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US4247681A
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Aromatic polyesters of 9,9-bis-(4-hydroxyphenyl)-fluorene, phthalic acids and phosphorus halides
Assignee: Isovolta AG
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Filing: 1979-07-17
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Granted: 1981-01-27
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Expires: 1999-07-17
Abstract
Abstract A process for the preparation of aromatic polyesters which are characterized particularly by high-temperature stability and difficult inflammability and which show, in addition, a low development of heat and a high char yield in combustion.
Inventors
- 👤 Hermann Mark
- 👤 Otto Szabolcs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 16:46
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/68; C08G63/692; C08G63/6924; C08G63/6926
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
116 words
An aromatic polyester composition prepared by the polycondensation of a mixture comprised of (a) a phenol component comprised of 50 to 100% of 9,9-bis-(4-hydroxyphenyl)-fluorene, (b) from about 50 to 92 mol percent, based on the number of moles of component (a), of an acid halide of isophthalic acid and/or terephthalic acid; and (c) from about 8 to 50 mol percent, based on the number of moles of component (a), of one or more compounds of the formula ##STR2## wherein X is a halogen atom and R is a halogen atom or an alkyl or alkoxy radical having from 1 to 6 carbon atoms or an aryl or phenoxy group having from 6 to 8 carbon atoms.
Claim 2
Dependent Claim
116 words
An aromatic polyester composition prepared by the polycondensation of a mixture comprised of (a) a phenol component comprised of 50 to 100% of 9,9-bis-(4-hydroxyphenyl)-fluorene, (b) from about 50 to 92 mol percent, based on the number of moles of component (a), of an acid halide of isophthalic acid and/or terephthalic acid; and (c) from about 8 to 50 mol percent, based on the number of moles of component (a), of one or more compounds of the formula ##STR2## wherein X is a halogen atom and R is a halogen atom or an alkyl or alkoxy radical having from 1 to 6 carbon atoms or an aryl or phenoxy group having from 6 to 8 carbon atoms.
Claim 3
Dependent Claim
18 words
The polyester composition of claim 1 wherein the phenol component is comprised of up to 25% of 2,2-bis-(4-hydroxyphenyl)-propane.
Claim 4
Dependent Claim
17 words
The polyester composition of claim 1 wherein component (b) is comprised of isophthalic chloride and/or terephthalic chloride.
Claim 5
Dependent Claim
22 words
The polyester composition of claim 1 wherein component (c) is comprised of phosphorous oxychloride or phenylphosphine oxide dichloride, or a mixture thereof.
Claim 6
Dependent Claim
31 words
The polyester composition of claim 1 wherein the mixture comprised from about 75 to 90 mol percent of component (b) and from about 10 to 25 mol percent of component (c).
Claim 7
Dependent Claim
39 words
The polyester composition of claim 1 wherein the phosphorous compounds of component (c) are a mixture of such a phosphorous compound with three halogen atoms, and of one or more such phosphorous compounds which contain each two halogen atoms.
Claim 8
Dependent Claim
14 words
The polyester composition of claim 1 wherein each halogen atom is a chlorine atom.
Claim 9
Dependent Claim
13 words
The polyester composition of claim 1 wherein each X is a chlorine atom.
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) | 1984-01-27 | 1984-07-28 | 1985-01-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-01-27 | 1988-07-28 | 1989-01-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-01-27 | 1992-07-28 | 1993-01-27 | $7700.00 | Window Closed / Lapsed |