A spinneret suitable for elastomeric materials and its use in the production of elastomeric fibers

Abstract

The present application relates to a kind of spinneret suitable for elastomer material and its application in the preparation of elastic fiber, spinneret channel from top to bottom includes smooth transition guide hole, spinneret hole and spinneret hole outlet, guide hole is composed of smooth transition guide hole channel and elastic property weakening area, guide hole channel is hollow cylinder with solid cylindrical filler in center, elastic property weakening area is hollow circular platform shape with upper large and lower small, spinneret hole is hollow cylinder, guide hole channel, elastic property weakening area and spinneret hole whole longitudinal section presents Y type;Application is: using the above-mentioned spinneret to melt spinning and obtaining elastic fiber;Wherein, spinning speed is 2000-4000 m / min.The present application reduces the melt rupture and relieves the phenomenon of off-die expansion of high-elastic polymer when melt spinning, and the spinning speed is high when applied in the preparation of elastic fiber.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of elastic fiber preparation, and relates to a spinneret suitable for elastomer material and application thereof in preparation of elastic fiber, in particular to a spinneret suitable for thermoplastic elastomer material and application thereof in preparation of elastic fiber. BACKGROUND

[0002] Elastomer materials are divided into thermosetting elastomers and thermoplastic elastomers (TPE), wherein TPE includes styrene (TPS), olefin (TPO), polyurethane (TPU) and the like, and is often used as elastomer particles in plastic modification, playing an important role in toughening and improving the impact resistance of plastics. Due to its excellent flexibility and resilience, elastomer materials are widely used in the fields of automobiles, wearable electronics, medical treatment and clothing, and can also be used in fiber applications. Common elastic fibers on the market mainly include polyolefin elastic fibers, polyurethane fibers (referred to as spandex), polyether ester elastic fibers and composite elastic fibers (T400) and the like. Spandex has high resilience characteristics, and the elastic recovery rate can reach 90%. In order to meet product demand, more and more textiles are added with appropriate spandex fibers, so that the clothes are comfortable, soft, elastic and shape-retaining. However, with the continuous expansion of demand for textiles, defects such as poor color fastness and yellowing of spandex fabrics are exposed, affecting the use of spandex in textiles. In recent years, new polyester elastic fibers such as polytrimethylene terephthalate fiber (PTT fiber), polybutylene terephthalate fiber (PBT fiber) and PET parallel composite spinning fiber (SSY elastic fiber) and other composite elastic fibers have been continuously introduced and popularized.

[0003] Although the market application of elastic fibers is continuously expanding, however, the spinning of elastomers has always been difficult. The design of the spinneret plays a crucial role in the spinning and forming process of the fiber. In the spinning duct, the viscous flow state of the polymer melt or solution is converted into a fine stream with a specific cross-sectional shape after passing through the micro-holes of the spinneret, and then cooled or crystallized and solidified in the coagulation medium (such as air or coagulation bath) to form a yarn. High polymers are usually non-Newtonian fluids, which are prone to shear thinning under the high shear action of the spinning duct. For high-elasticity polymers, the polymer will swell when it leaves the spinneret due to the elastic recovery phenomenon, which will cause the melt to break when the elastic deformation of the unit volume of the melt storage exceeds a certain threshold, thereby seriously affecting the flow stability of the melt and the spinning stability.

[0004] For high-elasticity melts, the swelling of the melt when it leaves the spinneret is an inevitable phenomenon under the existing spinning process conditions, and the spinning speed is usually not high.

[0005] For example, patent CN202111198706.X reports a kind of degradable melt spinning polyurethane elastic fiber. The patent uses diisocyanate and polyol chain extension to prepare a kind of melt-spinnable polyurethane elastic material, and the melt spinning speed is only 500-900 m / min. The reason should be that the high-elasticity polyurethane expands in the spinning process, and the high spinning speed and the microphase separation structure of spandex affect the spinning process. Patent CN201710581551.5 (polyolefin elastic fiber) discloses a melt spinning preparation method of polypropylene-based polymer monofilament. Due to the high elasticity, the spinning speed is less than 650 m / min. In addition, other spinning processes can also be adjusted, such as increasing the diameter of the jet control, reducing the metering pump rate, increasing the extrusion temperature, and increasing the jet plate length-diameter ratio to improve the spinning process of high-elasticity melt. However, the improvement of the above-mentioned scheme is limited, and the spinning efficiency and fiber quality are greatly reduced. For example, increasing the diameter of the jet hole will limit the production of fine elastic yarn.

[0006] There are also some innovative technologies that adjust the chemical structure of fiber polymer macromolecules to control the melt strength.

[0007] For example, patent CN201880011321.8 describes a high-speed preparation method of thermoplastic polyurethane elastomer. By using polyether polyol as a long-chain polyol, the spinning speed can be increased to more than 2000 m / min. The improvement scheme of this technology is mainly to change the content ratio of hard segment in the fiber matrix, and to weaken the orifice expansion phenomenon by moderately reducing the elastic shrinkage of the polymer. However, the strength of the prepared fiber is greatly affected. Patent CN201911076247 proposes a preparation method of semi-aromatic polyether amide elastomer fiber. It overcomes the complex technology of existing technology that most elastic fibers use parallel composite spinning process. The rigid benzene ring structure contained in the macromolecular chain is used as an elastic recovery point to maintain the elastic recovery ability while maintaining good thermal stability. However, due to the molecular entanglement and flowability of the polymer, the spinning speed during fiber preparation is less than 2000 m / min.

[0008] Based on the above status, although the existing technology provides various solutions based on different elastic polymers, there is still a lack of method that can effectively alleviate the orifice expansion phenomenon, greatly improve the spinning efficiency of elastomer, and obtain an elastic fiber with good performance. SUMMARY

[0009] The purpose of the present application is to solve the above-mentioned problems existing in the prior art, and to provide a jet plate suitable for elastomer material and its application in preparing elastic fiber.

[0010] To achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows:

[0011] A spinneret suitable for melt spinning of elastomer material, the spinneret channel comprises a smooth transition guide hole, a spinneret hole and a spinneret hole outlet from top to bottom, the guide hole is composed of a smooth transition guide hole channel and an elastic property weakening zone, the guide hole channel is a hollow cylinder with a solid cylindrical filler in the center, the elastic property weakening zone is a hollow circular truncated cone with a large upper part and a small lower part, the spinneret hole is a hollow cylinder, the overall longitudinal section of the guide hole channel, the elastic property weakening zone and the spinneret hole is Y-shaped.

[0012] During the flow process of the high polymer melt, the polymer (especially the elastic material) has elastic deformation and stress in the channel, if the polymer stays in the channel for a short time, the polymer chain segment cannot relax, the stress is large, and the stress is released after the mold is removed, thereby causing extrusion swelling. The structure of the spinneret is modified, the traditional columnar spinneret hole is abandoned, the feeding through hole of the spinneret is in the form of double-channel split and convergence, the stress in the normal component is offset through the intersection of the double channels, and thus the normal stress of the polymer can be reduced. By reducing the normal stress of the high polymer melt at the intersection, the elastic property of the polymer is reduced, and thus the swelling effect at the spinneret hole is reduced.

[0013] As a preferred technical solution:

[0014] The spinneret suitable for melt spinning of the elastomer material, the spinneret hole outlet is a hollow circular truncated cone with a small upper part and a large lower part, the included angle of the spinneret hole outlet is 60-120°, and the included angle of the spinneret hole outlet refers to the sum of the included angles between the two inclined edges of the spinneret hole outlet section and the vertical line.

[0015] The high polymer melt has elastic deformation in the spinneret hole, and extrusion swelling occurs after leaving the spinneret hole, when the elastic deformation is too large, the melt is broken and cannot be spun. In view of the problem that the mold swelling of the polymer (especially the elastic material) leads to melt rupture of the polymer and affects the normal processing of the fiber, the angle of the spinneret hole outlet is modified, the spinneret hole outlet is designed to have a certain angle structure, the polymer obtains a large space at the spinneret hole outlet, the high polymer melt with elastic deformation can be elastically released once, and in the elastic release process, the polymer melt extrudes the spinneret plate surface, the elasticity of the high polymer melt in the extrusion direction can be reduced, the elastic property of the polymer is reduced, the mold swelling phenomenon is reduced, and the melt rupture is prevented.

[0016] The spinneret suitable for melt spinning of the elastomer material, the length (referring to the height of the spinneret channel in the vertical direction) of the spinneret channel is 20-80 mm.

[0017] The spinneret suitable for melt spinning of the elastomer material, the length-diameter ratio of the spinneret hole is 2-9. 2-9.

[0018] The spinneret for melt spinning of elastomer material as claimed in any one of the preceding claims, preferably, the length h1 of the guide hole channel is 16 mm, the length h2 of the elastic weakening zone is 6 mm, the length h3 of the spinneret hole is 3 mm, the spinneret hole diameter is 0.6 mm, the length-diameter ratio is 5, and the length h4 of the spinneret hole outlet is 8 mm.

[0019] The spinneret for melt spinning of elastomer material as claimed in any one of the preceding claims, the spinneret is a ring spinneret, the outer diameter of the ring body of the spinneret is 40-160 mm; a central positioning through hole is arranged at the center of the spinneret, and the diameter of the central positioning through hole is 10-20 mm.

[0020] The spinneret for melt spinning of elastomer material as claimed in any one of the preceding claims, all the spinneret holes and the guide holes are uniformly distributed on the spinneret in concentric circles.

[0021] The spinneret for melt spinning of elastomer material as claimed in any one of the preceding claims, the elastomer material is polystyrene block copolymer, polyurethane soft and hard segment elastomer, polyether ester soft and hard segment copolyester, polyester soft and hard segment copolyester or binary copolyester, and the elastomer material includes but is not limited to the above-mentioned types.

[0022] The spinneret for melt spinning of elastomer material as claimed in any one of the preceding claims, the elastomer material is polyethylene glycol ether-polybutylene terephthalate copolyester (PEG-PBT), polybutylene adipate terephthalate (PBAT), polybutylene succinate (PBS), polybutylene terephthalate (PBT) or polytrimethylene terephthalate (PTT).

[0023] The present application further provides a preparation method of elastic fiber, which uses the spinneret as claimed in any one of the preceding claims to melt spin the elastic fiber from an elastomer material.

[0024] The spinning speed is 2000-4000 m / min.

[0025] When the elastomer material is polyethylene glycol ether-polybutylene terephthalate copolyester, the strength of the prepared elastic fiber is 1.5-2.4 cN / dtex.

[0026] When the elastomer material is polybutylene adipate terephthalate, the breaking strength of the prepared elastic fiber is 1.8-2.6 cN / dtex.

[0027] When the elastomer material is polybutylene succinate, the breaking strength of the prepared elastic fiber is 1.7-2.5 cN / dtex.

[0028] ​​​When the elastic material is polybutylene terephthalate, the breaking strength of the elastic fiber prepared is 2.3-2.9 cN / dtex.

[0029] When the elastic material is polybutylene terephthalate, the breaking strength of the elastic fiber prepared is 2.3-2.9 cN / dtex.

[0030] When the shear rate or shear stress exceeds a certain critical value in the extrusion process of the polymer melt, the appearance of the extrudate changes from smooth to rough, bamboo-shaped, or even fragmented, which is the melt fracture phenomenon. When the elastic property of the polymer is too large, the extrusion swell phenomenon is obvious, and at this time, the spinning speed of the polymer cannot be too fast, otherwise the melt fracture will occur, and even the continuous fiber cannot be obtained. When the melt spinning plate designed in the application is used to prepare polymer fibers, especially elastic fibers, the orifice swell phenomenon can be effectively alleviated, the problem of poor spinnability of high-elasticity materials in the prior art can be solved, and the spinning speed can be increased without affecting or even improving the fiber performance.

[0031] Advantages:

[0032] (1) The spinning duct of the spinning plate of the application is simple to form and is suitable for melt spinning of elastomer materials;

[0033] (2) The feeding through hole of the spinning plate of the application adopts a double-duct split-flow converging form, which weakens the melt elasticity of the melt in the spinning plate, and at the same time, a large included angle is adopted at the discharge port of the spinning plate to release the melt spewing elasticity, thereby weakening the melt fracture and relieving the demolding swelling phenomenon of high-elasticity polymers during melt spinning;

[0034] (3) When the spinning plate of the application is used for melt spinning to prepare elastic fibers, the production speed can reach 4000 m / min. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 It is an exploded view of the spinning plate assembly of the application;

[0036] Figure 2 It is a cross-sectional schematic view of a spinning plate duct of the application;

[0037] Figure 3 It is a cross-sectional schematic view of another spinning plate duct of the application;

[0038] Figure 4 It is a schematic view of the whole spinning plate of the application;

[0039] Among them, 1 is a cover plate, 2 is a distribution plate, 3 is a melt split modification component, 4 is a spinning plate, 5 is a bottom plate, 6 is a guide hole channel, 7 is an elastic property weakening zone, 8 is a spinning hole, and 9 is a spinning hole outlet. DETAILED DESCRIPTION

[0040] The present invention will be further described below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0041] A spinneret suitable for melt spinning of elastomer materials, wherein the spinneret channel includes, from top to bottom, smoothly transitioning guide holes, spinneret holes, and spinneret hole outlets. The guide holes consist of smoothly transitioning guide hole channels and elastic energy weakening zones. The guide hole channels are hollow cylinders with a solid cylindrical filler (i.e., melt flow diversion modification components) in the center. The elastic energy weakening zones are hollow frustum-shaped, larger at the top and smaller at the bottom. The spinneret holes are hollow cylinders. The overall longitudinal section of the guide hole channels, elastic energy weakening zones, and spinneret holes is Y-shaped. Preferably, the spinneret hole outlet is a hollow frustum-shaped, smaller at the top and larger at the bottom, and the included angle of the spinneret hole outlet is 60-120°.

[0042] The spinneret is the main body of the spinneret assembly, such as... Figure 1 As shown, in this invention, the spinneret assembly consists of a cover plate 1, a distribution plate 2, a melt diversion modification component 3, a spinneret 4, and a base plate 5. The melt diversion modification component 3 is located at the bottom end of the distribution plate 2 and is positioned and embedded by the distribution plate 2 and the spinneret 4, thereby forming a guide channel.

[0043] The length of the spinneret channel is 20–80 mm, and the length-to-diameter ratio of the spinneret orifice is... The values ​​are 2 to 9. Preferably, the length h1 of the guide channel is 16 mm, the length h2 of the elastic energy weakening zone is 6 mm, the length h3 of the spinneret orifice is 3 mm, and the spinneret orifice diameter is... The diameter is 0.6 mm, and the length h4 of the spinneret outlet is 8 mm;

[0044] like Figure 4 As shown, the spinneret is an annular spinneret, and the outer diameter of the annular spinneret is... The diameter is 40-160mm; a central positioning through hole is provided at the center of the spinneret, and the diameter of the central positioning through hole is... The diameter is 10-20 mm; all spinneret holes and guide holes are evenly distributed in concentric circles on the spinneret plate.

[0045] Example 1

[0046] A spinneret suitable for melt spinning of elastomer materials, such as Figure 2As shown, the spinneret channel includes a smoothly transitioning guide hole, a spinneret hole 8, and a spinneret hole outlet from top to bottom. The guide hole consists of a smoothly transitioning guide hole channel 6 and an elastic energy weakening zone 7. The guide hole channel 6 is a hollow cylinder with a solid cylindrical filler (i.e., a melt flow reduction modification component) in the center. The elastic energy weakening zone 7 is a hollow frustum shape that is larger at the top and smaller at the bottom. The spinneret hole 8 is a hollow cylinder. The overall longitudinal section of the guide hole channel 6, the elastic energy weakening zone 7, and the spinneret hole 8 is Y-shaped.

[0047] The length h1 of the guide channel is 16 mm, the length h2 of the elastic energy weakening zone is 6 mm, the length h3 of the spinneret orifice is 3 mm, and the spinneret orifice diameter is... It is 0.6mm;

[0048] The spinneret is an annular spinneret, and the outer diameter of the annular body of the spinneret is... The diameter is 40mm; a central positioning through hole is provided at the center of the spinneret, and the diameter of the central positioning through hole is... The diameter is 10mm; all spinneret holes and guide holes are evenly distributed in concentric circles on the spinneret.

[0049] Example 2

[0050] A spinneret suitable for melt spinning of elastomer materials, such as Figure 3 As shown, the spinneret channel includes, from top to bottom, a smoothly transitioning guide hole, a spinneret hole 8, and a spinneret hole outlet 9. The guide hole consists of a smoothly transitioning guide hole channel 6 and an elastic energy weakening zone 7. The guide hole channel 6 is a hollow cylinder with a solid cylindrical filler (i.e., a melt flow reduction modification component) in the center. The elastic energy weakening zone 7 is a hollow frustum shaped like a cone with a larger top and a smaller bottom. The spinneret hole 8 is a hollow cylinder. The overall longitudinal section of the guide hole channel 6, the elastic energy weakening zone 7, and the spinneret hole 8 is Y-shaped. The spinneret hole outlet 9 is a hollow frustum shaped like a cone with a smaller top and a larger bottom, and the included angle of the spinneret hole outlet 9 is 60°.

[0051] The length h1 of the guide channel is 16 mm, the length h2 of the elastic energy weakening zone is 6 mm, the length h3 of the spinneret orifice is 3 mm, and the spinneret orifice diameter is... The diameter is 0.6 mm, and the length h4 of the spinneret outlet is 8 mm;

[0052] The spinneret is an annular spinneret, and the outer diameter of the annular body of the spinneret is... The diameter is 160mm; a central positioning through hole is provided at the center of the spinneret, and the diameter of the central positioning through hole is... The diameter is 20mm; all spinneret holes and guide holes are evenly distributed in concentric circles on the spinneret.

[0053] Example 3

[0054] A method for preparing elastic fibers, the specific steps of which are as follows:

[0055] (1) Preparation of raw materials;

[0056] The elastic material is polyethylene glycol ether-polybutylene terephthalate copolyester (brand name: Dow-TPU 2103-70A, USA).

[0057] (2) The elastic fiber is prepared by melt spinning using the spinneret described in Example 1; wherein the spinning temperature is 210℃, and the spinning speed is 2000 m / min.

[0058] The breaking strength of the prepared elastic fiber is 2.0 cN / dtex.

[0059] Example 4

[0060] A method for preparing an elastic fiber, the specific steps are as follows:

[0061] (1) Preparation of raw materials;

[0062] The elastic material is polybutylene terephthalate (brand name: Yizheng Sinopec-TA159) ;

[0063] (2) The elastic fiber is prepared by melt spinning using the spinneret described in Example 1; wherein the spinning temperature is 240℃, and the spinning speed is 2500 m / min.

[0064] The breaking strength of the prepared elastic fiber is 2.1 cN / dtex.

[0065] Example 5

[0066] A method for preparing an elastic fiber, the specific steps are as follows:

[0067] (1) Preparation of raw materials;

[0068] The elastic material is polybutylene succinate (brand name: Xinjiang Lanshan Tunhe-TH802A) ;

[0069] (2) The elastic fiber is prepared by melt spinning using the spinneret described in Example 2; wherein the spinning temperature is 190℃, and the spinning speed is 3000 m / min.

[0070] The breaking strength of the prepared elastic fiber is 2.3 cN / dtex.

[0071] Example 6

[0072] A method for preparing an elastic fiber, the specific steps are as follows:

[0073] (1) Preparation of raw materials;

[0074] The elastic material is polybutylene terephthalate (brand name: Kanghui New Material Technology Co., Ltd.-KH2080) ;

[0075] (2) melt spinning to obtain elastic fiber using the spinneret described in Example 2; wherein the spinning temperature is 270°C and the spinning speed is 3500 m / min.

[0076] The breaking strength of the obtained elastic fiber is 2.9 cN / dtex.

[0077] Example 7

[0078] A method for preparing an elastic fiber, the specific steps are as follows:

[0079] (1) preparation of raw materials;

[0080] The elastic material is: polytrimethylene terephthalate (trade name: DuPont-2285, USA);

[0081] (2) melt spinning to obtain elastic fiber using the spinneret described in Example 2; wherein the spinning temperature is 260°C and the spinning speed is 4000 m / min.

[0082] The breaking strength of the obtained elastic fiber is 2.7 cN / dtex.

Claims

1. A process for the preparation of spandex characterized by: The elastic fiber is prepared by using an elastic material as raw material and adopting a spinneret for melt spinning; The spinneret channel comprises a smooth transition guide hole, a spinneret hole and a spinneret hole outlet from top to bottom, the guide hole is composed of a smooth transition guide hole channel and an elastic property weakening area, the guide hole channel is a hollow cylinder with a solid cylindrical filler in the center, the elastic property weakening area is a hollow circular truncated cone with a large upper part and a small lower part, the spinneret hole is a hollow cylinder, the longitudinal section of the guide hole channel, the elastic property weakening area and the spinneret hole is Y-shaped as a whole; The solid cylindrical filler is located at the bottom end of the distribution plate and is embedded by the distribution plate and the spinneret plate, thereby forming the guide hole channel; the double-channel shunt confluence form is adopted, the stress in the normal force component is offset through the double-channel intersection, and thus the normal stress of the polymer can be weakened; The spinning speed is 2000-4000 m / min; When the elastic material is polyethylene glycol ether-polybutylene terephthalate, the breaking strength of the prepared elastic fiber is 1.5-2.4 cN / dtex; When the elastic material is polybutylene terephthalate, the breaking strength of the prepared elastic fiber is 1.8-2.6 cN / dtex; When the elastic material is polybutylene succinate, the breaking strength of the prepared elastic fiber is 1.7-2.5 cN / dtex; When the elastic material is polybutylene terephthalate, the breaking strength of the prepared elastic fiber is 2.2-2.8 cN / dtex; When the elastic material is polybutylene terephthalate, the breaking strength of the prepared elastic fiber is 2.2-2.8 cN / dtex.

2. The process for preparing spandex according to claim 1, characterized in that, The spinneret hole outlet is a hollow circular truncated cone with a small upper part and a large lower part, and the included angle of the spinneret hole outlet is 60-120°.

3. The process for preparing spandex as claimed in claim 2, wherein The length of the spinneret channel is 20-80 mm.

4. The process for preparing spandex as claimed in claim 3, wherein The length-diameter ratio of the spinneret hole is 2-9.

5. The process for preparing spandex according to any one of claims 1 to 4, characterized in that, The spinneret is a ring spinneret, the outer diameter φ1 of the ring body of the spinneret is 40-160 mm; a center positioning through hole is arranged at the center of the spinneret, and the diameter φ2 of the center positioning through hole is 10-20 mm.

6. The process for preparing spandex as claimed in claim 5, wherein All the spinneret holes and the guide holes are uniformly distributed on the spinneret in the form of concentric circles.

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