US4772671A
Expired / Lapsed
US
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Process for the preparation of a thermoplastic polymer
Assignee: Stamicarbon BV
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Filing: 1986-10-15
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Granted: 1988-09-20
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Expires: 2006-10-15
Abstract
Abstract A process for the preparation of a thermoplastic polymer on the basis of an alkenyl-aromatic monomer and an unsaturated dicarboxylic acid comprises the addition of 10 to 100 ppm relative to the polymer wt. % of an acid during polymerization. Suitable acids that can be applied are carboxylic acids, and sulphur- and /or phosphorus-containing acids or their mixtures.
Inventors
- 👤 Reinard J. M. Steeman
- 👤 Peter J. N. Meyer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 03:56
CPC Classifications
C; C08; C08F; C08F222/00; C08F222/04; C08F222/06; C08F222/08
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
51 words
Process for the preparation of a thermoplastic polymer on the basis of an alkenyl-aromatic monomer and an unsaturated dicarboxylic anhydride, characterized in that the polymerization is effected in the presence of 10-100 ppm of an acid relative to the polymer, wherein a carboxylic acid and/or a sulphur--and/or phosphorus--containing acid is added.
Claim 2
Dependent Claim
51 words
Process for the preparation of a thermoplastic polymer on the basis of an alkenyl-aromatic monomer and an unsaturated dicarboxylic anhydride, characterized in that the polymerization is effected in the presence of 10-100 ppm of an acid relative to the polymer, wherein a carboxylic acid and/or a sulphur--and/or phosphorus--containing acid is added.
Claim 3
Dependent Claim
19 words
Process according to claim 1, characterized in that 30-100 ppm of the acid relative to the polymer is added.
Claim 4
Dependent Claim
24 words
Process according to claim 1, characterized in that acetic acid, citric acid, benzoic acid, oxalic acid, phosphoric acid or paratoluene sulphonic acid is added.
Claim 5
Dependent Claim
16 words
Process according to claim 3, characterized in that phosphoric acid or paratoluene sulphonic acid is added.
Claim 6
Dependent Claim
16 words
Process according to claim 1, characterized in that the alkenyl-aromatic monomer is styrene and/or α-methyl styrene.
Claim 7
Dependent Claim
15 words
Process according to claim 1, characterized in that the unsaturated dicarboxylic anhydride is maleic anhydride.
Claim 8
Dependent Claim
23 words
Process according to claim 1, characterized in that a styrene-maleic anhydride copolymer with 18-50 mol% maleic anhydride and 82-50 mol% styrene is prepared.
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) | 1991-09-20 | 1992-03-21 | 1992-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-09-20 | 1996-03-21 | 1996-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-09-20 | 2000-03-21 | 2000-09-20 | $7700.00 | Window Closed / Lapsed |