US4370290A
Expired / Lapsed
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Process for producing aromatic polyimide filaments
Assignee: Ube Corp
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Filing: 1981-05-08
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Granted: 1983-01-25
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Expires: 2001-05-08
Abstract
Abstract Aromatic polyimide fibers having an enhanced mechanical strength are produced by a process comprising the steps of: preparing a spinning dope solution of at least one aromatic polyimide having 90 molar % or more of a recurring unit of the formula (I): <IMAGE> wherein R is a divalent aromatic radical, in a phenolic solvent; converting the dope solution into at least one filamentary stream thereof; solidifying the filamentary dope solution stream by removing the solvent therefrom to provide at least one undrawn filament, and; drawing the undrawn filament at a temperature of 20 DEG to 600 DEG C. at a draw ratio of 1.5 to 5.0.
Inventors
- 👤 Hiroshi Makino
- 👤 Yoshihiro Kusuki
- 👤 Takashi Harada
- 👤 Hiroshi Shimazaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 14:54
CPC Classifications
D; D01; D01F; D01F6/00; D01F6/58; D01F6/74; C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1067; C08L; C08L79/00; C08L79/04; C08L79/08
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
127 words
A process for producing aromatic polyimide filaments, comprising the steps of: (1) preparing a spinning dope solution of a polymer material consisting of at least one aromatic polyimide having at least 90 molar % of a recurring unit of the formula (I): ##STR7## wherein R represents a divalent aromatic radical, in a solvent comprising, as a main component thereof, at least one phenolic compound; (2) extruding said spinning dope solution through at least one spinning hole to form at least one filamentary stream thereof, (3) solidifying said filamentary stream of said spinning dope solution to provide at least one undrawn aromatic polyimide filament, and; (4) drawing said undrawn filament at a temperature of from 20° to 600° C. at a draw ratio of from 1.5 to 5.0.
Claim 2
Dependent Claim
127 words
A process for producing aromatic polyimide filaments, comprising the steps of: (1) preparing a spinning dope solution of a polymer material consisting of at least one aromatic polyimide having at least 90 molar % of a recurring unit of the formula (I): ##STR7## wherein R represents a divalent aromatic radical, in a solvent comprising, as a main component thereof, at least one phenolic compound; (2) extruding said spinning dope solution through at least one spinning hole to form at least one filamentary stream thereof, (3) solidifying said filamentary stream of said spinning dope solution to provide at least one undrawn aromatic polyimide filament, and; (4) drawing said undrawn filament at a temperature of from 20° to 600° C. at a draw ratio of from 1.5 to 5.0.
Claim 3
Dependent Claim
33 words
The process as claimed in claim 1, wherein the divalent aromatic group represented by R in the formula (I) is a residue of an aromatic diamine from which two amino groups are excluded.
Claim 4
Dependent Claim
54 words
The process as claimed in claim 1, wherein said aromatic polyimide has a logarithmic viscosity of from 0.3 to 7.0, determined at a concentration of 0.5 g per 100 ml of a mixture solvent of 4 parts by volume of P-chlorophenol and 1 part by volume of O-chlorophenol at a temperature of 30° C.
Claim 5
Dependent Claim
62 words
The process as claimed in claim 1, wherein said aromatic polyimide is a polymerization-and-imidization product of a tetracarboxylic acid component comprising at least 90 molar % of at least one biphenyl tetracarboxylic acid or its anhydride, salt or ester with a diamine component comprising at least one aromatic diamine of the formula (II): H.sub.2 N--R--NH.sub.2 (II) wherein R is as defined above.
Claim 6
Dependent Claim
26 words
The process as claimed in claim 4, wherein said tetracarboxylic acid component is selected from the group consisting of 3,3',4,4'-biphenyl tetracarboxylic anhydride and 2,3,3',4'-biphenyl tetracarboxylic anhydride.
Claim 7
Dependent Claim
58 words
The process as claimed in claim 4, wherein said tetracarboxilic acid component contains 10 molar % or less of at least one member selected from the group consisting of pyromellitic acid, 3,3',4,4'-benzophenone tetracarboxylic acid, 2,2-bis (3,4-dicarboxyphenyl) propane, bis (3,4-dicarboxyphenyl) sulfone, bis (3,4-dicarboxyphenyl) ether, bis (3,4-dicarboxyphenyl) thioether, butane tetracarboxylic acid, and anhydrides, salts and esters of the above-mentioned compounds.
Claim 8
Dependent Claim
105 words
The process as claimed in claim 4, wherein said aromatic diamine is selected from the group consisting of those of the formulae (III) and (IV): ##STR8## wherein R 1 and R 2 respectively represent, independently from each other, a member selected from the group consisting of hydrogen atom, lower alkyl radicals having 1 to 3 carbon atoms and lower alkoxyl radicals having 1 to 3 carbon atoms; A represents a divalent linking member selected from the class consisting of --O--, --S--, --C--, --SO 2 --, --SO--, --CH 2 -- and --C(CH 3 ) 2 --, and m represents an integer of from 1 to 4.
Claim 9
Dependent Claim
33 words
The process as claimed in claim 1, wherein said phenolic compound has a melting point of 100° C. or less and a boiling point of about 300° C. or less under atmospheric pressure.
Claim 10
Dependent Claim
28 words
The process as claimed in claim 1, wherein said phenolic compound is selected from the group consisting of phenol, alkyl-substituted monohydric phenol compounds and halogenated monohydric phenol compounds.
Claim 11
Dependent Claim
28 words
The process as claimed in claim 9, wherein said alkyl-substituted monohydric phenol compound is selected from the group consisting of O-, m- and P-cresols, 3,5-xylenol, carvacrol and thymol.
Claim 12
Dependent Claim
54 words
The process as claimed in claim 9, wherein said monohydric halogenated phenol compound is selected from the group consisting of those of the formula (VII): ##STR9## wherein R 3 represents a member selected from the group consisting of hydrogen atom and alkyl radicals having 1 to 3 carbon atoms and X represents halogen atoms.
Claim 13
Dependent Claim
22 words
The process as claimed in claim 1, wherein said spinning dope solution contains 5 to 30% by weight of said polymer material.
Claim 14
Dependent Claim
30 words
The process as claimed in claim 1, wherein said spinning dope solution has a rotation viscosity of at least 500 centiposes at a temperature of from 0° to 150° C.
Claim 15
Dependent Claim
50 words
The process as claimed in claim 1, wherein said solidification is carried out by introducing said filamentary stream of said spinning dope solution into a coagulating liquid which is compatible with said solvent but not compatible with said polymer material, to coagulate said filamentary stream of said spinning dope solution.
Claim 16
Dependent Claim
49 words
The process as claimed in claim 14, wherein said coagulating liquid comprises at least one member selected from the groups consisting of water, lower aliphatic alcohols having 1 to 5 carbon atoms, lower aliphatic ketones having 3 to 5 carbon atoms, tetrahydrofuran, dioxane, ethyleneglycol monomethylether, dimethylacetamide, dimethylformamide and dimethylsulfoxide.
Claim 17
Dependent Claim
27 words
The process as claimed in claim 1, wherein said solidification is carried out by evaporating away said solvent from said filamentary stream of said spinning dope solution.
Claim 18
Dependent Claim
27 words
The process as claimed in claim 16, wherein before said solidification step, said spinning dope solution is extruded at a temperature of from 60° to 150° C.
Claim 19
Dependent Claim
22 words
The process as claimed in claim 16, wherein said evaporation is carried out at a temperature of from 60° to 400° C.
Claim 20
Dependent Claim
18 words
The process as claimed in claim 14, wherein said coagulation is carried out in two or more stages.
Claim 21
Dependent Claim
16 words
The process as claimed in claim 1, wherein said drawing temperature is 250° C. or more.
References Cited (Backward Citations)
SU332147A1
Cited
US3929691A
Cited
US3961009A
Cited
GB1381181A
Cited
JPS5029047A
Cited
JPS5048217A
Cited
JPS5064521A
Cited
JPS5064520A
Cited
JPS5094224A
Cited
US3985934A
Cited
US4214071A
Cited
JPS5516925A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-01-24 | 1986-07-26 | 1987-01-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-01-24 | 1990-07-26 | 1991-01-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-01-24 | 1994-07-26 | 1995-01-25 | $7700.00 | Window Closed / Lapsed |