CN102079797B - Demonomerization and defoamation method of acrylonitrile polymerization solution - Google Patents
Demonomerization and defoamation method of acrylonitrile polymerization solution Download PDFInfo
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- CN102079797B CN102079797B CN2010106032296A CN201010603229A CN102079797B CN 102079797 B CN102079797 B CN 102079797B CN 2010106032296 A CN2010106032296 A CN 2010106032296A CN 201010603229 A CN201010603229 A CN 201010603229A CN 102079797 B CN102079797 B CN 102079797B
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Abstract
The invention relates to a demonomerization and defoamation method of acrylonitrile polymerization solution. The method is as follows: continuously removing residual acrylonitrile monomer in the acrylonitrile polymerization solution by a supergravity device with a rotator and a packing layer and a screw extruder; and then completing the demonomerization and defoamation process through a defoamation device. By using the method in the invention, the demonomerization period can be greatly shortened, thereby being beneficial to obtaining high-quality spinning solution; and continuous operation can be achieved, and simultaneously, the subsequent defoamation load of the spinning solution can be alleviated.
Description
Technical field
The invention belongs to the field of acrylonitrile base carbon fiber precursor preparation, be specifically related to the single defoaming method of taking off of a kind of acrylonitrile polymerization solution.
Background technology
In the production process of PAN base carbon fiber protofilament, especially for the DMSO one-step method production process, seldom accomplish polymerisation conversion 100% usually, because in the polymerization later stage, transformation efficiency rises extremely slow, pursues too high transformation efficiency and can cause production efficiency to descend.In addition, in polymerization latter stage, because monomer concentration is very low in the polymerization system; The polymericular weight that forms is very low; Along with the prolongation of polymerization time, the molecular weight distribution that obtains can broaden gradually, and the polymer fluid of the wide distribution of molecular weight is unfavorable for obtaining high-performance carbon fibre usually.
Therefore, producer controls transformation efficiency mostly about 90% at present.In this case, single technology of taking off in later stage just seems particularly crucial, because acrylonitrile monemer still has small portion of residual after the polymerization, takes off single deaeration effect and directly determines spinning quality.If residual monomer is too many in the polymer fluid, these monomers will continue polymerization in the deaeration process, cause the spinning solution solid content inconsistent, will cause precursor CV value to increase.For wet-spinning,, can cause that the lousiness amount increases in the spinning process if deaeration is not thorough; For dry-wet spinning technology, contain bubble in the spinning solution and will cause material in spinning jet surface cross flow, to the consequence of bringing on a disaster property of spinning process.
Traditional production process adopts scraper-type or umbrella page structure usually, adopt the scraper-type structure to take off single device volume big, evaporation surface is little, and is difficult in maintenance; And when adopting umbrella page structure because there is threshold value in the bed thickness on the umbrella page or leaf, surpass threshold value after, be prone to and take off single deaeration effect and descend, therefore this method efficient is not high.
Rotation hypergravity bed is one type of new and effective mass-and heat-transfer device; The rotor that has high speed rotating like described hypergravity devices of patent such as CN01143459.7, CN 91229204.0 and CN92100093.6; Fixing various fillers in the rotor; Material in filler because filler has very high specific surface area usually, can promote the carrying out of mass-and heat-transfer process in the following minute timing of centrifugal action greatly.
Patent CN101856570A discloses a kind of carbon fiber spinning solution and has dynamically taken off single defoaming device, and this device has adopted the hypergravity device to take off list, in the deaeration process, has adopted the auxiliary method of UW.It is to occur in scraper-type to take off only unit that this device takes off single process, adopts scraper plate that polymers soln is spread to millimetre-sized liquid film, uses this device to take off residual monomer content≤0.1% in the product after single deaeration, bubbles number≤5, solvent loss amount≤5%.But this device prepares more complicated, and taking off in single deaeration product of obtaining of this method, though residual monomer content can reach a little less than 0.1%, in fact adopts this area umbrella page commonly used to take off single structure, also can reach and similarly take off the single-action fruit.
In sum, the single defoaming method that takes off that does not also have a kind of solution of acrylonitrile polymerization preferably at present.
Summary of the invention
The objective of the invention is to overcome the deficiency of prior art, provide taking off of a kind of acrylonitrile polymerization solution single defoaming method.This method can efficiently remove remaining acrylonitrile monemer in the acrylonitrile polymerization solution, and can remove the bubble in the material simultaneously.
Above-mentioned purpose of the present invention is achieved through following technical scheme:
A kind of acrylonitrile polymerization solution take off single defoaming method continuously, comprise the steps:
(1) the nearly turning axle place of acrylonitrile polymerization solution from the hypergravity device joined in the rotor of hypergravity device; Be fixed with filler in the said rotor; Start hypergravity device and vacuum system simultaneously; Acrylonitrile polymerization solution obtains nano level material at filling surface after shearing under the hypergravity effect that the rotor high-speed rotation produces, material compiles in the bottom of hypergravity device after being thrown away by rotor edge under the action of the centrifugal;
(2) material after step (1) is handled flows into the screw extrusion press that links to each other with the bottom of hypergravity device, is delivered to defoaming device through screw extrusion press;
(3) polymers soln is through finally obtaining taking off the product of single deaeration after the defoaming device deaeration.
Said acrylonitrile polymerization solution is produced the polymeric solution in polyacrylonitrile base carbon fiber precursors or the acrylic fiber process for the DMSO 99.8MIN. single stage method.
Said acrylonitrile polymerization solution is vinyl cyanide and the copolymerization product of comonomer in DMSO 99.8MIN..
Said comonomer is preferably any one or a few in vinylformic acid, methylacrylic acid, methyl acrylate, TEB 3K, ethyl propenoate, n-butyl acrylate, NSC 20949, Hydroxyethyl acrylate, Propylene glycol monoacrylate, vinylformic acid hydroxy butyl ester, acrylic amide, toxilic acid, maleic anhydride, methylene-succinic acid, monomethyl itaconate, the methylene-succinic acid mono ethyl ester.
The content of said comonomer is preferably and accounts for 0%～20% of total polymerization monomer mass.
The unreacted acrylonitrile monomer mass accounts for 0.01%～10% of gross product quality in the said acrylonitrile polymerization solution.
The unreacted acrylonitrile monomer mass is preferably and accounts for 0.01%～5% of gross product quality in the said acrylonitrile polymerization solution.
Said polymeric solution temperature is preferably 30～90 ℃, and the hypergravity temperature in the kettle is preferably 30～90 ℃, and absolute pressure is preferably 10Pa～50kPa in the hypergravity still.
More preferably 40～70 ℃ of said polymeric solution temperature, absolute pressure is 50Pa～10kPa in 40～70 ℃ of the hypergravity temperature in the kettle, hypergravity still.
Single process of taking off in the hypergravity device of the present invention occurs in the packing layer in the rotor; The hypergravity effect that utilizes high speed rotating to produce constantly cuts into nano level film, silk or drop with polymers soln at filling surface; But produce the huge phase interface of fast updating, take off single effect thereby improved greatly.
Material of the present invention moves towards as follows: material joins in the rotor from the nearly turning axle of hypergravity device place; Distribution through filler in the rotor; The residual monomer volatilization is drained through vacuum-lines under negative pressure, and material is then thrown away by rotor edge under the action of the centrifugal, is collected under the action of gravity by the still wall and comes together in bottom of device; The bottom material flows into the screw extrusion press of lower end under self-gravity action, be transported to defoaming device at last.
Screw extrusion press is in the method as a kind of material conveying mechanism with sealing function.Adopt screw extrusion press can realize hypergravity is taken off the independent control of single device and umbrella leaf formula defoaming device vacuum pressure.In taking off the process of single deaeration, not necessarily identical in the hypergravity device with the required vacuum tightness of defoaming device, the single defoaming method control of taking off of different material is had greater flexibility and flexibility after adopting screw extrusion press.Simultaneously, the coupling of screw rod machine can realize taking off continuously single deaeration.
Because negative pressure simultaneously can cause the bubble in the material to break, take off through hypergravity therefore that number of bubbles significantly reduces in the material behind single device, can alleviate the load of conventional defoaming device greatly, improve deaeration efficient.
Process the inventive method is taken off the acrylonitrile polymer solution after single deaeration, and the content of remaining comonomer is lower than 0.01 weight %, and does not have bubble in the feed liquid.
Compared with prior art, the present invention has following beneficial effect:
Square law device of the present invention is easy; The packing layer of the present invention in the rotor of hypergravity device takes off single process; The hypergravity effect that utilizes high speed rotating to produce constantly cuts into nano level film, silk or drop with polymers soln at filling surface; But produce the huge phase interface of fast updating, take off single effect thereby improved greatly;
After present method was taken off list, the residual monomer content in the polymeric solution was lower than 0.01%, has improved an one magnitude than prior art, and the polymeric solution after the deaeration does not have bubble, obviously is superior to prior art yet; The present invention has adopted hypergravity device, screw extrusion press, deaeration still to unite to take off single deaeration, can realize taking off continuously single deaeration, and independent control takes off list and deaeration vacuum tightness, and the effect of present method obviously is superior to the single deaeration effect of taking off of prior art;
Because that under the effect of hypergravity device and screw extrusion press, has improved product greatly takes off single-action really; The deaeration technology in later stage is carried out more easily, and still be that the less small molecules liquid of viscosity is removed the bubble in the material equally fully no matter for the bigger macromolecular solution of viscosity.
Description of drawings
Fig. 1 is the schema that takes off single defoaming method according to the invention;
Wherein, 1 is polymeric kettle; 2 is toothed gear pump; 3 take off single still for hypergravity; 4 is screw extrusion press; 5 is vacuum pump; 6 is umbrella formula deaeration still.
Embodiment
Come further to explain the present invention below in conjunction with embodiment, but embodiment does not do any type of qualification to the present invention.Following monomer content all is weight percentage.
Embodiment 1
Material 60kg in the polymeric kettle, temperature is controlled to be 65 ℃.Open hypergravity and take off single still wall chuck recirculated water, 65 ℃ of water temperatures.Single still vacuum pump is taken off in unlatching, and keeping absolute pressure is 1000Pa.Start rotor electric machine, rotating speed is 1400 commentaries on classics.Start volume pump, with the flow of 15kg/h product pump is gone into hypergravity and take off single still, start screw extrusion press behind the 2h, flow set is 15kg/h, and material is squeezed into the deaeration still.Stop volume pump behind the 4h, stop screw extrusion press behind the 6h, take off single deaeration end of processing.
Vapor-phase chromatography detects takes off residual monomer content in the polymkeric substance of single front and back, and testing conditions is: external standard method, and 230 ℃ of fid detector temperature, the DB-624 chromatographic column, 190 ℃ of column temperatures, 210 ℃ of injection ports, splitting ratio 1/10, tail blows 30ml/min.Headspace sampling: 60 ℃ of furnace temperature, balance 45min, sample size 1000 μ l.Detected result: take off single preceding acrylonitrile content 0.8%, take off single back content 0.009%.Take off after single deaeration and do not have bubble in the feed liquid.
Embodiment 2
Material 60kg in the polymeric kettle, temperature is controlled to be 40 ℃.Open hypergravity and take off single still wall chuck recirculated water, 40 ℃ of water temperatures.Single still vacuum pump is taken off in unlatching, and keeping absolute pressure is 400Pa.Start rotor electric machine, rotating speed is 1400 commentaries on classics.Start volume pump, with the flow of 15kg/h product pump is gone into hypergravity and take off single still, start screw extrusion press behind the 2h, flow set is 15kg/h, and material is squeezed into the deaeration still.Stop volume pump behind the 4h, stop screw extrusion press behind the 6h, take off single deaeration end of processing.
Vapor-phase chromatography detects takes off residual monomer content in the polymkeric substance of single front and back, and testing conditions is: external standard method, and 230 ℃ of fid detector temperature, the DB-624 chromatographic column, 190 ℃ of column temperatures, 210 ℃ of injection ports, splitting ratio 1/10, tail blows 30ml/min.Headspace sampling: 60 ℃ of furnace temperature, balance 45min, sample size 1000 μ l.Detected result: take off single preceding acrylonitrile content 0.3%, take off single back content 0.008%.Take off after single deaeration and do not have bubble in the feed liquid.
Embodiment 3
Material 60kg in the polymeric kettle, temperature is controlled to be 55 ℃.Open hypergravity and take off single still wall chuck recirculated water, 55 ℃ of water temperatures.Single still vacuum pump is taken off in unlatching, and keeping absolute pressure is 2kPa.Start rotor electric machine, rotating speed is 1400 commentaries on classics.Start volume pump, with the flow of 10kg/h product pump is gone into hypergravity and take off single still, start screw extrusion press behind the 3h, flow set is 10kg/h, and material is squeezed into the deaeration still.Stop volume pump behind the 6h, stop screw extrusion press behind the 9h, take off single deaeration end of processing.
Vapor-phase chromatography detects takes off residual monomer content in the polymkeric substance of single front and back, and testing conditions is: external standard method, and 230 ℃ of fid detector temperature, the DB-624 chromatographic column, 190 ℃ of column temperatures, 210 ℃ of injection ports, splitting ratio 1/10, tail blows 30ml/min.Headspace sampling: 60 ℃ of furnace temperature, balance 45min, sample size 1000 μ l.Detected result: take off single preceding acrylonitrile content 5.3%, take off single back content 0.026%.Take off after single deaeration and do not have bubble in the feed liquid.
Embodiment 4
Material 60kg in the polymeric kettle, temperature is controlled to be 70 ℃.Open hypergravity and take off single still wall chuck recirculated water, 60 ℃ of water temperatures.Single still vacuum pump is taken off in unlatching, and keeping absolute pressure is 10kPa.Start rotor electric machine, rotating speed is 2000 commentaries on classics.Start volume pump, with the flow of 10kg/h product pump is gone into hypergravity and take off single still, start screw extrusion press behind the 3h; Screw rod machine outlet T-valve is switched to polymeric kettle one side; Flow set is 10kg/h, behind the 6h T-valve is switched to deaeration still side, stops volume pump behind the 9h; Stop screw extrusion press behind the 12h, take off single deaeration end of processing.
Vapor-phase chromatography detects takes off residual monomer content in the polymkeric substance of single front and back, and testing conditions is: external standard method, and 230 ℃ of fid detector temperature, the DB-624 chromatographic column, 190 ℃ of column temperatures, 210 ℃ of injection ports, splitting ratio 1/10, tail blows 30ml/min.Headspace sampling: 60 ℃ of furnace temperature, balance 45min, sample size 1000 μ l.Detected result: take off single preceding acrylonitrile content 8.3%, take off single back content 0.009%.Take off after single deaeration and do not have bubble in the feed liquid.
Comparative Examples 1
Temperature of charge is controlled to be 65 ℃ in the polymeric kettle.Open umbrella shape and take off single deaeration still chuck recirculated water, 65 ℃ of water temperatures.Open umbrella shape and take off single deaeration still vacuum pump, the adjustment absolute pressure is 1000Pa.Start volume pump, with the flow of 1.2kg/h material is pumped into umbrella shape and take off single deaeration still, dnockout finishes behind the 50h, takes off single deaeration end of processing.The vapor-phase chromatography detected result is: take off single preceding acrylonitrile content 0.8%, take off single back content 0.072%.Take off after single deaeration and do not have bubble in the feed liquid.
Comparative Examples 2
Temperature of charge is controlled to be 65 ℃ in the polymeric kettle.Open umbrella shape and take off single deaeration still chuck recirculated water, 65 ℃ of water temperatures.Open umbrella shape and take off single deaeration still vacuum pump, the adjustment absolute pressure is 1000Pa.Start volume pump, with the flow of 1.5kg/h material is pumped into umbrella shape and take off single deaeration still, dnockout finishes behind the 40h, takes off single deaeration end of processing.The vapor-phase chromatography detected result is: take off single before acrylonitrile content 0.8%, take off single back content 0.105%, taking off after single deaeration has bubble in the feed liquid, can't carry out spinning.
Claims (6)
- An acrylonitrile polymerization solution take off single defoaming method continuously, it is characterized in that comprising the steps:(1) the nearly turning axle place of acrylonitrile polymerization solution from the hypergravity device joined in the rotor of hypergravity device; Be fixed with filler in the said rotor; Start hypergravity device and vacuum system simultaneously; Acrylonitrile polymerization solution obtains nano level material at filling surface after shearing under the hypergravity effect that the rotor high-speed rotation produces, material compiles in the bottom of hypergravity device after being thrown away by rotor edge under the action of the centrifugal;(2) material after step (1) is handled flows into the screw extrusion press that links to each other with the bottom of hypergravity device, is delivered to defoaming device through screw extrusion press;(3) polymers soln is through finally obtaining taking off the product of single deaeration after the defoaming device deaeration;Said acrylonitrile polymerization solution is acrylonitrile homopolymer or vinyl cyanide and the multipolymer of comonomer in DMSO 99.8MIN.;Said comonomer is any one or more than one the mixture in vinylformic acid, methylacrylic acid, methyl acrylate, TEB 3K, ethyl propenoate, n-butyl acrylate, NSC 20949, Hydroxyethyl acrylate, Propylene glycol monoacrylate, vinylformic acid hydroxy butyl ester, acrylic amide, toxilic acid, maleic anhydride, methylene-succinic acid, monomethyl itaconate, the methylene-succinic acid mono ethyl ester;Said polymeric solution temperature is 30～90 ℃, and absolute pressure is 10Pa～50kPa in 30～90 ℃ of the hypergravity temperature in the kettle, hypergravity still.
- 2. acrylonitrile polymerization solution as claimed in claim 1 take off single defoaming method continuously, it is characterized in that said acrylonitrile polymerization solution is that the DMSO 99.8MIN. single stage method is produced the polymeric solution in polyacrylonitrile base carbon fiber precursors or the acrylic fiber process.
- 3. acrylonitrile polymerization solution as claimed in claim 1 take off single defoaming method continuously, it is characterized in that the content of said comonomer is not higher than 20% in the total polymerization monomer mass.
- 4. acrylonitrile polymerization solution as claimed in claim 1 take off single defoaming method continuously, it is characterized in that the unreacted acrylonitrile monomer mass accounts for 0.01%～10% of gross product quality in the said acrylonitrile polymerization solution.
- 5. acrylonitrile polymerization solution as claimed in claim 4 take off single defoaming method continuously, it is characterized in that the unreacted acrylonitrile monomer mass accounts for 0.01%～5% of gross product quality in the said acrylonitrile polymerization solution.
- 6. acrylonitrile polymerization solution as claimed in claim 1 take off single defoaming method continuously, it is characterized in that said polymeric solution temperature is 40～70 ℃, absolute pressure is 50Pa～10kPa in 40～70 ℃ of the hypergravity temperature in the kettle, hypergravity still.
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| CN103422179B (en) * | 2012-05-16 | 2016-04-13 | 中国石油化工股份有限公司 | The defoaming method of carbon fiber spinning primary fluid |
| CN103469316B (en) * | 2013-09-11 | 2016-02-24 | 中石化上海工程有限公司 | Produce the defoaming method of polyacrylonitrile-radical PAN carbon fiber stoste |
| CN105037619B (en) * | 2015-08-12 | 2018-04-20 | 广州金发碳纤维新材料发展有限公司 | A kind of de- folk prescription method of polyacryl-nitrile spinning fluid |
| CN106589177B (en) * | 2015-10-19 | 2018-09-14 | 中国石油化工股份有限公司 | The residual list of acrylonitrile polymerization solution removal and the method and its device for adjusting solvent content |
| CN107308674B (en) * | 2017-08-17 | 2023-06-16 | 武汉智宏思博环保科技有限公司 | Organic solvent dewatering equipment with super-gravity bed combined with molecular sieve membrane |
| CN109321994B (en) * | 2018-09-30 | 2021-03-19 | 中国科学院山西煤炭化学研究所 | Polyacrylonitrile-based carbon fiber dry-wet spinning solution and preparation method thereof |
| CN109988258A (en) * | 2019-04-18 | 2019-07-09 | 中国科学院山西煤炭化学研究所 | A kind of de- single system of polymer fluid |
| CN110982076A (en) * | 2019-12-26 | 2020-04-10 | 江苏美思德化学股份有限公司 | Method for preparing low-volatile polysiloxane by using supergravity device |
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