US3673143A
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Optically anisotropic spinning dopes of polycarbonamides
Assignee: EIDP Inc
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Filing: 1970-06-24
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Granted: 1972-06-27
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Expires: 1990-06-24
Abstract
Abstract Fibers of high molecular weight p-oriented polycarbonamides of recurring units of the formula: WHEREIN Ar1 is p-phenylene and/or chloro-substituted pphenylene, and Ar2 is p-phenylene. These fibers have an initial modulus in excess of 170 gpd. and an orientation angle of up to 40* and/or a sonic velocity of at least about 4 km./sec. either as-extruded or after maintaining the fibers at 0.99 to 1.50 times their as-spun lengths and heating in a zone maintained between 200* and 1,000* C. Optically anisotropic spinning dopes of these polycarbonamides of Formula I units, lithium or calcium chloride and certain amide or urea solvents, are also disclosed.
Inventors
- 👤 Thomas I Bair
- 👤 Paul W Morgan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 13:52
CPC Classifications
C; C08; C08J; C08J3/00; C08J3/02; C08J3/09; C08J3/091; C08J3/096; D; D01; D01F; D01F6/00; D01F6/58; D01F6/60; D01F6/605; C08J2377/00; C08J2377/10
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
41 words
Optically anisotropic spinning dope of claim 1 consisting essentially of: about 5 to 25 weight percent of said polycarbonamide having an inherent viscosity between about 0.7 and 4.5, about 0.5 to 8 weight percent of (II-A), and the remainder being (III-A).
Claim 2
Dependent Claim
143 words
Optically anisotropic spinning dope consisting essentially of: I. from about 5 to 25 percent by weight of a polycarbonamide having an inherent viscosity of at least 0.7 and consisting essentially of recurring units of the formula: II. from 0.5 to 8 percent by weight of a salt selected from the group consisting of: II-A. lithium chloride and II-B. calcium chloride, and III. a liquid medium consisting essentially of: 25 to 67 weight percent of hexamethylphosphoramide with the balance being at least one amide medium selected from the group consisting of N,N-dimethylacetamide and N-methylpyrrolidone-2, said polycarbonamide being present in the dope in a concentration above the level at which there is a decrease in viscosity with increasing concentration represented by a sharp discontinuity in the slope of the plot of the dope viscosity vs. polymer concentration curve without the formation of a solid phase.
Claim 3
Dependent Claim
59 words
Optically anisotropic spinning dope of claim 3 consisting essentially of: about 5 to 15 weight percent of said polycarbonamide having an inherent viscosity between about 0.7 and 5, about 0.5 to 5 weight percent of (II-A) and, the remainder being a mixture of hexamethylphosphoramide and N-methylpyrrolidone-2, wherein hexamethylphosphoramide comprises 33 to 67 percent by volume of the said mixture.
Claim 4
Dependent Claim
60 words
Optically anisotropic spinning dope of claim 3 consisting essentially of: about 5 to 15 weight percent of said polycarbonamide having an inherent viscosity between about 0.7 and 5, about 0.5 to 5 weight percent of (II-A) and, the remainder being a mixture of hexamethylphosphoramide and N, N-dimethylacetamide, wherein hexamethylphosphoramide comprises 33 to 67 percent by volume of the said mixture.
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) | 1975-06-27 | 1975-12-27 | 1976-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-27 | 1979-12-27 | 1980-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-27 | 1983-12-27 | 1984-06-27 | $7700.00 | Window Closed / Lapsed |