Patent US4139685A successfully refreshed from Google Patents.
US4139685A
Expired / Lapsed
US
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Method for the preparation of polyacrylimide and polymethacrylimide foams
Assignee: Roehm GmbH Darmstadt
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Filing: 1978-05-31
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Granted: 1979-02-13
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Expires: 1998-05-31
Abstract
Abstract What is disclosed is a method of making a foamed polyacrylimide or polymethacrylimide polymer which comprises free-radically polymerizing a mixture comprising (A) a member selected from a first group consisting of acrylonitrile and methacrylonitrile and a member selected from a second group consisting of acrylic acid and methacrylic acid, the mol ratio of the members of said first group to the members of said second group being between 2:3 and 3:2, and (B) up to 20 percent, by weight of (A), of other free radically-polymerizable monomers copolymerizable therewith, Said mixture further comprising from 1 to 15 percent, by weight of (A) and (B), of a foaming agent which is a monovalent aliphatic alcohol having 3 to 8 carbon atoms, to form a solid polymer, and then heating said polymer at a temperature from 170° C. to 250° C. until a foam is formed.
Inventors
- 👤 Guenter Schroeder
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 07:07
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/04; C08J9/12; C08J9/14; C08J9/142; C08J5/00; C08J5/12; C08J2333/00; C08J2333/24; C08J2333/26; Y; Y10; Y10T; Y10T428/00; Y10T428/249921; Y10T428/249953; Y10T428/249987; Y10T428/249991; Y10T428/249992
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
139 words
The method of making a foamed polyacrylimide or polymethacrylimide polymer which comprises free-radically polymerizing a mixture comprising (A) a member selected from a first group consisting of acrylonitrile and methacrylonitrile and a member selected from a second group consisting of acrylic acid and methacrylic acid, the mol ratio of the members of said first group to the members of said second group being between 2:3 and 3:2, and (B) up to 20 percent, by weight of (A), of other free radically-polymerizable monomers copolymerizable therewith, said mixture further comprising from 1 to 15 percent, by weight of (A) and (B), of a foaming agent which is a monovalent aliphatic alcohol having 3 to 8 carbon atoms, to form a solid polymer, and then heating said polymer at a temperature from 170° C. to 250° C. until a foam is formed.
Claim 2
Independent Claim
139 words
The method of making a foamed polyacrylimide or polymethacrylimide polymer which comprises free-radically polymerizing a mixture comprising (A) a member selected from a first group consisting of acrylonitrile and methacrylonitrile and a member selected from a second group consisting of acrylic acid and methacrylic acid, the mol ratio of the members of said first group to the members of said second group being between 2:3 and 3:2, and (B) up to 20 percent, by weight of (A), of other free radically-polymerizable monomers copolymerizable therewith, said mixture further comprising from 1 to 15 percent, by weight of (A) and (B), of a foaming agent which is a monovalent aliphatic alcohol having 3 to 8 carbon atoms, to form a solid polymer, and then heating said polymer at a temperature from 170° C. to 250° C. until a foam is formed.
Claim 3
Dependent Claim
16 words
A method as in claim 1 wherein said aliphatic alcohol is a secondary or tertiary alcohol.
Claim 4
Dependent Claim
13 words
A method as in claim 2 wherein said aliphatic alcohol is tert.-butyl alcohol.
Claim 5
Dependent Claim
28 words
A method as in claim 1 wherein said mixture additionally comprises from 0.1 to 3 percent of water, by weight of the total weight of the reaction mixture.
Claim 6
Dependent Claim
14 words
A method as in claim 1 wherein (A) consists of methacrylonitrile and methacrylic acid.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-02-12 | 1982-08-14 | 1983-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-02-12 | 1986-08-14 | 1987-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-02-12 | 1990-08-14 | 1991-02-13 | $7700.00 | Window Closed / Lapsed |