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Patent US4593064A successfully refreshed from Google Patents.
US4593064A
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Method for polymerizing methyl methacrylate
Assignee: Roehm GmbH Darmstadt
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Filing: 1985-05-03
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Granted: 1986-06-03
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Expires: 2005-05-03
Abstract
Abstract What is disclosed are a method for the polymerization of methyl methacrylate or a monomer mixture predominantly comprising methyl methacrylate, which comprises polymerizing in the presence of a free radical-forming initiator and in the presence of a sterically hindered amine containing at least one group having the formula <IMAGE> wherein R is the same or different alkyl, R' is hydrogen or alkyl, and A is a 2- or 3-membered alkylene chain which may be bound to a further organic group, polymer sheets prepared by such a method, and the use of such sheets in solaria.
Inventors
- 👤 Ludwig Hosch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:09
CPC Classifications
C; C08; C08F; C08F20/00; C08F20/02; C08F20/10; C08F20/12; C08F20/14; C08F2/00; C08F2/44
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
91 words
A method for making a methyl methacrylate polymer having high resistance to ultraviolet radiation and thermal damage, which method comprises polymerizing methyl methacrylate or a monomer mixture comprising at least 80 percent by weight of methyl methacrylate in the presence of a free radical-forming initiator and in the presence of 0.01 to 1 percent, by weight of the methyl methacrylate or monomer mixture, of a sterically hindered amine of the formula where n is an integer such that the number average molecular weight of the amine is somewhat greater than 3000.
Claim 2
Independent Claim
91 words
A method for making a methyl methacrylate polymer having high resistance to ultraviolet radiation and thermal damage, which method comprises polymerizing methyl methacrylate or a monomer mixture comprising at least 80 percent by weight of methyl methacrylate in the presence of a free radical-forming initiator and in the presence of 0.01 to 1 percent, by weight of the methyl methacrylate or monomer mixture, of a sterically hindered amine of the formula where n is an integer such that the number average molecular weight of the amine is somewhat greater than 3000.
Claim 3
Independent Claim
92 words
A method for making a methyl methacrylate polymer having high resistance to ultraviolet radiation and thermal damage, which method comprises polymerizing methyl methacrylate or a monomer mixture comprising at least 80 percent by weight of methyl methacrylate in the presence of a free radical-forming initiator and in the presence of 0.01 to 1 percent, by weight of the methyl methacrylate or monomer mixture, of a sterically hindered amine of the formula ##STR8## wherein n is an integer such that the number average molecular weight of the amine is somewhat greater than 2500.
Claim 4
Independent Claim
92 words
A method for making a methyl methacrylate polymer having high resistance to ultraviolet radiation and thermal damage, which method comprises polymerizing methyl methacrylate or a monomer mixture comprising at least 80 percent by weight of methyl methacrylate in the presence of a free radical-forming initiator and in the presence of 0.01 to 1 percent, by weight of the methyl methacrylate or monomer mixture, of a sterically hindered amine of the formula ##STR8## wherein n is an integer such that the number average molecular weight of the amine is somewhat greater than 2500.
References Cited (Backward Citations)
US3759881A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-06-02 | 1989-12-02 | 1990-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-06-02 | 1993-12-02 | 1994-06-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-06-02 | 1997-12-02 | 1998-06-03 | $7700.00 | Window Closed / Lapsed |