EP0219964A1
Expired / Lapsed
EP
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Method of producing carbon fibers, and carbon fibers themselves
Assignee: Clemson University
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Filing: 1986-09-09
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Granted: —
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Expires: 2006-09-09
Abstract
Abstract Carbon fibers having a multi-lobal transverse cross-section (Figs. 7b, 7c) are produced by extruding a carbonaceous anisotropic liquid precursor through a spinneret (14) having a capillary (26) with a multi-lobal cross-section. The extruded filament is solidified in an ambient atmosphere in a quench carbinet (28) and then is rendered infusible by heating in an oven (42) in an oxygen-containing atmosphere. Thereafter, the filament is heated in an inert environment at a temperature sufficient to substantially increase the tensile strength and modulus of elasticity of the filament.
Inventors
- 👤 Danny Dale Edie
- 👤 Norman Keaton Fox
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 19:12
CPC Classifications
D; D01; D01F; D01F9/00; D01F9/08; D01F9/12; D01F9/14; D01D; D01D5/00; D01D5/253; D01F9/20; D01F9/21; D01F9/22; D01F9/32
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
105 words
A method for producing a high elastic modulus, high tensile strength carbon fiber, comprising the steps of: providing a molten precursor containing a substantial proportion of carbonaceous anisotropic material; extruding said molten precursor through a spinneret defining a capillary having at least one lobe-shaped cross-sectional area; solidifying the extruded precursor as it emerges from the spinneret, into a fiber filament having a transverse cross-section substantially like the transverse cross-section of said capillary; rendering the fiber filament infusible; and thereafter heating the fiber filament in an inert environment at a temperature sufficient to substantially increase the tensile strength and modulus of elasticity of the fiber filament.
Claim 2
Independent Claim
105 words
A method for producing a high elastic modulus, high tensile strength carbon fiber, comprising the steps of: providing a molten precursor containing a substantial proportion of carbonaceous anisotropic material; extruding said molten precursor through a spinneret defining a capillary having at least one lobe-shaped cross-sectional area; solidifying the extruded precursor as it emerges from the spinneret, into a fiber filament having a transverse cross-section substantially like the transverse cross-section of said capillary; rendering the fiber filament infusible; and thereafter heating the fiber filament in an inert environment at a temperature sufficient to substantially increase the tensile strength and modulus of elasticity of the fiber filament.
Claim 3
Dependent Claim
25 words
The method according to claim 1, wherein the step of rendering the fiber filament infusible includes heating the fiber filament in an environment including oxygen.
Claim 4
Dependent Claim
25 words
The method according to claim 1 or claim 2, wherein the step of heating the filament in an inert environment is performed in nitrogen gas.
Claim 5
Dependent Claim
38 words
The method according to claim 1, 2 or 3, wherein the spinneret defines a capillary having three lobe-shaped cross-sectional areas and the extruded fiber filament emerging from the spinneret is solidified into a fiver having a trilobal cross-section.
Claim 6
Dependent Claim
35 words
The method according to claim 4, wherein the spinneret defines a capillary having a T-shaped cross-sectional area and the extruded precursor emerging from the spinneret is solidified into a fiber filament having a T-shaped cross-section.
Claim 7
Dependent Claim
36 words
The method according to claim 4, wherein the spinneret defines a capillary having a Y-shaped cross-sectional area and the extruded precursor emerging from the spinneret is solidified into a fiber filament having a substantially Y-shaped cross-section.
Claim 8
Dependent Claim
38 words
The method according to claim 1, 2 or 3, wherein the spinneret defines a capillary having four lobe-shaped cross-sectional areas and the extruded precursor emerging from the spinneret is solidified into a fiber filament having a quadralobal cross-section.
Claim 9
Dependent Claim
38 words
The method according to claim 1, 2 or 3, wherein the spinneret defines a capillary having five lobe-shaped cross-sectional areas and the extruded precursor emerging from the spinneret is solidified into a fiber filament having a pentalobal cross-section.
Claim 10
Dependent Claim
38 words
The method according to claim 1, 2 or 3, wherein the spinneret defines a capillary having six lobe-shaped cross-sectional areas and the extruded precursor emerging from the spinneret is solidified into a fiber filament having a hexalobal cross-section.
Claim 11
Dependent Claim
38 words
The method according to claim 1, 2 or 3, wherein the spinneret defines a capillary having eight lobe-shaped cross-sectional areas and the extruded precursor emerging from the spinneret is solidified into a fiber filament having an octalobal cross-section.
Claim 12
Independent Claim
139 words
A method for producing a high elastic modulus, high tensile strength carbon fiber, comprising the steps of providing a molten precursor containing a substantial proportion of carbonaceous anisotropic material; maintaining the molten precursor at a temperature such that the viscosity of the molten precursor falls within the range between about 250 poise (25 Pa s) and a bout 2000 poise (200 Pa s); extruding said molten precursor through a spinneret defining a capillary having at least one lobe-shaped cross-sectional area; solidifying the extruded precursor as it emerges from the spinneret, into a fiber filament having a transverse cross-section substantially like the transverse cross-section of said capillary; rendering the fiber filament infusible; and thereafter heating the fiber filament in an inert environment at a temperature sufficient to substantially increase the tensile strength and modulus of elasticity of the fiber filament.
Claim 13
Independent Claim
139 words
A method for producing a high elastic modulus, high tensile strength carbon fiber, comprising the steps of providing a molten precursor containing a substantial proportion of carbonaceous anisotropic material; maintaining the molten precursor at a temperature such that the viscosity of the molten precursor falls within the range between about 250 poise (25 Pa s) and a bout 2000 poise (200 Pa s); extruding said molten precursor through a spinneret defining a capillary having at least one lobe-shaped cross-sectional area; solidifying the extruded precursor as it emerges from the spinneret, into a fiber filament having a transverse cross-section substantially like the transverse cross-section of said capillary; rendering the fiber filament infusible; and thereafter heating the fiber filament in an inert environment at a temperature sufficient to substantially increase the tensile strength and modulus of elasticity of the fiber filament.
Claim 14
Dependent Claim
21 words
A method according to claim 11, wherein the step of rendering the fiber filament infusible includes oxidation of the fiber filament.
Claim 15
Dependent Claim
34 words
A carbon fiber having at least one lobe, the or each lobe in a transverse cross-section of the fiber having a micro-structure emanating outwardly from a line extending along the length of the lobe.
Claim 16
Dependent Claim
34 words
A carbon fiber having at least one lobe, the or each lobe in a transverse cross-section of the fiber having a micro-structure emanating outwardly from a line extending along the length of the lobe.
Claim 17
Dependent Claim
19 words
A carbon fiber according to claim 13, wherein the average lobe thickness is no more than about 15 microns.
Claim 18
Dependent Claim
41 words
A carbon fiber having a multilobal cross-section, high tensile strength, high modulus of elasticity, and wherein each said lobe in a transverse cross-section of said fiber has a micro-structure emanating outwardly from a line extending along the length of the lobe.
Claim 19
Dependent Claim
41 words
A carbon fiber having a multilobal cross-section, high tensile strength, high modulus of elasticity, and wherein each said lobe in a transverse cross-section of said fiber has a micro-structure emanating outwardly from a line extending along the length of the lobe.
Claim 20
Dependent Claim
22 words
A carbon fiber according to claim 15, wherein the circumferential distance between any two adjacent lobes of the fiber is the same.
References Cited (Backward Citations)
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