CN101838861B - Method for preparing cellulose fiber - Google Patents
Method for preparing cellulose fiber Download PDFInfo
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- CN101838861B CN101838861B CN2010101647735A CN201010164773A CN101838861B CN 101838861 B CN101838861 B CN 101838861B CN 2010101647735 A CN2010101647735 A CN 2010101647735A CN 201010164773 A CN201010164773 A CN 201010164773A CN 101838861 B CN101838861 B CN 101838861B
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- cellulose
- ionic liquid
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- spinning
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Abstract
The invention discloses a method for preparing cellulose fiber. By using melting spinning technology, the method comprises the following steps of: 1, mixing cellulose and ionic liquid in a mass ratio of 5-8:5-2 to obtain an uniform mixture, wherein the cellulose is wood pulp, cotton pulp or bamboo pulp with degree of polymerization of 400 to 1,000; the ionic liquid consists of cations and anions; the cations are substituent-containing alkyl imidazole ions, wherein the substituent is more than one of hydrogen, C1 to C6 alkyl group, ethyl, propenyl, butenyl, ethoxyl, hydroxypropyl and alkoxy groups; the anions are halogen ions, BF4-, PF4-, SCN-, CN-, OCN-, CNO-, CF3SO3-, CFCOO-, CH3COO-, and (CF3SO2)2N- or (CF3SO2)2Cl-; 2, feeding the mixture into a double-screw extruder for melting spinning and stretching the extruded yarn by 0.5 to 6 times; and 3, washing, performing thermal forming and winding to obtain the cellulose fiber.
Description
Technical field
The present invention relates to the preparation method of cellulose fibre, particularly a kind of is plasticizer with the ionic liquid, and adopts melt-spinning technology to prepare the method for cellulose fibre.
Background technology
Cellulose is that nature is vouchsafed the abundantest human natural high molecular substance, and it not only originates abundant, and is reproducible resource.Processing and utilize cellulosic material that world's recycling economy and sustainable development are had positive meaning.Because unmodified cellulose can not fusion, so the solution processing method is the main means of preparation material of regenerated cellulose always.The production of cellulose fibre mainly is viscose process at present, yet this method energy consumption is high, can produce a large amount of waste gas and waste water aborning, and environment is caused substantial pollution.
In recent years, a kind of cellulosic novel solvent ionic liquid has received widely and having paid close attention to.Ionic liquid is meant the ionic compound that is liquid near the temperature range very big room temperature.Because it has interval big, the characteristics such as soluble end is wide, vapour pressure is extremely low, Heat stability is good of fluid temperature, is a kind of ideal solvent of various organic matters, organo-metallic compound, inorganic matter.Ionic liquid still is a kind of solvent that designs; In catalytic reaction; Can ionic liquid be designed to acid or alkalescence, hydrophilic or oleophylic based on concrete demand, in addition can be designed to high-dissolvability to some concrete compounds or low solubility; And ion liquid another characteristics can reuse exactly.Therefore, be that solvent prepares the novel environment-friendly preparation method that cellulose fibre is considered to a kind of alternative viscose process with the ionic liquid.Reported by preparation method's patent documentation of the cellulose fibre of solvent is existing about ionic liquid: for example; The CN101240467A document discloses a kind of blended fiber of cellulose/polyacrylonitrile; It promptly is the cosolvent of cellulose and polyacrylonitrile with the ionic liquid; The preparation core-skin fibre, wet spinning has been adopted in this method spinning; The CN101089249A document discloses a kind of preparation method of cellulose blending fibre, and this method also is with cellulose, chitin/chitosan and ionic liquid blend dissolving and spinning, also belongs to wet spinning; The CN101240454A document discloses a kind of preparation method of blended fiber cellulose fiber, and it carries out wet spinning after mixing the cellulose of different proportion/polyethylene base class high polymer and ion liquid dissolving again; It is the method that solvent prepares cellulose fibre with the ionic liquid that the CN1851063A document has then been reported a kind of, and this method is wet spinning equally.The cellulose solution concentration that method for preparing goes out is all lower, solution concentration the highest also less than 40%.In the scope of applicant's retrieval, be plasticizer with the ionic liquid, and the technology that adopts melt spinning method to prepare cellulose fibre is not then appeared in the newspapers.
Summary of the invention
To the deficiency of prior art, the technical problem that quasi-solution of the present invention is determined is that a kind of preparation method of cellulose fibre is provided; This method is plasticizer with the ionic liquid, adopts the melt-spinning technology preparation, has the efficient height; Technology is simple, and cost savings are low in the pollution of the environment; Be suitable for industrializing implementation, meet characteristics such as low-carbon economy demand for development.
The technical scheme that the present invention solve the technical problem is, designs a kind of preparation method of cellulose fibre, and this preparation method adopts melt-spinning technology, comprises the following steps:
(1) in blender, with cellulose and ionic liquid solution by 5～8: 5～2 mass ratio is processed homogeneous mixture,
Said cellulose is that the degree of polymerization is 400～1000 wood pulp, cotton pulp or bamboo pulp;
Described ionic liquid is made up of CATION and anion, and CATION is for containing substituent alkyl imidazole ion, and wherein substituting group is hydrogen, C
1～C
6Alkyl, vinyl, propenyl, cyclobutenyl, ethoxy, hydroxypropyl, alkoxyl in more than one; Anion is halide ion, BF
4 -, PF
4 -, SCN
-, CN
-, OCN
-, CNO
-, CF
3SO
3 -, CFCOO
-, CH
3COO
-, (CF
3SO
2)
2N
-Or (CF
3SO
2)
2Cl
-
(2) with the mixture feeding twin-screw spinning machine melt spinning that obtains in (1) step; Spinning temperature is 100～170 ℃; Wherein, The temperature of feeding section, melt zone, metering section and head section is respectively 100～110 ℃, and 110～140 ℃, 110～160 ℃ and 120～170 ℃, screw speed is 10～100 rev/mins; Directly hot-stretch in hot dry wind of the fiber filaments of extruding, 80～140 ℃ of hot blast temperatures, draw ratio are 0.5～6 times;
(3) fiber after will stretching is washed, 50～90 ℃ of washing temperature, and HEAT SETTING then, coiling promptly obtain cellulose fibre.
Compared with prior art; The beneficial effect of the inventive method is: 1. adopt suitable ionic liquid for the cellulose plasticizer carries out melt spinning, improved the production efficiency of cellulose fibre, significantly reduced ion liquid use amount (can with the ionic liquid mass content by 70～80% drop to melt spinning 20%); Production process obviously shortens; Process energy consumption and operating cost are low, and help environmental protection, meet the requirement of green production; 2. the prepared cellulose fibre of the inventive method has excellent mechanical intensity, and it is the cellulose fibre of the wet method spinning of solvent with the ionic liquid that its mechanical performance is higher than corresponding.
The specific embodiment
Below in conjunction with specific embodiment, further set forth the present invention.
Preparation method's (abbreviation method) of the cellulose fibre of the present invention's design, this method adopts melt-spinning technology, comprises the following steps:
(1) in blender, with cellulose and ionic liquid solution by 5～8: 5～2 mass ratio is processed homogeneous mixture,
Said cellulose is that the degree of polymerization is 400～1000 wood pulp, cotton pulp or bamboo pulp; For improving mixed effect and efficient, be broken into the size below 1mm * 1mm to cellulose powder before mixing, and then by described mixed;
Described ionic liquid is made up of CATION and anion, and CATION is for containing substituent alkyl imidazole ion, and wherein substituting group is hydrogen, C
1～C
6Alkyl, vinyl, propenyl, cyclobutenyl, ethoxy, hydroxypropyl, alkoxyl in more than one; Anion is halide ion, BF
4 -, PF
4 -, SCN
-, CN
-, OCN
-, CNO
-, CF
3SO
3 -, CFCOO
-, CH
3COO
-, (CF
3SO
2)
2N
-Or (CF
3SO
2)
2Cl
-Preferred ionic liquid is chlorination 1-allyl-3-methylimidazole ([AMIM] Cl), chlorination 1-butyl-3-methylimidazole ([BMIM] Cl), chlorination 1-ethyl-3-methylimidazole ([EMIM] Cl) or acetic acid 1-ethyl-3-methylimidazole ([EMIM] Ac).
Further characteristic of the present invention be when the accounting of ionic liquid in mixture when being lower than 40%, add dimethyl sulfoxide (DMSO) (DMSO), at this moment, the mass ratio of said cellulose: ionic liquid: DMSO is 6～8: 4～2: 0.5～3.3.
It is that the dilution ionic liquid reduces its viscosity that described DMSO mainly acts on, and also can partly play plasticization simultaneously.
(2) with the mixture feeding twin-screw spinning machine melt spinning that obtains in (1) step; Spinning temperature is 100～170 ℃; Wherein, The temperature of feeding section, melt zone, metering section and head section is respectively 100～110 ℃, and 110～140 ℃, 110～160 ℃ and 120～170 ℃, screw speed is 10～100 rev/mins; The fiber filaments of extruding is directly carried out hot-stretch in hot dry wind, 80～140 ℃ of hot blast temperatures, draw ratio are 0.5～6 times;
(3) fiber after will stretching is washed, 50～90 ℃ of washing temperature, and HEAT SETTING then, coiling promptly obtain cellulose fibre.
Key of the present invention is to have adopted conventional method to think the melt spinning that can not prepare cellulose fibre; For making melting method go for the preparation of cellulose fibre; The technical problem that the present invention solved is under the situation that plasticizer adds; Cellulosic fusing point is dropped to below the decomposition temperature, thereby can carry out melt spinning smoothly.Research shows, the adding of small amount of plasticizer can reduce the active force between cellulosic molecule, makes the cellulose melt temperature drop to below the decomposition temperature, and the cellulose of this moment just possibly carry out melt spinning.Concrete technical process is, plasticizer ionic liquid or the ionic liquid that contains dimethyl sulfoxide (DMSO) sneaked in the abundant comminuted fibres element, and mix, and feeds then in the twin-screw spinning machine of suitable process conditions to carry out melt spinning.
The present invention does not address part and is applicable to prior art.
Provide the specific embodiment of the invention below.The meaning of these embodiment only is to illustrate practical implementation method of the present invention, and the protection domain of unrestricted application claim of the present invention.
Embodiment 1
To pulverize the degree of polymerization below 1mm * 1mm and be 530 wood pulps 300g and 300g [AMIM] Cl ionic liquid and in blender, stir into homogeneous mixture, and feed the double screw extruder melt spinning then, feeding section temperature is made as 100 ℃; Melt zone, metering section and head section temperature are respectively 110 ℃, 130 ℃ and 140 ℃, and rotating speed is 10 rev/mins, open vacuum gas extraction system after the discharging; Through measuring pump and spinning head; The cellulose thread carries out xeothermic stretching through the hot blast path, 80 ℃ of path hot blast temperatures, 2 times of draw ratios; Fiber after the stretching gets into water bath and washes; 50 ℃ of washing temperature are carried out conventional HEAT SETTING and coiling then, promptly obtain fiber of the present invention.Through detecting, the TENSILE STRENGTH of gained cellulose fibre is 3.87cN/dtex.
Embodiment 2
To be crushed to the degree of polymerization below 1mm * 1mm and be 530 wood pulps 300g and 200g [AMIM] Cl and 25gDMSO and in blender, stir, and feed double screw extruder then, feeding section temperature is made as 110 ℃; Melt zone, metering section and head section temperature are respectively 130 ℃, 150 ℃ and 160 ℃, and rotating speed is 20 rev/mins, open vacuum gas extraction system after the discharging; Through measuring pump and spinning head, the cellulose thread carries out xeothermic stretching through the hot blast path, and wherein the path hot blast temperature is 140 ℃; 0.5 times of draw ratio; The back fiber that stretches gets into water bath and washes, and 80 ℃ of washing temperature are carried out HEAT SETTING, coiling then; Promptly obtain described fiber, its TENSILE STRENGTH is 4.12cN/dtex.
Embodiment 3
To be crushed to the degree of polymerization below 1mm * 1mm and be 1000 bamboo pulp 400g and 300g [BMIM] Cl ionic liquid and in blender, mix, feed double screw extruder then.Feeding section temperature is made as 110 ℃, and melt zone, metering section and head section temperature are respectively 130 ℃, 145 ℃ and 150 ℃, and rotating speed is 30 rev/mins; Open vacuum gas extraction system after the discharging, through measuring pump and spinning head, the cellulose thread carries out xeothermic stretching through the hot blast path; Wherein the path hot blast temperature is 120 ℃, 3.2 times of draw ratios, and the back fiber that stretches gets into water bath and washes; 90 ℃ of washing temperature; Carry out HEAT SETTING, coiling then, promptly obtain described fiber, its TENSILE STRENGTH is 4.53cN/dtex.
Embodiment 4
To be crushed to the degree of polymerization below 1mm * 1mm and be 800 cotton pulp dregs of rice 300g and 200g [BMIM] Cl ionic liquid and DMSO25g and in blender, mix, and feed double screw extruder then, feeding section temperature is made as 100 ℃; Melt zone, metering section and head temperature are respectively 120 ℃, 130 ℃ and 140 ℃, and rotating speed is 30 rev/mins, open vacuum gas extraction system after the discharging; Through measuring pump and spinning head, the cellulose thread carries out xeothermic stretching through the hot blast path, and wherein the path hot blast temperature is 120 ℃; 2.5 times of draw ratios; The back fiber that stretches gets into water bath and washes, and 90 ℃ of washing temperature are carried out HEAT SETTING, coiling then; Promptly obtain described fiber, its TENSILE STRENGTH is 4.17cN/dtex.
Embodiment 5
To be crushed to the degree of polymerization below 1mm * 1mm and be 530 wood pulps 800g and 200g [EMIM] Ac ionic liquid and 330gDMSO and in blender, stir, and feed double screw extruder then, feeding section temperature is made as 110 ℃; Melt zone, metering section and head section temperature are respectively 145 ℃, 160 ℃ and 170 ℃, and rotating speed is 100 rev/mins, open vacuum gas extraction system after the discharging; Through measuring pump and spinning head, the cellulose thread carries out xeothermic stretching through the hot blast path, and wherein the path hot blast temperature is 120 ℃; 6 times of draw ratios; The back fiber that stretches gets into water bath and washes, and 90 ℃ of washing temperature are carried out HEAT SETTING, coiling then; Promptly obtain described fiber, its TENSILE STRENGTH is 4.57cN/dtex.
Embodiment 6
To be crushed to the degree of polymerization below 1mm * 1mm and be 530 wood pulps 300g and 300g [EMIM] Cl ionic liquid and in blender, stir, and feed double screw extruder then, feeding section temperature is made as 110 ℃; Melt zone, metering section and head section temperature are respectively 135 ℃, 145 ℃ and 155 ℃, and rotating speed is 60 rev/mins, open vacuum gas extraction system after the discharging; Through measuring pump and spinning head, the cellulose thread carries out xeothermic stretching through the hot blast path, and wherein the path hot blast temperature is 120 ℃; 4.5 times of draw ratios; The back fiber that stretches gets into water bath and washes, and 70 ℃ of washing temperature are carried out HEAT SETTING, coiling then; Promptly obtain described fiber, its TENSILE STRENGTH is 4.23cN/dtex.
Claims (4)
1. the preparation method of a cellulose fibre, this preparation method adopts melt-spinning technology, comprises the following steps:
(1) in blender, with cellulose and ionic liquid solution by 5～8: 5～2 mass ratio is processed homogeneous mixture,
Described cellulose is that the degree of polymerization is 400～1000 wood pulp, cotton pulp or bamboo pulp;
Described ionic liquid is made up of CATION and anion, and CATION is for containing substituent alkyl imidazole ion, and wherein substituting group is hydrogen, C
1～C
6Alkyl, vinyl, propenyl, cyclobutenyl, ethoxy, hydroxypropyl, alkoxyl in more than one; Anion is halide ion, BF
4 -, PF
4 -, SCN
-, CN
-, OCN
-, CNO
-, CF
3SO
3 -, CFCOO
-, CH
3COO
-, (CF
3SO
2)
2N
-Or (CF
3SO
2)
2C1
-
(2) with the mixture feeding twin-screw spinning machine melt spinning that obtains in (1) step; Spinning temperature is 100～170 ℃; Wherein, The temperature of feeding section, melt zone, metering section and head section is respectively 100～110 ℃, and 110～140 ℃, 110～160 ℃ and 120～170 ℃, screw speed is 10～100 rev/mins; Directly hot-stretch in hot dry wind of the fiber filaments of extruding, 80～140 ℃ of hot blast temperatures, draw ratio are 0.5～6 times;
(3) fiber after will stretching is washed, 50～90 ℃ of washing temperature, and HEAT SETTING then, coiling promptly obtain cellulose fibre.
2. according to the preparation method of the said cellulose fibre of claim 1, it is characterized in that described ionic liquid is chlorination 1-allyl-3-methylimidazole, chlorination 1-butyl-3-methylimidazole, chlorination 1-ethyl-3-methylimidazole or acetic acid 1-ethyl-3-methylimidazole.
3. according to the preparation method of the said cellulose fibre of claim 1, be broken into the size below 1mm * 1mm to cellulose powder before it is characterized in that mixing.
4. according to the preparation method of claim 1,2 or 3 said cellulose fibres; It is characterized in that when the accounting of ionic liquid in mixture when being lower than 40%; Add dimethyl sulfoxide (DMSO), cellulose: ionic liquid: the mass ratio of dimethyl sulfoxide (DMSO) is 6～8: 4～2: 0.5～3.3.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010101647735A CN101838861B (en) | 2010-05-07 | 2010-05-07 | Method for preparing cellulose fiber |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2010101647735A CN101838861B (en) | 2010-05-07 | 2010-05-07 | Method for preparing cellulose fiber |
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|---|---|
| CN101838861A CN101838861A (en) | 2010-09-22 |
| CN101838861B true CN101838861B (en) | 2012-07-04 |
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| CN2010101647735A Expired - Fee Related CN101838861B (en) | 2010-05-07 | 2010-05-07 | Method for preparing cellulose fiber |
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Families Citing this family (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102002762A (en) * | 2010-11-02 | 2011-04-06 | 山东海龙股份有限公司 | Method for preparing high-strength special-shape cellulose fiber |
| CN102477591B (en) * | 2010-11-19 | 2013-12-11 | 中国纺织科学研究院 | Cellulose fiber, preparation method thereof and equipment |
| CN102154720A (en) * | 2010-12-21 | 2011-08-17 | 天津工业大学 | Preparation method of cellulose fibres |
| CN102619026A (en) * | 2012-04-20 | 2012-08-01 | 天津工业大学 | Preparation method of nano micro cellulose fiber non-woven fabric |
| CN102964524B (en) * | 2012-11-28 | 2015-05-13 | 东华大学 | Method for extruding in-situ grafting modified cellulose through twin screws with ionic liquid serving as solvent |
| CN103014892B (en) * | 2012-12-26 | 2014-10-22 | 东华大学 | Preparation method of cellulose acetate fiber |
| CN103173932A (en) * | 2013-03-20 | 2013-06-26 | 天津工业大学 | Preparation method of antiflaming cellulose non-woven cloth |
| CN103147145A (en) * | 2013-03-20 | 2013-06-12 | 天津工业大学 | Method for preparing modified cellulose fire-retardant fiber through reaction extrusion |
| CN103305952B (en) * | 2013-05-03 | 2017-02-08 | 天津工业大学 | Preparation of cellulose spinning solution |
| CN103966695B (en) * | 2014-04-23 | 2016-02-10 | 安徽依采妮纤维材料科技有限公司 | A kind of health care ramee fabric and preparation method thereof |
| CN104047068A (en) * | 2014-07-04 | 2014-09-17 | 天津工业大学 | Method for preparing modified cellulose antibacterial fibers through reaction extrusion |
| CN104194059B (en) * | 2014-08-08 | 2017-07-11 | 华中科技大学 | A kind of cellulose thermoplastic material and preparation method thereof |
| CN106149083B (en) * | 2015-04-02 | 2018-05-15 | 恒天海龙（潍坊）新材料有限责任公司 | Functional graphene cellulose fiber prepared by melting method and preparation method thereof |
| CN106567150A (en) * | 2016-11-04 | 2017-04-19 | 天津工业大学 | Preparation method of plasticized cellulose carbamate fiber |
| CN109594150A (en) * | 2018-12-26 | 2019-04-09 | 李宁（中国）体育用品有限公司 | The foam material of polyester cotton prepares and regeneration spinning forming method |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1920128A (en) * | 2006-09-12 | 2007-02-28 | 太原市伦嘉生物工程科技有限公司 | Novel function flame-proof fibre and preparation method thereof |
-
2010
- 2010-05-07 CN CN2010101647735A patent/CN101838861B/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1920128A (en) * | 2006-09-12 | 2007-02-28 | 太原市伦嘉生物工程科技有限公司 | Novel function flame-proof fibre and preparation method thereof |
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