US4864015A
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Method for making thianthrene dianhydride and polyimides obtained therefrom
Assignee: SABIC Global Technologies BV
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Filing: 1988-11-21
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Granted: 1989-09-05
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Expires: 2008-11-21
Abstract
Abstract A method is provided for making 9,10-dithiaanthracene-2,3,6,7-tetracarboxylic acid dianhydride. Polyimides having improved oxidative stability also are provided which can be made intercondensing organic diamine and the aforementioned dianhydride or a dianhydride mixture.
Inventors
- 👤 James A. Cella
- 👤 Deborah A. Haitko
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 14:57
CPC Classifications
C; C07; C07D; C07D495/00; C07D495/12; C07D495/14; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1057; C08G73/1064; C08G73/1085; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31721
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
48 words
Polyimides comprising chemically combined units of the formula, ##STR8## where R and R 1 are selected from C.sub.(1-8) alkyl radicals, C.sub.(1-8) alkoxy radicals and C.sub.(6-14) aryl radicals, R 2 is a C.sub.(6-30) divalent, aromatic organic radical, and a and b are whole numbers equal to 0 or 1.
Claim 2
Dependent Claim
48 words
Polyimides comprising chemically combined units of the formula, ##STR8## where R and R 1 are selected from C.sub.(1-8) alkyl radicals, C.sub.(1-8) alkoxy radicals and C.sub.(6-14) aryl radicals, R 2 is a C.sub.(6-30) divalent, aromatic organic radical, and a and b are whole numbers equal to 0 or 1.
Claim 3
Dependent Claim
12 words
A polyimide in accordance with claim 1, where R 2 is ##STR9##
Claim 4
Dependent Claim
12 words
A polyimide in accordance with claim 1, where R 2 is ##STR10##
Claim 5
Dependent Claim
21 words
Polyimides resulting from the intercondensation of substantially equal molar amounts of aryldiamine and a mixture of thianthrene dianhydride and another dianhydride.
Claim 6
Dependent Claim
21 words
Polyimides resulting from the intercondensation of substantially equal molar amounts of aryldiamine and a mixture of thianthrene dianhydride and another dianhydride.
Claim 7
Dependent Claim
14 words
A polyimide in accordance with claim 4, where the other dianhydride is phthalic anhydride.
Claim 8
Dependent Claim
14 words
A polyimide in accordance with claim 4, where the other dianhydride is pyromellitic dianhydride.
Claim 9
Dependent Claim
14 words
A polyimide in accordance with claim 4, where the other dianhydride is benzophenone dianhydride.
Claim 10
Dependent Claim
15 words
A polyimide in accordance with claim 4, where the other dianhydride is oxydiphthalic acid anhydride.
Claim 11
Dependent Claim
16 words
A polyimide in accordance with claim 4, where the other dianhydride is sulfur diphthalic acid anhydride.
Claim 12
Dependent Claim
14 words
A polyimide in accordance with claim 4, where the other dianhydride is hydroquinone dianhydride.
Claim 13
Dependent Claim
14 words
A polyimide in accordance with claim 4, where the other dianhydride is bisphenol-A dianhydride.
Claim 14
Dependent Claim
14 words
A polyimide in accordance with claim 4, where the other dianhydride is biphenol dianhydride.
Claim 15
Dependent Claim
57 words
A composite comprising carbon fiber and polyimide consisting essentially of chemically combined units of the formula, ##STR11## where R and R 1 are selected form C.sub.(1-8) alkyl radicals, C.sub.(1-8) alkoxy radicals and C.sub.(6-14) aryl radicals, R 2 is a C.sub.(6-30) divalent, aromatic organic radical, and a and b are whole n umbers equal to 0 or 1.
Claim 16
Dependent Claim
57 words
A composite comprising carbon fiber and polyimide consisting essentially of chemically combined units of the formula, ##STR11## where R and R 1 are selected form C.sub.(1-8) alkyl radicals, C.sub.(1-8) alkoxy radicals and C.sub.(6-14) aryl radicals, R 2 is a C.sub.(6-30) divalent, aromatic organic radical, and a and b are whole n umbers equal to 0 or 1.
Claim 17
Dependent Claim
83 words
The polyamic acid intercondensation reaction product of substantially equal molar amounts of organic diamine of the formula, NH.sub.2 R.sup.2 NH.sub.2, and a dianhydride selected from the class consisting of thianthrene dianhydride of the formula, ##STR12## and a mixture of thianthrene dianhydride and another dianhydride, where R and R 1 are selected from C.sub.(1-8) alkyl radicals, C.sub.(1-8) alkoxy radicals and C.sub.(6-14) aryl radicals, R 2 is a C.sub.(6-30) divalent, aromatic organic radical, and a and b are whole numbers equal to 0 or 1.
Claim 18
Dependent Claim
83 words
The polyamic acid intercondensation reaction product of substantially equal molar amounts of organic diamine of the formula, NH.sub.2 R.sup.2 NH.sub.2, and a dianhydride selected from the class consisting of thianthrene dianhydride of the formula, ##STR12## and a mixture of thianthrene dianhydride and another dianhydride, where R and R 1 are selected from C.sub.(1-8) alkyl radicals, C.sub.(1-8) alkoxy radicals and C.sub.(6-14) aryl radicals, R 2 is a C.sub.(6-30) divalent, aromatic organic radical, and a and b are whole numbers equal to 0 or 1.
References Cited (Backward Citations)
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