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US3864626A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for evaluating properties of materials

Assignee: Celanese Corp
•
Filing: 1973-01-26
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Granted: 1975-02-04
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Expires: 1993-01-26
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Abstract

Abstract A method and apparatus are provided for nondestructively evaluating physical properties of materials, and particularly semi-conductive or electrically conductive fibers, e.g., carbonaceous fibrous materials containing at least about 90 per cent carbon by weight. The material is disposed in spaced relationship to a test electrode in an electrolytic solution and the physical property of the fiber is evaluated by evaluating the capacitance of the material. This capacitance evaluation may then be compared to the capacitance evaluation of a reference material having predetermined physical properties with the results of the comparison indicating the properties of the tested material. This indication may be utilized in the quality control of manufactured fibers by manual or automatic adjustment of the manufacturing process conditions. In fiber experimentation, this indication may be utilized to provide an evaluation of the effectiveness of an experimental process.

Inventors

  • 👤 Alexander F Maclean
  • 👤 Ilmar L Kalnin

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 09:54
CPC Classifications
G; G01; G01R; G01R27/00; G01R27/02; G01R27/26; G01R27/2605; B; B29; B29C; B29C48/00; B29C48/02; B29C48/25; B29C48/92; G01N; G01N27/00; G01N27/02; G01N27/22; B29C2948/00; B29C2948/92; B29C2948/92009; B29C2948/92238; B29C2948/92323; B29C2948/92485; B29C2948/92504; B29C48/03; B29C48/05

Claims Analysis

Total Claims: 28
Claim 1
Independent Claim 116 words
A method for evaluating a physical property of a carbonaceous fibrous material containing at least about 90 per cent carbon by weight comprising the steps of: a. providing an electrolyte and a counter electrode in contact with the electrolyte; b. disposing the carbonaceous fibrous material to be evaluated in contact with the electrolyte at a predetermined distance from the counter electrode; c. applying an electrical potential of known amplitude between the counter electrode and the carbonaceous fibrous material through a reference capacitor having a known value; d. sensing the amplitude of an output potential across the reference capacitor; and e. evaluating a physical property of the carbonaceous fibrous material as a function of the sensed amplitude.
Claim 2
Independent Claim 116 words
A method for evaluating a physical property of a carbonaceous fibrous material containing at least about 90 per cent carbon by weight comprising the steps of: a. providing an electrolyte and a counter electrode in contact with the electrolyte; b. disposing the carbonaceous fibrous material to be evaluated in contact with the electrolyte at a predetermined distance from the counter electrode; c. applying an electrical potential of known amplitude between the counter electrode and the carbonaceous fibrous material through a reference capacitor having a known value; d. sensing the amplitude of an output potential across the reference capacitor; and e. evaluating a physical property of the carbonaceous fibrous material as a function of the sensed amplitude.
Claim 3
Dependent Claim 17 words
The method of claim 1 wherein said carbonaceous fibrous material exhibits a predominantly graphitic x-ray diffraction patteRn.
Claim 4
Dependent Claim 31 words
The method of claim 1 including the further step of wetting the carbonaceous fibrous material in a wetting solution prior to disposing the carbonaceous fibrous material in contact with the electrolyte.
Claim 5
Dependent Claim 45 words
The method of claim 3 including the steps of: a. disposing a reference electrode in contact with the electrolyte and spaced from the counter electrode and the carbonaceous fibrous material; and b. applying a predetermined bias potential between the reference electrode and the counter electrode.
Claim 6
Dependent Claim 31 words
The method of claim 4 wherein the electrical potential is applied between the carbonaceous fibrous material and the counter electrode periodically at a rate of at least 10 pulses per minute.
Claim 7
Dependent Claim 49 words
The method of claim 1 including: a. dividing the sensed amplitude by a property of the carbonaceous fiber related to the fiber weight or size to obtain a normalized evaluation; and b. comparing the normalized evaluation with a normalized evaluation of a reference fiber to obtain a relative evaluation.
Claim 8
Independent Claim 98 words
A method for evaluating a relative physical property of a carbonaceous fibrous material containing at least about 90 per cent carbon by weight comprising the steps of: a. disposing a predetermined portion of the carbonaceous fibrous material in spaced relation to an electrode; b. immersing the spaced carbonaceous fibrous material and electrode in an electrolytic solution to form an electrolytic cell having spaced electrodes; c. sensing the capacitance between the carbonaceous fibrous material and the electrode in the electrolytic cell; and d. evaluating a physical property of the carbonaceous fibrous material as a function of the sensed capacitance.
Claim 9
Independent Claim 98 words
A method for evaluating a relative physical property of a carbonaceous fibrous material containing at least about 90 per cent carbon by weight comprising the steps of: a. disposing a predetermined portion of the carbonaceous fibrous material in spaced relation to an electrode; b. immersing the spaced carbonaceous fibrous material and electrode in an electrolytic solution to form an electrolytic cell having spaced electrodes; c. sensing the capacitance between the carbonaceous fibrous material and the electrode in the electrolytic cell; and d. evaluating a physical property of the carbonaceous fibrous material as a function of the sensed capacitance.
Claim 10
Independent Claim 89 words
A method of evaluating a surface characteristic of a carbonaceous fibrous material containing at least about 90 per cent carbon by weight comprising the steps of: a. providing an elongated electrode; b. disposing the carbonaceous fibrous material in a spaced relation to the electrode; c. applying an unidirectional current pulse to either one of the fibrous material and the electrode; d. sensing the current on the other of the carbonaceous fibrous material and the electrode; and e. evaluating the current sensed as the surface characteristic of the fibrous material.
Claim 11
Independent Claim 89 words
A method of evaluating a surface characteristic of a carbonaceous fibrous material containing at least about 90 per cent carbon by weight comprising the steps of: a. providing an elongated electrode; b. disposing the carbonaceous fibrous material in a spaced relation to the electrode; c. applying an unidirectional current pulse to either one of the fibrous material and the electrode; d. sensing the current on the other of the carbonaceous fibrous material and the electrode; and e. evaluating the current sensed as the surface characteristic of the fibrous material.
Claim 12
Dependent Claim 17 words
The method of claim 8 wherein the carbonaceous fibrous material exhibits a predominantly graphitic x-ray diffraction pattern.
Claim 13
Independent Claim 91 words
A method for determining a relative physical property of a fiber comprising the steps of: a. sensing the capacitance of a capacitive cell having two electrodes and having a reference fiber of known physical properties as one of the electrodes; b. sensing the capacitance of said capacitive cell having a second fiber of unknown physical properties as said one of the electrodes; and c. evaluating an unknown physical property of the second fiber relative to a known physical property of the reference fiber as a function of the two sensed capacitances.
Claim 14
Independent Claim 91 words
A method for determining a relative physical property of a fiber comprising the steps of: a. sensing the capacitance of a capacitive cell having two electrodes and having a reference fiber of known physical properties as one of the electrodes; b. sensing the capacitance of said capacitive cell having a second fiber of unknown physical properties as said one of the electrodes; and c. evaluating an unknown physical property of the second fiber relative to a known physical property of the reference fiber as a function of the two sensed capacitances.
Claim 15
Independent Claim 96 words
A method for evaluating a physical property of a continuous length of a carbonaceous fibrous material containing at least about 90 per cent carbon by weight comprising the steps of: a. providing an enclosure containing an electrolyte and a counter electrode in contact therewith; b. passing the continuous length of carbonaceous fibrous material as a continuous test electrode in contact with the electrolyte present in said enclosure at a predetermined distance from the counter electrode; and c. sensing the capacitance between the counter electrode and the fibrous material as the fibrous material passes through the electrolyte.
Claim 16
Independent Claim 96 words
A method for evaluating a physical property of a continuous length of a carbonaceous fibrous material containing at least about 90 per cent carbon by weight comprising the steps of: a. providing an enclosure containing an electrolyte and a counter electrode in contact therewith; b. passing the continuous length of carbonaceous fibrous material as a continuous test electrode in contact with the electrolyte present in said enclosure at a predetermined distance from the counter electrode; and c. sensing the capacitance between the counter electrode and the fibrous material as the fibrous material passes through the electrolyte.
Claim 17
Dependent Claim 45 words
The method of claim 11 including the steps of: a. disposing a reference electrode in contact with the electrolyte and spaced from the counter electrode and the carbonaceous fibrous material; and b. applying a predetermined bias potential between the reference electrode and the counter electrode.
Claim 18
Dependent Claim 30 words
The method of claim 12 including the further step of wetting the carbonaceous fibrous material in a wetting solution prior to disposing the fibrous material in contact with the electrolyte.
Claim 19
Dependent Claim 30 words
The method of claim 11 including the further step of wetting the carbonaceous fibrous material in a wetting solution prior to disposing the fibrous material in contact with the electrolyte.
Claim 20
Dependent Claim 78 words
Apparatus for evaluating a physical property of a fiber having an electrically conductive outer surface comprising: a test electrode disposed in spaced relation to the fiber being evaluated; an electrolyte intermediate the test electrode and the fiber and in contact with both the test electrode and the electrically conductive surface of the fiber to thereby form an electrolytic cell; and means for sensing the capacitance of the electrolytic cell to thereby evaluate a physical property of the fiber.
Claim 21
Dependent Claim 78 words
Apparatus for evaluating a physical property of a fiber having an electrically conductive outer surface comprising: a test electrode disposed in spaced relation to the fiber being evaluated; an electrolyte intermediate the test electrode and the fiber and in contact with both the test electrode and the electrically conductive surface of the fiber to thereby form an electrolytic cell; and means for sensing the capacitance of the electrolytic cell to thereby evaluate a physical property of the fiber.
Claim 22
Dependent Claim 65 words
The apparatus of claim 15 wherein said sensing means comprises: a reference capacitor; means for periodically applying an electrical potential through the reference capacitor to one of the test electrodes and the fiber; means for sensing the potential across the reference capacitor; and means for providing an indication of the capacitance of the cell in response to the applied electrical potential and the sensed potential.
Claim 23
Dependent Claim 24 words
The apparatus of claim 16 including: a reference electrode; and means for applying a bias potential between the reference electrode and the test electrode.
Claim 24
Dependent Claim 43 words
The apparatus of claim 16 wherein the fiber comprises a carbonaceous fibrous material containing at least 90 per cent carbon by weight and means for moving the fibrous material through the electrolyte in contact therewith and in spaced relation to the test electrode.
Claim 25
Dependent Claim 19 words
The apparatus of claim 18 including a wetting solution for wetting the fibrous material prior to contacting the electrolyte.
Claim 26
Dependent Claim 145 words
Apparatus for evaluating a physical property of a carbonaceous fibrous material containing at least about 90 per cent carbon by weight comprising: a container provided with an electrolytic solution; a test electrode disposed within said container in contact with the electrolyte; a carbonaceous fibrous material disposed within said container in spaced relation to the test electrode, at least a portion of said carbonaceous fibrous material being in contact with the electrolyte; a reference capacitor; means for periodically applying an electrical potential through said reference capacitor to one of said test electrodes and said carbonaceous fibrous material; means for sensing one of the potential developed between said test electrode and said carbonaceous fibrous material and the potential across said reference capacitor; and means for evaluating a surface property of the carbonaceous fibrous material in response to the magnitudes of the applied potential and the sensed potential.
Claim 27
Dependent Claim 145 words
Apparatus for evaluating a physical property of a carbonaceous fibrous material containing at least about 90 per cent carbon by weight comprising: a container provided with an electrolytic solution; a test electrode disposed within said container in contact with the electrolyte; a carbonaceous fibrous material disposed within said container in spaced relation to the test electrode, at least a portion of said carbonaceous fibrous material being in contact with the electrolyte; a reference capacitor; means for periodically applying an electrical potential through said reference capacitor to one of said test electrodes and said carbonaceous fibrous material; means for sensing one of the potential developed between said test electrode and said carbonaceous fibrous material and the potential across said reference capacitor; and means for evaluating a surface property of the carbonaceous fibrous material in response to the magnitudes of the applied potential and the sensed potential.
Claim 28
Dependent Claim 33 words
The apparatus of claim 20 including: a reference electrode disposed within said container in contact with the electrolyte; and means for applying a bias potential between said reference electrode and said test electrode.

References Cited (Backward Citations)

US2966628A Cited
US2942181A Cited
US3371568A Cited
US3778705A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-02-03 1978-08-05 1979-02-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-02-03 1982-08-05 1983-02-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-02-03 1986-08-05 1987-02-04 $7700.00 Window Closed / Lapsed

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