CN1664188A - Micro-polyurethane short fiber - Google Patents
Micro-polyurethane short fiber Download PDFInfo
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- CN1664188A CN1664188A CN 200510023908 CN200510023908A CN1664188A CN 1664188 A CN1664188 A CN 1664188A CN 200510023908 CN200510023908 CN 200510023908 CN 200510023908 A CN200510023908 A CN 200510023908A CN 1664188 A CN1664188 A CN 1664188A
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Abstract
This invention refers to a super thin polyurethane short fiber and preparation method .The short fiber is island composite fiber, the odd fiber density is 6~10dtex, fiber rupture intensity 1.9~2.1CN/dtex, rupture elongate rate is 100~160%, island apart odd fiber degree is 0.05~0.3dtex. The polyurethane is element of island, low density polyethylene is element of sea, adopt double screw island composite filature method to produce. In this method, technics is simple and fit to industrialization produce.
Description
Technical field
The present invention relates to a kind of chemical fibre, is a kind of elastic polyurethane composite short fiber and preparation method of super fine denier furtherly.
Background technology:
Islands-in-sea bicomponent fibre is a new technology of making superfine fibre, and to be a kind of polymer be distributed among the another kind of polymer (being referred to as the sea) with the form of a plurality of superfine fentos (being referred to as the island) for it.After this fibrid was made woven fabric or knitted fabric, with the sea component dissolving, the island component fento of staying in the fabric just became superfine fibre.Islands-in-sea bicomponent fibre by the fusion respectively of twin-screw composite spinning machine, enters the fabric of island-in-sea type spinning pack by two kinds of polymer, by runner separately, converges in the spinneret orifice porch, in the lump extrusion molding.Produce with the island method wash, superfine fibre such as brocade, as far back as just existing production of nineteen seventies.But,, make the dissolving of sea component more convenient, so the development of islands-in-sea type fibre is rapider because water-soluble polyester is synthetic to the twentieth century later stage.This chemical fibre new product, fiber is very thin, and the island is separated the back filament number and can be reached below the 0.1dtex, and gained synthetic leather, artificial leather, woven fabric and knitted fabric particularly soft are the important source material of senior textiless such as imitative chamois leather, peach face.But this class islands-in-sea type fibre does not have elasticity, in the Application Areas of elastic fabric certain limitation is arranged.
Spandex has superior elasticity, is widely used in fields such as knitted underwear, pantyhose, elasticity silk stocking, sweat shirt, Lingerie, stocking blank.It is that polyurethane is made elastomer by spin processes such as dry method, wet methods.Spin the technology of having released molten spinning manufacturing spandex the day of Japan in 1967 clearly.In recent years, this technology reaches its maturity, and its advantage is that equipment is simple, small investment, and instant effect does not use solvent, and non-environmental-pollution is promising spandex fiber technology.Spandex is the (synthetic fiber industry: 22 (2), 17～19,1999 of the best elastomer of present various combination property; 22 (3), 38～40,1999; 23 (1), 37～40,2000; 23 (4), 50～52,2000; 23 (6), 22～25,2000; Synthetic fiber, 28 (5), 25～28,2000).Yet because polyurethane melt viscoplasticity is bigger, the melt thread is spinning journey refinement difficulty.As take to improve melt temperature and reduce viscoplasticity, be subjected to the restriction of heat endurance again.Therefore polyurethane is made fine denier filament certain technical difficulty.On the other hand, polyurethane easily produces bonding in becoming fine process, so few hole silk of the most spinning of spandex or single hole silk, and filament number is bigger, has 5～6dtex at least.Spandex staple fibre product is very rare, the high elasticity elongation of this and spandex, after spin a difficult problem of running in the combing much relations also arranged.
Summary of the invention:
The object of the invention provides a kind of micro-polyurethane short fiber.Be a kind of composite short fiber furtherly.
Another purpose of the present invention provides a kind of preparation method of above-mentioned micro-polyurethane short fiber.
Micro-polyurethane short fiber of the present invention is the island component by polyurethane, and low density polyethylene (LDPE) is the ultra-fine denier polyurethane composite short fiber that sea component constitutes, and the weight ratio of polyurethane and low density polyethylene (LDPE) is 1: 0.4～1.5.The filament number of this fiber was 0.05～0.3dtex after separated on the island.
Because polyurethane melt viscoplasticity height influences into the refinement of fine process.Because of frictional force between the fiber is big, easily produce problems such as adhesion, doubling again, become the obstacle of making the polyurethane fiber thin denier silk.Spandex is if make staple fibre, and elastic elongation of its height is brought very big difficulty to the weaving combing of back road.And common brocade, islands-in-sea type fibre such as wash, though can make superfine fibre, polymer itself lacks flexibility, and therefore is not suitable for the raw material as the elastic composite superfine fibre.
The twin-screw island composite short fiber spinning process that the present invention adopts, in two kinds of polymer melt processing, flexible polyurethane melt is surrounded by stiff polyethylene melt, has reduced the viscoplasticity of melt on the whole.In each root composite fibre, the polyurethane melt is split into ten multiplies to tens of strands of continuous threads, and by the quantity decision number of share of stock on spinnerets island, per share thread is among the encirclement of polyethylene melt, merging and the adhesion that polyurethane melts the body thread is blocked, created condition for making the super fine denier spandex.On the other hand, because the mixing of stiff polyethylene composition, the high-tension that the high resilience of polyurethane fiber is produced in drawing process is alleviated, and helps tensile fiber and attenuates.More than some all is an advantage of making ultra-fine spandex staple fibre.The fracture strength of the general spandex of intensity of road, back stretching can raising fiber is 0.8～1.3CN/dtex on the other hand, and sea-island staple fiber fracture strength of the present invention is 1.9～2.1CN/dtex, also provides better fibre property to non-woven and the processing of weaving back.The present invention is aspect the coupling of raw material components, and selecting low density polyethylene (LDPE) is the component in sea, can be solvent with toluene, extract, and this solvent does not influence polyurethane, and two components do not react in spinning process simultaneously, and the spinning temperature aspect is more approaching.
(1) process route of the present invention as shown in Figure 1.
(2) raw material:
The raw material that the present invention adopts is that the raw material of melt spun spandex is a linear polyesters type polyurethane elastomer (TPU).It is to be that 1000～2000 polyester-diol aggregates into performed polymer by vulcabond (MDI) and molecular weight, is chain extender with 1,4 butanediol or 1,6 hexylene glycol, aggregates into the block copolymer that soft chain segment and hard segment replace.PAUR (TPU) elastomer that the present invention adopts is as the island component.Section hardness 77 Shao A, density 1.13g/cm
3, 160 ℃ of fusing points, 250 ℃ of beginnings of heat decomposition temperature.
The alternative condition of sea component is 1. easily to be dissolved in certain solvent, but this solvent dissolve polyurethane not; 2. do not react with polyurethane; 3. spinning temperature and polyurethane are approaching.Select according to above requirement.According to test situation, the employing melt index is 26～50 low density polyethylene (LDPE) section, 108 ℃ of fusing points, 80 ℃ of softening points, density 0.92g/cm
3
(3) spinning equipment:
The present invention uses the test of twin-screw composite spinning machine, and the island spinning plate can be adjusted its plate footpath, aperture, hole count and island number as required.The specification of Cai Yonging in an embodiment: aperture * hole count * island number is 0.3mm * 16 * 16.Each district of screw rod and spin manifold temperature are controlled automatically.Screw rod and measuring pump are by variable frequency regulating speed control.
(4) technological parameter:
1. chip drying
Polyurethane section: use vacuum drying chamber, 90～95 ℃ of baking temperatures;
Vacuum 6 * 10
-2Pa, 48 hours time.The section moisture content is controlled at below 0.01%;
Low density polyethylene (LDPE) section: because polyethylene itself is not moisture, carry out smoothly, with 70 ℃ of heated-air drying a few hours, with the moisture content removal of slice surface absorption in order to ensure spinning.
2. spinning technology parameter
The raw material weight proportioning: polyurethane/polyethylene weight ratio is 1: 0.4～1.5;
Measuring pump specification: 0.6ml/rep;
The measuring pump rotating speed: calculate according to finished product fiber number, proportioning raw materials, spinning speed, stretching ratio, the polyurethane fusant density is with 1.0g/cm
3, polyethylene melt density is with 0.85g/cm
3Calculate;
Screw speed: according to the melt viscosity situation, the TPU screw pressure is higher, is adjusted to 60～100kg/cm
2, screw speed 10～20rep/min.The LDPE screw pressure is lower, is adjusted to 40～60kg/cm
2, screw speed is 20～30rep/min;
Spinning speed: 300～800m/min;
Spinning temperature: TPU is 180～245 ℃;
LDPE is 170～275 ℃;
Chilling temperature: 10～20 ℃.
3. winding process parameter
Draw-off godet speed: 300～800m/min;
Upper oil-pan rotating speed: 18～20rep/min;
Oil concentration: the aqueous solution of 12～15% spandex oil agents (w/w);
Winding speed: 300～800m/min.
4. after-processing technology parameter
Boundling dawn number: 4～4.5 ten thousand dawn;
Immersion cell oil concentration: the aqueous solution of 8～10% spandex oil agents (w/w);
First drawing roller speed: the 20m/min;
Second drawing roller speed: 60～90m/min;
Drawing-off medium: air;
Drawing temperature: room temperature;
Drafting multiple: 3～4 times;
Curling preheating cabinet temperature: 65～70 ℃;
Crimping machine speed: 64m/min;
Curling cold oil temperature: room temperature;
Relaxation heat setting temperature: 70～75 ℃;
The relaxation heat setting time: 10min;
Cutting machine speed: 25m/min;
Shearing length: 38～64mm.
(5) fibrous finished product performance
1. the fine density of monofilament (dtex) 6.0～10.0, it is 0.05～0.3dtex that the back filament number is separated on the island;
2. fracture strength (CN/dtex) 1.9～2.1;
3. elongation at break (%) 126.6;
4. 100% elastic recovery rate (%) 99;
5. 100% elastic recovery rate (%) 90 behind the relaxation heat setting;
6. crimp percent (%) 11.8;
7. crispation number (individual/25mm) 5.2;
8. moisture content (%) 1.51;
9. oil content (%) 3.8.
The present invention has following advantage:
1.. the present invention adopts molten spinning to produce the spandex micro staple fiber, spinning speed is higher, according to the product specification requirement, spins speed and can be controlled in 300～800m/min, it is high slightly to spin speed 200～600m/min than dry spinning spandex, spins speed 50～150m/min than wet method spandex and improves 5～6 times.
2.. the present invention adopts sea-island-type composite spun to produce the polyurethane micro staple fiber, can use heavy caliber porous spinning pack, and according to the island spinnerets in Φ 220mm plate footpath, hole count is hundreds of holes.Spin few hole silk of spandex with dry method and compare, output will improve 10～20 times.
3.. the prepared spandex micro staple fiber of the present invention, island separate back filament number 0.05～0.3dtex, than surplus the conventional fine denier spandex filament number little 10 times.
4.. the resulting polyurethane of the present invention island composite short fiber performance, can satisfy the needs of general staple fibre weaving back processing, the novel elastic textile material of exploitation polyurethane staple fibre and blended yarn thereof, and can produce elastic non-woven, enlarged the range of application in fields such as elastic polyurethane woven fabric, knitwear, imitative chamois leather, dermatine.
5. preparation method of the present invention is easy, is fit to suitability for industrialized production.
Description of drawings:
Fig. 1 is a process route chart of the present invention.
The specific embodiment:
The present invention will be helped to understand by following embodiment, but content of the present invention can not be limited.
Following embodiment technology as described in Figure 1, technological parameter is except that embodiment describes, the same summary of the invention is described.
Embodiment 1
TPU/LDPE (MI=50) spinning technique
The TPU pump is for amount 13.5g/min, 180～245 ℃ of spinning temperatures, screw speed 12rep/min, screw pressure 70kg/cm
3
The LDPE pump is for amount 9.56g/min, 150～245 ℃ of spinning temperatures, screw speed 21～22rep/min, screw pressure 52～62kg/cm
2
Spinning speed 300m/min after spinning is normal, continues to improve spinning speed and can both reel smoothly to 600m/min and 800m/min.Lousiness when spinning speed is brought up to 900m/min, occurs, so spinning speed should be controlled at below the 800m/min.
Above-mentioned 300m/min spins the undrawn yarn of speed, stretches 2 times, and fibrous fracture intensity is 1.57CN/dtex, and elongation at break is 158.6%.Stretch 3 times, fibrous fracture intensity is 1.75CN/dtex, and elongation at break is 115.3%.Stretch 5 times, fibrous fracture intensity is 1.94CN/dtex, and elongation at break is 88.5%.
In above-mentioned range of stretch, fibrous fracture intensity strengthens with draw ratio, and extension at break descends with the draw ratio increase.
Embodiment 2
TPU/LDPE (MI=50) spinning technique
The TPU pump is for amount 13.5g/min, 180～235 ℃ of spinning temperatures, screw speed 12rep/min, screw pressure 97kg/cm
3
The LDPE pump is for amount 11.5g/min, 160～235 ℃ of spinning temperatures, screw speed 29rep/min, screw pressure 60kg/cm
2
Above spinning technique stretches 3.7 times, and fibrous fracture intensity is 1.2CN/dtex, and elongation at break is 134.8%.Above undrawn yarn boundling was become for 40,000 dawn, through immersion cell (oil concentration is 8～10%), enters together and carry out room temperature tensile with two road drawing roller, tow enters crimping machine by 70 ℃ of preheating cabinets then.Crimped tow is by carrier bar drying machine laxation shaping 10 minutes under 70～75 ℃ of baking temperatures, cuts off to cutting machine.Gained fiber roll curvature is 11.8%, and crispation number is 5.2/25mm, and 100% elastic recovery rate is 99%, and 100% elastic recovery rate is 90% behind the relaxation heat setting.
Embodiment 3
TPU/LDPE (MI=38) spinning technique
The TPU pump is for amount 13g/min, 190～245 ℃ of spinning temperatures, screw speed 12～13rep/min, screw pressure 67kg/cm
3
The LDPE pump is for amount 8.5g/min, 190～275 ℃ of spinning temperatures, screw speed 29rep/min, 3.3 times of gained fiber drawns, the fine density of monofilament is 9.6dtex, fibrous fracture intensity is 2.09CN/dtex, elongation at break is 126.6%, this fiber TPU content is 60%, and fibre strength is higher, and percentage elongation is bigger.Product extracts through toluene, sea component dissolving, island filament number 0.3dtex.
Embodiment 4
TPU/LDPE (MI=38) spinning technique
The TPU pump is for amount 9.5g/min, 190～245 ℃ of spinning temperatures, screw speed 12rep/min, screw pressure 58kg/cm
3
The LDPE pump is for amount 11.9g/min, 190～275 ℃ of spinning temperatures, screw speed 28rep/min, screw pressure 46kg/cm
2Above-mentioned undrawn yarn stretches 2.74 times, and fibrous fracture intensity is 0.67CN/dtex, and elongation at break is 143%, and this fiber TPU content is 45%, can spinning, but the finished silk fracture strength is on the low side.
Claims (10)
1, a kind of micro-polyurethane short fiber is that low density polyethylene (LDPE) is the component in sea, the fabric of island-in-sea type staple fibre of component that polyurethane is the island, and polyurethane and low density polyethylene (LDPE) weight ratio are 1: 0.4～1.5, and it is 0.05～0.3dtex that back filament number is separated on its island.
2, micro-polyurethane short fiber as claimed in claim 1 is characterized in that the fine density of monofilament is 6.0～10.0dtex, and fibrous fracture intensity is 1.9～2.1CN/dtex, and elongation at break is 100～160%.
3, a kind of manufacture method of micro-polyurethane short fiber as claimed in claim 1 or 2, it is characterized in that adopting twin-screw sea-island-type composite spun method, with the polyurethane of fusion through the fabric of island-in-sea type spinning plate become the multiply thread the low density polyethylene (LDPE) that the spinneret orifice porch is melted wrap up respectively, extrude tow through cool off, oil, draw-off godet, coiling, boundling after immersion cell, stretch, curl, relaxation heat setting and cut-out, wherein polyurethane and low density polyethylene (LDPE) weight ratio 1: 0.4～1.5.
4, manufacture method as claimed in claim 3 is characterized in that in the described spinning that the screw pressure of fusion polyurethane is 60～100kg/cm
2, rotating speed 10～20rep/min, spinning temperature are 180～245 ℃; It is 40～60kg/cm that the screw rod of fusion low density polyethylene (LDPE) is pressed
2, rotating speed is 20～30rep/min, spinning temperature is 170～275 ℃.Spinning speed 300～800m/min.
5, manufacture method as claimed in claim 3 is characterized in that in the described coiling, draw-off godet speed 300～800m/min, and upper oil-pan rotating speed 18～20rep/min, finish are the aqueous solution of 12～15% spandex oil agents, winding speed 300～800m/min.
6, manufacture method as claimed in claim 3 is characterized in that described boundling, and its dawn number was 4～4.5 ten thousand dawn, and the immersion cell oil concentration is the aqueous solution of the spandex oil agent of 8～10% weight.
7, manufacture method as claimed in claim 3 is characterized in that described stretching is to carry out in air dielectric, the first drawing roller speed 20m/min, the second drawing roller speed, 60～90m/min, 3～4 times of drafting multiples.
8, manufacture method as claimed in claim 3 is characterized in that described curling, through 65～70 ℃ of preheatings, and crimping machine speed 64m/min, room temperature cooling.
9, manufacture method as claimed in claim 3 is characterized in that described relaxation heat setting at 70～75 ℃, carries out the 10min typing.
10, manufacture method as claimed in claim 3 is characterized in that described cut-out, and cutting machine speed is 25m/min, and shearing length is 38～64mm.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200510023908 CN1287016C (en) | 2005-02-07 | 2005-02-07 | Micro-polyurethane short fiber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 200510023908 CN1287016C (en) | 2005-02-07 | 2005-02-07 | Micro-polyurethane short fiber |
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|---|---|
| CN1664188A true CN1664188A (en) | 2005-09-07 |
| CN1287016C CN1287016C (en) | 2006-11-29 |
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| CN 200510023908 Expired - Fee Related CN1287016C (en) | 2005-02-07 | 2005-02-07 | Micro-polyurethane short fiber |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102021673A (en) * | 2010-12-10 | 2011-04-20 | 太仓市金祥氨纶纤维有限公司 | Method for producing melt direct spinning superfine (4.6-5.5) denier high elastic modulus polyurethane fibers |
| CN102080277A (en) * | 2010-12-09 | 2011-06-01 | 武汉纺织大学 | Compound elastic fiber and preparation method thereof |
| CN105063793A (en) * | 2015-08-07 | 2015-11-18 | 无锡双象超纤材料股份有限公司 | Super-fine denier flame-retardant polyurethane short fiber and preparation method thereof |
| CN110331467A (en) * | 2019-06-24 | 2019-10-15 | 郑州中远氨纶工程技术有限公司 | A kind of super fine denier spandex and preparation method thereof to interweave with terylene |
| CN112695410A (en) * | 2020-12-16 | 2021-04-23 | 浙江华峰合成树脂有限公司 | Island-fixed type sea-island fiber and preparation method and application thereof |
-
2005
- 2005-02-07 CN CN 200510023908 patent/CN1287016C/en not_active Expired - Fee Related
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102080277A (en) * | 2010-12-09 | 2011-06-01 | 武汉纺织大学 | Compound elastic fiber and preparation method thereof |
| CN102080277B (en) * | 2010-12-09 | 2013-09-04 | 武汉纺织大学 | Compound elastic fiber and preparation method thereof |
| CN102021673A (en) * | 2010-12-10 | 2011-04-20 | 太仓市金祥氨纶纤维有限公司 | Method for producing melt direct spinning superfine (4.6-5.5) denier high elastic modulus polyurethane fibers |
| CN105063793A (en) * | 2015-08-07 | 2015-11-18 | 无锡双象超纤材料股份有限公司 | Super-fine denier flame-retardant polyurethane short fiber and preparation method thereof |
| CN110331467A (en) * | 2019-06-24 | 2019-10-15 | 郑州中远氨纶工程技术有限公司 | A kind of super fine denier spandex and preparation method thereof to interweave with terylene |
| CN110331467B (en) * | 2019-06-24 | 2021-10-26 | 郑州中远氨纶工程技术有限公司 | Superfine denier spandex interwoven with terylene and preparation method thereof |
| CN112695410A (en) * | 2020-12-16 | 2021-04-23 | 浙江华峰合成树脂有限公司 | Island-fixed type sea-island fiber and preparation method and application thereof |
| CN112695410B (en) * | 2020-12-16 | 2023-05-23 | 浙江华峰合成树脂有限公司 | Fixed island type sea-island fiber, and preparation method and application thereof |
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| CN1287016C (en) | 2006-11-29 |
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