US4298716A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Styrenic tetrapolymer
Assignee: Bayer Antwerpen NV
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Filing: 1980-04-03
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Granted: 1981-11-03
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Expires: 2000-04-03
Abstract
Abstract A tetrapolymer of α-methylstyrene, styrene, maleic anhydride and acrylonitrile is prepared by mass/suspension batch process without the need for staged late addition of monomers. The tetrapolymer is useful as a replacement for SAN as diluent in the preparation of ABS-type polymers.
Inventors
- 👤 Daniel L. Dufour
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:36
CPC Classifications
C; C08; C08L; C08L25/00; C08L25/02; C08L25/04; C08L25/08; C08L25/12; C08F; C08F212/00; C08F212/02; C08F212/04; C08F212/06; C08F212/12; C08L25/16; C08L35/00; C08L35/06; C08L55/00; C08L55/02
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
106 words
A process for the production of a thermoformable composition which comprises sequentially: A. forming a reaction mixture comprising styrene, α-methyl styrene, an ethylenically unsaturated nitrile and an ethylenically unsaturated dicarboxylic acid anhydride wherein the weight proportions of the components are such that: (i) styrene+α-methyl styrene represents from 45-60%; (ii) nitrile+anhydride represents from 40-55%; (iii) α-methyl styrene represents from 10-50%; and (iv) nitrile and anhydride each individually represent at least 10% of the monomers present in the reaction mixture; B. initiating and continuing polymerization of the mixture in the absence of a dispersing medium till at least 40% conversion; and C. substantially completing polymerization in aqueous suspension.
Claim 2
Dependent Claim
106 words
A process for the production of a thermoformable composition which comprises sequentially: A. forming a reaction mixture comprising styrene, α-methyl styrene, an ethylenically unsaturated nitrile and an ethylenically unsaturated dicarboxylic acid anhydride wherein the weight proportions of the components are such that: (i) styrene+α-methyl styrene represents from 45-60%; (ii) nitrile+anhydride represents from 40-55%; (iii) α-methyl styrene represents from 10-50%; and (iv) nitrile and anhydride each individually represent at least 10% of the monomers present in the reaction mixture; B. initiating and continuing polymerization of the mixture in the absence of a dispersing medium till at least 40% conversion; and C. substantially completing polymerization in aqueous suspension.
Claim 3
Dependent Claim
44 words
A process according to claim 1 in which, after completion of the polymerization process, the polymer is subjected to a heat treatment above 180° C. to drive off water and reform at least some of the anhydride groups hydrolyzed during the suspension polymerization operation.
Claim 4
Dependent Claim
27 words
A process according to claim 2 in which the polymeric product is blended with a diene rubber grafted with a vinyl-aromatic monomer and an unsaturated nitrile monomer.
References Cited (Backward Citations)
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US3509110A
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US4141934A
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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) | 1984-11-02 | 1985-05-04 | 1985-11-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-11-02 | 1989-05-04 | 1989-11-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-11-02 | 1993-05-04 | 1993-11-03 | $7700.00 | Window Closed / Lapsed |