CN102242415A - Method for improving spinnability and after processing characteristic of polyimide fiber - Google Patents
Method for improving spinnability and after processing characteristic of polyimide fiber Download PDFInfo
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- CN102242415A CN102242415A CN 201110118359 CN201110118359A CN102242415A CN 102242415 A CN102242415 A CN 102242415A CN 201110118359 CN201110118359 CN 201110118359 CN 201110118359 A CN201110118359 A CN 201110118359A CN 102242415 A CN102242415 A CN 102242415A
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Abstract
The invention relates to a method for improving spinnability and an after processing characteristic of a polyimide fiber. The method comprises the following steps: (1) adding a dianhydride monomer and two diamines monomers into a solvent, and forming a terpolymerization polyamide acids solution at a temperature of -5-20 DEG C; (2) adopting dry method spinning formation to carry out deaeration on the above polyamide acids solution in vacuum, entering a spinning channel through a spinning assembly, and carrying out winding shaping on the channel to obtain a polyamide acids fiber; (3) subjecting the obtained polyamide acids fiber to a heat treatment and a heat stretching treatment. The method of the present invention has the characteristics of simple operation and low cost. The obtained polyimide fiber has good spinnability, good mechanical property, and soft handfeel of fiber. Maneuverability of the fiber in downstream product processing like braiding and nonwoven operations is improved. The polyimide fiber of the present invention can be widely applied to production of a composite material reinforcing fiber, a reinforcing core, a filtering material of high temperature substance, an insulating material and the like.
Description
Technical field
The invention belongs to the preparation field of specialty synthetic fibre, particularly a kind of method of improving polyimide fiber spinnability and back processing characteristics.
Background technology
Polyimide fiber has good heat endurance, good mechanical performance as a class of high-performance fiber, and lower water imbibition can be used in harsher environment.Polyimide fiber can be weaved into cable, is made into fabric or makes nonwoven fabric, is used in the aspect such as filtration, fire insulation felt, fire protection flame retarding clothes of high temperature, radioactivity or organic gas.
The existing polyimide fiber preparation method generally comprises one-step method forming technology, two-step method wet spinning process and two-step method dry method route.Wherein one-step method is to adopt polyimide solution directly to carry out spinning to prepare the polyamides subfiber, as Chinese invention patent ZL 02112048.X, U.S. Pat 4370290, US 5378420, the characteristics of this method are: the precursor of spinning need not to carry out imidizate again, and technological process is short, and the polyimide fiber mechanical property that is obtained is higher, but choice of Solvent is difficulty comparatively, often has higher toxicity.Two-step method is to adopt common non-proton intensive polar solvent, as N-Methyl pyrrolidone (NMP), dimethylacetylamide (DMAC), its method be earlier with diamines and dianhydride at low temperatures polycondensation generate polyamic acid stoste, carry out wet spinning or dry-wet spinning then, precursor obtains polyimide fiber through washing, drying, elevated temperature heat imidization (250～450 ℃).As day disclosure special permission communique JP3287815, JP4018115 all adopts two-step method; The characteristics of this technology are: solved the general molten insoluble processability difficult problem of bringing of polyimide fiber, but spinning coagulation bath has used a large amount of water, the spinning technique after coagulation bathe with a large amount of solvent together, unfavorable to energy-saving and emission-reduction.The dry spinning technology path is a preparation polyimide fiber other method, as national inventing patent 200610116652.7,201010146335.6, U.S. Pat P 3415782, USP 4640972 all discloses this method, at first polyamic acid solution enters the high temperature path by spinneret orifice, solvent at high temperature volatilizees, and forms polyamic acid fiber (precursor fibre), winding shaping; Afterwards, precursor fibre obtains polyimide fiber through heating, and last drawn operation obtains high-performance fiber.
Yet, because the characteristics of polyimide molecule structure, phenyl ring density is relatively large in molecular backbone, although this is favourable to mechanical property and the heat resistance that improves fiber, but this rigid chain molecule causes the rigidity of fiber stronger, and fragility increases, and colludes with intensity decreases, the post-production that is unfavorable for fiber is used, as braiding, non-weaving cloth etc.
Summary of the invention
Technical problem to be solved by this invention provides a kind of method of improving polyimide fiber spinnability and back processing characteristics, and this method is simple, and cost is low, and the polyimide fiber of gained is flexible to be increased, good hand touch, and the application prospect pipe is wide.
A kind of method of improving polyimide fiber spinnability and back processing characteristics of the present invention comprises:
(1) polyamic acid is synthetic: dianhydride monomer and two kinds of diamine monomers are joined in the solvent, the ternary polymerization polyamic acid solution that synthetic concentration is 10～30wt% under-5～20 ℃, wherein the mol ratio of two kinds of diamine monomers is 1: 9～9: 1, and the mol ratio of two kinds of diamine monomer sums and dianhydride monomer is 0.95: 1～1.10: 1;
(2) preparation of polyamic acid fiber: adopt dry spinning to be shaped,, enter spinning shaft by filament spinning component with the deaeration in a vacuum of above-mentioned polyamic acid solution, the temperature in path is 150～260 ℃, 8～15 meters of length, winding shaping under the path gets the polyamic acid fiber;
(3) imidizate of polyamic acid fiber and hot-stretch: the polyamic acid fiber of above-mentioned gained is heat-treated, and then carry out hot-stretch, get final product; Wherein heat treatment temperature is divided into two-stage, is respectively 170～280 ℃, 330～370 ℃; The hot-stretch temperature is at 300～520 ℃, and draw ratio is 2～8 times.
Dianhydride monomer described in the step (1) is a pyromellitic acid dianhydride, 3,3 ', 4, and 4 '-benzophenone tetracarboxylic acid dianhydride and 3,3 ', 4, a kind of in 4 '-bibenzene tetracarboxylic dianhydride.
First kind of diamine monomer described in the step (1) is 4,4 '-diaminodiphenyl ether, 1,4-phenylenediamine and 4, a kind of in 4 '-diaminodiphenylmethane; Second kind of diamine monomer is m-phenylene diamine (MPD), 3,3 '-diaminodiphenyl ether, 3,4 '-diaminobenzophenone and 2, a kind of in two [4-(4-amino-benzene oxygen) phenyl] propane of 2-.
Solvent described in the step (1) is N, and N '-dimethylacetylamide, N are a kind of in N '-dimethyl formamide, dimethyl sulfoxide solvent and the N-Methyl pyrrolidone.
The epimere of the path temperature described in the step (2) is 150～190 ℃, and the stage casing is 200～220 ℃, and hypomere is 210～260 ℃.
When polyamic acid solution enters the path in the step (2), can reclaim solvent by condensation.
In the step (3) during heat treatment, can adopt one or more the combination in heat pipe, hot plate, the high temperature oven.
Pyromellitic acid dianhydride, 3,3 ', 4,4 '-benzophenone tetracarboxylic acid dianhydride and 3,3 ', 4, the chemical structural formula of 4 '-bibenzene tetracarboxylic dianhydride is respectively:
4,4 '-diaminodiphenyl ether, 1,4-phenylenediamine and 4, the chemical structural formula of 4 '-diaminodiphenylmethane is respectively:
M-phenylene diamine (MPD), 3,3 '-diaminodiphenyl ether, 3,4 '-diaminobenzophenone and 2, the chemical structural formula of two [4-(4-amino-benzene oxygen) phenyl] propane of 2-is respectively:
Beneficial effect:
(1) the present invention makes the cost of fiber descend owing to selected the relatively low flexible chain diamines of cost for use, and to the polymer solution of same molecular weight, its apparent viscosity descends, and has improved the spinnability of polymer solution.
(2) fiber of the present invention's acquisition is flexible increases, and good hand touch has been improved such as the operability of post-production such as weaving, non-woven and the performance of product.
(3) polyimide fiber of the present invention can be widely used in the composite fortifying fibre, the enhancing core of cable, and the filtering material of high temperature material, insulating materials etc., the application prospect pipe is wide.
The specific embodiment
Below in conjunction with specific embodiment, further set forth the present invention.Should be understood that these embodiment only to be used to the present invention is described and be not used in and limit the scope of the invention.Should be understood that in addition those skilled in the art can make various changes or modifications the present invention after the content of having read the present invention's instruction, these equivalent form of values fall within the application's appended claims institute restricted portion equally.
Embodiment 1
(1) with 440 grams 4,4 '-diaminodiphenyl ether and 150 grams 3,3 '-diaminodiphenyl ether adds in the 4000ml dimethylacetylamide, is stirred to dissolving fully under 15 ℃; Afterwards, the 650g pyromellitic acid dianhydride is joined in this solution in batches, stirred 8 hours under nitrogen protection, obtain the polyamic acid spinning solution of faint yellow thickness, its inherent viscosity is 2.16dL/g;
(2) after the polyamic acid spinning solution deaeration with above preparation, on air spinning machine, carry out dry spinning, 10 meters of path length, the epimere of path temperature is 170 ℃, 200 ℃ in stage casing, 220 ℃ of hypomeres, winding shaping obtains the polyamic acid fiber afterwards; Wherein used spinneret orifice number is 30～100 holes, aperture 0.1mm;
(3) the polyamic acid fiber makes polyimide fiber through hot-imide, and the bi-level treatment temperature is respectively 270 ℃ and 370 ℃; Stretch 5 times down at 430 ℃, promptly obtain the high-performance polyimide fiber.
Embodiment 2
(1) with 330 grams 4,4 '-diaminodiphenyl ether and 350 grams 3,4 '-diaminobenzophenone adds in the 12000ml dimethyl formamide, is stirred to dissolving fully under 20 ℃; Afterwards, 720 gram pyromellitic acid dianhydrides are joined in this solution in batches, stirred 10 hours under the room temperature, obtain the polyamic acid spinning solution of faint yellow thickness, its inherent viscosity is 1.89dL/g;
(2) after the polyamic acid spinning solution deaeration with above preparation, on air spinning machine, carry out dry spinning, 15 meters of path length, the epimere of path temperature is 150 ℃, 200 ℃ in stage casing, 210 ℃ of hypomeres, winding shaping obtains the polyamic acid fiber afterwards;
(3) the polyamic acid fiber makes polyimide fiber through hot-imide, and the bi-level treatment temperature is respectively 170 ℃ and 330 ℃; Stretch 3 times down at 350 ℃, promptly obtain the high-performance polyimide fiber.
Embodiment 3
(1) 350 gram p-phenylenediamine (PPD) is added in the 12000ml solvent dimethylformamide, afterwards, with 2080 grams 3,3 ', 4,4 '-benzophenone tetracarboxylic dianhydride adds in this solution, stirred 6 hours down at-5 ℃, again 600 grams, 3,3 '-diaminodiphenyl ether is added in this solution, stirred again 4 hours, and obtained the polyamic acid spinning solution of faint yellow thickness;
(2) after the polyamic acid spinning solution deaeration with above preparation, on air spinning machine, carry out dry spinning, 10 meters of path length, the epimere of path temperature is 170 ℃, 210 ℃ in stage casing, 230 ℃ of hypomeres, winding shaping obtains the polyamic acid fiber afterwards;
(3) the polyamic acid fiber makes polyimide fiber through hot-imide, and the bi-level treatment temperature is respectively 170 ℃ and 330 ℃; Stretch 3 times down at 450 ℃, promptly obtain the high-performance polyimide fiber.
Embodiment 4
(1) with 150 grams 4,4 '-diaminodiphenylmethane and 300 grams 2, two [4-(4-amino-benzene oxygen) phenyl] propane of 2-add in the 5000ml dimethyl formamide, are stirred to dissolving fully under 5 ℃.Afterwards, with 450 grams 3,3 ', 4,4 '-benzophenone tetracarboxylic dianhydride (BTDA) joins in this solution in batches, stirs 10 hours under the room temperature, obtains the polyamic acid spinning solution of faint yellow thickness, and its inherent viscosity is 0.93dL/g;
(2) after the polyamic acid spinning solution deaeration with above preparation, on air spinning machine, carry out dry spinning, 10 meters of path length, the epimere of path temperature is 190 ℃, 220 ℃ in stage casing, 240 ℃ of hypomeres, winding shaping obtains the polyamic acid fiber afterwards, wherein used spinneret orifice number is 30～100 holes, aperture 0.1mm;
(3) the polyamic acid fiber makes polyimide fiber through hot-imide, and the bi-level treatment temperature is respectively 270 ℃ and 370 ℃; Stretch 7 times down at 500 ℃, promptly obtain the high-performance polyimide fiber.
Embodiment 5
(1) the 600g pyromellitic acid dianhydride is added in the 4000ml dimethyl sulfoxide solvent, be stirred to dissolving fully, add 280 grams 4 again, 4 '-diaminodiphenylmethane and 150 gram m-phenylene diamine (MPD)s, in-5 ℃ of following nitrogen atmospheres, stirred 8 hours, obtain the polyamic acid spinning solution of faint yellow thickness;
(2) after the polyamic acid spinning solution deaeration with above preparation, on air spinning machine, carry out dry spinning, 8 meters of path length, the epimere of path temperature is 150 ℃, 200 ℃ in stage casing, 210 ℃ of hypomeres, winding shaping obtains the polyamic acid fiber afterwards;
(3) the polyamic acid fiber makes polyimide fiber through hot-imide, and the bi-level treatment temperature is respectively 170 ℃ and 330 ℃; Stretch 5 times down at 300 ℃, promptly obtain the high-performance polyimide fiber.
Claims (7)
- One kind improve the polyimide fiber spinnability and the back processing characteristics method, comprising:(1) dianhydride monomer and two kinds of diamine monomers are joined in the solvent, the ternary polymerization polyamic acid solution that synthetic concentration is 10～30wt% under-5～20 ℃, wherein the mol ratio of two kinds of diamine monomers is 1: 9～9: 1, and the mol ratio of two kinds of diamine monomer sums and dianhydride monomer is 0.95: 1～1.10: 1;(2) adopt dry spinning to be shaped, with the deaeration in a vacuum of above-mentioned polyamic acid solution, enter spinning shaft by filament spinning component, the temperature in path is 150～260 ℃, 8～15 meters of length, and winding shaping under the path gets the polyamic acid fiber;(3) the polyamic acid fiber of above-mentioned gained is heat-treated, and then carry out hot-stretch, get final product; Wherein heat treatment temperature is divided into two-stage, is respectively 170～280 ℃, 330～370 ℃; The hot-stretch temperature is at 300～520 ℃, and draw ratio is 2～8 times.
- 2. a kind of method of improving polyimide fiber spinnability and back processing characteristics according to claim 1, it is characterized in that: the dianhydride monomer described in the step (1) is a pyromellitic acid dianhydride, 3,3 ', 4,4 '-benzophenone tetracarboxylic acid dianhydride and 3,3 ', 4, a kind of in 4 '-bibenzene tetracarboxylic dianhydride.
- 3. a kind of method of improving polyimide fiber spinnability and back processing characteristics according to claim 1, it is characterized in that: first kind of diamine monomer described in the step (1) is 4,4 '-diaminodiphenyl ether, 1,4-phenylenediamine and 4, a kind of in 4 '-diaminodiphenylmethane; Second kind of diamine monomer is m-phenylene diamine (MPD), 3,3 '-diaminodiphenyl ether, 3,4 '-diaminobenzophenone and 2, a kind of in two [4-(4-amino-benzene oxygen) phenyl] propane of 2-.
- 4. a kind of method of improving polyimide fiber spinnability and back processing characteristics according to claim 1, it is characterized in that: the solvent described in the step (1) is N, N '-dimethylacetylamide, N, a kind of in N '-dimethyl formamide, dimethyl sulfoxide solvent and the N-Methyl pyrrolidone.
- 5. a kind of method of improving polyimide fiber spinnability and back processing characteristics according to claim 1, it is characterized in that: the epimere of the path temperature described in the step (2) is 150～190 ℃, and the stage casing is 200～220 ℃, and hypomere is 210～260 ℃.
- 6. a kind of method of improving polyimide fiber spinnability and back processing characteristics according to claim 1 is characterized in that: when polyamic acid solution enters the path in the step (2), can reclaim solvent by condensation.
- 7. a kind of method of improving polyimide fiber spinnability and back processing characteristics according to claim 1 is characterized in that: in the step (3) during heat treatment, can adopt one or more the combination in heat pipe, hot plate, the high temperature oven.
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Cited By (7)
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| CN102660796A (en) * | 2012-04-27 | 2012-09-12 | 东华大学 | Polyimide fiber spinning solution based on 2,2-bi(3-amimo-4-hydroxycyclohexyl phenyl) hexafluoropropane and preparation method thereof |
| CN102978734A (en) * | 2012-11-19 | 2013-03-20 | 东华大学 | Preparation method of fine denier/superfine denier polyimide fibers |
| CN104499085A (en) * | 2014-11-19 | 2015-04-08 | 南通大学 | Method for improving strength, modulus, thermal stability and water resistance of polyimide fiber |
| CN105648567A (en) * | 2016-01-25 | 2016-06-08 | 江苏先诺新材料科技有限公司 | Polyimide superfine fiber and preparation method thereof |
| CN109295525A (en) * | 2018-09-21 | 2019-02-01 | 浙江浩睿新材料科技有限公司 | A kind of preparation method of polyimide fiber long filament |
| CN109735917A (en) * | 2018-12-19 | 2019-05-10 | 长沙新材料产业研究院有限公司 | A kind of ternary copolymerization polyimide spinning solution and preparation method |
| CN111764004A (en) * | 2020-06-24 | 2020-10-13 | 东华大学 | Preparation method of high-strength high-model polyimide profiled fiber |
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Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102660796A (en) * | 2012-04-27 | 2012-09-12 | 东华大学 | Polyimide fiber spinning solution based on 2,2-bi(3-amimo-4-hydroxycyclohexyl phenyl) hexafluoropropane and preparation method thereof |
| CN102660796B (en) * | 2012-04-27 | 2014-05-28 | 东华大学 | Polyimide fiber spinning solution based on 2,2-bi(3-amimo-4-hydroxycyclohexyl phenyl) hexafluoropropane and preparation method thereof |
| CN102978734A (en) * | 2012-11-19 | 2013-03-20 | 东华大学 | Preparation method of fine denier/superfine denier polyimide fibers |
| CN106400159A (en) * | 2014-11-19 | 2017-02-15 | 南通大学 | Method with simple process for improving polyimide fiber performance |
| CN104499085B (en) * | 2014-11-19 | 2016-11-30 | 南通大学 | Improve polyimide fiber intensity, modulus, heat stability and the method for water-resistance |
| CN104499085A (en) * | 2014-11-19 | 2015-04-08 | 南通大学 | Method for improving strength, modulus, thermal stability and water resistance of polyimide fiber |
| CN106400159B (en) * | 2014-11-19 | 2018-05-22 | 南通大学 | The method of raising polyimide fiber performance simple for process |
| CN105648567A (en) * | 2016-01-25 | 2016-06-08 | 江苏先诺新材料科技有限公司 | Polyimide superfine fiber and preparation method thereof |
| CN109295525A (en) * | 2018-09-21 | 2019-02-01 | 浙江浩睿新材料科技有限公司 | A kind of preparation method of polyimide fiber long filament |
| CN109295525B (en) * | 2018-09-21 | 2020-11-20 | 义乌华鼎锦纶股份有限公司 | Preparation method of polyimide fiber filament |
| CN109735917A (en) * | 2018-12-19 | 2019-05-10 | 长沙新材料产业研究院有限公司 | A kind of ternary copolymerization polyimide spinning solution and preparation method |
| CN111764004A (en) * | 2020-06-24 | 2020-10-13 | 东华大学 | Preparation method of high-strength high-model polyimide profiled fiber |
| CN111764004B (en) * | 2020-06-24 | 2021-06-29 | 东华大学 | Preparation method of high-strength high-model polyimide profiled fiber |
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