Manufacturing process of composite fiber

Abstract

The invention discloses a manufacturing process of a composite fiber, and solves the problems that in the prior art, in the actual use process, due to different melting points, a concentric spinning nozzle cannot be adopted for skin-core type composite fibers made of PE / PP and PE / PET materials, otherwise, the fibers with low melting points are not formed and broken, and the fibers with high melting points cannot be formed. The fibers with the high melting point are sprayed out, cooled and shaped and then output from the concentric spinning nozzle together with the materials with the low melting point, so that the situation that the fibers with the low melting point are not formed and broken due to the fact that the fibers with the high melting point transfer heat to the fiber components with the low melting point is avoided, and the product quality is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of plastic fiber production, and in particular to a process for producing composite fibers. Background Art

[0002] Composite fiber is a kind of multi-component fiber, which is a term for artificial fiber varieties. There are two or more unmixed polymer fibers on the same fiber cross section. This kind of fiber is called composite fiber. It is a physically modified fiber developed in the 1960s. The composite fiber manufacturing technology can obtain two-component fibers with the characteristics of two polymers. There are parallel type, skin-core type, island type and other composite fibers, and the fiber cross section is round and special-shaped. The fiber has three-dimensional curling, high fluffiness and coverage, good conductivity, antistatic and flame retardancy. Composite fiber needs to be spun by a composite spinning machine with a special structure. It is mainly used for wool, blankets, wool fabrics, warm wadding fillings, silk fabrics, non-woven fabrics, medical and sanitary products and special work clothes.

[0003] According to the different types of polymers, components and configuration forms of the two components of composite fibers, there are hundreds of fiber varieties. According to the cross-section and longitudinal arrangement, composite fibers can be divided into skin-core type, parallel type, island type and split type.

[0004] Sheath-core composite fiber: a fiber in which two polymers continuously form the sheath and core layers along the longitudinal direction of the fiber. There are concentric and eccentric circular fibers, slightly irregular core sections, and sheath-core composite fibers with irregular sheaths and cores. Fibers with special materials as the core have special properties, such as making flame-retardant fibers with flame-retardant polymers as the core and ordinary polyester as the sheath.

[0005] Parallel composite fiber: composite fiber with two component polymers arranged on both sides of the fiber along the longitudinal direction, also known as bilateral structure type and half-moon type fiber, the two components can be equal or unequal. In order to prevent the interface peeling of the two component polymers and improve the fiber performance, the two component polymers with different properties are mostly the same type of polymers to increase the compatibility of the two component polymers at the interface.

[0006] Sea-island composite fiber: a composite fiber formed by uniformly embedding the dispersed phase polymer in the continuous phase polymer. The dispersed phase polymer is discontinuously distributed along the longitudinal direction of the fiber in the form of microfibrils, which is called matrix-microfiber type; the dispersed phase polymer is called dispersed type or lotus root core type. The two phases are composed of polymers of the same type but different properties, which is called dual-component sea-island fiber. The fiber has many unique properties, such as hygroscopicity, antistatic property, temperature and light sensitivity color change, dyeability, flame retardancy, etc.

[0007] At present, in actual use, the existing technology still has the problem that the core-sheath composite fibers of PE / PP and PE / PET materials cannot use concentric spinnerets due to their different melting points, otherwise the fibers with low melting points will not be formed or broken. Summary of the invention

[0008] Therefore, in view of the above problems, the present invention proposes a process for producing composite fibers, which solves the technical problem that the sheath-core composite fibers of PE / PP and PE / PET materials cannot be made of concentric spinnerets due to their different melting points during actual use, otherwise the fibers with low melting points will not be formed or broken.

[0009] To achieve the above object, the present invention adopts the following technical solution: a process for making a composite fiber, the steps of which include:

[0010] a. Pre-treating the particles of the two materials;

[0011] b. Two kinds of pre-treated particles are fed into different screw extruders for extrusion;

[0012] c. First, extrude the fiber of material A with a higher melting point, and use dry air to preliminarily cool the fiber to make it completely solidified. Then, pass the solidified fiber A through the inner hole of the concentric spinneret, and pass the material B with a lower melting point through the outer hole of the concentric spinneret and output synchronously with the movement of the fiber A, so that the material B is coated on the outer surface of the fiber A to form a skin-core composite fiber structure;

[0013] d. Send it into a water-cooled or air-cooled box for cooling;

[0014] e. After cooling to room temperature, send it into the heat treatment chamber for heat treatment;

[0015] f. After heat treatment, the composite fiber is sent to a cooling device for rapid cooling.

[0016] Furthermore, the pretreatment includes inputting large particles into a crusher to be crushed into small particles with a diameter not greater than 4 mm, and then sending them into a drying chamber for heating and drying, the drying temperature is 120-140 degrees Celsius, and the drying time is 8-10 hours.

[0017] Furthermore, the heating temperature of the heat treatment in step e is 170-180 degrees Celsius, and the heat treatment time is 5-10 minutes.

[0018] Furthermore, the specific process of rapid cooling in step f is as follows:

[0019] The fiber is taken out from the heat treatment chamber, sent to the air cooling chamber, and input with room temperature air mixed with atomized water for rapid cooling for 1-2 minutes, so that it is quickly cooled from 170-180 degrees Celsius in the heat treatment chamber to 80-90 degrees Celsius. After cooling to 80-90 degrees Celsius, it is taken out from the air cooling chamber by a forklift, and then placed in a light-proof, ventilated room or equipment for low wind speed air supply treatment for 10-30 minutes, and cooled to below 60 degrees Celsius. In this process, the moisture adhered in step 1 is dissipated by evaporation, and then the fiber and the container loaded with it are placed in a ventilated storage room or factory to naturally cool to room temperature.

[0020] Furthermore, the heating temperature of the heat treatment in step e is 170 degrees Celsius, and the heat treatment time is 10 minutes.

[0021] Furthermore, room temperature air mixed with atomized water is input into the air cooling chamber for rapid cooling for 1 minute, so that the temperature is quickly reduced from 170 degrees Celsius in the heat treatment chamber to 80 degrees Celsius. After cooling to 80 degrees Celsius, it is taken out of the air cooling chamber using a forklift and then placed in a light-proof, ventilated room or equipment with low wind speed air supply for 30 minutes. At this time, the fiber temperature is reduced to below 40 degrees Celsius.

[0022] By adopting the above-mentioned technical scheme, the beneficial effect of the present invention is that the production process of the composite fiber improves the existing technology. In actual use, the skin-core composite fibers of PE / PP and PE / PET materials still cannot use concentric spinnerets due to their different melting points, otherwise the fibers with low melting points will be deformed or broken. By first spraying out the fibers with high melting points, cooling and shaping them, and then outputting them from the concentric spinneret at the same time as the materials with low melting points, it is avoided that the fibers with high melting points transfer heat to the fiber components with low melting points, causing the fibers with low melting points to be deformed or broken, thereby ensuring product quality. DETAILED DESCRIPTION

[0023] The present invention will now be further described in conjunction with specific implementation methods.

[0024] This embodiment provides a process for manufacturing a composite fiber, the steps of which include:

[0025] a. Pre-treating the particles of the two materials;

[0026] b. Two kinds of pre-treated particles are fed into different screw extruders for extrusion;

[0027] c. First, extrude the fiber of material A with a higher melting point, and use dry air to preliminarily cool the fiber to make it completely solidified. Then, pass the solidified fiber A through the inner hole of the concentric spinneret, and pass the material B with a lower melting point through the outer hole of the concentric spinneret and output synchronously with the movement of the fiber A, so that the material B is coated on the outer surface of the fiber A to form a skin-core composite fiber structure;

[0028] d. Send it into a water-cooled or air-cooled box for cooling;

[0029] e. After cooling to room temperature, send it into the heat treatment chamber for heat treatment;

[0030] f. After heat treatment, the composite fiber is sent to a cooling device for rapid cooling.

[0031] The pretreatment includes inputting large particles into a crusher to be crushed into small particles with a diameter not greater than 4 mm, and then sending them into a drying chamber for heating and drying. The drying temperature is 120-140 degrees Celsius and the drying time is 8-10 hours.

[0032] The heating temperature of the heat treatment in step e is 170-180 degrees Celsius, and the heat treatment time is 5-10 minutes.

[0033] The specific process of rapid cooling in step f is as follows:

[0034] The fiber is taken out of the heat treatment chamber and sent into the air cooling chamber to be rapidly cooled for 1-2 minutes by inputting normal temperature air mixed with atomized water, so that the fiber is rapidly cooled from 170-180 degrees Celsius in the heat treatment chamber to 80-90 degrees Celsius;

[0035] After cooling to 80-90 degrees Celsius, take it out of the air-cooling room with a forklift, and then place it in a light-proof, ventilated room or equipment with low wind speed for 10-30 minutes, and cool it to below 60 degrees Celsius. In this process, the moisture adhered in step 1 is dissipated by evaporation;

[0036] The fibers and their containers are then placed in a ventilated storage room or workshop to cool naturally to room temperature.

[0037] Embodiment 2

[0038] The heating temperature of the heat treatment in step e is 170 degrees Celsius, and the heat treatment time is 10 minutes.

[0039] Normal temperature air mixed with atomized water is input into the air cooling chamber for rapid cooling for 1 minute, so that the temperature is rapidly reduced from 170 degrees Celsius in the heat treatment chamber to 80 degrees Celsius;

[0040] After cooling to 80 degrees Celsius, take it out of the air-cooling room with a forklift, and then place it in a light-proof, ventilated room or equipment with low wind speed for 30 minutes. At this time, the fiber temperature drops to below 40 degrees Celsius.

[0041] The production process of the composite fiber improves the existing technology. In actual use, the core-sheath composite fibers of PE / PP and PE / PET materials cannot use concentric spinnerets due to their different melting points. Otherwise, the fibers with low melting points will not be formed or broken. By first spraying out the fibers with high melting points, cooling and shaping them, and then outputting them from the concentric spinneret at the same time as the materials with low melting points, it is avoided that the fibers with high melting points transfer heat to the fiber components with low melting points, causing the fibers with low melting points to be not formed or broken, thereby ensuring product quality.

[0042] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the attached claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any mark in the claims should not be regarded as limiting the claims involved.

[0043] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A process for producing a composite fiber, characterized in that: The steps include: a. Pre-treating the particles of the two materials; b. Two kinds of pre-treated particles are fed into different screw extruders for extrusion; c. First, extrude the fiber of material A with a higher melting point, and use dry air to preliminarily cool the fiber to make it completely solidified. Then, pass the solidified fiber A through the inner hole of the concentric spinneret, and pass the material B with a lower melting point through the outer hole of the concentric spinneret and output synchronously with the movement of the fiber A, so that the material B is coated on the outer surface of the fiber A to form a skin-core composite fiber structure; d. Send it into a water-cooled or air-cooled box for cooling; e. After cooling to room temperature, send it into the heat treatment chamber for heat treatment; f. After heat treatment, the composite fiber is sent to a cooling device for rapid cooling.

2. A process for producing a composite fiber according to claim 1, characterized in that: The pretreatment includes inputting large particles into a crusher to be crushed into small particles with a diameter not greater than 4 mm, and then sending them into a drying chamber for heating and drying. The drying temperature is 120-140 degrees Celsius and the drying time is 8-10 hours.

3. The process for producing a composite fiber according to claim 1, characterized in that: The heating temperature of the heat treatment in step e is 170-180 degrees Celsius, and the heat treatment time is 5-10 minutes.

4. The process for producing a composite fiber according to claim 1, characterized in that: The specific process of rapid cooling in step f is as follows: The fiber is taken out of the heat treatment chamber and sent into the air cooling chamber to be rapidly cooled for 1-2 minutes by inputting normal temperature air mixed with atomized water, so that the fiber is rapidly cooled from 170-180 degrees Celsius in the heat treatment chamber to 80-90 degrees Celsius; After cooling to 80-90 degrees Celsius, take it out of the air-cooling room with a forklift, and then place it in a light-proof, ventilated room or equipment with low wind speed for 10-30 minutes, and cool it to below 60 degrees Celsius. In this process, the moisture adhered in step 1 is dissipated by evaporation; The fibers and their containers are then placed in a ventilated storage room or workshop to cool naturally to room temperature.

5. The process for producing a composite fiber according to claim 3, characterized in that: The heating temperature of the heat treatment in step e is 170 degrees Celsius, and the heat treatment time is 10 minutes.

6. The process for producing a composite fiber according to claim 4, characterized in that: Normal temperature air mixed with atomized water is input into the air cooling chamber for rapid cooling for 1 minute, so that the temperature is rapidly reduced from 170 degrees Celsius in the heat treatment chamber to 80 degrees Celsius; After cooling to 80 degrees Celsius, take it out of the air-cooling room with a forklift, and then place it in a light-proof, ventilated room or equipment with low wind speed for 30 minutes. At this time, the fiber temperature drops to below 40 degrees Celsius.