | 1990-01-30 | 1990-08-01 | $7700.00 | Window Closed / Lapsed |