CN106596614A - Polyacrylonitrile preoxidized fiber skin-core structure detection method - Google Patents
Polyacrylonitrile preoxidized fiber skin-core structure detection method Download PDFInfo
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- CN106596614A CN106596614A CN201611114005.2A CN201611114005A CN106596614A CN 106596614 A CN106596614 A CN 106596614A CN 201611114005 A CN201611114005 A CN 201611114005A CN 106596614 A CN106596614 A CN 106596614A
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- core
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- oxidized fibers
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N23/00—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00
- G01N23/22—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by measuring secondary emission from the material
- G01N23/225—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by measuring secondary emission from the material using electron or ion
- G01N23/2251—Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by measuring secondary emission from the material using electron or ion using incident electron beams, e.g. scanning electron microscopy [SEM]
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
- G01N1/286—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q involving mechanical work, e.g. chopping, disintegrating, compacting, homogenising
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
- G01N1/44—Sample treatment involving radiation, e.g. heat
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N1/00—Sampling; Preparing specimens for investigation
- G01N1/28—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
- G01N1/286—Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q involving mechanical work, e.g. chopping, disintegrating, compacting, homogenising
- G01N2001/2873—Cutting or cleaving
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Abstract
A polyacrylonitrile preoxidized fiber skin-core structure detection method includes impregnating preoxidized short fibers in a sulfuric acid solution, heating to be boiling, performing refluxing treatment for 0.1-2 hours, washing the treated sample to be neutral, drying the washed sample, and cooling the dried sample to the room temperature; scanning the sections of the treated preoxidized short fibers by an SEM, storing pictures, subjecting the pictures to fiber diameter and core diameter measurement by SEM measuring software, averaging, and determining the core proportion. The polyacrylonitrile preoxidized fiber skin-core structure detection method is simple and convenient to operate and capable of detecting a PAN (polyacrylonitrile) preoxidized fiber skin-core structure accurately and quickly.
Description
Technical field
A kind of method of degree the invention belongs to detection polyacrylonitrile (PAN) pre-oxidized fibers homogenize, more particularly to one
Plant the detection method of pre-oxidized fibers skin-core structure.
Background technology
Carbon fiber has the excellent properties such as high specific strength, high ratio modulus, corrosion-resistant, high temperature resistant, rub resistance, heat conduction, conduction,
Have a wide range of applications in fields such as Aero-Space, physical culture, building, automobile, new forms of energy.In the preparation process of PAN base carbon fibres
In, pre-oxidation treatment is to affect one of key link of carbon fiber performance, plays a part of to form a connecting link, makes plasticity PAN line
Property strand there is the reaction such as intramolecular cyclization, intermolecular cross-linking and oxidation, be converted into nonplastic heat-resisting trapezium structure.Here mistake
Cheng Zhong, due to fibrous outer, quickly cyclisation forms compact texture, hinders transmission of the oxygen along fiber radially inward portion, so that fine
Dimension outer layer and internal preoxidation degree have differences, and the difference of this seed coat layer and internal preoxidation degree is skin-core structure.
During follow-up low-temperature carbonization, the relatively low core of preoxidation degree produces that lysate is more, and the defect of formation is more, most shadow at last
Ring the performance of carbon fiber.The skin-core structure of regulation and control pre-oxidized fibers homogenizes degree, is conducive to further lifting carbon fiber
Performance.Therefore, a kind of method for quick and precisely detecting pre-oxidized fibers skin-core structure is invented, the tune of pre-oxidation process parameter is instructed
It is whole, have very important significance.Zhu little Long (CN103575754A), should using SEM observation measurement methods after sulfuric acid solution etching
Method first solidifies pre-oxidized fibers with collodion, is then cut off along fixture with blade, then is etched with room temperature sulfuric acid solution, here mistake
As pre-oxidized fibers toughness is larger in journey, collodion solidification effect is poor, when being cut with blade fiber easily lodge, section not
It is smooth；Core is etched with sulfuric acid solution again after knife cutting sample, easily makes that fibre section is not bright and clean, hole wall is rough, affect observation
And the accuracy of core diameters measurement result.Qi Ming its (CN101825558A) adopts optical densitometric method, but the method firstly the need of
Process through the ultrathin section of strict 50-1500nm thickness or so, and need to ensure that tangent plane is smooth without tool marks, next also needs to
The graphical analyses that gained picture carries out specialty are just obtained into data, disposed of in its entirety step is complicated, operation difficulty is high.
Therefore, the detection urgent need of PAN pre-oxidized fibers skin-core structure is a kind of easy to operate, quick and precisely can tie feedback test
The method of fruit, the application of this method can be the adjustment of pre-oxidation process parameter in industrialized production, there is provided directly perceived, quantitative
Instruct.
The content of the invention
It is an object of the invention to provide it is a kind of easy to operate, can fast and accurately detect that PAN pre-oxidized fibers core-skin is tied
The method of structure.
The present invention provides a kind of detection method of PAN pre-oxidized fibers skin-core structure, comprises the following steps：
(1) 0.5-2g PAN pre-oxidized fibers long filaments are cut to the short silk of 2-4cm, the flask for filling sulfuric acid solution is impregnated in
In, sulfuric acid solution concentration is 20-60wt%, sulfuric acid solution is heated to boiling, and is flowed back, by pre- oxygen under the conditions of boiling
Change fiber treatment 0.1-2h；
(2) the pre-oxidized fibers being disposed are taken out, and deionized water agitator treating to neutrality, filter paper are collected in after filtering
In surface plate；
(3) by the sample collected, 1-2h is dried at 100-140 DEG C, insert after taking-up
Temperature；
(4) the short silk of pre-oxidized fibers after step (3) is processed is taken, will be placed in parallel between pre-oxidized fibers short silk, it is double with bar shaped
Pre-oxidized fibers short silk is tightly wound by face conductive tape, then the two ends of wound adhesive tape are quickly cut off with blade, retains middle
Its one end is cemented with two-sided conductive tape and is stood on SEM sample bench by a section of 0.5cm length, fine with SEM scanning pre-oxidation
Figure is deposited simultaneously in dimension section；
(5) picture is carried out with the Survey Software of SEM the measurement of fiber and core diameters, is calculated and determined with equation below
Core ratio：
Core ratio/%=(RCore diameters/RPre-oxidized fibers diameter)2× 100%；
(6) 5 its diameters of fiber measurement and core diameters in picture are arbitrarily chosen, calculates core ratio respectively, finally
Average, determine core proportion.
PAN pre-oxidized fibers as above are the PAN pre-oxidation of 1K (1K=1000 root fibers), 3K, 6K, 12K, 24K
Fiber.
The invention has the advantages that：
Compared with prior art, present invention operation is easier.The present invention is in the sulfuric acid solution of boiling to process pre- oxygen
Chemical fibre is tieed up, even if can equally ensure treatment effeciency and effect in low-concentration sulfuric acid solution.After the processing of the method, pre-oxidize fine
Dimension only remains cortex construction, and toughness is reduced beneficial to knife cutting sample, then after being tightly fastened with conductive tape, is avoided that substantially knife is cut
During fiber lodging phenomenon, and the flatness in section can be ensured；It is exactly pre-oxidized fibers that Jing the method was processed to have again
Section hole is obvious, hole wall is smooth, beneficial to observation and the measurement of core diameters.
Description of the drawings
Fig. 1 is the pre-oxidized fibers Cross Section Morphology of 20wt% sulfuric acid solutions 2h.
Fig. 2 is the pre-oxidized fibers Cross Section Morphology of 40wt% sulfuric acid solutions 0.8h.
Fig. 3 is the pre-oxidized fibers Cross Section Morphology of 60wt% sulfuric acid solutions 0.1h.
It is embodied as example
The following detailed description of the present invention and provide several embodiments and comparative example：
Embodiment 1
The short silk of 1KPAN pre-oxidized fibers of 1g3cm length is impregnated in the flask for filling sulfuric acid solution, sulfuric acid solution is dense
Spend for 20wt%, sulfuric acid solution is heated to into boiling, process time 2h.By the pre-oxidized fibers handled well short silk, filling
In the beaker of ionized water, agitator treating collects pre-oxidized fibers to neutrality to remove the sulfuric acid solution of residual, after being filtered with filter paper
Short silk in surface plate is dried 1.5h at 120 DEG C in being put into air dry oven, and room temperature is naturally cooled in exsiccator.Take
The short silk of pre-oxidized fibers after process, will be placed in parallel between pre-oxidized fibers short silk, with the two-sided conductive tape of bar shaped by pre- oxygen
Change short fibre tightly to wind, then the two ends of wound adhesive tape are quickly cut off with blade, retain a section of middle 0.5cm length, will
The two-sided conductive tape of its one end is cemented and is stood on SEM sample bench, is scanned pre-oxidized fibers section with SEM and is deposited figure, such as
Shown in accompanying drawing 1.5 fibers in picture are chosen arbitrarily, Survey Software is carried with SEM carries out the measurement of fiber and core diameters,
Core ratio is calculated with equation below：
Core ratio/%=(RCore diameters/RPre-oxidized fibers diameter)2× 100%
Calculated shared by 5 fiber cores respectively, acquired results ratio is averaged, final result is shown in Table 1.
Comparative example 1
In order to verify that SEM carries the accuracy of software measurement, autodesk, inc. can be utilized after SEM micrograph piece is obtained
AutoCAD softwares, using with embodiment 1 in identical computing formula and method can obtain core proportion in embodiment 1,
Final result is shown in Table 1.
Embodiment 2
The short silk of 3KPAN pre-oxidized fibers of 1g3cm length is impregnated in the flask for filling sulfuric acid solution, sulfuric acid solution is dense
Spend for 40wt%, sulfuric acid solution is heated to into boiling, process time 0.8h.By the pre-oxidized fibers handled well short silk, filling
In the beaker of deionized water, agitator treating collects pre-oxidation fine to neutrality to remove the sulfuric acid solution of residual, after being filtered with filter paper
Short silk is tieed up in surface plate, 1.5h is dried at 120 DEG C in being put into air dry oven, and room temperature is naturally cooled in exsiccator.
The short silk of pre-oxidized fibers after processing is taken, will be placed in parallel between pre-oxidized fibers short silk, will be pre- with the two-sided conductive tape of bar shaped
The short silk of oxidized fibre tightly winds, then the two ends of wound adhesive tape are quickly cut off with blade, retains a section of middle 0.5cm length,
Its one end is cemented with two-sided conductive tape and is stood on SEM sample bench, pre-oxidized fibers section is scanned with SEM and is deposited figure,
As shown in Figure 2.5 fibers in picture are chosen arbitrarily, Survey Software is carried with SEM carries out the survey of fiber and core diameters
Amount, calculates core ratio with equation below：
Core ratio/%=(RCore diameters/RPre-oxidized fibers diameter)2× 100%
Calculated shared by 5 fiber cores respectively, acquired results ratio is averaged, final result is shown in Table 1.
Comparative example 2
Core proportion in embodiment 2 can be obtained using with 1 identical Survey Software of comparative example and method, final result is shown in
Table 1.
Embodiment 3
The short silk of 6KPAN pre-oxidized fibers of 1g3cm length is impregnated in the flask for filling sulfuric acid solution, sulfuric acid solution is dense
Spend for 60wt%, sulfuric acid solution is heated to into boiling, process time 0.1h.By the pre-oxidized fibers handled well short silk, filling
In the beaker of deionized water, agitator treating collects pre-oxidation fine to neutrality to remove the sulfuric acid solution of residual, after being filtered with filter paper
Short silk is tieed up in surface plate, 1.5h is dried at 120 DEG C in being put into air dry oven, and room temperature is naturally cooled in exsiccator.
The short silk of pre-oxidized fibers after processing is taken, will be placed in parallel between pre-oxidized fibers short silk, will be pre- with the two-sided conductive tape of bar shaped
The short silk of oxidized fibre tightly winds, then the two ends of wound adhesive tape are quickly cut off with blade, retains a section of middle 0.5cm length,
Its one end is cemented with two-sided conductive tape and stood on SEM sample bench, pre-oxidized fibers Cross Section Morphology is scanned with SEM and is deposited
Figure, as shown in Figure 3.5 fibers in picture are chosen arbitrarily, Survey Software is carried with SEM carries out fiber and core diameters
Measurement, calculates core ratio with equation below：
Core ratio/%=(RCore diameters/RPre-oxidized fibers diameter)2× 100%
Calculated shared by 5 fiber cores respectively, acquired results ratio is averaged, final result is shown in Table 1.
Comparative example 3
Core proportion in embodiment 3 can be obtained using with 1 identical Survey Software of comparative example and method, final result is shown in
Table 1
By embodiment 1-3, comparative example 1-3 and table 1 understand, carry test result obtained by software using SEM accurate.And by
Embodiment 1-3 understands, the pre-oxidized fibers of same preoxidation degree, using the boiling sulfuric acid solution of variable concentrations, finally
Treatment effect is essentially identical, but high-concentration sulfuric acid solution can save process time.
1 pre-oxidized fibers core proportion of table
Claims (2)
1. a kind of detection method of pre-oxidized polyacrylonitrile fiber skin-core structure, it is characterised in that comprise the steps：
（1）0.5-2g PAN pre-oxidized fibers long filaments are cut to into the short silk of 2-4cm, be impregnated in the flask for filling sulfuric acid solution,
Sulfuric acid solution concentration is 20-60wt%, sulfuric acid solution is heated to boiling, and is flowed back, will be pre-oxidation fine under the conditions of boiling
Dimension processes 0.1-2h；
（2）The pre-oxidized fibers that taking-up is disposed, deionized water agitator treating to neutrality, filter paper are collected in surface after filtering
In ware；
（3）By the sample collected, 1-2 h are dried at 100-140 DEG C, is inserted after taking-up in exsiccator and is naturally cooled to room
Temperature；
（4）Take step（3）The short silk of pre-oxidized fibers after process, will be placed in parallel between pre-oxidized fibers short silk, two-sided with bar shaped
Pre-oxidized fibers short silk is tightly wound by conductive tape, then the two ends of wound adhesive tape are quickly cut off with blade, retains middle
Its one end is cemented with two-sided conductive tape and is stood on SEM sample bench by a section of 0.5cm length, fine with SEM scanning pre-oxidation
Figure is deposited simultaneously in dimension section；
（5）Picture is carried out into the measurement of fiber and core diameters with the Survey Software of SEM, core is calculated and determined with equation below
Ratio：
Core ratio/%=（RCore diameters/RPre-oxidized fibers diameter）2×100%；
（6）5 its diameters of fiber measurement and core diameters in picture are arbitrarily chosen, core ratio is calculated respectively, is finally made even
Average, determines core proportion.
2. a kind of detection method of pre-oxidized polyacrylonitrile fiber skin-core structure as claimed in claim 1, it is characterised in that institute
Pre-oxidized polyacrylonitrile fiber of the pre-oxidized polyacrylonitrile fiber stated for 1K, 3K, 6K, 12K or 24K.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107478545A (en) * | 2017-08-15 | 2017-12-15 | 兰州蓝星纤维有限公司 | A kind of assay method of carbon fibre precursor adhesion number |
| CN111562279A (en) * | 2020-05-11 | 2020-08-21 | 江苏恒神股份有限公司 | Characterization method of skin-core structure of pre-oxidized fiber |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101949827A (en) * | 2010-09-16 | 2011-01-19 | 中国科学院西安光学精密机械研究所 | Quantitative testing method of skin-core structure of carbon fibers |
| CN102169096A (en) * | 2010-12-22 | 2011-08-31 | 中国科学院山西煤炭化学研究所 | Method for detecting shape and appearance of section of polyacrylonitrile-based precursor, and clamp |
| CN103575754A (en) * | 2012-07-20 | 2014-02-12 | 中国科学院宁波材料技术与工程研究所 | Determination method of carbon fiber pre-oxidized fiber skin-core structure |
-
2016
- 2016-12-07 CN CN201611114005.2A patent/CN106596614A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101949827A (en) * | 2010-09-16 | 2011-01-19 | 中国科学院西安光学精密机械研究所 | Quantitative testing method of skin-core structure of carbon fibers |
| CN102169096A (en) * | 2010-12-22 | 2011-08-31 | 中国科学院山西煤炭化学研究所 | Method for detecting shape and appearance of section of polyacrylonitrile-based precursor, and clamp |
| CN103575754A (en) * | 2012-07-20 | 2014-02-12 | 中国科学院宁波材料技术与工程研究所 | Determination method of carbon fiber pre-oxidized fiber skin-core structure |
Non-Patent Citations (2)
| Title |
|---|
| 江驰等: "硫酸处理聚丙烯腈预氧化纤维的研究", 《合成纤维工业》 * |
| 王雪飞等: "聚丙烯腈热稳定化纤维径向非均质结构的表征和调控", 《化工新型材料》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107478545A (en) * | 2017-08-15 | 2017-12-15 | 兰州蓝星纤维有限公司 | A kind of assay method of carbon fibre precursor adhesion number |
| CN111562279A (en) * | 2020-05-11 | 2020-08-21 | 江苏恒神股份有限公司 | Characterization method of skin-core structure of pre-oxidized fiber |
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Application publication date: 20170426 |