US4742152A
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High temperature fluorinated polyimides
Assignee: RTX Corp
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Filing: 1986-05-27
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Granted: 1988-05-03
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Expires: 2006-05-27
Abstract
Abstract High temperature fluorinated polyimides having repeating polymer units of the formula ##STR1## wherein X is aromatic or aliphatic. The polyimides can be made by oxidizing 1-phenyl-1,1-bis (3,4-xylyl)-2,2,2-trifluorethane to form 4,4'(2,2,2-trifluoro-1-phenylethylidene)biphthalic tetra carboxylic acid and dehydrating that to form 4,4'(2,2,2-trifluoro-1-phenyl-ethylidene-biphthalic tetra carboxylic acid dianhydride. The dianhydride is polymerized with a diamine to form a polyamic acid which is further imidized to the polyimide. Alternatively, the dianhydride can be esterified to form a 4,4'(2,2,2-trifluoro-1-phenylethylidene)-biphthalic tetracarboxylic acid dialkylester which is then polymerized with a diamine to form a polyamic acid which can then be imidized to a polyimide.
Inventors
- 👤 Daniel A. Scola
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 11:50
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1039
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
19 words
A high temperature fluorinated polyimide having repeating polymer units of the formula ##STR17## wherein X is aromatic or aliphatic.
Claim 2
Dependent Claim
19 words
A high temperature fluorinated polyimide having repeating polymer units of the formula ##STR17## wherein X is aromatic or aliphatic.
Claim 3
Dependent Claim
68 words
The high temperature fluorinated polyimide as recited in claim 1 wherein X represents: a. ortho, meta, or para phenylene or biphenylene optionally substituted with halogen, aryl, alkyl, nitro, sulfonic acid, carboxylic acid, hydroxy, cyano, aryloxy, or alkoxy; or b. ##STR18## where Y is methylene, sulfone, sulfoxide, carbonyl, oxide, sulfide, aromatic or aryloxy; or c. naphthalene, anthracene, phenanthrene, triphenylene or pyrene; or d. pyridine, quinoline, acridine, thiophene or indole.
Claim 4
Dependent Claim
29 words
The polyimide as recited in claim 1 where in X is para-phenylene, 4,4 sulfonyl bis phenylene, 4,4'-methylene bis phenylene, 3,3' hexafluoroisopropylidene bis (phenylene) or 4,4' hexafluoroisopropylidene bis phenoxy phenylene.
Claim 5
Independent Claim
71 words
A method of making a high temperature fluorinated polyimide comprising: a. oxidizing 1-phenyl-1, 1-bis(3,4-xylyl)-2,2,2-trifluorethane to form a tetra acid, 4,4'(2,2,2-trifluoro-1-phenylethylidene) biphthalic tetracarboxylic acid; b. dehydrating said tetra acid to form a dianhydride of 4,4'(2,2,2-trifluoro-1-phenylethylidene) biphthalic tetracarboxylic acid; c. esterifying said dianhydride to form a diester 4,4'(2,2,2-trifluoro-1-phenylethylidene)-biphthalic tetracarboxylic acid dialkylester; d. polymerizing said diester with a diamine to form a polyamic acid; and e. imidizing said polyamic acid to form a polyimide.
Claim 6
Independent Claim
71 words
A method of making a high temperature fluorinated polyimide comprising: a. oxidizing 1-phenyl-1, 1-bis(3,4-xylyl)-2,2,2-trifluorethane to form a tetra acid, 4,4'(2,2,2-trifluoro-1-phenylethylidene) biphthalic tetracarboxylic acid; b. dehydrating said tetra acid to form a dianhydride of 4,4'(2,2,2-trifluoro-1-phenylethylidene) biphthalic tetracarboxylic acid; c. esterifying said dianhydride to form a diester 4,4'(2,2,2-trifluoro-1-phenylethylidene)-biphthalic tetracarboxylic acid dialkylester; d. polymerizing said diester with a diamine to form a polyamic acid; and e. imidizing said polyamic acid to form a polyimide.
Claim 7
Dependent Claim
32 words
The method of making a high temperature fluorinated polyimide as recited in claim 4 wherein said diamine is para-phenylene, 4,4 sulfonylbis (phenylene) 4,4'-methylenebis (phenylene) or 3,3'hexafluoroisopropylidenebis (phenylene) or 4,4' hexafluoroisopropylidenebis (phenoxy phenylene).
Claim 8
Dependent Claim
35 words
The method of making a high temperature fluorinated polyimide as recited in claim 4 wherein said 1-phenyl-1,1-bis(3,4-xylyl)-2,2,2-trifluorethane is oxidized at a temperature below about 250° C. for less than about 1.5 hours with nitric acid.
Claim 9
Dependent Claim
46 words
The method of making a high temperature fluorinated polyimide as recited in claim 4 wherein said tetra acid is dehydrated at about 180° C. to about 240° C. for about 1 hour to about 3 hours under about 1 millimeter to about 30 millimeters of vacuum.
Claim 10
Dependent Claim
26 words
The mthod of making a high temperature fluorinated polyimide as recited in claim 4 wherein said dianhydride is esterified at a temperature below about 40° C.
Claim 11
Dependent Claim
33 words
The method of making a high temperature fluorinated polyimide as recited in claim 4 wherein said polyimide is heated at a temperature less than about 320° C. resulting in a high temperature polyimide.
References Cited (Backward Citations)
US3310573A
Cited
GB1062435A
Cited
US3356648A
Cited
GB1216505A
Cited
US3705870A
Cited
US4063984A
Cited
US4307024A
Cited
US4336175A
Cited
US4569988A
Cited
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