Green polyester sea-island fiber as well as preparation method and application thereof

Abstract

The invention discloses a green polyester sea-island fiber and a preparation method and application thereof, and the method comprises the following steps: 1) performing vacuum drying on an island component raw material and a sea component raw material, respectively melting the island component raw material and the sea component raw material by a screw, quantitatively conveying the melted island component raw material and sea component raw material into a spinning manifold through a metering pump, and further uniformly distributing the melted island component raw material and sea component raw material into a sea-island composite spinning device in the spinning manifold; and 2) synchronously injecting the island component and the sea component into a spinneret plate in a sea-island composite spinning device, compounding, spraying fiber monofilaments with a sea-island structure, carrying out air blowing cooling, oiling and winding treatment to obtain protofilaments, and carrying out drafting treatment to obtain the green polyester sea-island fiber. According to the scheme, the green polyester and the water-soluble polyester which are prepared through catalysis of the titanium catalyst serve as a sea component and an island component respectively, the problem of environmental pollution existing in post-treatment processes such as splitting and dyeing can be effectively solved, and after splitting treatment, the green polyester and the water-soluble polyester can serve as superfine fibers to be applied to the fields of artificial leather, high-water-absorption fabric, cleaning cloth and the like.

Description

Technical Field

[0001] The invention relates to a sea-island structure fiber, in particular to a green polyester sea-island fiber and a preparation method and application thereof, belonging to the technical field of textile materials. Background Art

[0002] Sea-island fibers are differentiated fibers created by evenly dispersing one polymer within another and spinning it. Within the fiber cross-section, the dispersed phase appears as "islands," while the matrix acts as the "sea." The sea phase can generally be removed, leaving behind an island phase with very low fineness. Polyester, the largest-volume chemical fiber raw material in China, has been industrialized for the production of sea-island fibers. The resulting microfibers are widely used in imitation leather fabrics, high-end fabrics, and filter membranes, and numerous related research and patents have been reported.

[0003] However, traditional island-in-the-sea fibers may contain heavy metal catalysts (such as antimony catalysts) or flame retardants (such as brominated compounds), which pose certain environmental toxicity risks. Using bio-based / degradable alternatives to island-in-the-sea fiber production can avoid pollution, but it will increase overall costs by at least two times, making it less economical. Therefore, it is necessary to develop a green polyester island-in-the-sea fiber, its preparation method, and its application to overcome these problems. Summary of the Invention

[0004] The purpose of the present invention is to solve the above problems and provide a green polyester sea island fiber and its preparation method and application to solve environmental pollution and cost problems and improve environmental protection performance.

[0005] The technical solution of the present invention is: a green polyester sea-island fiber, including an island component and a sea component, characterized in that: the island component is titanium-based polyethylene terephthalate (Ti-PET), and the island component contains a compatibilizer and a biochar enhancer. The compatibilizer can improve the interfacial compatibility between the island component and the sea component and reduce phase separation defects. The biochar enhancer can adsorb heavy metals or pollutants, giving the fiber environmental remediation potential (such as filter material); the sea component is titanium-based water-soluble polyester (Ti-COPET), and the titanium-based water-soluble polyester (Ti-COPET) can be removed by hot alkali solution, with the dual advantages of easy industrialization and environmental protection; the linear density of the green polyester sea-island fiber is 60-100 dtex, the breaking strength is 2.5-3.5 cN / dtex, and the elongation at break is 20-40%.

[0006] Specifically, the preparation method of the island component is as follows: titanium-based polyethylene terephthalate (Ti-PET) is prepared by a titanium-based catalyst (for example, tetrabutyl titanate), the addition amount of the biochar enhancer is 3 to 10 wt% of the island component, and the addition amount of the compatibilizer is 1 to 3 wt% of the island component. The titanium-based polyethylene terephthalate (Ti-PET) chips (vacuum dried at 80°C for 6 hours) and the compatibilizer and biochar enhancer (dried at 120°C for 4 hours) are mixed at high speed and then melt-extruded through a twin-screw extruder. After the extruded strips are cooled, they are pelletized.

[0007] Specifically, the preparation method of the sea component is as follows: titanium-based water-soluble polyester (Ti-COPET) is prepared using a titanium-based catalyst (for example, tetrabutyl titanate), and the titanium-based water-soluble polyester (Ti-COPET) slices are dried to a water content of less than 100 ppm.

[0008] The present invention also provides a method for preparing green polyester sea-island fibers, comprising the following steps:

[0009] Step (1) After the island component and sea component raw materials are vacuum dried, they are melted by screws to indirectly reduce carbon emissions, and then quantitatively transported into the spinning manifold by a metering pump, and further evenly distributed into the sea-island composite spinning device in the spinning manifold.

[0010] In step (2), the island component and the sea component are simultaneously injected into the spinneret inside the island-in-the-sea composite spinning device. After composite, several fiber monofilaments with an island-in-the-sea structure are ejected. After air-cooling treatment, oiling treatment and winding treatment, the raw yarn is obtained, and then the green polyester island fiber is obtained by drawing treatment.

[0011] Furthermore, the preparation method of the above-mentioned green polyester sea island fiber, wherein: in the step (1), the proportion of the island component and the sea component is accurately controlled by a metering pump, and the unmelted particles are removed by a 100-200 mesh sieve, the pump supply of the island component is 40-50 g / min, and the metering pump speed is 25-30 r / min; the pump supply of the sea component is 20-30 g / min, and the metering pump speed is 25-30 r / min.

[0012] Furthermore, in the above-mentioned method for preparing green polyester sea-island fibers, in the step (ii), the spinning temperature of the sea-island composite spinning device is 285-290°C.

[0013] Furthermore, the preparation method of the above-mentioned green polyester sea island fiber, wherein: in the step (2), the blowing cooling treatment adopts a side blowing method with a wind speed of 0.3 to 0.8 m / s, a side blowing temperature of 10 to 18°C, a side blowing humidity of 60 to 70%, and a side blowing pressure of 100 to 200 Pa.

[0014] Furthermore, in the method for preparing the green polyester sea-island fiber, in the step (2), the winding speed adopted in the winding process is 2500 to 3500 m / min.

[0015] Furthermore, in the preparation method of the above-mentioned green polyester sea island fiber, in which: in the step (2), the raw yarn drawing treatment adopts hot roller-hot plate drawing, the drawing ratio is 1.5 to 3.5, and the drawing speed is 100 to 150 m / min.

[0016] Compared with the existing technology, the present invention uses green polyester and water-soluble polyester prepared by titanium-based catalysts as the sea component and island component, respectively, which can effectively reduce the environmental pollution problems existing in post-processing processes such as fiber opening and dyeing; the island component contains a compatibilizer and a biochar enhancer. The compatibilizer can improve the interfacial compatibility between the island component and the sea component and reduce phase separation defects. The biochar enhancer can adsorb heavy metals or pollutants, giving the fiber environmental repair potential.

[0017] The green polyester sea-island fibers produced by this invention have two components arranged in an island-like pattern: the island component is a green antimony-free polyester, and the sea component is a titanium-based water-soluble polyester. After post-processing such as fiber opening and dyeing, they can be widely used in applications such as imitation leather fabrics, high-end fabrics, highly absorbent fabrics, clean cloths, or filter membranes, demonstrating excellent overall environmental performance. Furthermore, the fiber production method reduces energy consumption and avoids the environmental pollution caused by the interaction of large amounts of carbon emissions with other air pollutants, thereby enhancing its green and environmentally friendly performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 Schematic cross-sectional view of the island-in-the-sea raw yarn prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0019] The technical solution of the present invention is further described below in conjunction with the accompanying drawings. In order to make the purpose, technical solution and advantages of the present invention more clear, the present invention is further described in conjunction with specific examples. However, it should not be understood that the scope of protection of the above-mentioned subject matter of the present invention is limited to the following embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0020] Example 1

[0021] Titanium-based polyethylene terephthalate (Ti-PET) with an intrinsic viscosity of 0.685 dL / g was selected as the island component, and titanium-based water-soluble polyester (Ti-COPET) with an intrinsic viscosity of 0.525 dL / g was selected as the sea component. The two were screw-melted and extruded at a mass ratio of 70:30 to produce green polyester sea-island composite spinning. The specific steps are as follows:

[0022] Step 1) Titanium-based polyethylene terephthalate (Ti-PET) chips with an intrinsic viscosity of 0.685 dL / g are vacuum dried at 130°C for 12 hours, then mixed with 1 wt% compatibilizer and 3 wt% biochar enhancer (dried at 120°C for 4 hours), and melt-extruded into pellets through a twin-screw extruder; after drying, the modified pellets are heated and melted by the spinning main screw, and accurately measured by a metering pump and transported to the spinning box body, and evenly distributed to the island-in-the-sea composite spinning device in the spinning box body.

[0023] Step 2) Titanium-based water-soluble polyester (Ti-COPET) chips with an intrinsic viscosity of 0.525 dL / g were vacuum dried at 130°C for 12 hours, heated and melted by a secondary screw, and accurately metered by a metering pump before being transported into a spinning manifold. Within the spinning manifold, the chips were evenly distributed to the island-in-the-sea composite spinning device.

[0024] Step 3) The melts of modified titanium-based polyethylene terephthalate (Ti-PET) and titanium-based water-soluble polyester (Ti-COPET) are synchronously injected into the spinneret inside the island-in-sea composite spinning device. The temperature of the composite spinning device is 288°C. After composite, several fiber monofilaments with an island structure are extruded, and cooled by side blowing and spinning tunnel, wherein the blowing cooling temperature is 11.5°C and the blowing cooling air pressure is 100Pa. Then, the monofilaments are successively subjected to a bunching and oiling treatment and a winding machine with a speed of 3000m / min to obtain a raw yarn. The raw yarn is then subjected to a drawing treatment, wherein the temperature of the hot roller is 90°C, the temperature of the hot plate is 150°C, the drawing ratio is 1.8, and the winding speed is 150m / min to obtain a green modified polyester island fiber.

[0025] See also Figure 1 The figure shows that the green polyester sea island fiber (Example 1) prepared with modified titanium-based polyethylene terephthalate as the island component and titanium-based water-soluble polyester as the sea component has a clear sea phase, and the island phase is evenly distributed and has good stability.

[0026] Example 2

[0027] Titanium-based polyethylene terephthalate (Ti-PET) with an intrinsic viscosity of 0.685 dL / g was selected as the island component, and titanium-based water-soluble polyester (Ti-COPET) with an intrinsic viscosity of 0.525 dL / g was selected as the sea component. The two were screw-melted and extruded at a mass ratio of 70:30 to produce green polyester sea-island composite spinning. The specific steps are as follows:

[0028] Step 1) Titanium-based polyethylene terephthalate (Ti-PET) chips with an intrinsic viscosity of 0.685 dL / g are vacuum dried at 130°C for 12 hours, then mixed with 1 wt% compatibilizer and 3 wt% biochar enhancer (dried at 120°C for 4 hours), heated and melted by the main screw, and accurately measured by a metering pump before being transported into the spinning manifold and evenly distributed into the island-in-the-sea composite spinning device within the spinning manifold.

[0029] Step 2) Titanium-based water-soluble polyester (Ti-COPET) chips with an intrinsic viscosity of 0.525 dL / g were vacuum dried at 130°C for 12 hours, heated and melted by a secondary screw, and accurately metered by a metering pump before being transported into a spinning manifold. Within the spinning manifold, the chips were evenly distributed to the island-in-the-sea composite spinning device.

[0030] Step 3) The melts of titanium-based polyethylene terephthalate (Ti-PET) and titanium-based water-soluble polyester (Ti-COPET) are synchronously injected into the spinneret inside the island-in-sea composite spinning device. The temperature of the composite spinning device is 288°C. After composite, several fiber monofilaments with an island structure are extruded, and cooled by side blowing and spinning tunnel, wherein the blowing cooling temperature is 11.5°C and the blowing cooling air pressure is 100Pa. Then, the monofilaments are successively subjected to a bunching and oiling treatment and wound by a winding machine at a speed of 3000m / min to obtain a raw yarn. The raw yarn is then subjected to a drawing treatment, wherein the temperature of the hot roller is 90°C, the temperature of the hot plate is 150°C, the drawing ratio is 1.8, and the winding speed is 150m / min to obtain a green polyester island fiber.

[0031] Comparative Example 1

[0032] Conventional antimony-based polyethylene terephthalate with an intrinsic viscosity of 0.685 dL / g was selected as the island component, and antimony-based water-soluble polyester with an intrinsic viscosity of 0.525 dL / g was selected as the sea component. The two were screw-molded at a mass ratio of 70:30 for high-temperature melt extrusion to produce green polyester sea-island composite spinning. The specific steps are as follows:

[0033] Step 1) Conventional antimony-based polyethylene terephthalate (PET) chips with an intrinsic viscosity of 0.685 dL / g are vacuum dried at 130°C for 12 hours, then mixed with 1 wt% compatibilizer and 3 wt% biochar enhancer (dried at 120°C for 4 hours), and melt-extruded into pellets through a twin-screw extruder; after drying, the modified pellets are heated and melted by the spinning main screw, and accurately measured by a metering pump and transported to the spinning manifold, and evenly distributed to the island-in-the-sea composite spinning device in the spinning manifold.

[0034] Step 2) The antimony-based water-soluble polyester chips with an intrinsic viscosity of 0.525 dL / g were vacuum dried at 130° C. for 12 hours, heated and melted by a secondary screw, accurately metered by a metering pump, and transported into the spinning manifold, and evenly distributed into the island-in-the-sea composite spinning device within the spinning manifold.

[0035] Step 3) The melts of conventional antimony-modified polyethylene terephthalate and antimony-based water-soluble polyester are synchronously injected into the spinneret inside the island composite spinning device. The temperature of the composite spinning device is 288°C. After compounding, several fiber monofilaments with an island structure are extruded, and cooled by side blowing and spinning tunnel, wherein the blowing cooling temperature is 11.5°C and the blowing cooling air pressure is 100Pa. Then, the monofilaments are subjected to bundle oiling treatment and winding at a speed of 3000m / min to obtain the raw yarn. The raw yarn is then subjected to a drawing treatment, wherein the temperature of the hot roller is 90°C, the temperature of the hot plate is 150°C, the drawing ratio is 1.8, and the winding speed is 150m / min to obtain the conventional modified polyester island fiber.

[0036] Comparative Example 2

[0037] Conventional antimony-based polyethylene terephthalate with an intrinsic viscosity of 0.685 dL / g was selected as the island component, and antimony-based water-soluble polyester with an intrinsic viscosity of 0.525 dL / g was selected as the sea component. The two were screw-molded at a mass ratio of 80:20 for high-temperature melt extrusion to produce green polyester sea-island composite spinning. The specific steps are as follows:

[0038] Step 1) Conventional antimony-based polyethylene terephthalate chips with an intrinsic viscosity of 0.685 dL / g are vacuum dried at 130° C. for 12 hours, heated and melted by a main screw, accurately metered by a metering pump, and transported into a spinning manifold, where they are evenly distributed to the island-in-the-sea composite spinning device.

[0039] Step 2) The antimony-based water-soluble polyester chips with an intrinsic viscosity of 0.525 dL / g were vacuum dried at 130° C. for 12 hours, heated and melted by a secondary screw, accurately metered by a metering pump, and transported into the spinning manifold, and evenly distributed into the island-in-the-sea composite spinning device within the spinning manifold.

[0040] Step 3) The melts of conventional antimony-based polyethylene terephthalate and antimony-based water-soluble polyester are simultaneously injected into the spinneret inside the island composite spinning device. The temperature of the composite spinning device is 288°C. After compounding, several fiber monofilaments with an island structure are extruded, and cooled by side blowing and spinning tunnel, wherein the blowing cooling temperature is 11.5°C and the blowing cooling air pressure is 100Pa. Then, the monofilaments are subjected to bundle oiling treatment and winding at a speed of 3000m / min to obtain the raw yarn. The raw yarn is then subjected to a drawing treatment, wherein the temperature of the hot roller is 90°C, the temperature of the hot plate is 150°C, the drawing ratio is 1.8, and the winding speed is 150m / min to obtain conventional polyester island fiber.

[0041] The following is a comparison of the mechanical properties of the polyester sea-island fibers prepared in Examples 1-2 and Comparative Examples 1-2. The specific testing methods are as follows:

[0042] 1) Fiber cross-section detection: A fiber cross-section sample was prepared using a Hastelloy slicer and a single-sided blade, and the cross-section morphology was observed and photographed using a microscope with a magnification of 500 times.

[0043] 2) Heavy metal element detection: X-ray fluorescence spectrometer was used for testing. A small amount of fiber sample was dissolved in hexafluoroisopropanol and then coated into a film. After removing the solvent, the polyester film was used for testing.

[0044] 3) Fiber opening performance test: A certain mass of fiber sample was treated with 3% sodium hydroxide aqueous solution at 80°C for 30 minutes. The fiber was then washed, dried and weighed. The water solubility of the fiber was calculated based on the mass difference before and after treatment to determine the fiber opening performance.

[0045] 4) Breaking strength and elongation at break: The test was conducted using an electronic single yarn strength tester with a fiber clamping length of 200 mm, a tensile rate of 50 mm / min, and a pre-tension of 5 cN. Each set of samples was tested 15 times, and the average values were taken to obtain the breaking strength and elongation of the fiber.

[0046] The following are the performance test results of the polyester sea-island fibers prepared in Examples 1-2 and Comparative Examples 1-2 of this case, as shown in the table below.

[0047]

[0048]

[0049] The results in Table 1 show that compared with Comparative Examples 1 and 2, Examples 1 and 2 can achieve the removal of heavy metal elements while ensuring that the mechanical properties and fiber opening effects are basically consistent with those of the comparative examples prepared from conventional raw materials, thereby effectively protecting the environment and reducing pollution.

[0050] The technical solution of this invention utilizes a titanium-based catalyst instead of an antimony-based catalyst to treat polyester, uses environmentally friendly polyester as the raw material for preparing island-in-the-sea fibers, and adds a compatibilizer and a biochar enhancer to the island component raw material. These key technical features contribute to the production of a bicomponent island-in-the-sea composite fiber using titanium-based polyethylene terephthalate (Ti-PET) as the island component and titanium-based water-soluble polyester (Ti-COPET) as the sea component. These components can be configured using existing technology by those skilled in the art, and this invention does not require specific model selection or combination.

[0051] Thus, by adopting the technical solution of the present invention, in the preparation method of the green polyester sea island fiber, the method of melt extrusion of polyester in the component pretreatment process can effectively reduce energy consumption, avoid large amounts of carbon emissions interacting with other air pollutants to cause environmental pollution, enhance green environmental protection performance, and protect the environment.

[0052] From the above description, it can be found that compared with the existing technology, after adopting the technical solution of the present invention, titanium polyester and titanium water-soluble polyester are used as the island component and the sea component respectively, which can effectively reduce the environmental pollution problems existing in post-processing processes such as fiber opening and dyeing. For example: the heavy metals contained in the component polyester migrate to the water body and cause water pollution. The fiber has good mechanical properties and can be used as an ultrafine fiber after fiber opening treatment in many fields such as artificial leather, highly absorbent fabrics and clean cloths.

[0053] The above describes the technical solution, working process and implementation effect of the present invention in detail. It should be noted that what is described is only a typical example of the present invention. In addition, the present invention can also have many other specific implementation methods. Any technical solution formed by equivalent replacement or equivalent transformation falls within the scope of protection required by the present invention.

Claims

1. A green polyester sea-island fiber, comprising an island component and a sea component, characterized in that: The island component is titanium-based polyethylene terephthalate, which contains a compatibilizer and a biochar enhancer; the sea component is titanium-based water-soluble polyester; the green polyester sea island fiber has a linear density of 60 to 100 dtex, a breaking strength of 2.5 to 3.5 cN / dtex, and an elongation at break of 20 to 40%.

2. The method for preparing the green polyester sea-island fiber according to claim 1, characterized in that: The following steps are involved: Step S1: After vacuum drying, the island component and sea component raw materials are melt-extruded by screws and quantitatively delivered into the spinning manifold by a metering pump, and further evenly distributed into the sea-island composite spinning device in the spinning manifold; Step S2: The island component and the sea component are then simultaneously injected into the spinneret inside the island-in-the-sea composite spinning device. After composite, several fiber monofilaments with an island-in-the-sea structure are ejected. After air-cooling treatment, oiling treatment and winding treatment, the raw yarn is obtained, and then the green polyester island fiber is obtained by drawing treatment.

3. The method for preparing green polyester sea-island fibers according to claim 2, wherein: In step S1, the proportion of the island component and the sea component is accurately controlled by a metering pump, and unmelted particles are removed through a 100-200 mesh sieve. The pump supply of the island component is 40-50 g / min, and the metering pump speed is 25-30 r / min; the pump supply of the sea component is 20-30 g / min, and the metering pump speed is 25-30 r / min.

4. The method for preparing green polyester sea-island fibers according to claim 2, wherein: In the step S2, the spinning temperature of the island-in-the-sea composite spinning device is 285-290°C.

5. The method for preparing the green polyester sea-island fiber according to claim 2, wherein: In step 2, the air blowing cooling treatment adopts a side blowing method with a wind speed of 0.3-0.8 m / s, a side blowing temperature of 10-18° C., a side blowing humidity of 60-70%, and a side blowing pressure of 100-200 Pa.

6. The method for preparing green polyester sea-island fibers according to claim 2, wherein: In the step S2, the winding process adopts a winding speed of 2500 to 3500 m / min.

7. The method for preparing green polyester sea-island fibers according to claim 2, wherein: In step S2, the raw yarn drawing process adopts hot roller-hot plate drawing, the drawing ratio is 1.5-3.5, and the drawing speed is 100-150 m / min.

8. Use of the green polyester sea-island fiber according to claim 1 in the fields of imitation leather fabrics, high-grade fabrics or filter membranes.

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