US4176223A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polyimide-esters and filaments prepared from 4-(4'-carboxyphthalimido)benzoic acid or 4-(4'-hydroxyphthalimido)phenol
Assignee: EIDP Inc
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Filing: 1978-12-18
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Granted: 1979-11-27
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Expires: 1998-12-18
Abstract
Abstract High modulus filaments are melt-spun from polyimide-esters derived from 2,6-naphthalene dicarboxylic acid and either a substituted diphenol and 4-(4'-carboxyphthalimido)benzoic acid or terephthalic acid and 4-(4'-hydroxyphthalimido)phenol. The polyimide esters are optically anisotropic in the melt. As-spun filaments from these polymers can be heat treated while free from tension to increase their tenacity.
Inventors
- 👤 Robert S. Irwin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 03:33
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/16; D; D01; D01F; D01F6/00; D01F6/58; D01F6/62
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
125 words
A filament-forming polyimide-ester consisting essentially of units having the structural formulas ##STR26## such that when X is ##STR27## Y is --O--; R is Cl or 1 to 2 carbon alkyl; unit III is present in an amount of from 5-20 mole percent based on the total number of moles of units; and the sum of moles of units II and III is substantially equal to the number of moles of unit I; and when X is --O--; Y is ##STR28## R is H; unit III is present in an amount of from 5-20 mole percent based on the total number of moles of units; and the sum of moles of units I and III is substantially equal to the number of moles of unit II.
Claim 2
Dependent Claim
125 words
A filament-forming polyimide-ester consisting essentially of units having the structural formulas ##STR26## such that when X is ##STR27## Y is --O--; R is Cl or 1 to 2 carbon alkyl; unit III is present in an amount of from 5-20 mole percent based on the total number of moles of units; and the sum of moles of units II and III is substantially equal to the number of moles of unit I; and when X is --O--; Y is ##STR28## R is H; unit III is present in an amount of from 5-20 mole percent based on the total number of moles of units; and the sum of moles of units I and III is substantially equal to the number of moles of unit II.
Claim 3
Dependent Claim
16 words
The polymer of claim 1 wherein X is ##STR29## Y is --O--; and R is methyl.
Claim 4
Dependent Claim
16 words
The polymer of claim 1 wherein X is ##STR30## Y is --O--; and R is Cl.
Claim 5
Dependent Claim
16 words
The polymer of claim 1 wherein X is --O--; Y is ##STR31## and R is hydrogen.
Claim 6
Dependent Claim
17 words
A filament of a polymer according to claim 1 having a modulus of at least 177 dN/tex.
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) | 1982-11-26 | 1983-05-28 | 1983-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-11-26 | 1987-05-28 | 1987-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-11-26 | 1991-05-28 | 1991-11-27 | $7700.00 | Window Closed / Lapsed |