Multifunctional polyester fiber and preparation method thereof

Abstract

The present invention relates to a multifunctional polyester fiber and a preparation method thereof, and belongs to the technical field of functional fibers. The preparation method of the present invention comprises the following steps: S1, a zirconium salt and trimesic acid are subjected to hydrothermal reaction in a solvent, and Zr-MOF is obtained by centrifugation, washing, and drying; S2, Zr-MOF is calcined under a protective atmosphere to obtain a Zr-MOF derivative; S3, Zr-MOF derivative and polyester powder are granulated to obtain a multifunctional polyester masterbatch; S4, the multifunctional polyester masterbatch and polyester chips are spun to obtain the multifunctional polyester fiber, which has good far-infrared effect, heat storage and warmth retention effect, antistatic effect, and mechanical properties.

Description

Technical Field

[0001] The invention belongs to the technical field of functional fibers, and in particular relates to a multifunctional polyester fiber and a preparation method thereof. Background Art

[0002] Polyethylene terephthalate, also known as polyester, has the advantages of high strength, not easy to deform, corrosion resistance, and low cost. Far-infrared polyester fiber is widely used in the fields of fillings and clothing. The far-infrared rays it radiates can increase the body temperature, penetrate deep into the skin, promote blood circulation, and achieve multiple functions of heat preservation and health care. At present, far-infrared polyester fiber mainly uses materials that can absorb and emit far-infrared, such as biochar (such as bamboo charcoal), carbon fiber, tourmaline, far-infrared ceramics, jade, Tai Chi stone, metal oxides and silicon carbide.

[0003] Chinese invention patent CN 107641297 A discloses a heat storage and heat preservation functional masterbatch, its products and preparation method, which combines ceramic powders such as tungsten bronze compounds, antimony-doped, fluorine-doped or antimony-fluorine co-doped tin oxide, titanium nitride or a combination thereof with a polymer carrier such as polyester to prepare a heat storage and heat preservation functional masterbatch and fiber products. However, the far-infrared heating performance of inorganic nanopowder-modified polyester fibers needs to be further improved. Chinese invention patent CN 116356440 A discloses a modified Taiji stone and its application in far-infrared health-care degradable copolyester fibers. Taiji stone powder is modified by polyglycol containing alkyl side chains and phthalate coupling agent, and then the modified Taiji stone is added by copolymerization. However, the copolymerization method is technically difficult and cannot achieve large-scale addition of materials. In addition, there are great challenges in further improving the far-infrared performance of inorganic nanopowders.

[0004] In addition, polyester fiber is a hydrophobic fiber with high electrical insulation properties, which makes it easy for static charge to accumulate and discharge during production and use. The resulting fire may cause significant loss of life and property.

[0005] Metal-Organic Frameworks (MOFs) are a new type of porous crystalline material formed by metals or metal clusters and organic ligands through coordination bonds. MOFs materials have ultra-high specific surface area and porosity, and have the characteristics of easy surface functionalization, designability, controllable particle size, and adjustable pore size. It is of great significance to develop far-infrared thermal insulation and antistatic polyester fibers using the high porosity and easy functionalization and adjustment characteristics of MOFs materials, but there are no related research reports and there are great challenges. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides a multifunctional polyester fiber and a preparation method thereof. Firstly, a zirconium-rich metal organic framework material (Zr-MOF) is prepared by a hydrothermal method using zirconium salt and trimesic acid, and then a Zr-MOF derivative is prepared by calcination. Finally, the Zr-MOF derivative and a polyester material are granulated by melt blending and spun by melt spinning to prepare the multifunctional polyester fiber.

[0007] The first object of the present invention is to provide a method for preparing a multifunctional polyester fiber, comprising the following steps:

[0008] S1, zirconium salt and trimesic acid are subjected to hydrothermal reaction in a solvent, and Zr-MOF is obtained by centrifugation, washing and drying;

[0009] S2. Under a protective atmosphere, calcining the Zr-MOF described in S1 to obtain a Zr-MOF derivative;

[0010] S3, granulating the Zr-MOF derivative and polyester powder described in S2 to obtain a multifunctional polyester masterbatch;

[0011] S4, spinning the multifunctional polyester masterbatch and polyester chips described in S3 to obtain the multifunctional polyester fiber.

[0012] In one embodiment of the present invention, in S1, the zirconium salt is selected from one or more of zirconium tetrachloride, zirconium nitrate and zirconium sulfate.

[0013] In one embodiment of the present invention, in S1, the molar ratio of the zirconium salt to trimesic acid is 1:1-1.2.

[0014] In one embodiment of the present invention, in S1, the temperature of the hydrothermal reaction is 110°C-130°C, and the time is 20h-30h.

[0015] In one embodiment of the present invention, in S1, the solvent is N,N-dimethylformamide.

[0016] In one embodiment of the present invention, in S2, the calcination temperature is 500°C-700°C, and the calcination time is 2h-4h.

[0017] In one embodiment of the present invention, before S3, the step of drying the Zr-MOF derivative and the polyester powder is also included, the drying temperature of the Zr-MOF derivative is 80°C-100°C, and the drying time is 7h-9h; the drying temperature of the polyester powder is 120°C-130°C, and the time is 10h-12h.

[0018] In one embodiment of the present invention, in S3, the granulation is performed by melt blending, extrusion molding, cooling and pelletizing through a twin-screw extruder; the process parameters of the granulation are: a rotation speed of 250rpm-400rpm, and a temperature of 250℃-270℃; if the processing temperature is too low, the Zr-MOF derivative and the polyester powder cannot be mixed evenly, which is not conducive to granulation, and if the temperature is too high, it will cause energy waste.

[0019] In one embodiment of the present invention, in S3, the mass fraction of the Zr-MOF derivative in the multifunctional polyester masterbatch is 20%-25%.

[0020] In one embodiment of the present invention, before S4, it also includes a step of drying the multifunctional polyester masterbatch and polyester chips, wherein the drying is performed by pre-crystallization at 90°C-110°C for 3h-4h, and then drying at 120°C-140°C for 10h-15h to ensure that the final moisture content of the multifunctional polyester masterbatch and polyester chips is less than 100ppm.

[0021] In one embodiment of the present invention, in S4, the spinning is performed by a melt spinning machine, followed by oiling, pre-stretching, winding, and stretching; the spinning process parameters are: a speed of 2500m / min-2800m / min, a temperature of 280℃-290℃, and a pulling ratio of 1.5-2.

[0022] In one embodiment of the present invention, in S4, the mass fraction of the multifunctional polyester masterbatch in the multifunctional polyester fiber is 8%-12%.

[0023] The second object of the present invention is to provide a multifunctional polyester fiber prepared by the method.

[0024] In one embodiment of the present invention, the far-infrared normal emissivity of the multifunctional polyester fiber is 0.90-0.93, the far-infrared radiation temperature rise is 2.1°C-3.0°C, the surface temperature rise is 20.5°C-25.6°C higher than that of ordinary fibers, the antistatic property reaches Class A, and the breaking strength is 3.2cN / detx-3.4cN / detx.

[0025] The technical solution of the present invention has the following advantages compared with the prior art:

[0026] The zirconium salt and trimesic acid used in the preparation method of the present invention have excellent coordination and chelating properties. The two are self-assembled through coordination bond bridging to form a periodic network porous Zr-MOF. Carbon-rich and oxygen-rich Zr-MOF derivatives are obtained by calcination, and the good pore structure of Zr-MOF is retained, which is helpful for storing still air. Its carbon-rich porous structure helps to improve the far-infrared performance of the calcined Zr-MOF derivative; in addition, the carbon-based material and zirconium-rich structure of the Zr-MOF derivative can act as conductive fillers; therefore, the Zr-MOF derivative has good far-infrared effect, heat storage and warmth retention effect and antistatic effect.

[0027] The preparation method of the present invention prepares a Zr-MOF derivative by a hydrothermal method and a calcination method. The Zr-MOF derivative is rich in aromatic carbon-based materials in its structure and has good compatibility with polyester fibers. In addition, the Zr-MOF derivative has the characteristics of being lightweight and porous, which can reduce the amount of material added, so the modified polyester fiber retains good mechanical properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments of the present invention in conjunction with the accompanying drawings, wherein:

[0029] Figure 1 It is a near-infrared light heat storage test curve diagram of the unmodified polyester fiber and the modified polyester fiber in Test Example 1 of the present invention. DETAILED DESCRIPTION

[0030] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. It should be understood that the specific embodiments are only used to explain the present invention, but the embodiments are not intended to limit the present invention.

[0031] In the present invention, unless otherwise explained, technical and scientific terms used in the present invention have the same meanings as commonly understood by those skilled in the art to which the present invention belongs.

[0032] In the present invention, unless otherwise stated, the term "and / or" used in the present invention includes any and all combinations of one or more of the associated listed items.

[0033] In the present invention, unless otherwise stated, the experimental methods used in the embodiments of the present invention are conventional methods unless otherwise stated, and the materials, reagents, etc. used are all commercially available unless otherwise stated. Example 1

[0034] The multifunctional polyester fiber and the preparation method thereof of the present invention specifically comprise the following steps:

[0035] S1. Dissolve zirconium tetrachloride and trimesic acid in N,N-dimethylformamide (zirconium tetrachloride concentration is 1 / 210 g / mL) at a molar ratio of 1:1.1, place it in a polytetrafluoroethylene reactor and react at 120°C for 25 hours, then centrifuge, wash with ethanol, and dry to obtain Zr-MOF;

[0036] S2. calcining Zr-MOF at 600°C under nitrogen atmosphere for 3 h to obtain a Zr-MOF derivative;

[0037] S3, Zr-MOF derivatives were vacuum dried at 90°C for 8h; polyester powder was vacuum dried at 125°C for 11h, and after mixing, melt blending, extrusion molding, cooling and pelletizing were carried out through a twin-screw extruder. The speed of the twin-screw extruder was 320rpm and the temperature was 260°C to obtain a multifunctional polyester masterbatch with a mass fraction of 22% of Zr-MOF derivatives;

[0038] S4, the multifunctional polyester masterbatch and the polyester chips were pre-crystallized in a 100°C blast oven for 3.5 hours, and then dried at 130°C for 12.5 hours to make the final moisture content of the multifunctional polyester masterbatch and the polyester chips less than 100 ppm. After mixing, they were spun through a melt spinning machine, cooled and oiled, pre-stretched, wound, and stretched. The speed of the melt spinning machine was 2650 m / min, the temperature was 285°C, and the traction ratio was 1.8, to obtain a multifunctional polyester fiber with a mass fraction of 10% of the multifunctional polyester masterbatch. Example 2

[0039] The multifunctional polyester fiber and the preparation method thereof of the present invention specifically comprise the following steps:

[0040] S1. Dissolve zirconium nitrate and trimesic acid in N,N-dimethylformamide (zirconium nitrate concentration is 1 / 180 g / mL) at a molar ratio of 1:1, place it in a polytetrafluoroethylene reactor and react at 110°C for 30 hours, then centrifuge, wash with ethanol, and dry to obtain Zr-MOF;

[0041] S2. calcining Zr-MOF at 500°C under nitrogen atmosphere for 4 h to obtain a Zr-MOF derivative;

[0042] S3, Zr-MOF derivatives were vacuum dried at 80°C for 9h; polyester powder was vacuum dried at 120°C for 12h, and after mixing, melt blended, extruded, cooled and pelletized by a twin-screw extruder. The speed of the twin-screw extruder was 250rpm and the temperature was 270°C to obtain a multifunctional polyester masterbatch with a mass fraction of 20% of Zr-MOF derivatives;

[0043] S4, the multifunctional polyester masterbatch and the polyester chips were pre-crystallized in a 90°C blast oven for 4 hours, and then continued to be dried at 120°C for 15 hours, so that the final moisture content of the multifunctional polyester masterbatch and the polyester chips was less than 100 ppm. After mixing, they were spun through a melt spinning machine, cooled and oiled, pre-stretched, wound, and stretched. The speed of the melt spinning machine was 2500 m / min, the temperature was 290°C, and the traction ratio was 1.5, to obtain a multifunctional polyester fiber with a mass fraction of 8% of the multifunctional polyester masterbatch. Example 3

[0044] The multifunctional polyester fiber and the preparation method thereof of the present invention specifically comprise the following steps:

[0045] S1. Dissolve zirconium sulfate and trimesic acid in N,N-dimethylformamide (zirconium sulfate concentration is 1 / 240 g / mL) at a molar ratio of 1:1.2, place it in a polytetrafluoroethylene reactor and react at 130°C for 20 hours, then centrifuge, wash with ethanol, and dry to obtain Zr-MOF;

[0046] S2. calcining Zr-MOF at 700°C under nitrogen atmosphere for 2 h to obtain a Zr-MOF derivative;

[0047] S3, Zr-MOF derivatives were vacuum dried at 100°C for 7h; polyester powder was vacuum dried at 130°C for 10h, and after mixing, melt blended, extruded, cooled and pelletized by a twin-screw extruder. The speed of the twin-screw extruder was 400rpm and the temperature was 250°C to obtain a multifunctional polyester masterbatch with a mass fraction of 25% of Zr-MOF derivatives;

[0048] S4, the multifunctional polyester masterbatch and the polyester chips were pre-crystallized in a 110°C blast oven for 3 hours, and then continued to be dried at 140°C for 10 hours, so that the final moisture content of the multifunctional polyester masterbatch and the polyester chips was less than 100 ppm. After mixing, they were spun through a melt spinning machine, cooled and oiled, pre-stretched, wound and stretched. The speed of the melt spinning machine was 2800 m / min, the temperature was 280°C, and the pulling ratio was 2, so as to obtain a multifunctional polyester fiber with a mass fraction of 12% of the multifunctional polyester masterbatch. Comparative Example 1

[0049] The same as Example 1, except that trimesic acid is replaced by citric acid. Comparative Example 2

[0050] Basically the same as Example 1, except that: S2 treatment is not performed. Comparative Example 3

[0051] The process is basically the same as Example 1, except that the calcination temperature is 300° C. and the calcination time is 4 h.

[0052] Test Example 1

[0053] The far infrared properties of the multifunctional polyester fibers (modified polyester fibers) prepared in Examples 1-3 and Comparative Examples 1-3 were tested:

[0054] Far infrared performance: Refer to GB / T 30127-2013 "Testing and evaluation of far infrared performance of textiles" to test the far infrared emissivity and heating performance of modified polyester fiber;

[0055] Photothermal performance: Refer to GB / T 18319-2019 "Test method for photothermal performance of textiles" to test the photothermal performance of thermal insulation flame-retardant polyester fiber, with an irradiance of 150W / m 2 ;

[0056] Antistatic performance: Refer to GB / T 14342-2015 "Test method for specific electrical resistance of chemical staple fibers" to test the antistatic performance of modified polyester fibers;

[0057] Physical properties: Refer to GB / T 14344-2022 "Test method for tensile properties of chemical fiber filaments" to test the breaking strength of modified polyester fiber.

[0058] Figure 1 It is a near infrared light heat storage test curve diagram of the unmodified polyester fiber and the modified polyester fiber of Example 1;

[0059] Table 1 shows the relevant properties of the unmodified polyester fiber and the modified polyester fiber finally measured:

[0060] Table 1

[0061]

[0062] From Table 1 and Figure 1 It can be seen that the polyester fiber modified with Zr-MOF derivatives has excellent far-infrared effect, heat storage and warmth retention effect and antistatic effect.

[0063] Comparison between Comparative Example 1 and Example 1 shows that after the polyester fiber is modified by the chelate product of citric acid and zirconium salt, the far-infrared effect and heat storage and warmth retention effect of the polyester fiber are poor. This is because citric acid is a ternary aliphatic carboxylic acid and cannot form a regular porous MOF structure with zirconium metal salt. The product after calcination is zirconium oxide powder, which leads to deviation in the effect.

[0064] Comparison between Comparative Example 2 and Example 1 shows that after the polyester fiber is modified with the uncalcined Zr-MOF derivative, its far-infrared effect and heat storage and warmth retention effect are poor, and its antistatic performance is poor. This is because the uncalcined Zr-MOF derivative only relies on the porous structure to improve its heat storage and warmth retention effect, while the carbon structure of the calcined Zr-MOF derivative has good far-infrared absorption effect and conductive properties.

[0065] Comparison between Comparative Example 3 and Example 1 shows that after the polyester fiber is modified with an insufficiently calcined Zr-MOF derivative, its far-infrared effect and heat storage and warmth retention effect are poor, and its antistatic performance is poor. This is because the insufficiently calcined Zr-MOF derivative only relies on the porous structure to improve its heat storage and warmth retention effect, while the carbon structure of the sufficiently calcined Zr-MOF derivative has good far-infrared absorption effect and conductive properties.

[0066] Obviously, the above embodiments are merely examples for clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the protection scope of the invention.

Claims

1. A method for preparing a multifunctional polyester fiber, characterized in that: The following steps are involved: S1, zirconium salt and trimesic acid are subjected to hydrothermal reaction in a solvent, and Zr-MOF is obtained by centrifugation, washing and drying; the molar ratio of the zirconium salt to trimesic acid is 1:1-1.2; S2. Under a protective atmosphere, calcining the Zr-MOF described in S1 to obtain a Zr-MOF derivative; the calcination temperature is 500° C.-700° C., and the time is 2 h-4 h; S3, granulating the Zr-MOF derivative and polyester powder described in S2 to obtain a multifunctional polyester masterbatch; S4, spinning the multifunctional polyester masterbatch and polyester chips described in S3 to obtain the multifunctional polyester fiber.

2. The method for preparing the multifunctional polyester fiber according to claim 1, characterized in that: In S1, the zirconium salt is selected from one or more of zirconium tetrachloride, zirconium nitrate and zirconium sulfate.

3. The method for preparing the multifunctional polyester fiber according to claim 1, characterized in that: In S1, the temperature of the hydrothermal reaction is 110°C-130°C, and the time is 20h-30h.

4. The method for preparing the multifunctional polyester fiber according to claim 1, characterized in that: In S3, the granulation is performed by melt blending, extrusion molding, cooling and pelletizing through a twin-screw extruder; the process parameters of the granulation are: a rotation speed of 250 rpm-400 rpm and a temperature of 250° C.-270° C.

5. The method for preparing the multifunctional polyester fiber according to claim 1, characterized in that: In S3, the mass fraction of the Zr-MOF derivative in the multifunctional polyester masterbatch is 20%-25%.

6. The method for preparing the multifunctional polyester fiber according to claim 1, characterized in that: In S4, the spinning is carried out by a melt spinning machine, followed by oiling after cooling, pre-stretching, winding, and stretching; the spinning process parameters are: speed of 2500m / min-2800m / min, temperature of 280℃-290℃, and traction ratio of 1.5-2.

7. The method for preparing the multifunctional polyester fiber according to claim 1, characterized in that: In S4, the mass fraction of the multifunctional polyester masterbatch in the multifunctional polyester fiber is 8%-12%.

8. A multifunctional polyester fiber prepared by the method according to any one of claims 1 to 7.

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