US4075269A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for producing wholly aromatic polyamide fibers of high strength
Assignee: Celanese Corp
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Filing: 1976-09-23
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Granted: 1978-02-21
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Expires: 1996-09-23
Abstract
Abstract An improved process for preparing wholly aromatic polyamide fibers of high performance charcteristics is provided. The process includes the steps of providing a spinning solution of a wholly aromatic polyamide, the polyamide having a sulfur content as sulfonic acid and/or sulfonate groups attached to the aromatic nuclei of at least 0.5 percent by weight based on the weight of the polyamide; spinning the spinning solution of the wholly aromatic polyamide to produce an as-spun fiber having an inherent viscosity of at least 1.0; and heat treating the as-spun fiber under sufficient tension to maintain a constant length or to elongate the fiber up to about 5 percent of the as-spun length while heating within a range of about 150° C. to about 650° C. The resulting fibers have a tenacity of at least 15 grams per denier, an elongation of at least 1.5 percent, and an initial modulus of at least 400 grams per denier.
Inventors
- 👤 Rufus S. Jones, Jr.
- 👤 Marshall Tan
- 👤 Eui Won Choe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 07:46
CPC Classifications
D; D01; D01F; D01F6/00; D01F6/58; D01F6/60; D01F6/605; C; C08; C08G; C08G69/00; C08G69/02; C08G69/26; C08G69/32
Claims Analysis
Total Claims: 35
Claim 1
Independent Claim
179 words
An improved process for preparing wholly aromatic polyamide fibers comprising: a. providing a spinning solution containing from about 10 to 30 percent by weight of a wholly aromatic polyamide having (1) chain extending bonds from the aromatic nuclei thereof which are coaxial or parallel and oppositely directed, and (2) a sulfur content of at least 0.5 percent by weight as sulfonic acid and/or sulfonate groups attached to said aromatic nuclei of said wholly aromatic polyamide; b. solution spinning said spinning solution of said wholly aromatic polyamide through a spinning jet to provide as-spun fibers having an inherent viscosity of at least 1.0; and c. thermally treating said as-spun fibers at a temperature within the range of about 150° to 650° C. while under a longitudinal tension sufficient to maintain a constant length or to elongate the fibers up to about 5 percent of the as-spun length thereby producing fibers having a single filament tenacity of at least 15 grams per denier, an elongation of at least 1.5 percent, and an initial modulus of at least 400 grams per denier.
Claim 2
Dependent Claim
179 words
An improved process for preparing wholly aromatic polyamide fibers comprising: a. providing a spinning solution containing from about 10 to 30 percent by weight of a wholly aromatic polyamide having (1) chain extending bonds from the aromatic nuclei thereof which are coaxial or parallel and oppositely directed, and (2) a sulfur content of at least 0.5 percent by weight as sulfonic acid and/or sulfonate groups attached to said aromatic nuclei of said wholly aromatic polyamide; b. solution spinning said spinning solution of said wholly aromatic polyamide through a spinning jet to provide as-spun fibers having an inherent viscosity of at least 1.0; and c. thermally treating said as-spun fibers at a temperature within the range of about 150° to 650° C. while under a longitudinal tension sufficient to maintain a constant length or to elongate the fibers up to about 5 percent of the as-spun length thereby producing fibers having a single filament tenacity of at least 15 grams per denier, an elongation of at least 1.5 percent, and an initial modulus of at least 400 grams per denier.
Claim 3
Dependent Claim
31 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 1 wherein said wholly aromatic polyamide has a sulfur content of about 0.5 to 10 percent by weight.
Claim 4
Dependent Claim
22 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 1 wherein said wholly aromatic polyamide is sulfonated poly-p-phenyleneterephthalamide.
Claim 5
Dependent Claim
50 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 1 wherein said sulfur content initially is imparted to said wholly aromatic polyamide while dissolved in concentrated sulfuric acid at a temperature of about 75° to 95° C. for a period of about 14 to 50 hours.
Claim 6
Dependent Claim
48 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 1 wherein said sulfur content initially is imparted to said wholly aromatic polyamide while dissolved in fuming sulfuric acid at a temperature not exceeding about 25° C. for a period not exceeding about 1 hour.
Claim 7
Dependent Claim
32 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 1 wherein said spinning solution contains about 18 to 23 percent by weight of said sulfur-containing wholly aromatic polyamide.
Claim 8
Dependent Claim
24 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 1 wherein said spinning solution is solution spun employing dry-jet wet-spinning.
Claim 9
Dependent Claim
40 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 1 wherein during said solution spinning of step (b) said fibers are wound-up at speeds of about 2 to 6 times greater than the theoretical jet speed.
Claim 10
Dependent Claim
27 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 1 wherein said as-spun fibers have an inherent viscosity of about 1.0 to 7.0.
Claim 11
Dependent Claim
30 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 1 wherein said as-spun fibers are washed and dried prior to said thermal treatment of step (c).
Claim 12
Dependent Claim
30 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 1 wherein said as-spun fibers are thermally treated at a temperature of about 350° to 550° C.
Claim 13
Dependent Claim
26 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 1 wherein said as-spun fibers are thermally treated in an inert gaseous atmosphere.
Claim 14
Dependent Claim
197 words
An improved process for preparing wholly aromatic polyamide fibers comprising: a. providing a spinning solution containing from about 10 to 30 percent by weight of a wholly aromatic polyamide having (1) chain extending bonds from the aromatic nuclei thereof which are coaxial or parallel and oppositely directed, and (2) a sulfur content of about 0.5 to 10 percent by weight as sulfonic acid and/or sulfonate groups attached to said aromatic nuclei of said wholly aromatic polyamide; b. solution spinning said spinning solution of said wholly aromatic polyamide through a spinning jet to provide as-spun fibers having an inherent viscosity of about 1.0 to 7.0 while employing a wind-up speed about 2 to 6 times greater than the theoretical jet speed; and c. thermally treating said as-spun fibers at a temperature within the range of about 150° to 650° C. while under a longitudinal tension sufficient to maintain a constant length or to elongate the fibers up to about 5 percent of the as-spun length thereby producing fibers having a single filament tenacity of at least 15 grams per denier, an elongation of at least 1.5 percent, and an initial modulus of at least 400 grams per denier.
Claim 15
Dependent Claim
197 words
An improved process for preparing wholly aromatic polyamide fibers comprising: a. providing a spinning solution containing from about 10 to 30 percent by weight of a wholly aromatic polyamide having (1) chain extending bonds from the aromatic nuclei thereof which are coaxial or parallel and oppositely directed, and (2) a sulfur content of about 0.5 to 10 percent by weight as sulfonic acid and/or sulfonate groups attached to said aromatic nuclei of said wholly aromatic polyamide; b. solution spinning said spinning solution of said wholly aromatic polyamide through a spinning jet to provide as-spun fibers having an inherent viscosity of about 1.0 to 7.0 while employing a wind-up speed about 2 to 6 times greater than the theoretical jet speed; and c. thermally treating said as-spun fibers at a temperature within the range of about 150° to 650° C. while under a longitudinal tension sufficient to maintain a constant length or to elongate the fibers up to about 5 percent of the as-spun length thereby producing fibers having a single filament tenacity of at least 15 grams per denier, an elongation of at least 1.5 percent, and an initial modulus of at least 400 grams per denier.
Claim 16
Dependent Claim
31 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 13 wherein said wholly aromatic polyamide has a sulfur content of about 0.5 to 3 percent by weight.
Claim 17
Dependent Claim
22 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 13 wherein said wholly aromatic polyamide is sulfonated poly-p-phenyleneterephthalamide.
Claim 18
Dependent Claim
50 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 13 wherein said sulfur content initially is imparted to said wholly aromatic polyamide while dissolved in concentrated sulfuric acid at a temperature of about 75° to 95° C. for a period of about 14 to 50 hours.
Claim 19
Dependent Claim
48 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 13 wherein said sulfur content initially is imparted to said wholly aromatic polyamide while dissolved in fuming sulfuric acid at a temperature not exceeding about 25° C. for a period not exceeding about 1 hour.
Claim 20
Dependent Claim
32 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 13 wherein said spinning solution contains about 18 to 23 percent by weight of said sulfur-containing wholly aromatic polyamide.
Claim 21
Dependent Claim
24 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 13 wherein said spinning solution is solution spun employing dry-jet wet-spinning.
Claim 22
Dependent Claim
41 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 13 wherein during said solution spinning of step (b) said fibers are wound-up at a speed of about 3 to 5 times greater than the theoretical jet speed.
Claim 23
Dependent Claim
27 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 13 wherein said as-spun fibers have an inherent viscosity of about 1.0 to 3.0.
Claim 24
Dependent Claim
30 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 13 wherein said as-spun fibers are washed and dried prior to said thermal treatment of step (c).
Claim 25
Dependent Claim
30 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 13 wherein said as-spun fibers are thermally treated at a temperature of about 350° to 550° C.
Claim 26
Dependent Claim
26 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 13 wherein said as-spun fibers are thermally treated in an inert gaseous atmosphere.
Claim 27
Dependent Claim
185 words
An improved process for preparing wholly aromatic polyamide fibers comprising: a. providing a spinning solution containing about 18 to 23 percent by weight of sulfonated poly-p-phenyleneterephthalamide having a sulfur content of about 0.8 to 1.7 percent by weight as sulfonic acid and/or sulfonate groups attached to the aromatic nuclei of said poly-p-phenyleneterephthalamide; b. solution spinning said spinning solution of sulfonated poly-p-phenyleneterephthalamide through a spinning jet to provide as-spun fibers having an inherent viscosity of about 1.0 to 3.0 while employing a wind-up speed about 3 to 5 times greater than the theoretical jet speed; c. washing and drying said as-spun fibers; and d. thermally treating said as-spun fibers while present in an inert gaseous atmosphere at a temperature within the range of about 350° to 550° C. while under a longitudinal tension sufficient to maintain a constant length or to elongate the fibers up to about 5 percent of the as-spun length thereby producing fibers having a single filament tenacity of at least 15 grams per denier, an elongation of at least 1.5 percent, and an initial modulus of at least 400 grams per denier.
Claim 28
Dependent Claim
185 words
An improved process for preparing wholly aromatic polyamide fibers comprising: a. providing a spinning solution containing about 18 to 23 percent by weight of sulfonated poly-p-phenyleneterephthalamide having a sulfur content of about 0.8 to 1.7 percent by weight as sulfonic acid and/or sulfonate groups attached to the aromatic nuclei of said poly-p-phenyleneterephthalamide; b. solution spinning said spinning solution of sulfonated poly-p-phenyleneterephthalamide through a spinning jet to provide as-spun fibers having an inherent viscosity of about 1.0 to 3.0 while employing a wind-up speed about 3 to 5 times greater than the theoretical jet speed; c. washing and drying said as-spun fibers; and d. thermally treating said as-spun fibers while present in an inert gaseous atmosphere at a temperature within the range of about 350° to 550° C. while under a longitudinal tension sufficient to maintain a constant length or to elongate the fibers up to about 5 percent of the as-spun length thereby producing fibers having a single filament tenacity of at least 15 grams per denier, an elongation of at least 1.5 percent, and an initial modulus of at least 400 grams per denier.
Claim 29
Dependent Claim
47 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 25 wherein said sulfonated poly-p-phenyleneterephthalamide is initially formed while poly-p-phenyleneterephthalamide is dissolved in concentrated sulfuric acid at a temperature of about 75° to 95° C. for a period of about 14 to 50 hours.
Claim 30
Dependent Claim
45 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 25 wherein said sulfonated poly-p-phenyleneterephthalamide is initially formed while poly-p-phenyleneterephthalamide is dissolved in fuming sulfuric acid at a temperature not exceeding about 25° C. for a period not exceeding about 1 hour.
Claim 31
Dependent Claim
26 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 25 wherein said spinning solution employs concentrated sulfuric acid as the spinning solvent.
Claim 32
Dependent Claim
24 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 25 wherein said spinning solution is solution spun employing dry-jet wet-spinning.
Claim 33
Dependent Claim
37 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 25 wherein said as-spun fibers are thermally treated while present in said inert gaseous atmosphere at a temperature of about 450° to 500° C.
Claim 34
Dependent Claim
29 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 25 wherein said inert gaseous atmosphere in which said thermal treatment is carried out is nitrogen.
Claim 35
Dependent Claim
39 words
An improved process for preparing wholly aromatic polyamide fibers in accordance with claim 25 wherein said thermal treatment is carried out at a temperature in the range of about 350° to 550° C. for about 3 to 9 seconds.
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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) | 1981-02-20 | 1981-08-22 | 1982-02-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-20 | 1985-08-22 | 1986-02-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-20 | 1989-08-22 | 1990-02-21 | $7700.00 | Window Closed / Lapsed |