US5071997A
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US
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Polyimides comprising substituted benzidines
Assignee: AKRON 302 E BUCHTEL AVE AKRON OH 44325, University of
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Filing: 1989-07-20
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Granted: 1991-12-10
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Expires: 2009-07-20
Abstract
Abstract A new class of polyimides and copolyimides made from substituted benzidines and aromatic dianhydrides and other aromatic diamines. The polyimides obtained with said diamines are distinguished by excellent thermal, excellent solubility, excellent electrical properties such as very low dielectric constants, excellent clarity and mechanical properties making the polyimides ideally suited as coating materials for microelectronic apparatii, as membranes for selective molecular or gas separation, as fibers in molecular composites, as high tensile strength, high compression strength fibers, as film castable coatings, or as fabric components.
Inventors
- 👤 Frank W. Harris
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:43
CPC Classifications
B; B01; B01D; B01D71/00; B01D71/06; B01D71/58; B01D71/62; B01D71/64; C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1039; C08G73/1042; C08G73/1057; C08G73/1064; C08G73/1067; C08G73/1071; Y; Y10; Y10T; Y10T428/00; Y10T428/29; Y10T428/2913; Y10T428/2933; Y10T428/2964; Y10T428/2967; Y10T428/2969; Y10T428/31504; Y10T428/31721
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
46 words
A polyimide which consists of 1 to 100 mole percent of the structural elements of the formula (II) ##STR10## where R is a tetravalent organic radical, each A is selected from the group consisting of a halogenated alkyl group, an aryl group and a substituted-aryl group.
Claim 2
Dependent Claim
46 words
A polyimide which consists of 1 to 100 mole percent of the structural elements of the formula (II) ##STR10## where R is a tetravalent organic radical, each A is selected from the group consisting of a halogenated alkyl group, an aryl group and a substituted-aryl group.
Claim 3
Dependent Claim
13 words
A polyimide according to claim 1 wherein A is a halogenated alkyl group.
Claim 4
Dependent Claim
13 words
A polyimide according to claim 2 wherein said halogenated alkyl group is trifluoromethyl.
Claim 5
Dependent Claim
19 words
A polyimide according to claim 1 wherein said polymer consists of 100 mole percent of repeat unit formula (II).
Claim 6
Dependent Claim
13 words
A polyimide according to claim 4 wherein A is a halogenated alkyl group.
Claim 7
Dependent Claim
13 words
A polyimide according to claim 5 wherein said halogenated alkyl group is trifluoromethyl.
Claim 8
Dependent Claim
47 words
A polyimide according to claim 1 wherein said polyimide is characterized by complete solubility in m-cresol or NMP, by UV transparency from about 65% to about 100% at 375 nm, and by a 5% weight loss at a temperature from about 500° C. to about 600° C.
Claim 9
Dependent Claim
57 words
A polyimide according to claim 4 wherein said polyimide is characterized by complete solubility in m-cresol or NMP, by UV transparency from about 65% to about 100% at 375 nm, by low dielectric constant, and by excellent thermal stability as evidenced by a 5% weight loss at a temperature from about 500° C. to about 600° C.
Claim 10
Dependent Claim
66 words
A polyimide of claim 1 characterized by the ability to be drawn to form fibers of high tensile strength, excellent resistance to fibrillation, high compressive strength and high temperature stability, said fiber being oriented in at least one direction by being drawn at least two times and being crystalline in the drawing direction and partially or wholly non-crystalline in the direction perpendicular to the drawing direction.
Claim 11
Dependent Claim
94 words
A film formed from a polyimide consisting of 1 to 100 mole percent of repeat units of formula (II) ##STR11## where R is a tetravalent organic radical, each A is selected from the group consisting of a halogenated alkyl group, an aryl group and a substituted-aryl group, said polyimide characterized by complete solubility in m-cresol, by UV transparency from about 65% to about 100% at 375 nm, a low dielectric constant, and by excellent thermal stability as evidenced by a 5% weight loss at a temperature from about 500° C. to about 600° C.
Claim 12
Dependent Claim
94 words
A film formed from a polyimide consisting of 1 to 100 mole percent of repeat units of formula (II) ##STR11## where R is a tetravalent organic radical, each A is selected from the group consisting of a halogenated alkyl group, an aryl group and a substituted-aryl group, said polyimide characterized by complete solubility in m-cresol, by UV transparency from about 65% to about 100% at 375 nm, a low dielectric constant, and by excellent thermal stability as evidenced by a 5% weight loss at a temperature from about 500° C. to about 600° C.
Claim 13
Dependent Claim
13 words
A polyimide according to claim 10 wherein A is a halogenated alkyl group.
Claim 14
Dependent Claim
13 words
A polyimide according to claim 69 wherein said halogenated alkyl group is trifluoromethyl.
Claim 15
Dependent Claim
19 words
A polyimide according to claim 10 wherein said polymer consists of 100 mole percent of percent unit formula (II).
Claim 16
Dependent Claim
13 words
A polyimide according to claim 13 wherein A is a halogenated alkyl group.
Claim 17
Dependent Claim
13 words
A polyimide according to claim 14 wherein said halogenated alkyl group is trifluoromethyl.
Claim 18
Dependent Claim
147 words
A fiber formed from a polyimide consisting of 1 to 100 mole percent of repeat units of formula (II) ##STR12## where R is a tetravalent organic radical, each A is selected from the group consisting of a halogenated alkyl group, an aryl group and a substituted-aryl group, said polyimide characterized by complete solubility in m-cresol, by UV transparency from about 65% to about 100% at 375 nm, a low dielectric constant, and by excellent thermal stability as evidenced by a 5% weight loss at a temperature from about 500° C. to about 600° C., said fiber oriented in one direction by being drawn at least two times in said direction and being characterized by high tensile strength in the draw direction, excellent resistance to fibrillation, a high degree of crystallinity in the drawing direction and partially or entirely non-crystalline in a direction perpendicular to the drawing direction.
Claim 19
Dependent Claim
147 words
A fiber formed from a polyimide consisting of 1 to 100 mole percent of repeat units of formula (II) ##STR12## where R is a tetravalent organic radical, each A is selected from the group consisting of a halogenated alkyl group, an aryl group and a substituted-aryl group, said polyimide characterized by complete solubility in m-cresol, by UV transparency from about 65% to about 100% at 375 nm, a low dielectric constant, and by excellent thermal stability as evidenced by a 5% weight loss at a temperature from about 500° C. to about 600° C., said fiber oriented in one direction by being drawn at least two times in said direction and being characterized by high tensile strength in the draw direction, excellent resistance to fibrillation, a high degree of crystallinity in the drawing direction and partially or entirely non-crystalline in a direction perpendicular to the drawing direction.
Claim 20
Dependent Claim
13 words
A polyimide according to claim 16 wherein A is a halogenated alkyl group.
Claim 21
Dependent Claim
13 words
A polyimide according to claim 17 wherein said halogenated alkyl group is trifluoromethyl.
Claim 22
Dependent Claim
19 words
A polyimide according to claim 16 wherein said polymer consists of 100 mole percent of repeat unit formula (II).
Claim 23
Dependent Claim
13 words
A polyimide according to claim 19 wherein A is a halogenated alkyl group.
Claim 24
Dependent Claim
13 words
A polyimide according to claim 20 wherein said halogenated alkyl group is trifluoromethyl.
Claim 25
Dependent Claim
151 words
An elastomeric or resinous fiber composite comprising fibers of a polyimide consisting of 1 to 100 mole percent of repeat units of formula (II) ##STR13## where R is a tetravalent organic radical, each A is selected from the group consisting of a halogenated alkyl group, an aryl group and a substituted-aryl group, said polyimide characterized by complete solubility in m-cresol, by UV transparency from about 65% to about 100% at 375 nm, a low dielectric constant, and excellent thermal stability as evidenced by a 5% weight loss at a temperature from about 500° C. to about 600° C., said fiber oriented in one direction by being drawn at least two times in said direction and being characterized by high tensile strength in the draw direction, excellent resistance to fibrillation, a high degrees of crystallinity in the drawing direction and partially or entirely non-crystalline in a direction perpendicular to the drawing direction.
Claim 26
Dependent Claim
151 words
An elastomeric or resinous fiber composite comprising fibers of a polyimide consisting of 1 to 100 mole percent of repeat units of formula (II) ##STR13## where R is a tetravalent organic radical, each A is selected from the group consisting of a halogenated alkyl group, an aryl group and a substituted-aryl group, said polyimide characterized by complete solubility in m-cresol, by UV transparency from about 65% to about 100% at 375 nm, a low dielectric constant, and excellent thermal stability as evidenced by a 5% weight loss at a temperature from about 500° C. to about 600° C., said fiber oriented in one direction by being drawn at least two times in said direction and being characterized by high tensile strength in the draw direction, excellent resistance to fibrillation, a high degrees of crystallinity in the drawing direction and partially or entirely non-crystalline in a direction perpendicular to the drawing direction.
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