US4377546A
Expired / Lapsed
US
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Process for producing aromatic heterocyclic polymer alloys
Assignee: United States, UNITED STATES AIR FORCE, Secretary of
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Filing: 1981-08-11
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Granted: 1983-03-22
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Expires: 2001-08-11
Abstract
Abstract A novel method is taught for preparing polymeric alloys composed of a mixture of an aromatic heterocyclic rod-like reinforcing polymer and an aromatic heterocyclic coil-like amorphous mixture with vastly improved mechanical properties.
Inventors
- 👤 Thaddeus E. Helminiak
- 👤 Charles L. Benner
- 👤 Fred E. Arnold
- 👤 George Husman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:56
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/18; C08L; C08L79/00; C08L79/04; D; D01; D01F; D01F6/00; D01F6/88; D01F6/94; C08J2379/00; C08J2379/04
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
245 words
A method for preparing a molecular composite film comprising the steps of: A. forming a solvent mixture composed of (1) about 70 to 99 weight percent of methanesulfonic acid and (2) about one to 30 weight percent of a polymer mixture composed of (a) about 5 to 50 percent of a rod-like, aromatic, heterocyclic polymer and (b) about 50 to 95 weight percent of an amorphous, coil-like, aromatic, heterocyclic polymer; said rod-like, heterocyclic polymer consisting essentially of repeating units having the following structural formula: ##STR12## Wherein X is NH, Nφ, O or S, where φ is phenyl, and Ar is ##STR13## and n is an interger having a value such that the polymer has an intrinsic viscosity of about 5 to 30 dl/g as determined in methanesulfonic acid at 30° C.; and said coil-like, heterocyclic polymer consisting essentially of repeating units having the following structural formula: ##STR14## Wherein x is NH, Nφ, O or S, where φ is phenyl and Ar' is ##STR15## and m is an integer having a value such that the polymer has an intrinsic viscosity of about 2 to 20 dl/g as determined in methanesulfonic acid at 30° C.; B. introducing said solvent mixture into a casting mold positioned within an enclosed chamber containing water vapor; C. permitting said solvent mixture to absorb said water vapor for a period of time sufficient to form a precipitated film; D. recovering said precipitated film from said mold; and E. drying the recovered film.
Claim 2
Independent Claim
245 words
A method for preparing a molecular composite film comprising the steps of: A. forming a solvent mixture composed of (1) about 70 to 99 weight percent of methanesulfonic acid and (2) about one to 30 weight percent of a polymer mixture composed of (a) about 5 to 50 percent of a rod-like, aromatic, heterocyclic polymer and (b) about 50 to 95 weight percent of an amorphous, coil-like, aromatic, heterocyclic polymer; said rod-like, heterocyclic polymer consisting essentially of repeating units having the following structural formula: ##STR12## Wherein X is NH, Nφ, O or S, where φ is phenyl, and Ar is ##STR13## and n is an interger having a value such that the polymer has an intrinsic viscosity of about 5 to 30 dl/g as determined in methanesulfonic acid at 30° C.; and said coil-like, heterocyclic polymer consisting essentially of repeating units having the following structural formula: ##STR14## Wherein x is NH, Nφ, O or S, where φ is phenyl and Ar' is ##STR15## and m is an integer having a value such that the polymer has an intrinsic viscosity of about 2 to 20 dl/g as determined in methanesulfonic acid at 30° C.; B. introducing said solvent mixture into a casting mold positioned within an enclosed chamber containing water vapor; C. permitting said solvent mixture to absorb said water vapor for a period of time sufficient to form a precipitated film; D. recovering said precipitated film from said mold; and E. drying the recovered film.
Claim 3
Dependent Claim
22 words
A method in accordance with claim 1 wherein said rod-like polymer consists essentially of repeating units having the following structural formula: ##STR16##
Claim 4
Dependent Claim
22 words
A method in accordance with claim 1 wherein said coil-like polymer consists essentially of repeating units having the following structural formula: ##STR17##
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-03-21 | 1986-09-20 | 1987-03-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-03-21 | 1990-09-20 | 1991-03-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-03-21 | 1994-09-20 | 1995-03-22 | $7700.00 | Window Closed / Lapsed |