CN101165072B - Method for removing alkali metal impurity in polyacrylonitrile resin - Google Patents
Method for removing alkali metal impurity in polyacrylonitrile resin Download PDFInfo
- Publication number
- CN101165072B CN101165072B CN2006101172439A CN200610117243A CN101165072B CN 101165072 B CN101165072 B CN 101165072B CN 2006101172439 A CN2006101172439 A CN 2006101172439A CN 200610117243 A CN200610117243 A CN 200610117243A CN 101165072 B CN101165072 B CN 101165072B
- Authority
- CN
- China
- Prior art keywords
- polyacrylonitrile resin
- alkali metal
- metal impurity
- polyacrylonitrile
- acid
- 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.)
- Active
Links
Landscapes
- Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
Abstract
The process of eliminating alkali metal impurity from polyacrylonitrile resin includes the following steps: soaking the resin in deionized water at 20-50 deg.c to swell for 1-2.5 hr; acid washing resin in water solution of nitric acid or hydrochloric acid of pH 0.1-3.0 at 25-60 deg.c for 0.5-1.5 hr, with the weight ratio between resin and water solution of acid being 1 to 4-20; rinsing resin with deionized water at 25-60 deg.c to neutrality; dewatering and drying. The process can eliminate alkali metal impurity from polyacrylonitrile resin effectively, and the purified polyacrylonitrile resin may be applied in preparing polyacrylonitrile yarn for high purity carbon fiber.
Description
Technical field
The present invention relates to a kind of method of removing alkali metal impurity in the polyacrylonitrile resin, polyacrylonitrile resin is used to make polyacrylonitrile base carbon fiber precursors with the aqueous suspension polymerization prepared.
Background technology
Carbon fiber has excellent mechanical characteristics, and other material of specific tenacity that it is high and specific modulus hardly matches, and as a kind of strongthener, it is widely used in the fields such as manufacturing of space flight, flyer and sports equipment.Carbon fiber is made after preoxidation and carbonization by the precursor that carbonizable substance is made usually, because polyacrylonitrile resin has higher carbonization yield, therefore polyacrylonitrile fibre is unusual ideal carbon fibre precursor, and the carbon fiber that makes thus is called PAN-based carbon fiber.Obtain the carbon fiber of excellent property, the high purifying of precursor is most important.Since metal species impurity after the pyroprocessing of preoxidation and carbonization still the form with oxide compound be present in the carbon fiber, so relative non-metal kind impurity, metal species impurity is even more serious to the influence of final carbon fiber product mechanical property.The impurity of basic metal class particularly, they have katalysis to the oxidation of carbon, carry out high temperature such as preoxidation, carbonization at precursor when handling, and can promote CO, CO
2Thereby the effusion Deng gas forms cavity blemish in carbon fiber inside.Ash can reflect metallic impurity total content in the precursor indirectly, when ash is lower than 0.1 ‰, is generally considered to be high purifying and the content of alkalimetal ion is no more than 0.05 ‰ o'clock precursor, and the carbon fiber that makes thus will have higher quality.
Metal species impurity in the polyacrylonitrile base carbon fiber precursors can be from the solvent of polymer raw, polymerization initiation system and polymerization or spinning.In the prior art for the common way of the removal of metal species impurity be last handling process, the precursor of precursor spinning make the back or precursor pre-oxidation after etc. link wash, United States Patent (USP) U.S 4388289 has promptly introduced part technology wherein, and these existing washing means are considered to effective for the impurity from polymer raw and polymerization or spin solvent.And it is generally acknowledged from the difficult method by washing of the impurity of polymerization initiation system and remove, because of they are present on the molecular chain of polymkeric substance, but be the polymer molecule interchain that is present in the fiber surface of precursor or fibrous inside from the impurity of polymer raw and polymerization or spin solvent.
The same with the manufacturing of common acrylic fibers, polyacrylonitrile base carbon fiber precursors can adopt the method manufacturing of single stage method, i.e. same solvent is adopted in polymerization and spinning, and polymeric reaction solution directly carries out spinning after regulating concentration; Also can adopt and use the two-step approach manufacturing, promptly carry out the preparation of polyacrylonitrile resin earlier, technology commonly used is aqueous suspension polymerization, and the polyacrylonitrile resin that obtains is made spinning solution with solvent again and carried out spinning.Because the polymerization process of two-step approach generally adopts redox system, their majorities contain alkali metal, and the polymerization process of single stage method can adopt azo class initiator system, so polyacrylonitrile base carbon fiber precursors adopts the method manufacturing of single stage method basically in the prior art, its objective is in the polymer molecular chain of avoiding precursor to be introduced into alkali metal.But single stage method requires from being polymerized to the production line that spinning forms continuous whole, and this makes the quality control of precursor product and the handiness of production etc. can not show a candle to two-step approach.In the industrial production of common acrylic fibers, single stage method also is used for making on a large scale conventional variety more.With regard to technological process, two-step approach obviously is more suitable for the manufacturing in polyacrylonitrile base carbon fiber precursors, just at present still lacks effectively for the removal that is derived from polymerization initiation system impurity in the spinning material polyacrylonitrile resin and is easy to industrialized means.
Summary of the invention
The invention provides a kind of method of removing alkali metal impurity in the polyacrylonitrile resin, this method can be removed the basic metal class impurity that is derived from initiator system in the resin effectively, thereby makes the polyacrylonitrile resin that is made by aqueous suspension polymerization technology can be used as the spinning material that two-step approach solvent spinning technology is made high purifying polyacrylonitrile base carbon fiber precursors.
Below be the detailed technical scheme of the present invention:
A kind of method of removing alkali metal impurity in the polyacrylonitrile resin, it may further comprise the steps successively:
1) polyacrylonitrile resin places deionized water to soak swelling 1～2.5 hour, and water temperature is controlled to be 20～50 ℃;
2) polyacrylonitrile resin is placed aqueous acid impose stirring and carry out pickling, nitric acid or hydrochloric acid are adopted in acid, and the pH value of aqueous acid is 0.1～3.0, and the weight ratio of polyacrylonitrile resin and aqueous acid is 1: (4～20), pickling temperature is 25～60 ℃, and the pickling time is 0.5～1.5 hour;
3) polyacrylonitrile resin is extremely neutral with rinsed with deionized water, rinsing temperature is 25～60 ℃;
4) polyacrylonitrile resin is dewatered and is dry.
Above-mentioned steps 1 described water temperature preferably is controlled to be 30～40 ℃.
The pH value of above-mentioned steps 2 described aqueous acids is preferably 0.3～1.6; The weight ratio of polyacrylonitrile resin and salpeter solution is preferably 1: (4～12); Pickling temperature is preferably 35～45 ℃.
Above-mentioned steps 3 described rinsing temperatures are preferably 40～50 ℃.
In the technical program, polyacrylonitrile resin makes with aqueous suspension polymerization technology, the polymeric initiator is water miscible Oxidizing and Reducing Agents, and wherein oxygenant is a kind of in ammonium persulphate, Potassium Persulphate, hydrogen peroxide or the sodium chlorate, or two or more mixtures; Reductive agent is a kind of in Sodium Pyrosulfite, sodium bisulfite or the S-WAT, or two or more mixtures.
The same with prior art, above-mentioned polyacrylonitrile resin is the multipolymer of vinyl cyanide and other vinyl monomer, vinyl cyanide generally is at least 95wt% in the comonomer, other monomer comprises the first comonomer and second comonomer, its effect is respectively drawing-off property modification and stabilizing modification, the former can be methyl acrylate, ethyl propenoate, methyl methacrylate, Jia Jibingxisuanyizhi or vinyl acetate etc., and the latter can be methacrylic acid, vinylformic acid, methylene-succinic acid, acrylamide or Methacrylamide etc.
Although being derived from the alkali metal impurity of initiator system is present in the polyacrylonitrile molecular chain, but be positioned at the end of the chain of molecular chain after all, theoretically, this is positioned at the molecular chain middle part than impurity removes easily, and the structure of molecular chain can not destroyed because of the removal of impurity yet.Key of the present invention is the design of washing process.The polyacrylonitrile resin that is obtained by aqueous polymerization is powdery, and bigger specific surface is obviously favourable to washing, but also is easy to generate negative influence simultaneously.Therefore the design of washing process just seems extremely important, comprise washing and pickling the mode that hockets, sour selection, wash condition of each step or the like.If acid intensity, wash temperature and time etc. of acidic cleaning liquid are integrated are interpreted as washing intensity, then crossing in the low washing intensity precursor may still remaining more alkali metal impurity, and the washing intensity too high polyacrylonitrile resin that may make is partly dissolved, even causes the polyacrylonitrile resin molecule oxidized etc.By a large amount of experiments, the contriver has determined the washing strength range described in the technique scheme, and experimental data shows, can remove alkali metal impurity effectively in the washing that this scope is carried out, and can guarantee that polyacrylonitrile resin does not take place by dissolving or not oxidized, the destruction that perhaps suffers other form.
It is that solvent is made spinning solution that polyacrylonitrile resin after the washing can adopt organic solvents such as dimethyl sulfoxide (DMSO) or dimethyl formamide, and also can adopt the NaSCN aqueous solution is solvent.Spinning process adopts conventional wet processing, and the last handling process of nascent fibre is also basic identical with prior art.Solvent preferably adopts the not organic solvent of containing metal element, the metal species impurity that can avoid spinning process to be brought by solvent like this.When adopting the NaSCN aqueous solution to be solvent, can be in the last handling process of nascent fibre remove in the fiber alkali metal impurity by pickling again from solvent and spinning process.
Compared with prior art, advantage of the present invention be washing methods very effectively and be easy to industrialization, can remove the alkali metal impurity that is derived from initiator system in the resin more up hill and dale, thereby make the polyacrylonitrile resin that makes by aqueous suspension polymerization technology can be used as the spinning material that two-step approach solvent spinning technology is made high purifying polyacrylonitrile base carbon fiber precursors.Polyacrylonitrile resin ash after the washing can be reduced to below 0.1 ‰, and the content of alkalimetal ion is lower than 0.05 ‰.
Below will the invention will be further described by specific embodiment.
In an embodiment, metal element content adopts flame atomic absorption spectrometry, and the measuring method of ash is as described below:
Get sample (being accurate to 0.0001g) about 2g and place porcelain crucible, the crucible that sample is housed is placed on the electric furnace temperature heating 10～30min to be no more than 120 ℃, evaporate the water through 800 ℃ of temperature calcinations.Treat that filter paper is firing, crucible put into 800 ℃ high temperature resistance furnace after the dryness residue occurring, calcination 30min makes it ashing, after taking out from High Temperature Furnaces Heating Apparatus, moves in the moisture eliminator and is cooled to room temperature, weighs.And be calculated as follows:
In the formula: m
1Be ash content quality (g) after the style calcination, m is sample mass (g).
Embodiment
The spinning material polyacrylonitrile resin that embodiment adopts makes by aqueous suspension polymerization technology, and second, third comonomer except that vinyl cyanide is respectively methyl acrylate and methylene-succinic acid, and three's the weight ratio that feeds intake is 97: 2: 1.The polymeric initiator system is a redox system, and wherein oxygenant is a sodium chlorate, and reductive agent is a Sodium Pyrosulfite.
The ash that records the polyacrylonitrile resin raw material is that 1.62 ‰, Na ion contents are 0.25 ‰.
[embodiment 1～10]
Place deionized water to soak swelling above-mentioned spinning material polyacrylonitrile resin, water temperature is controlled at required temperature range, and unnecessary moisture content was sloughed in taking-up after immersion was swelling to the required time.Soak the swollen processing condition and see Table 1;
Place aqueous acid through soaking the swollen polyacrylonitrile resin, impose to stir and carry out pickling.Embodiment 1～8 adopts nitric acid, and embodiment 9～10 adopts hydrochloric acid, and other acid cleaning process condition sees Table 1;
Then that polyacrylonitrile resin is extremely neutral with rinsed with deionized water, rinsing temperature sees Table 1;
At last with the polyacrylonitrile resin vacuum filtering and dewatering, and under 80～100 ℃ of temperature, carry out drying, be lower than 3% until the water ratio of resin
Measure the ash and the Na ion content of polyacrylonitrile resin, the results are shown in Table 2.
Table 1.
* weight ratio=polyacrylonitrile resin: aqueous acid
Table 2.
| Ash (‰) | Na ion content (‰) | |
| Embodiment 1 | 0.099 | 0.050 |
| Embodiment 2 | 0.098 | 0.045 |
| Embodiment 3 | 0.098 | 0.041 |
| Embodiment 4 | 0.090 | 0.050 |
| Embodiment 5 | 0.089 | 0.042 |
| Embodiment 6 | 0.089 | 0.048 |
| Embodiment 7 | 0.080 | 0.032 |
| Embodiment 8 | 0.082 | 0.040 |
| Embodiment 9 | 0.099 | 0.043 |
| Ash (‰) | Na ion content (‰) | |
| Embodiment 10 | 0.099 | 0.041 |
Claims (7)
1. method of removing alkali metal impurity in the polyacrylonitrile resin, it may further comprise the steps successively:
1) polyacrylonitrile resin places deionized water to soak swelling 1～2.5 hour, and water temperature is controlled to be 20～50 ℃;
2) polyacrylonitrile resin is placed aqueous acid impose stirring and carry out pickling, nitric acid or hydrochloric acid are adopted in acid, and the pH value of aqueous acid is 0.1～3.0, and the weight ratio of polyacrylonitrile resin and aqueous acid is 1: (4～20), pickling temperature is 25～60 ℃, and the pickling time is 0.5～1.5 hour;
3) polyacrylonitrile resin is extremely neutral with rinsed with deionized water, rinsing temperature is 25～60 ℃;
4) polyacrylonitrile resin is dewatered and is dry.
2. the method for alkali metal impurity in the removal polyacrylonitrile resin according to claim 1 is characterized in that the described water temperature of step 1 is controlled to be 30～40 ℃.
3. the method for alkali metal impurity in the removal polyacrylonitrile resin according to claim 1, the pH value that it is characterized in that the described aqueous acid of step 2 is 0.3～1.6.
4. the method for alkali metal impurity in the removal polyacrylonitrile resin according to claim 1, the weight ratio that it is characterized in that described polyacrylonitrile resin of step 2 and salpeter solution is 1: (4～12).
5. the method for alkali metal impurity in the removal polyacrylonitrile resin according to claim 1 is characterized in that the described pickling temperature of step 2 is 35～45 ℃.
6. the method for alkali metal impurity in the removal polyacrylonitrile resin according to claim 1 is characterized in that the described rinsing temperature of step 3 is 40～50 ℃.
7. the method for alkali metal impurity in the removal polyacrylonitrile resin according to claim 1, it is characterized in that described polyacrylonitrile resin makes with aqueous suspension polymerization technology, the polymeric initiator is water miscible Oxidizing and Reducing Agents, wherein oxygenant is a kind of in ammonium persulphate, Potassium Persulphate, hydrogen peroxide or the sodium chlorate, or two or more mixtures; Reductive agent is a kind of in Sodium Pyrosulfite, sodium bisulfite or the S-WAT, or two or more mixtures.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2006101172439A CN101165072B (en) | 2006-10-18 | 2006-10-18 | Method for removing alkali metal impurity in polyacrylonitrile resin |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2006101172439A CN101165072B (en) | 2006-10-18 | 2006-10-18 | Method for removing alkali metal impurity in polyacrylonitrile resin |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101165072A CN101165072A (en) | 2008-04-23 |
| CN101165072B true CN101165072B (en) | 2010-09-15 |
Family
ID=39333941
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2006101172439A Active CN101165072B (en) | 2006-10-18 | 2006-10-18 | Method for removing alkali metal impurity in polyacrylonitrile resin |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101165072B (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102953153B (en) * | 2011-08-25 | 2016-01-20 | 中国石油化工股份有限公司 | A kind of preparation method of polyacrylonitrile-based carbon fibre |
| CN102953154B (en) * | 2011-08-25 | 2016-09-14 | 中国石油化工股份有限公司 | A kind of manufacture method of polyacrylonitrile-based carbon fibre |
| CN102953156A (en) * | 2011-08-25 | 2013-03-06 | 中国石油化工股份有限公司 | Manufacturing method for polyacrylonitrile-based carbon fiber |
| CN102953157B (en) * | 2011-08-25 | 2016-01-20 | 中国石油化工股份有限公司 | The preparation method of polyacrylonitrile-based carbon fibre |
| CN102953145B (en) * | 2011-08-25 | 2016-11-02 | 中国石油化工股份有限公司 | The method preparing polyacrylonitrile base carbon fiber precursors |
| CN102953139B (en) * | 2011-08-25 | 2016-01-20 | 中国石油化工股份有限公司 | The preparation method of polyacrylonitrile base carbon fiber precursors |
| CN102953152B (en) * | 2011-08-25 | 2017-04-12 | 中国石油化工股份有限公司 | Preparation method for polyacrylonitrile-based carbon fiber |
| CN102953143B (en) * | 2011-08-25 | 2016-06-29 | 中国石油化工股份有限公司 | A kind of preparation method of polyacrylonitrile base carbon fiber precursors |
| CN111073020A (en) * | 2019-12-31 | 2020-04-28 | 山东华夏神舟新材料有限公司 | Method for effectively controlling yellowing of polymer |
| CN112345478B (en) * | 2020-10-12 | 2022-09-27 | 威海市计量所 | Method for testing content of residual dimethyl sulfoxide in polyacrylonitrile protofilament |
| CN114225496B (en) * | 2021-12-07 | 2023-04-11 | 明士(北京)新材料开发有限公司 | Purification method and purification device for high-performance polymer resin |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1600640A (en) * | 1977-05-26 | 1981-10-21 | Hitco | Method of removing alkali and alkaline earth impurities from carbonizable polyacrylonitrile material |
| US4507272A (en) * | 1983-05-09 | 1985-03-26 | Hitco | Method of purifying partially carbonized pan material prior to carbonization |
| CN1079751A (en) * | 1991-11-22 | 1993-12-22 | 三菱丽阳株式会社 | The purification process of polyacrylonitrile |
-
2006
- 2006-10-18 CN CN2006101172439A patent/CN101165072B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1600640A (en) * | 1977-05-26 | 1981-10-21 | Hitco | Method of removing alkali and alkaline earth impurities from carbonizable polyacrylonitrile material |
| US4388289A (en) * | 1977-05-26 | 1983-06-14 | Hitco | Method of removing alkali and alkaline earth metal impurities from oxidized pan material |
| US4507272A (en) * | 1983-05-09 | 1985-03-26 | Hitco | Method of purifying partially carbonized pan material prior to carbonization |
| CN1079751A (en) * | 1991-11-22 | 1993-12-22 | 三菱丽阳株式会社 | The purification process of polyacrylonitrile |
Non-Patent Citations (2)
| Title |
|---|
| 郁铭芳.聚丙烯腈基碳纤维原丝的工艺研究.金山油化纤 04.2001,(04),1-4. |
| 郁铭芳.聚丙烯腈基碳纤维原丝的工艺研究.金山油化纤 04.2001,(04),1-4. * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN101165072A (en) | 2008-04-23 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101165072B (en) | Method for removing alkali metal impurity in polyacrylonitrile resin | |
| CN100557098C (en) | A kind of manufacture method of polyacrylonitrile base carbon fiber precursors | |
| CN100570026C (en) | The manufacture method of polyacrylonitrile base carbon fiber precursors | |
| CN102953153B (en) | A kind of preparation method of polyacrylonitrile-based carbon fibre | |
| US4001382A (en) | Process for producing carbon fibers having excellent physical properties | |
| JPS5848643B2 (en) | High purity acrylic carbon fiber | |
| CN101050564A (en) | Method for producing poly acrylonitrile fiber bundle PAN-base carbon fiber primary fiber | |
| CN102953151A (en) | Preparation method for polyacrylonitrile-based carbon fiber | |
| CN102953138B (en) | A kind of manufacture method of polyacrylonitrile base carbon fiber precursors | |
| CN102953141A (en) | Manufacturing method for polyacrylonitrile-based carbon fiber protofilament | |
| CN102953139B (en) | The preparation method of polyacrylonitrile base carbon fiber precursors | |
| EP0543418B1 (en) | Method of purifying polyacrylonitrile | |
| CN102953156A (en) | Manufacturing method for polyacrylonitrile-based carbon fiber | |
| CN102953158A (en) | Manufacturing method for polyacrylonitrile-based carbon fiber | |
| JP2015183166A (en) | Acrylonitrile-based copolymer, acrylonitrile-based carbon fiber precursor fiber and method for producing carbon fiber | |
| CN102953154B (en) | A kind of manufacture method of polyacrylonitrile-based carbon fibre | |
| CN102953144A (en) | Preparation method for polyacrylonitrile-based carbon fiber protofilament | |
| JP3048449B2 (en) | Acrylonitrile precursor fiber | |
| CN102953142B (en) | A kind of method manufacturing polyacrylonitrile base carbon fiber precursors | |
| CN114481349B (en) | Preparation method of high-strength alkali-resistant polyacrylonitrile fiber and polyacrylonitrile fiber | |
| CN102953157B (en) | The preparation method of polyacrylonitrile-based carbon fibre | |
| JP7420608B2 (en) | Method for producing carbon fiber precursor fiber | |
| CN102953145B (en) | The method preparing polyacrylonitrile base carbon fiber precursors | |
| CN102953152B (en) | Preparation method for polyacrylonitrile-based carbon fiber | |
| JPH0219513A (en) | Production of carbon fiber having high strength and high modulus of elasticity |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |