CN103255500A - Preparation method of polyurethane elastic fiber suitable for low-temperature setting - Google Patents
Preparation method of polyurethane elastic fiber suitable for low-temperature setting Download PDFInfo
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- CN103255500A CN103255500A CN2013102119523A CN201310211952A CN103255500A CN 103255500 A CN103255500 A CN 103255500A CN 2013102119523 A CN2013102119523 A CN 2013102119523A CN 201310211952 A CN201310211952 A CN 201310211952A CN 103255500 A CN103255500 A CN 103255500A
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Abstract
The invention relates to a preparation method of polyurethane elastic fiber suitable for low-temperature setting. The preparation method uses one or more of N-methylethylenediamine, N-ethylethylenediamine, and N-isopropyl-1,3-propanediamine, the content of which is 20-80 mole% of a chain extender, wherein the chain expander further comprises one or more of ethylenediamine, 1,2-propanediamine, 1,3-propanediamine, hexamethylenediamine or 2-methylpentanediamine. The polyurethane elastic fiber prepared by the preparation method provided by the invention has excellent heat setting efficiency below the setting temperature of 170 DEG C; and compared with the prior art, when the polyurethane elastic fiber prepared by the preparation method provided by the invention is woven with heat sensitive fiber, the obtained product can be heat-set at a temperature lower than 170 DEG C, and has excellent heat-setting efficiency, so that the field of spandex application is broadened.
Description
Technical field
The present invention relates to a kind of preparation method of polyurethane elastomeric fiber of suitable low temperature setting, concrete providing a kind ofly has the preparation method of the polyurethane elastomeric fiber of higher heat-set efficiency at setting temperature below 170 ℃, belong to the technical field that a kind of macromolecular material is made.
Background technology
Polyurethane elastomeric fiber has characteristics such as resilience height, fracture strength are big, elongation at break height, and is widely used in the multiple field.Along with the continuous expansion of its purposes, the client is also more and more higher to the requirement of elastomer.
Generally, polyurethane elastomeric fiber can be at high temperature in last handling process (about 190 ℃) carry out heat setting, and high temperature can cause thermal sensitivity fiber generation thermal degradation, as nylon, wool, polypropylene, artificial silk, cotton yarn etc.When wool, cotton yarn, nylon mixed goods need carry out heat setting at a lower temperature, and fabric can not reach suitably and heat setting effectively.Make the comfort level variation of fabric for the generation that prevents high temperature degradation and fabric do not have effectively setting, how at present a lot of research institutions all carry out heat setting to polyurethane elastomeric fiber in research under lower temperature.
Present existing more relevant report, United States Patent (USP) 5539037 is disclosed in the low concentration alkali metal carboxylate and rhodanate increases its heat-set efficiency, but this salt decomposes easily and reduces its effect in following process.A kind of additive that comprises quaternary amine of United States Patent (USP) 6403682B1 public use improves heat setting, but the setting temperature of this method is higher, can't satisfy the setting temperature of the elastomer that contains wool.United States Patent (USP) 5000899 and 5948875 public use 2-methyl isophthalic acids, 5-pentanediamine increase the heat-set efficiency of polyurethane elastomeric fiber as chain extender.Patent CN1273510C announces the chain extender that uses the ortho position to replace vulcabond and big molecule diamines, improves heat-set efficiency.Contain adding part tetramethylene ether or 1,2-propylidene ether in the patent 00816584.X public use copolymerization alkylene ether and improve heat-set efficiency.Japan Patent JP08-020625, JP08-176268 disclose 2 of the different amounts of using with United States Patent (USP) 3631138,5879799, and 4 '-MDI improves heat-set efficiency.
But the set efficiency of these patents preferably temperature all about 170 ℃ or more than, can't satisfy the more requirement of the thermal sensitivity fiber of low temperature setting of some needs, and there are not public use chain extender N-methyl ethylenediamine, N-ethylethylenediamine, N-isopropyl-1, the 3-propane diamine.
Summary of the invention
Technical problem: the preparation method who the purpose of this invention is to provide a kind of polyurethane elastomeric fiber of suitable low temperature setting.
Technical scheme: the preparation method of the polyurethane elastomeric fiber of a kind of suitable low temperature setting of the present invention may further comprise the steps:
A). polytetramethylene ether diol PTMG and 4,4-diphenyl methane MDI react among the N-dimethylacetylamide DMAC at solvent N, the preparation prepolymer solution;
B). after prepolymer solution was cooled to 8～15 ℃, the DMAC solution that adds chain extender and reaction controlling agent in the prepolymer solution carried out chain extending reaction, obtains high molecular weight polymers solution;
C). add anti-flavescence agent, antioxidant, ultra-violet absorber in the heavy polymer solution that obtains, lubricatedly discongest agent, fully mix preparation polyurethane spinning solution;
D). prepared polyurethane spinning solution is obtained polyurethane elastomeric fiber by dry spinning.
The mol ratio of described MDI and PTMG is 1.8:1～2.2:1.
Described chain extender comprises two parts, and first comprises N-methyl ethylenediamine, N-ethylethylenediamine, N-isopropyl-1, and one or more of 3-propane diamine, this content are 20%～80% of chain extender total mole number; The second portion of described chain extender comprises ethylenediamine, 1,2-propane diamine, 1, one or more in 3-propane diamine, hexamethylene diamine or the 2 methyl pentamethylenediamine.
Described reaction controlling agent comprises one or both mixture of diethylamine and monoethanolamine, and its addition is 0.2wt%～0.8wt% of polytetramethylene ether diol PTMG.
Beneficial effect: compared with prior art, polyurethane elastomeric fiber and the thermal sensitivity fiber interweaving of the present invention's preparation can carry out heat setting under than 170 ℃ of lower temperature, and have excellent heat-set efficiency, widen the spandex Application Areas.
The specific embodiment
The present invention adopts N-methyl ethylenediamine, N-ethylethylenediamine, the N-isopropyl-1 that contains 20 moles of %～80 mole % at least, one or more chain extender of 3-propane diamine prepares and is adapted at setting temperature below 170 ℃, and has the polyurethane elastomeric fiber of higher set efficiency.
Method provided by the invention is as follows:
1 polytetramethylene ether diol (PTMG) and 4,4-diphenyl methane (MDI) are at solvent N, and reaction in the dinethylformamide (DMAC) prepares prepolymer solution;
38～50 ℃ of described reaction temperatures;
Described reaction time 60～180min;
The mol ratio of described MDI and PTMG is 1.8:1～2.2:1.
2 after prepolymer solution is cooled to 8～15 ℃, and the DMAC solution that adds chain extender and reaction controlling agent carries out chain extending reaction, obtains high molecular weight polymers solution;
Described chain extender comprises N-methyl ethylenediamine, N-ethylethylenediamine, N-isopropyl-1, and one or more of 3-propane diamine, its content are 20 moles of %～80 mole % of chain extender.
Described chain extender also comprises ethylenediamine, 1,2-propane diamine, 1, one or more in 3-propane diamine, hexamethylene diamine or the 2 methyl pentamethylenediamine;
One or both of described amine reaction controlling agent diethylamine and monoethanolamine, its addition is 0.2wt%～0.8wt% of PTMG.
The DMAC solution of described chain extender and amine reaction controlling agent, its concentration is 3～9wt%.
3 add anti-flavescence agent, antioxidant, ultra-violet absorber in the heavy polymer solution that obtains, lubricatedly discongest agent, fully mix preparation polyurethane spinning solution;
Described anti-flavescence agent is two (N, N-dimethyl hydrazides amino, 4-phenyl) methane, the manufacturer: the two keys in Taiwan, its consumption is the 0.2wt%～1.5wt% of amount of polymers.
Described antioxidant is cyamelide, the manufacturer: Taiwan cyanogen spy, its consumption is the 0.5wt%～1.5wt% of amount of polymers.
Described ultraviolet-resistant absorbent is 2-(2 '-hydroxyl-3 ', 5 '-two tertiary pentyls)-benzotriazole, the manufacturer: the two keys in Taiwan, its consumption is the 0.1wt%～1.0wt% of amount of polymers.
Described lubricated to discongest agent be dolomol, and the manufacturer: Japanese grease, its consumption are the 0.1wt%～1.0wt% of amount of polymers.
Described polyurethane spinning solution viscosity is 3000-10000piose.
Described polyurethane spinning solution concentration is 28～40%
4 obtain polyurethane elastomeric fiber with prepared polyurethane spinning solution by dry spinning.
Described dry-spinning spinning shaft temperature is 245～260 ℃;
Described dry-spinning spinning speed is 500～1000m/min, preferred 600～800m/min.
Describe its production process of the present invention in detail with embodiment below, but these embodiment must not be interpreted as the limitation of the present invention that goes up in all senses.
Embodiment 1:
Add the 9.0kg number-average molecular weight and be 1810 PTMG in the reactor of agitator is housed and mixes with 5.5kgDMAC, the MDI of adding 2.486kg behind the reactive polymeric 135min, adds 12.8kgDMAC conciliation prepolymer concentration then.
Add then and contain 84.8g(0.962mol) N-ethylethylenediamine, 231g(3.850mol) ethylenediamine and the DMAC solution of the diethylamine of 23.4g carry out chain extending reaction, add at last that the anti-flavescence agent of 0.7 weight %, 1.0 weight % antioxidants, 0.35 weight % ultra-violet absorber, 0.3 weight % are lubricated discongests agent and obtain spinning solution, its original liquid concentration is 35%, forms the spandex silk by dry spinning after slaking, deaeration, filtration.Dry spinning is spun into the polyurethane elastomeric fiber of 20D (Denier).Detect its heat-set efficiency then.
The heat-set efficiency detection mode: with polyurethane elastomeric fiber drawing-off 100%(from 150mm to 300mm) after, 150 ℃ of following dry heat-settings 1 minute, then fiber is cooled to room temperature, measure its fibre length, and calculate its heat-set efficiency according to following formula:
Heat-set efficiency (%)={ (length-initial length after the heat setting)/(length-initial length after the drawing-off) } * 100%
Embodiment 2
Prepare polyurethane elastomeric fiber according to embodiment 1 is described with quadrat method, difference is to add 212.1g(2.406mol) N-ethylethylenediamine, 144.4g(2.406mol) ethylenediamine and the DMAC solution of the diethylamine of 23.4g carry out chain extending reaction.
Embodiment 3
Prepare polyurethane elastomeric fiber according to embodiment 1 is described with quadrat method, difference is to add 339.4g(3.850mol) N-ethylethylenediamine, 57.7g(0.962mol) ethylenediamine and the DMAC solution of the diethylamine of 23.4g carry out chain extending reaction.
Embodiment 4
Prepare polyurethane elastomeric fiber according to embodiment 1 is described with quadrat method, difference is to add 212.1g(2.406mol) N-ethylethylenediamine, 72.2g(1.203mol) ethylenediamine, 89g(1.203mol) 1, the DMAC solution of the diethylamine of 2-propane diamine and 23.4g carries out chain extending reaction.
Embodiment 5 to 8 and Comparative Examples 1 to 3
Prepare polyurethane elastomeric fiber according to embodiment 1 is described with quadrat method, difference is that variation has taken place for molar percentage (mol%) and the kind of MDI/PTMG mol ratio as shown in table 1 and chain extender.
Table 1:
Shown in last table 1: with N-methyl ethylenediamine, N-ethylethylenediamine, the N-isopropyl-1 of 20 moles of %～80 mole %, the 3-propane diamine is that the heat-set efficiency of the polyurethane elastomeric fiber of chain extender preparation has obvious raising.
Claims (4)
1. the preparation method of the polyurethane elastomeric fiber of a suitable low temperature setting is characterized in that this method may further comprise the steps:
A). polytetramethylene ether diol PTMG and 4,4-diphenyl methane MDI react among the N-dimethylacetylamide DMAC at solvent N, the preparation prepolymer solution;
B). after prepolymer solution was cooled to 8～15 ℃, the DMAC solution that adds chain extender and reaction controlling agent in the prepolymer solution carried out chain extending reaction, obtains high molecular weight polymers solution;
C). add anti-flavescence agent, antioxidant, ultra-violet absorber in the heavy polymer solution that obtains, lubricatedly discongest agent, fully mix preparation polyurethane spinning solution;
D). prepared polyurethane spinning solution is obtained polyurethane elastomeric fiber by dry spinning.
2. the preparation method of the polyurethane elastomeric fiber of a kind of suitable low temperature setting according to claim 1, the mol ratio that it is characterized in that described MDI and PTMG is 1.8:1～2.2:1.
3. the preparation method of the polyurethane elastomeric fiber of a kind of suitable low temperature setting according to claim 1, it is characterized in that described chain extender comprises two parts, first comprises N-methyl ethylenediamine, N-ethylethylenediamine, N-isopropyl-1, one or more of 3-propane diamine, this content are 20%～80% of chain extender total mole number; The second portion of described chain extender comprises ethylenediamine, 1,2-propane diamine, 1, one or more in 3-propane diamine, hexamethylene diamine or the 2 methyl pentamethylenediamine.
4. the preparation method of the polyurethane elastomeric fiber of a kind of suitable low temperature setting according to claim 1, it is characterized in that described reaction controlling agent comprises one or both mixture of diethylamine and monoethanolamine, its addition is 0.2wt%～0.8wt% of polytetramethylene ether diol PTMG.
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103590138A (en) * | 2013-11-06 | 2014-02-19 | 浙江华峰氨纶股份有限公司 | Preparation method for anti-flaming polyurethane elastic fiber |
| CN103710786A (en) * | 2013-12-18 | 2014-04-09 | 浙江华峰氨纶股份有限公司 | Preparation method of polyurethane raw liquid for high-speed spinning |
| CN104278354A (en) * | 2014-10-28 | 2015-01-14 | 浙江华峰氨纶股份有限公司 | Preparation method of flesh-colored spandex |
| CN104651974A (en) * | 2015-03-13 | 2015-05-27 | 浙江华峰氨纶股份有限公司 | Superfine denier polyurethane fiber and preparation method thereof |
| CN104726960A (en) * | 2013-12-20 | 2015-06-24 | 浙江华峰氨纶股份有限公司 | Polyurethane elastic fiber with improved heat-setting performance, and preparation method thereof |
| CN103668544B (en) * | 2013-12-11 | 2016-01-13 | 浙江华峰氨纶股份有限公司 | A kind of polyurethane elastomeric fiber with multielement functionality and preparation method thereof |
| CN105506777A (en) * | 2016-01-26 | 2016-04-20 | 浙江华峰氨纶股份有限公司 | Polyurethane elastic fiber easy to adhere and preparation method thereof |
| CN105603583A (en) * | 2015-12-30 | 2016-05-25 | 浙江华峰氨纶股份有限公司 | Spandex with fatigue resistance and meltability and preparing method thereof |
| CN109610039A (en) * | 2018-12-04 | 2019-04-12 | 浙江华峰氨纶股份有限公司 | A kind of preparation method with high fever set efficiency polyurethaneurea elastic fiber |
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| CN102899740A (en) * | 2012-11-09 | 2013-01-30 | 浙江华峰氨纶股份有限公司 | Method for preparing low-temperature finalizing polyurethane elastic fiber |
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| US4973647A (en) * | 1989-05-31 | 1990-11-27 | E. I. Du Pont De Nemours And Company | Fiber from polyether-based spandex |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103590138A (en) * | 2013-11-06 | 2014-02-19 | 浙江华峰氨纶股份有限公司 | Preparation method for anti-flaming polyurethane elastic fiber |
| CN103668544B (en) * | 2013-12-11 | 2016-01-13 | 浙江华峰氨纶股份有限公司 | A kind of polyurethane elastomeric fiber with multielement functionality and preparation method thereof |
| CN103710786A (en) * | 2013-12-18 | 2014-04-09 | 浙江华峰氨纶股份有限公司 | Preparation method of polyurethane raw liquid for high-speed spinning |
| CN104726960A (en) * | 2013-12-20 | 2015-06-24 | 浙江华峰氨纶股份有限公司 | Polyurethane elastic fiber with improved heat-setting performance, and preparation method thereof |
| CN104278354A (en) * | 2014-10-28 | 2015-01-14 | 浙江华峰氨纶股份有限公司 | Preparation method of flesh-colored spandex |
| CN104651974A (en) * | 2015-03-13 | 2015-05-27 | 浙江华峰氨纶股份有限公司 | Superfine denier polyurethane fiber and preparation method thereof |
| CN105603583A (en) * | 2015-12-30 | 2016-05-25 | 浙江华峰氨纶股份有限公司 | Spandex with fatigue resistance and meltability and preparing method thereof |
| CN105603583B (en) * | 2015-12-30 | 2017-10-24 | 浙江华峰氨纶股份有限公司 | A kind of spandex with endurance and fusible characteristic and preparation method thereof |
| CN105506777A (en) * | 2016-01-26 | 2016-04-20 | 浙江华峰氨纶股份有限公司 | Polyurethane elastic fiber easy to adhere and preparation method thereof |
| CN109610039A (en) * | 2018-12-04 | 2019-04-12 | 浙江华峰氨纶股份有限公司 | A kind of preparation method with high fever set efficiency polyurethaneurea elastic fiber |
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Address after: No. 1788, Dongshan Economic Development Zone, Ruian, Wenzhou, Zhejiang Patentee after: Huafeng Chemical Co.,Ltd. Address before: No. 1788, Dongshan Economic Development Zone, Ruian, Wenzhou, Zhejiang Patentee before: ZHEJIANG HUAFENG SPANDEX Co.,Ltd. |