CA2044407A1 - Anisotropic spin dopes of reduced viscosity - Google Patents
Anisotropic spin dopes of reduced viscosityInfo
- Publication number
- CA2044407A1 CA2044407A1 CA 2044407 CA2044407A CA2044407A1 CA 2044407 A1 CA2044407 A1 CA 2044407A1 CA 2044407 CA2044407 CA 2044407 CA 2044407 A CA2044407 A CA 2044407A CA 2044407 A1 CA2044407 A1 CA 2044407A1
- Authority
- CA
- Canada
- Prior art keywords
- poly
- polymer
- viscosity
- solution
- reciprocal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 229920000642 polymer Polymers 0.000 claims abstract description 18
- 229920000137 polyphosphoric acid Polymers 0.000 claims abstract description 8
- HSAOVLDFJCYOPX-UHFFFAOYSA-N 2-[4-(1,3-benzothiazol-2-yl)phenyl]-1,3-benzothiazole Chemical compound C1=CC=C2SC(C3=CC=C(C=C3)C=3SC4=CC=CC=C4N=3)=NC2=C1 HSAOVLDFJCYOPX-UHFFFAOYSA-N 0.000 claims abstract description 6
- XTHPWXDJESJLNJ-UHFFFAOYSA-N sulfurochloridic acid Chemical class OS(Cl)(=O)=O XTHPWXDJESJLNJ-UHFFFAOYSA-N 0.000 claims abstract description 6
- COVZYZSDYWQREU-UHFFFAOYSA-N Busulfan Chemical compound CS(=O)(=O)OCCCCOS(C)(=O)=O COVZYZSDYWQREU-UHFFFAOYSA-N 0.000 claims abstract description 3
- AFVFQIVMOAPDHO-UHFFFAOYSA-N Methanesulfonic acid Chemical compound CS(O)(=O)=O AFVFQIVMOAPDHO-UHFFFAOYSA-N 0.000 claims description 21
- 238000000034 method Methods 0.000 claims description 9
- 238000006116 polymerization reaction Methods 0.000 claims description 7
- 238000009987 spinning Methods 0.000 claims description 6
- 229940098779 methanesulfonic acid Drugs 0.000 claims description 5
- 239000002904 solvent Substances 0.000 claims description 5
- ICXAPFWGVRTEKV-UHFFFAOYSA-N 2-[4-(1,3-benzoxazol-2-yl)phenyl]-1,3-benzoxazole Chemical compound C1=CC=C2OC(C3=CC=C(C=C3)C=3OC4=CC=CC=C4N=3)=NC2=C1 ICXAPFWGVRTEKV-UHFFFAOYSA-N 0.000 claims description 4
- 230000001112 coagulating effect Effects 0.000 claims description 4
- 239000000835 fiber Substances 0.000 claims description 4
- 239000012046 mixed solvent Substances 0.000 claims 1
- KEQGZUUPPQEDPF-UHFFFAOYSA-N 1,3-dichloro-5,5-dimethylimidazolidine-2,4-dione Chemical compound CC1(C)N(Cl)C(=O)N(Cl)C1=O KEQGZUUPPQEDPF-UHFFFAOYSA-N 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 230000003466 anti-cipated effect Effects 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 239000013505 freshwater Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 229920002521 macromolecule Polymers 0.000 description 1
- AYOOGWWGECJQPI-NSHDSACASA-N n-[(1s)-1-(5-fluoropyrimidin-2-yl)ethyl]-3-(3-propan-2-yloxy-1h-pyrazol-5-yl)imidazo[4,5-b]pyridin-5-amine Chemical compound N1C(OC(C)C)=CC(N2C3=NC(N[C@@H](C)C=4N=CC(F)=CN=4)=CC=C3N=C2)=N1 AYOOGWWGECJQPI-NSHDSACASA-N 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000010791 quenching Methods 0.000 description 1
Classifications
-
- D—TEXTILES; PAPER
- D01—NATURAL OR MAN-MADE THREADS OR FIBRES; SPINNING
- D01F—CHEMICAL FEATURES IN THE MANUFACTURE OF ARTIFICIAL FILAMENTS, THREADS, FIBRES, BRISTLES OR RIBBONS; APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OF CARBON FILAMENTS
- D01F6/00—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof
- D01F6/58—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from homopolycondensation products
- D01F6/74—Monocomponent artificial filaments or the like of synthetic polymers; Manufacture thereof from homopolycondensation products from polycondensates of cyclic compounds, e.g. polyimides, polybenzimidazoles
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Textile Engineering (AREA)
- Artificial Filaments (AREA)
- Macromolecular Compounds Obtained By Forming Nitrogen-Containing Linkages In General (AREA)
Abstract
Title Anisotropic Spin Dopes of Reduced Viscosity Abstract of the Disclosure Poly-p-phenylenebenzobisthiazole and similar polymers as prepared in polyphosphoric acid can be used as spin dopes upon addition of methanesulfonic or chlorosulfonic acids.
Description
2~44~07 ~itle Anisotropic Spln Dopes of Reduced vi~c06ity Thls application is a C-I-P of my application Serial No. 07/315,654 filed February 27, 19~9 and my now abandoned application~ Serial Nos. 07/091,001 filed September 2, 1987; 07/033,259 filed Apr~l 2, 1987 and 07/919,028 filed October 15, 19~6.
~ackground of the Invention Poly-p-phenylenebenzobisthiazole, poly-p-phenylenebenzobisoxazole and poly-2,5-benzoxazole are commonly prepared ln polyphosphoric acid ~PPA). (See U.S. Patent Nos. 4,225,700 and 4,533,693). Liquid crystalline solution6 of poly-p-phenylenebisthiazole in solvent~ such as polyphosphoric acid, methanesulfonic acid and chlorosulfonic acid are taught in U.S. 4,225,700 to be u~eful in the preparatlon of high modulus, high strength material~ having excellent thermal stability. There are 6ubstantial problems involved, however, in ~pinning the highl~ vi6cous ~olution that i~ available directly ~rom the polymerization. See Macromolecules 1981, V. 14, pp.
1135-1139 which de6cribe6 attempts to spln polybenzobisthiazole dlrectly from the polymerizatlon medium ~polyphosphorlc acld) containlng 5-6% polymer.
Attempts to spln the hlghly v16cou6 601ution taxe6 the material strength llmlts of the equipment and causes excessive wear. A solutlon to this problem i6 a worthwhile ob~ective.
Figure The Figure is a curve of dope vlscoslty a~ a function of concentration at 170C at a shear rate of 0.1 reclprocal second for a solution of poly-p-phenylenebenzobisthlazole in polyphosphoric acid.
20~4407 Summary of the Inventlon This invention provides an improved process for spinning a polymer selected from poly-p-phenylenebenzobisthia~ole, poly-p-phenylenebenzobisoxazole or poly-2,5-benzoxazole directly from the polyphosphoric acid 601ution in which it was prepared, comprising adding to the polymer solution an amount of a solvent selected from methanesulfonic or chlorosulfonic acids sufficient to reduce the viscosity to less than about 50,000 poises at 170C and 0.1 reciprocal second shear rate, spinning the solution through a 6pinneret and coagulating the extrudate to form fiber.
_etailed Description of the Invention In accordance with the present invention, the viCcosity of solutions of poly-p-phenylenebenzobisthiazole, poly-p-phenylenebenzobisoxazole or poly-2,5-benzoxazole in their polyphosphoric acid ~PPA) polymerization medium is reduced by addition of methanesulfonic acid ~MSA) or chlorosulfonic acid to yield spin dopes that can be readily extruded to form fiber. This simple technique substantially eliminates the difficulties mentioned in the art ~nd experienced prevlously by the present applicant.
As-produced solutions of the aforementioned polymers ln the PPA polymerization medium are highly vlscous materials and in general can be spun only with great dlfflculty if at all. To help wlth thls problem, splnning speeds can be reduced, stronger equipment can be used to withstand the greater pressures which are needed to transfer the solution and clearances can be increased among other stop-gap mea6ures. The problem is avoided if the polymer is separated from the polymerization medium and redissolved in methanesulfonic acid, for example and then 6pun (See Japanese Patent Application Disclosure Tokukai 61-28015, 1986). Attempts to reduce viscosity by formlng more dllute solutions by addition of PPA to the as-produced polymer solution in PPA does not accomplish the desired ob~ective and, in fact, may increase the vi6c06ity as seen ln the Figure. The addltlon of MSA brlngs the vl~c061ty down to readlly spinnable levels.
The polymers under consideration and their preparation are well-known ln the art. The polymer intrin6ic visco6itie6 ~I.V. )range from about 10 to 25 with poly-p-2,5-benzoxazole generally exhibiting visc06ity levels at the upper end of this range. The palymer concentration6 in PPA a6 produced, can vary from 5 to 15 wt.% but i6 generally at least 10%.
It is anticipated that commercial spinning of the dope6 will be at a temperature below 130C and it is important that the spin dope viscosity be sufficiently low 60 that lt can be handled, i.e. transferred and extruded, with commercially available equipment. The viscosity of the a6-produced 601ution of the polymer in the polymerization medium at any particular temperature and 6hear rate will depend on the polymer, its molecular weight and it6 concentration in the polymerization medlum. For thl~ reason, the amount of MSA to be added wlll nece66arlly vary. AB an acceptable 6tandard, a spin-dope visco61ty of les6 than 50,000 poises and preferably le66 than 30,000 poise6 at 170C and 0.1 reciprocal second 6hear rate is u8ed. Slnce the vi6c06ity of the a6-produced 601ution6 of polymer ln the polymerlzation medium often exceed 100,000 polBes at 170C and 0.1 reciprocal second shear rate, the MSA or chloro6ulfonic acid i6 added to reduce the visco6ity to a readlly ~plnnable level. It is expected that the final mlxed solvent of the 6pin dope will contain from 20 to 60 wt. % MSA. Amounts of MSA in exce66 of ~0 wt. % are not preferred becau6e the polymer content will be too low for economic operation. One 6hould al~o avoid the po861blllty of converting from an optically anisotropic to an 160troplc spin-dope.
20~go7 The figure is a plot of v~ sco~ity ver6u~
concentration of a solution of poly-p-phenylenebenzobisthiazole in polyphosphoric acid at 170C
and at a shear rate of 0.1 reciprocal second. As can be seen in the plot, the viscosity of the solution rises as the concentration is increased to about 4% (the isotropic range) and then drops precipitously beyond that point as the concentration increases further. The addition of MSA
or chlorosulfonic acid in essence reduces the viscosity by lowering the curve.
After the spinnable dope containing the mixture of ~olvents has been prepared, it may be spun by procedures well known in the art as shown by Japanese Patent Application Disclosure Tokukai 61-28015 (1986) and U.S.
Patent No. 4,533,693. The spln dope is extruded through a spinneret into a coagulating bath from which the fibers are withdrawn. Preferably the extruded dope is first passed through an air gap prior to entry into the coagulating bath which may be an aqueou6 solution or water it6elf.
The following example6 are illustrative of the lnventlon and are not intended as limiting.
Example 1 To 321.7 grams of a dope containlng 15~ by wt.
poly-p-phenylenebenzobisthiazole (I.V. - 22.1) in PPA and havlng a 100,000-polse vlsco6ity ~measured at 170C and 0.1 reclprocal second shear rate) wag added 117.2 grams of MSA.
The mlxture wa6 mixed in a glass vessel continuously purged with nitrogen, u~lng a double helical mixer for 6 hours at 95C. An additional 65.1 grams of MSA was added with mixing overnight at 102C. The resulting dope had a concentration of 10.6% and viscosity of 61,000 poises mea6ured at 110C. The calculated dope viscosity at 170C
and 0.1 reciprocal second shear rate is 24,000 poises.
Example 2 49 lbs. of the same 15% 100,000-poise dope a6 in Example 1 wa~ mixed wlth 27.8 lbs of MSA in a 10-gallon " 20~9~07 Atlantic Mixer. The mixture was mixed under vacuum at 40 rpm for 3 hours. The resulting dope of 10.6% concentration was extruded at 110C through a 290-hole spinneret through an air-gap and into a water quench bath. The resulting yarns were washed with fresh water until most of the acid solvents were extracted. The a~-spun wet yarns were then heat-treated on the run (30 meters/min.) under 1.0 gpd tension at 670C for 9 seconds. The as-spun yarns had filament strengths ranging from 13.6 to 15.0 gpd and moduli of from 380 to 44g gpd. The heat-treated yarns had filament strengths of about 20 gpd and moduli between about 1,800 and 2,000 gpd.
~xample 3 46 lbs. of a 15% dope as in Example 1 was mixed with 26.0 lbs of MSA in a 10-gallon Atlantic Mixer. The mixing and proce~sing conditions of Example 2 were used.
The as-spun yarns had filament strengths of from 13.1 to 14.8 gpd and moduli of from 286 to 411 gpd. The heat-treated yarns had filament strengths of from 19.3 to 21.9 gpd and moduli between about 1,800 and 2,000 gpd.
~ackground of the Invention Poly-p-phenylenebenzobisthiazole, poly-p-phenylenebenzobisoxazole and poly-2,5-benzoxazole are commonly prepared ln polyphosphoric acid ~PPA). (See U.S. Patent Nos. 4,225,700 and 4,533,693). Liquid crystalline solution6 of poly-p-phenylenebisthiazole in solvent~ such as polyphosphoric acid, methanesulfonic acid and chlorosulfonic acid are taught in U.S. 4,225,700 to be u~eful in the preparatlon of high modulus, high strength material~ having excellent thermal stability. There are 6ubstantial problems involved, however, in ~pinning the highl~ vi6cous ~olution that i~ available directly ~rom the polymerization. See Macromolecules 1981, V. 14, pp.
1135-1139 which de6cribe6 attempts to spln polybenzobisthiazole dlrectly from the polymerizatlon medium ~polyphosphorlc acld) containlng 5-6% polymer.
Attempts to spln the hlghly v16cou6 601ution taxe6 the material strength llmlts of the equipment and causes excessive wear. A solutlon to this problem i6 a worthwhile ob~ective.
Figure The Figure is a curve of dope vlscoslty a~ a function of concentration at 170C at a shear rate of 0.1 reclprocal second for a solution of poly-p-phenylenebenzobisthlazole in polyphosphoric acid.
20~4407 Summary of the Inventlon This invention provides an improved process for spinning a polymer selected from poly-p-phenylenebenzobisthia~ole, poly-p-phenylenebenzobisoxazole or poly-2,5-benzoxazole directly from the polyphosphoric acid 601ution in which it was prepared, comprising adding to the polymer solution an amount of a solvent selected from methanesulfonic or chlorosulfonic acids sufficient to reduce the viscosity to less than about 50,000 poises at 170C and 0.1 reciprocal second shear rate, spinning the solution through a 6pinneret and coagulating the extrudate to form fiber.
_etailed Description of the Invention In accordance with the present invention, the viCcosity of solutions of poly-p-phenylenebenzobisthiazole, poly-p-phenylenebenzobisoxazole or poly-2,5-benzoxazole in their polyphosphoric acid ~PPA) polymerization medium is reduced by addition of methanesulfonic acid ~MSA) or chlorosulfonic acid to yield spin dopes that can be readily extruded to form fiber. This simple technique substantially eliminates the difficulties mentioned in the art ~nd experienced prevlously by the present applicant.
As-produced solutions of the aforementioned polymers ln the PPA polymerization medium are highly vlscous materials and in general can be spun only with great dlfflculty if at all. To help wlth thls problem, splnning speeds can be reduced, stronger equipment can be used to withstand the greater pressures which are needed to transfer the solution and clearances can be increased among other stop-gap mea6ures. The problem is avoided if the polymer is separated from the polymerization medium and redissolved in methanesulfonic acid, for example and then 6pun (See Japanese Patent Application Disclosure Tokukai 61-28015, 1986). Attempts to reduce viscosity by formlng more dllute solutions by addition of PPA to the as-produced polymer solution in PPA does not accomplish the desired ob~ective and, in fact, may increase the vi6c06ity as seen ln the Figure. The addltlon of MSA brlngs the vl~c061ty down to readlly spinnable levels.
The polymers under consideration and their preparation are well-known ln the art. The polymer intrin6ic visco6itie6 ~I.V. )range from about 10 to 25 with poly-p-2,5-benzoxazole generally exhibiting visc06ity levels at the upper end of this range. The palymer concentration6 in PPA a6 produced, can vary from 5 to 15 wt.% but i6 generally at least 10%.
It is anticipated that commercial spinning of the dope6 will be at a temperature below 130C and it is important that the spin dope viscosity be sufficiently low 60 that lt can be handled, i.e. transferred and extruded, with commercially available equipment. The viscosity of the a6-produced 601ution of the polymer in the polymerization medium at any particular temperature and 6hear rate will depend on the polymer, its molecular weight and it6 concentration in the polymerization medlum. For thl~ reason, the amount of MSA to be added wlll nece66arlly vary. AB an acceptable 6tandard, a spin-dope visco61ty of les6 than 50,000 poises and preferably le66 than 30,000 poise6 at 170C and 0.1 reciprocal second 6hear rate is u8ed. Slnce the vi6c06ity of the a6-produced 601ution6 of polymer ln the polymerlzation medium often exceed 100,000 polBes at 170C and 0.1 reciprocal second shear rate, the MSA or chloro6ulfonic acid i6 added to reduce the visco6ity to a readlly ~plnnable level. It is expected that the final mlxed solvent of the 6pin dope will contain from 20 to 60 wt. % MSA. Amounts of MSA in exce66 of ~0 wt. % are not preferred becau6e the polymer content will be too low for economic operation. One 6hould al~o avoid the po861blllty of converting from an optically anisotropic to an 160troplc spin-dope.
20~go7 The figure is a plot of v~ sco~ity ver6u~
concentration of a solution of poly-p-phenylenebenzobisthiazole in polyphosphoric acid at 170C
and at a shear rate of 0.1 reciprocal second. As can be seen in the plot, the viscosity of the solution rises as the concentration is increased to about 4% (the isotropic range) and then drops precipitously beyond that point as the concentration increases further. The addition of MSA
or chlorosulfonic acid in essence reduces the viscosity by lowering the curve.
After the spinnable dope containing the mixture of ~olvents has been prepared, it may be spun by procedures well known in the art as shown by Japanese Patent Application Disclosure Tokukai 61-28015 (1986) and U.S.
Patent No. 4,533,693. The spln dope is extruded through a spinneret into a coagulating bath from which the fibers are withdrawn. Preferably the extruded dope is first passed through an air gap prior to entry into the coagulating bath which may be an aqueou6 solution or water it6elf.
The following example6 are illustrative of the lnventlon and are not intended as limiting.
Example 1 To 321.7 grams of a dope containlng 15~ by wt.
poly-p-phenylenebenzobisthiazole (I.V. - 22.1) in PPA and havlng a 100,000-polse vlsco6ity ~measured at 170C and 0.1 reclprocal second shear rate) wag added 117.2 grams of MSA.
The mlxture wa6 mixed in a glass vessel continuously purged with nitrogen, u~lng a double helical mixer for 6 hours at 95C. An additional 65.1 grams of MSA was added with mixing overnight at 102C. The resulting dope had a concentration of 10.6% and viscosity of 61,000 poises mea6ured at 110C. The calculated dope viscosity at 170C
and 0.1 reciprocal second shear rate is 24,000 poises.
Example 2 49 lbs. of the same 15% 100,000-poise dope a6 in Example 1 wa~ mixed wlth 27.8 lbs of MSA in a 10-gallon " 20~9~07 Atlantic Mixer. The mixture was mixed under vacuum at 40 rpm for 3 hours. The resulting dope of 10.6% concentration was extruded at 110C through a 290-hole spinneret through an air-gap and into a water quench bath. The resulting yarns were washed with fresh water until most of the acid solvents were extracted. The a~-spun wet yarns were then heat-treated on the run (30 meters/min.) under 1.0 gpd tension at 670C for 9 seconds. The as-spun yarns had filament strengths ranging from 13.6 to 15.0 gpd and moduli of from 380 to 44g gpd. The heat-treated yarns had filament strengths of about 20 gpd and moduli between about 1,800 and 2,000 gpd.
~xample 3 46 lbs. of a 15% dope as in Example 1 was mixed with 26.0 lbs of MSA in a 10-gallon Atlantic Mixer. The mixing and proce~sing conditions of Example 2 were used.
The as-spun yarns had filament strengths of from 13.1 to 14.8 gpd and moduli of from 286 to 411 gpd. The heat-treated yarns had filament strengths of from 19.3 to 21.9 gpd and moduli between about 1,800 and 2,000 gpd.
Claims (6)
1. An improved process for spinning a polymer selected from poly-p-phenylenebenzobisthiazole, poly-p-phenylenebenzobisoxazole or poly-2,5-benzoxazole directly from the polyphosphoric acid solution in which it was prepared, comprising adding to the polymer solution an amount of a solvent selected from methanesulfonic or chlorosulfonic acids sufficient to reduce the viscosity to less than about 50,000 poises at 170°C and 0.1 reciprocal second shear rate, spinning the solution through a spinneret and coagulating the extrudate to form fiber.
2. The process of claim 1 wherein the polymer solution in the polymerization medium has a viscosity of at least 100,000 poises at 170°C and 0.1 reciprocal second shear rate.
3. The process of claim 2 wherein sufficient methanesulfonic acid is added to reduce the viscosity to less than about 30,000 poises at 170°C and 0.1 reciprocal second shear rate.
4. The process of claim 3 wherein the methanesulfonic acid ranges from 20 to 60 wt.% of the final mixed solvent.
5. The process of claim 1 wherein the spinning solution contains at least 10% of the polymer.
6. The process of claim 1 wherein the polymer has an intrinsic viscosity of from 10 to 25.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US53843790A | 1990-06-15 | 1990-06-15 | |
| US07/538,437 | 1990-06-15 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2044407A1 true CA2044407A1 (en) | 1991-12-16 |
Family
ID=24146934
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2044407 Abandoned CA2044407A1 (en) | 1990-06-15 | 1991-06-12 | Anisotropic spin dopes of reduced viscosity |
Country Status (3)
| Country | Link |
|---|---|
| EP (1) | EP0472834A3 (en) |
| JP (1) | JPH04241111A (en) |
| CA (1) | CA2044407A1 (en) |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5367042A (en) * | 1992-08-27 | 1994-11-22 | The Dow Chemical Company | Process for fabricating oriented polybenzazole films |
| US5429787A (en) * | 1992-12-03 | 1995-07-04 | The Dow Chemical Company | Method for rapid drying of a polybenzazole fiber |
| TW257798B (en) * | 1992-12-03 | 1995-09-21 | Dow Chemical Co | |
| US5286833A (en) * | 1992-12-03 | 1994-02-15 | The Dow Chemical Company | Polybenzazole fiber with ultra-high physical properties |
| US5294390A (en) * | 1992-12-03 | 1994-03-15 | The Dow Chemical Company | Method for rapid spinning of a polybenzazole fiber |
| WO1994012704A1 (en) * | 1992-12-03 | 1994-06-09 | The Dow Chemical Company | Method for rapid drying of a polybenzazole fiber |
| US5288445A (en) * | 1992-12-03 | 1994-02-22 | The Dow Chemical Company | Rapid heat-treatment method for polybenzaole fiber |
| US5296185A (en) * | 1992-12-03 | 1994-03-22 | The Dow Chemical Company | Method for spinning a polybenzazole fiber |
| JPH10110329A (en) * | 1996-10-01 | 1998-04-28 | Toyobo Co Ltd | Polybenzazole fiber and production thereof |
| CN103221337B (en) * | 2010-06-01 | 2016-06-08 | 伊诺弗斯公司 | Polyphosphoric acid composition with reduced viscosity |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4225700A (en) * | 1979-04-23 | 1980-09-30 | Sri International | Thermally stable rod-like polybenzobisthiazole polymers |
| US4606875A (en) * | 1983-04-11 | 1986-08-19 | Celanese Corporation | Process for preparing shaped articles of rigid rod heterocyclic liquid crystalline polymers |
| US4772678A (en) * | 1983-09-15 | 1988-09-20 | Commtech International Management Corporation | Liquid crystalline polymer compositions, process, and products |
| CA1285674C (en) * | 1986-10-15 | 1991-07-02 | E. I. Du Pont De Nemours And Company | Spinnable dopes and articles therefrom |
-
1991
- 1991-06-12 CA CA 2044407 patent/CA2044407A1/en not_active Abandoned
- 1991-06-13 JP JP16741691A patent/JPH04241111A/en active Pending
- 1991-06-14 EP EP19910109761 patent/EP0472834A3/en not_active Withdrawn
Also Published As
| Publication number | Publication date |
|---|---|
| EP0472834A2 (en) | 1992-03-04 |
| JPH04241111A (en) | 1992-08-28 |
| EP0472834A3 (en) | 1992-10-14 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US5194210A (en) | Process for making polyketone fibers | |
| Wojtkowski | Aromatic-aliphatic azomethine ether polymers and fibers | |
| US4457828A (en) | Mesophase pitch having ellipspidal molecules and method for making the pitch | |
| US4162346A (en) | High performance wholly aromatic polyamide fibers | |
| CA2044407A1 (en) | Anisotropic spin dopes of reduced viscosity | |
| US6641765B2 (en) | Polyester multifilament yarn | |
| EP0260922A2 (en) | Aramid copolymer yarn | |
| US5340511A (en) | Production of carbon fibre | |
| US5252394A (en) | Molecular orientation articles molded from high-molecular weight polyethylene and processes for preparing same | |
| EP0255109B1 (en) | Process for producing an acrylic fiber having high fiber characteristics | |
| US20090253890A1 (en) | Aromatic polyamide filament and method of manufacturing the same | |
| EP0647731B1 (en) | Aramid fibres with high tenacity and high titer, process for their manufacture and use thereof | |
| EP0710263B1 (en) | Aliphatic polyamide fibers | |
| US20100154376A1 (en) | Inherently coloured polyester polymers, fibers or filaments and process for producing them | |
| US4810735A (en) | Spinnable dopes and articles therefrom | |
| Weyland | The effect of anisotropy in wet spinning poly (p-phenyleneterephthalamide) | |
| JPS6128015A (en) | Production of poly(p-phenylenebenzo-bis-thiazole fiber | |
| US5137986A (en) | Spinnable dopes and articles therefrom | |
| Gilbert et al. | Preparation of high‐strength/high‐modulus regenerated cellulose fibers from lyotropic mesophases | |
| US5952434A (en) | Spinning dope and fibres spun therefrom | |
| EP0264271B1 (en) | Spinnable dopes and articles therefrom | |
| US5141693A (en) | Process for improving the strength of fibers from anisotropic-melt-forming polyesters | |
| RU2136792C1 (en) | Method of preparing anisotropic polymer solution to form films and fibers | |
| KR930011335B1 (en) | Manufacturing method of high strength, low shrink polyamide | |
| KR940011538B1 (en) | High strength nylon 6 fiber |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Dead |