Moisture-absorbing antistatic pet copolyester fiber based on polyester polyol, and preparation method and fabric preparation method thereof

Abstract

The application discloses a kind of based on polyester polyol's hygroscopic antistatic PET copolyester fiber and its preparation method and fabric preparation method. Among them, the based on polyester polyol's high hygroscopic antistatic PET copolyester fiber is the filament that hydrophilic antistatic PET copolyester chip is prepared by melt spinning processing, and the hydrophilic antistatic PET copolyester chip is obtained by embedding functional polyester polyol as functional additive monomer into PET macromolecular chain copolymerization, and the PET copolyester fiber is intrinsic hygroscopic antistatic fiber and is used to process into durable antistatic fabric.The application solves the technical problems that the moisture absorption and antistatic effect of terylene fiber in the prior art and the poor mechanical properties of the fiber are poor.

Description

Technical Field

[0001] This invention relates to the field of functional chemical fiber manufacturing technology, and more specifically, to a moisture-absorbing and antistatic PET copolyester fiber based on polyester polyol, its preparation method, and its fabric preparation method. Background Technology

[0002] Polyethylene terephthalate (PET) is a thermoplastic polymer produced by melt polymerization of terephthalic acid (PTA) and ethylene glycol (EG). It possesses advantages such as high mechanical strength, stable thermal properties, excellent chemical resistance, and low cost, making it widely used in industrial and textile fields. Polyester fiber, produced by melt spinning of PET, is currently the most widely used chemical fiber in the textile industry, accounting for over 80% of the chemical fiber market share. However, due to the regular structure, high crystallinity and orientation of PET macromolecular segments, and the lack of hydrophilic groups on the molecular chain, polyester fiber has two inherent defects: firstly, poor moisture absorption, with a standard moisture regain of only 0.4%, resulting in low fabric comfort; secondly, a high tendency for static charge to accumulate, leading to a surface resistivity as high as 10⁻⁶. 15 The volume resistivity is as high as 10. 13 Electrostatic discharge (ESD) not only causes numerous difficulties in the production and processing of fibers and fabrics due to electrostatic adsorption, but also causes close-fitting wrapping and discharge stimulation when wearing fabrics. In severe cases, it may even cause fires or explosions due to electric sparks generated by electrostatic discharge.

[0003] Currently, there are three main methods to improve the moisture absorption and antistatic properties of polyester fabrics: First, surface coating, which involves applying a hydrophilic film-forming agent or conductive solution to the surface of the fiber or fabric. While simple to operate, the antistatic performance depends on the surface layer, making it unstable. The coating is easily detached and weakened during washing and friction, failing to achieve durable antistatic effects. Second, antistatic agent blending, which involves blending antistatic agents with PET and then extruding, granulating, and melt spinning to produce fibers. While this method offers some durability, the poor compatibility between the antistatic agent and the polyester matrix significantly increases the difficulty of melt spinning and can easily lead to a decrease in fiber strength and damage to fiber mechanical properties. Third, functional monomer copolymerization, which introduces highly hygroscopic or conductive functional monomers during fiber synthesis. Theoretically, the resulting fibers can possess intrinsic moisture absorption and antistatic effects and are not easily washed away. However, this method requires advanced polymerization technology, and existing copolymer systems are prone to functional chain segment decomposition or migration under the high temperatures of melt spinning, making it difficult to simultaneously achieve ideal moisture absorption and antistatic effects with fiber mechanical properties. Furthermore, current research and applications of polyester polyols mostly focus on their use as chain extenders in polyurethane synthesis, with few applications using them as functional comonomers introduced into the PET macromolecular chain to permanently impart intrinsic moisture-wicking and antistatic properties to polyester fibers through chemical bonding. In summary, existing polyester fibers suffer from poor moisture absorption and are prone to static electricity buildup due to the lack of hydrophilic groups in their molecular chains. Existing modification methods such as surface coating, antistatic agent blending, and functional monomer copolymerization all have inherent drawbacks, making it difficult to simultaneously achieve durable moisture-wicking and antistatic effects while maintaining the fiber's mechanical properties.

[0004] There is currently no effective solution to the above problems. Summary of the Invention

[0005] This invention provides a moisture-absorbing and antistatic PET copolyester fiber based on polyester polyol, its preparation method, and its fabric preparation method, so as to at least solve the technical problems of poor moisture-absorbing and antistatic effect and poor fiber mechanical properties of polyester fibers in the prior art.

[0006] According to one aspect of the present invention, a highly hygroscopic and antistatic PET copolyester fiber based on polyester polyol is provided. The PET copolyester fiber is a filament prepared by melt spinning of hydrophilic antistatic PET copolyester chips. The hydrophilic antistatic PET copolyester chips are obtained by copolymerizing functional polyester polyols as functional additive monomers embedded in the PET macromolecular chain. The PET copolyester fiber is an intrinsically hygroscopic and antistatic fiber and is used to process it into durable antistatic fabrics.

[0007] Furthermore, the aforementioned hydrophilic antistatic PET copolyester chips are polymers obtained by block copolymerization of two different types of alcohols. The structure of the polymer includes: a first type of repeating unit composed of terephthaloyl residues and aliphatic diol residues -O-(CH2). p The aliphatic diols are selected from ethylene glycol, 1,3-propanediol, and 1,4-butanediol, forming polyethylene terephthalate, propylene terephthalate, and butylene terephthalate segments, respectively. The number of repetitions of the first type of repeating unit is x. The second type of repeating unit is composed of a terephthaloyl residue and an ether-bonded diol residue -O-(CH2). a The structure consists of -O-(CH2)-O-, where the ether-containing diol residues are derived from one or more polyester polyols in the ether-containing series, corresponding to the formation of polyethylene terephthalate segments, polyethylene terephthalate segments, and polyethylene terephthalate segments. The number of repetitions of the second type of repeating unit is y; where x and y are positive integers.

[0008] Furthermore, the aforementioned polyester polyols containing ether bonds are polyethylene glycol.

[0009] According to another aspect of the present invention, a method for preparing highly hygroscopic and antistatic PET copolyester fibers based on polyester polyols as described in any one of the above embodiments is also provided. The method includes: step S1, placing hydrophilic antistatic PET copolyester chips in a vacuum drum drying oven for crystallization drying treatment; after the hydrophilic antistatic PET copolyester chips are fully dried, conveying them to the feed hopper of a spinning machine; step S2, the hydrophilic antistatic PET copolyester chips enter a screw extruder through the feed hopper, and the screw extruder extrudes and heats the hydrophilic antistatic PET copolyester chips to melt them into a copolyester melt; step S3, ... The copolyester melt is precisely metered by a metering pump and then extruded through a spinneret to form nascent fibers. In step S4, the nascent fibers are cooled and shaped by multi-stage air-temperature ring blowing to solidify and shape them. In step S5, the cooled and shaped nascent fibers are bundled and oiled. In step S6, the oiled nascent fibers are drawn and oriented by a multi-stage drawing system to obtain high-moisture-absorbing and antistatic PET copolyester fibers based on polyester polyols. In step S7, the high-moisture-absorbing and antistatic PET copolyester fibers based on polyester polyols are inspected and graded according to the inspection results to obtain finished fibers.

[0010] Furthermore, in step S1 above, the crystallization drying process is carried out under vacuum conditions, and the vacuum pressure inside the vacuum drum drying oven is 10 Pa; the crystallization drying process specifically includes: first, crystallizing the hydrophilic antistatic PET copolyester chips at a crystallization temperature of 90~100℃ for 2~3 hours, and then drying them at a drying temperature of 115~120℃ for 36~48 hours, so that the hydrophilic antistatic PET copolyester chips are fully dried.

[0011] Furthermore, in step S2 above, the screw extruder is divided into four temperature control zones along the material conveying direction. The extrusion heating is completed by temperature control in the four temperature control zones, and the temperature ranges of each temperature control zone are as follows: Zone I temperature is 200~220℃, Zone II temperature is 220~240℃, Zone III temperature is 240~260℃, and Zone IV temperature is 240~270℃.

[0012] Furthermore, in step S6 above, the multi-stage drawing system includes a first-stage drawing system and a second-stage drawing system arranged sequentially along the drawing direction; the drawing orientation includes: firstly, the oiled nascent fiber is drawn in the first-stage drawing system at a temperature of 100~120℃ and a drawing ratio of 3~4 times, and then secondly, the nascent fiber is drawn in the second-stage drawing system at a temperature of 125~140℃ and a drawing ratio of 1.2~1.5 times.

[0013] Furthermore, in step S1 above, the intrinsic viscosity of the hydrophilic antistatic PET copolyester chips placed in the vacuum drum drying oven is 0.67~0.78 dL / g, and the mass content of the functional polyester polyol embedded in the hydrophilic antistatic PET copolyester chips is 15wt%~35wt%.

[0014] Further, in step S6 above, the high moisture absorption and antistatic PET copolyester fiber based on polyester polyol obtained by the above drawing and orientation is a 75D / 36F filament; the 75D / 36F filament has a breaking strength of 3.6~4.0 cN / dtex, a breaking elongation of 21%~32%, a moisture regain of 0.7%~1.2%, and a volume resistivity of 1.810. 6 ~2.310 7 cm.

[0015] According to another aspect of the present invention, a method for preparing a fabric is also provided, characterized in that it includes plain weaving the polyester polyol-based high moisture-absorbing and antistatic PET copolyester fiber obtained by the above-mentioned preparation method of polyester polyol-based high moisture-absorbing and antistatic PET copolyester fiber on a loom, and dyeing the woven fabric to obtain the above-mentioned durable antistatic fabric.

[0016] In this embodiment of the invention, a block copolymer chip is synthesized by embedding ether-bonded polyester polyols as functional monomers into the PET macromolecular chain. This is combined with multi-stage temperature-controlled melt spinning and plain weaving processes. During the polymerization stage, a block copolymer microstructure is constructed, consisting of a first type of repeating unit composed of terephthaloyl residues and aliphatic diol residues, and a second type of repeating unit composed of ether-bonded diol residues. This allows hydrophilic and antistatic groups to be permanently anchored to the polymer backbone via covalent bonds. This is further enhanced by step-by-step crystallization drying under 10Pa vacuum conditions, four-zone gradient temperature-controlled screw extrusion melting at 200-270℃, precise metering extrusion, multi-stage air-cooling and shaping, and two-stage gradient temperature control and multi-stage... Optimized melt spinning processes, including multi-stretching and orientation, followed by plain weaving and dyeing, achieve intrinsic and durable moisture absorption and antistatic properties in the PET macromolecular chains without compromising their original regularity, crystallinity, and orientation. This completely avoids the shortcomings of traditional surface coating methods, such as easy washing away of functional properties, and physical blending methods, such as significant decrease in fiber strength due to poor interfacial compatibility. It ensures that the fiber maintains excellent mechanical properties while possessing high moisture regain and low volume resistivity, and imparts excellent antistatic half-life to the fabric. This results in the fabric with a breaking strength of 3.6–4.0 cN / dtex, a breaking elongation of 21%–32%, a moisture regain of 0.7%–1.2%, and a volume resistivity as low as 1.810. 6 ~2.310 7 The intrinsic moisture-wicking and antistatic PET copolyester filament of cm, and the durable antistatic fabric woven from it has a static half-life of less than 1 second before and after washing. It has the technical effect of combining excellent mechanical properties, washability and long-lasting antistatic function, thus solving the technical problems of poor moisture-wicking and antistatic effect and poor fiber mechanical properties of polyester fibers in the prior art. Attached Figure Description

[0017] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a schematic diagram of an optional structural general formula of PET copolyester fiber based on polyester polyol with high moisture absorption and antistatic properties according to an embodiment of the present invention; Figure 2 This is a schematic flowchart of an optional method for preparing highly hygroscopic and antistatic PET copolyester fibers based on polyester polyols according to an embodiment of the present invention. Detailed Implementation

[0018] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0019] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "including" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0020] Example 1 According to an embodiment of the present invention, an embodiment based on polyester polyol highly hygroscopic and antistatic PET copolyester fiber is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0021] Figure 1 This is a schematic diagram of an optional structural formula of PET copolyester fiber based on polyester polyol with high moisture absorption and antistatic properties according to an embodiment of the present invention, as shown below. Figure 1 As shown, this PET copolyester fiber, based on polyester polyol and characterized by high moisture absorption and antistatic properties, is a filament prepared from hydrophilic antistatic PET copolyester chips through melt spinning. The hydrophilic antistatic PET copolyester chips are obtained by copolymerizing functional polyester polyols as functional additive monomers embedded in the PET macromolecular chain. The PET copolyester fiber is an intrinsically moisture-absorbing and antistatic fiber and is used to process durable antistatic fabrics. As an intrinsically moisture-absorbing and antistatic fiber, PET copolyester fiber exhibits excellent thermodynamic properties, high moisture regain, and superior antistatic performance. It can be processed into durable antistatic fabrics with excellent dyeing properties.

[0022] Optionally, the hydrophilic antistatic PET copolyester chips are polymers obtained by block copolymerization of two different types of alcohols. The structure of the polymer includes: a first type of repeating unit composed of terephthaloyl residues and aliphatic diol residues -O-(CH2). p The -O- group consists of aliphatic diols selected from ethylene glycol, 1,3-propanediol, and 1,4-butanediol, forming polyethylene terephthalate (PET) segments, propylene terephthalate (PPT) segments, and butylene terephthalate (PET) segments, respectively. The first type of repeating unit is repeated x times. The second type of repeating unit consists of a terephthaloyl residue and an ether-bonded diol residue -O-(CH2). a The -O-(CH2)-O- structure contains ether-bonded diol residues derived from one or more polyester polyols in the ether-bonded series, corresponding to the formation of polyethylene terephthalate segments, polyethylene terephthalate segments, and polyethylene terephthalate segments. The number of repetitions of the second type of repeating unit is y; where x and y are positive integers.

[0023] Optionally, the polyester polyol containing ether bonds is polyethylene glycol.

[0024] Optionally, such as Figure 1 The structural formula shown represents the microscopic block copolymer structure of the hygroscopic and antistatic PET copolyester macromolecular chain based on polyester polyol prepared in this invention. This structural formula intuitively reveals the technical solution of this invention to achieve synergistic fiber functionalization and high performance through molecular design. Specifically, the copolyester backbone is composed of two types of repeating unit blocks: the first type of repeating unit on the left is a traditional PET hard segment structure formed by the condensation polymerization of terephthaloyl residues and aliphatic diol residues (such as ethylene glycol residues, p is usually 2). This rigid segment endows the copolyester with excellent crystallinity, orientation and mechanical strength, and is the structural cornerstone that ensures the fiber breaking strength reaches 3.6~4.0 cN / dtex; the second type of repeating unit on the right is a functional soft segment structure formed by the condensation polymerization of terephthaloyl residues and polyester polyol residues containing ether bonds. The abundant flexible ether bonds in this structure have extremely strong hydrophilicity and chain segment mobility, which not only provides microscopic channels for water adsorption and electrostatic charge dissipation, giving the fiber high moisture regain and low volume resistivity, but also effectively improves the flexibility of the macromolecular chain and increases the breaking elongation.

[0025] Optionally, such as Figure 1In the structural formula shown, the subscripts x, y, and z represent the degree of polymerization of the hard segment and the soft segment, and the total number of chain segments, respectively. In actual preparation, by precisely controlling the ratio of x to y, a reasonable phase separation between the hard segment microregions and the soft segment microregions can be achieved, thereby constructing an ideal morphology of rigid framework support and flexible channel conduction at the microscopic level. Based on the copolymer model shown in this structural formula, this invention permanently anchors hydrophilic antistatic groups in the polymer backbone in the form of covalent bonds, completely overcoming the defects of easy migration of functional components and poor wash resistance in traditional physical blending or surface coating processes. This intrinsically functionalized design of chemical bonding, combined with the subsequent optimized multi-stage temperature-controlled melt spinning process, enables the resulting fiber to achieve a high degree of unity of moisture absorption, antistatic properties, and wash resistance while maintaining excellent mechanical properties.

[0026] Example 2 According to another aspect of the present invention, a method for preparing highly hygroscopic and antistatic PET copolyester fibers based on the polyester polyol in Example 1 is also provided. Figure 2 This is a schematic flowchart of an optional method for preparing highly hygroscopic and antistatic PET copolyester fibers based on polyester polyols according to an embodiment of the present invention. Figure 2 As shown, the preparation method of the highly hygroscopic and antistatic PET copolyester fiber based on polyester polyol includes: Step S1: Place the hydrophilic antistatic PET copolyester chips in a vacuum drum drying oven for crystallization drying. After the hydrophilic antistatic PET copolyester chips are fully dried, they are conveyed to the feed hopper of the spinning machine. In step S2, the hydrophilic antistatic PET copolyester chips are fed into the screw extruder through the feed hopper. The screw extruder extrudes and heats the hydrophilic antistatic PET copolyester chips to melt them and form a copolyester melt. Step S3: The copolyester melt is precisely metered by a metering pump and then extruded through a spinneret to form nascent fibers. Step S4: The nascent fibers are cooled and shaped by multi-stage air-temperature circulation, so that the nascent fibers are solidified and formed. Step S5: Bundle the cooled and shaped nascent fibers and apply an oiling treatment to the bundled nascent fibers. Step S6: The oiled nascent fibers are stretched and oriented through a multi-stage stretching system to obtain high moisture absorption and antistatic PET copolyester fibers based on polyester polyols. Step S7: Inspect the PET copolyester fiber based on polyester polyol with high moisture absorption and antistatic properties, and grade it according to the inspection results to obtain the finished fiber.

[0027] Optionally, in step S1, the crystallization drying process is carried out under vacuum conditions, and the vacuum pressure in the vacuum drum drying oven is 10 Pa. The crystallization drying process specifically includes: first, crystallizing the hydrophilic antistatic PET copolyester chips at a crystallization temperature of 90~100℃ for 2~3 hours, and then drying them at a drying temperature of 115~120℃ for 36~48 hours, so that the hydrophilic antistatic PET copolyester chips are fully dried.

[0028] Optionally, in step S2, the screw extruder is divided into four temperature control zones along the material conveying direction. The extrusion heating is completed by temperature control in the four temperature control zones, and the temperature ranges of each temperature control zone are as follows: Zone I temperature is 200~220℃, Zone II temperature is 220~240℃, Zone III temperature is 240~260℃, and Zone IV temperature is 240~270℃.

[0029] Optionally, in step S6, the oiled nascent fibers are drawn and oriented using a multi-stage drawing system to obtain thermodynamically stable, high moisture regain, and excellent antistatic properties of a polyester polyol-based high-moisture-absorbing and antistatic PET copolyester fiber. The multi-stage drawing system includes a first-stage drawing system and a second-stage drawing system arranged sequentially along the drawing direction; the drawing and orientation includes: firstly, the oiled nascent fibers are drawn in the first-stage drawing system at a temperature of 100~120℃ and a draw ratio of 3~4 times, followed by second-stage drawing in the second-stage drawing system at a temperature of 125~140℃ and a draw ratio of 1.2~1.5 times.

[0030] Optionally, in step S1, the intrinsic viscosity of the hydrophilic antistatic PET copolyester chips placed in the vacuum drum drying oven is 0.67~0.78 dL / g, and the mass content of the functional polyester polyols embedded in the hydrophilic antistatic PET copolyester chips is 15wt%~35wt%.

[0031] Optionally, in step S6, the high-moisture-absorbing and antistatic PET copolyester fiber based on polyester polyol obtained by drawing and orientation is a 75D / 36F filament; the 75D / 36F filament has a breaking strength of 3.6~4.0 cN / dtex, a breaking elongation of 21%~32%, a moisture regain of 0.7%~1.2%, and a volume resistivity of 1.810. 6 ~2.310 7 cm.

[0032] According to another aspect of the present invention, a fabric preparation method is also provided, comprising plain weaving the polyester polyol-based high moisture-absorbing and antistatic PET copolyester fiber obtained by the preparation method of polyester polyol high moisture-absorbing and antistatic PET copolyester fiber on a loom, and dyeing the woven fabric to obtain a durable antistatic fabric.

[0033] Optionally, durable antistatic fabrics made from polyester polyol-based highly hygroscopic and antistatic PET copolyester fibers can achieve an electrostatic half-life of <1s before and after washing, which meets the requirements of GB / T 00A012703.1-2008 Evaluation of Electrostatic Properties of Textiles - Determination of Durable Antistatic Textiles.

[0034] Optionally, based on polyester polyol-based hygroscopic and antistatic PET copolyester fibers, the preparation process includes the following steps: self-synthesized hygroscopic and antistatic PET copolyester chips are placed in a vacuum drum drying oven, thoroughly dried, and then fed to the spinning machine feed hopper. The fibers undergo screw extrusion melting, metering pump metering, spinneret extrusion, multi-stage air-temperature ring blowing cooling and forming, bundling and oiling, multi-stage drawing, inspection, and grading and packaging to obtain recycled fine denier PET copolyester fibers with stable thermodynamic properties, high moisture regain, and good elasticity. Furthermore, through the development of key cooling processes and optimization of processing parameters in melt spinning, high moisture regain and antistatic functional PET copolyester fibers are prepared. Moreover, the spinning method provided by this invention has high production efficiency, excellent environmental friendliness, low processing cost, and can be mass-produced. The fabrics woven from these fibers still possess excellent durable antistatic effects, filling the current gap in the industrial production of intrinsically antistatic fibers.

[0035] Example 3 Optionally, 3 kg of hydrophilic antistatic copolyester chips with an intrinsic viscosity of 0.67 dL / g and a polyester polyol content of 15 wt% were placed in a vacuum drum drying oven and dried for 36 hours at 120°C and 10 Pa. The fully dried sample was then fed into a spinning machine feed hopper, where it underwent screw extrusion melting, metering pump metering, spinneret extrusion, multi-stage air-cooling and shaping, bundling and oiling, multi-stage drawing, inspection, grading, and packaging to obtain 78 dtex / 36F PET copolyester fibers. These fibers had a moisture regain of 0.8%, a breaking strength of 3.8 cN / dtex, a breaking elongation of 26%, a fiber volume resistivity of 2.3107 cm⁻¹, and a post-wash electrostatic half-life of 1.8 s for the resulting fabric.

[0036] Optionally, the key spinning process parameters in Example 3 are set as follows: Screw temperature: Zone I temperature is 220℃; Zone II temperature is 240℃; Zone III temperature is 260℃; Zone IV temperature is 270℃. Two-stage drafting process parameters: Stage I drafting system: temperature is 125℃, drafting ratio is 3 times; Stage II drafting system: temperature is 140℃, drafting ratio is 1.3 times.

[0037] Example 4 Optionally, 3 kg of hydrophilic antistatic PET copolyester chips with an intrinsic viscosity of 0.72 dL / g and a polyester polyol content of 25 wt% were placed in a vacuum drum drying oven and dried for 36 hours at 120°C and 10 Pa. The fully dried sample was then fed into a spinning machine feed hopper, where it underwent screw extrusion melting, metering pump metering, spinneret extrusion, multi-stage air-cooling and shaping, bundling and oiling, multi-stage stretching, inspection, grading, and packaging to obtain PET copolyester fibers with a specification of 59 dtex / 36F. The fibers exhibited a moisture regain of 0.8%, a breaking strength of 3.7 cN / dtex, a breaking elongation of 253.5 × 107 cm, and a post-wash electrostatic half-life of 1.1 s for the resulting fabric.

[0038] Optionally, the key spinning process parameters in Example 4 are set as follows: Screw temperature: Zone I temperature is 220℃; Zone II temperature is 240℃; Zone III temperature is 260℃; Zone IV temperature is 270℃. Two-stage drafting process parameters: Stage I drafting system: temperature is 125℃, drafting ratio is 4 times; Stage II drafting system: temperature is 140℃, drafting ratio is 1.4 times.

[0039] Example 5 Optionally, 3 kg of hydrophilic antistatic PET copolyester chips with an intrinsic viscosity of 0.70 dL / g and a polyester polyol content of 35 wt% were placed in a vacuum drum drying oven and dried for 36 hours at 120°C and 10 Pa. The fully dried sample was then fed into a spinning machine feed hopper, where it underwent screw extrusion melting, metering pump metering, spinneret extrusion, multi-stage air-cooling and shaping, bundling and oiling, multi-stage stretching, inspection, grading, and packaging to obtain 64 dtex / 36F PET copolyester fibers with a moisture regain of 0.8%, a breaking strength of 3.8 cN / dtex, a breaking elongation of 21%, a volume resistivity of 2.9106 cm⁻¹, and a post-wash electrostatic half-life of 0.9 s for the resulting fabric.

[0040] Optionally, the key spinning process parameters in Example 5 are set as follows: Screw temperature: Zone I temperature is 220℃; Zone II temperature is 240℃; Zone III temperature is 260℃; Zone IV temperature is 270℃. Two-stage drafting process parameters: Stage I drafting system: temperature is 125℃, drafting ratio is 4 times; Stage II drafting system: temperature is 140℃, drafting ratio is 1.3 times.

[0041] Example 6 Optionally, 3 kg of hydrophilic antistatic PET copolyester chips with an intrinsic viscosity of 0.78 dL / g and a polyester polyol content of 15 wt% are placed in a vacuum drum drying oven and dried for 36 hours at 120°C and 10 Pa. The fully dried sample is then fed into a spinning machine feed hopper, where it undergoes screw extrusion melting, metering pump metering, spinneret extrusion, multi-stage air-cooling and shaping, bundling and oiling, multi-stage stretching, inspection, grading, and packaging to obtain PET copolyester fibers with a specification of 46 dtex / 36F. These fibers have a moisture regain of 0.8%, a breaking strength of 4.0 cN / dtex, a breaking elongation of 22%, a volume resistivity of 2.6 × 10⁶ cm⁻¹, and a post-wash electrostatic half-life of 1.4 s for the resulting fabric.

[0042] Optionally, the key spinning process parameters in Example 6 are set as follows: Screw temperature: Zone I temperature is 220℃; Zone II temperature is 240℃; Zone III temperature is 260℃; Zone IV temperature is 270℃. Two-stage drafting process parameters: Stage I drafting system: temperature is 125℃, drafting ratio is 3 times; Stage II drafting system: temperature is 140℃, drafting ratio is 1.5 times.

[0043] Example 7 Optionally, 3 kg of hydrophilic antistatic PET copolyester chips with an intrinsic viscosity of 0.77 dL / g and a polyester polyol content of 25 wt% were placed in a vacuum drum drying oven and dried for 36 hours at a temperature of 120℃ and a pressure of 10 Pa. The fully dried sample was then fed into the feed hopper of a spinning machine, where it underwent screw extrusion melting, metering pump metering, spinneret extrusion, multi-stage air-cooling and shaping, bundling and oiling, multi-stage stretching, inspection, grading, and packaging to obtain PET copolyester fibers with a specification of 39 dtex / 36F. These fibers had a moisture regain of 0.8%, a breaking strength of 3.6 cN / dtex, a breaking elongation of 32%, a volume resistivity of 1.8106 cm⁻¹, and a static half-life of 1.0 s after washing.

[0044] Optionally, the key spinning process parameters in Example 7 are set as follows: Screw temperature: Zone I temperature is 220℃; Zone II temperature is 240℃; Zone III temperature is 260℃; Zone IV temperature is 270℃. Two-stage drafting process parameters: Stage I drafting system: temperature is 125℃, drafting ratio is 4 times; Stage II drafting system: temperature is 140℃, drafting ratio is 1.5 times.

[0045] Optionally, the durable antistatic polyester fiber in this embodiment of the invention permanently embeds hydrophilic and antistatic groups into the PET macromolecular backbone in the form of chemical bonds through a copolymer structure, thereby ensuring long-lasting function, washability and no degradation; at the same time, this technical solution is compatible with mature melt spinning process, suitable for mass production, and does not sacrifice the mechanical properties and dyeing properties of the fiber.

[0046] Optionally, in this embodiment of the invention, a block copolymer chip is synthesized by embedding ether-bonded polyester polyols as functional monomers into the PET macromolecular chain. This is combined with a multi-stage temperature-controlled melt spinning and plain weaving process. During the polymerization stage, a block copolymer microstructure is constructed, consisting of a first type of repeating unit composed of terephthaloyl residues and aliphatic diol residues, and a second type of repeating unit composed of ether-bonded diol residues. This allows hydrophilic and antistatic groups to be permanently anchored to the polymer backbone via covalent bonds. This is further enhanced by a step-by-step crystallization drying under 10Pa vacuum conditions, a four-zone gradient temperature-controlled screw extrusion melting process (200-270℃), precise metering extrusion, multi-stage air-temperature ring blowing cooling and shaping, and a two-stage gradient temperature control process (100-140℃). Optimized melt spinning processes, including multi-stage drafting and orientation, followed by plain weaving and dyeing, achieve intrinsic and durable moisture absorption and antistatic properties in the PET macromolecular chains without compromising their original regularity, crystallinity, and orientation. This completely avoids the shortcomings of traditional surface coating methods, such as easy washing away of functional properties, and physical blending methods, such as significant decrease in fiber strength due to poor interfacial compatibility. It ensures that the fibers maintain excellent mechanical properties while possessing high moisture regain and low volume resistivity, and imparts excellent antistatic half-life to the fabric. This results in the fabric with a breaking strength of 3.6–4.0 cN / dtex, a breaking elongation of 21%–32%, a moisture regain of 0.7%–1.2%, and a volume resistivity as low as 1.810. 6 ~2.310 7 The intrinsic moisture-wicking and antistatic PET copolyester filament of cm, and the durable antistatic fabric woven from it has a static half-life of less than 1 second before and after washing. It has the technical effect of combining excellent mechanical properties, washability and long-lasting antistatic function, thus solving the technical problems of poor moisture-wicking and antistatic effect and poor fiber mechanical properties of polyester fibers in the prior art.

[0047] Optionally, the technical solution of this invention, through synergistic innovation in molecular structure design and polymerization process, introduces polyester polyol segments containing ether bonds into the main chain of polyethylene terephthalate macromolecules via chemical bonding, constructing a block copolymer system that combines hydrophilic antistatic properties with mechanical stability. This invention not only achieves permanent anchoring of functional groups at the molecular level, avoiding inherent defects such as easy migration of functional components, poor wash resistance, and poor interfacial compatibility in traditional physical addition or surface coating processes, but also effectively controls the crystallization behavior and orientation structure of the copolyester by optimizing key process parameters such as vacuum crystallization drying, multi-stage temperature-controlled melt spinning, and gradient drawing and orientation. This allows the resulting fibers to maintain high breaking strength and suitable elongation while significantly improving moisture regain and greatly reducing volume resistivity, thereby simultaneously achieving a balance between hygroscopicity, antistatic properties, and mechanical properties at the intrinsic performance level, as well as high performance of functional polyester fibers.

[0048] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0049] In the above embodiments of the present invention, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0050] It should be noted that the above embodiments are only used to illustrate the technical concept and implementation effects of the present invention, and are not intended to limit the scope of protection of the present invention. Those skilled in the art can make reasonable adjustments and equivalent substitutions to the type and content of polyester polyols, the ratio of comonomers, spinning process conditions, and fabric structure according to actual needs, without departing from the essential spirit and scope of the present invention. Such changes should still be covered within the scope of protection defined by the claims of the present invention. The molecular design strategy and process control principles disclosed in this invention can also provide useful reference for the development of other functional polyester materials, and have broad technical extensibility and industrial guiding significance.

[0051] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A highly hygroscopic and antistatic PET copolyester fiber based on polyester polyol, characterized in that, The PET copolyester fiber is a filament prepared by melt spinning of hydrophilic and antistatic PET copolyester chips. The hydrophilic and antistatic PET copolyester chips are obtained by copolymerizing functional polyester polyols as functional additive monomers embedded in the PET macromolecular chain. The PET copolyester fiber is an intrinsically hygroscopic and antistatic fiber and is used to process it into durable antistatic fabrics.

2. The PET copolyester fiber based on polyester polyol with high moisture absorption and antistatic properties according to claim 1, characterized in that, The hydrophilic antistatic PET copolyester chips are polymers obtained by block copolymerization of two different types of alcohols. The structure of the polymer includes: a first type of repeating unit composed of terephthaloyl residues and aliphatic diol residues -O-(CH2). p The aliphatic diol is composed of -O-, selected from ethylene glycol, 1,3-propanediol, and 1,4-butanediol, corresponding to form polyethylene terephthalate segments, propylene terephthalate segments, and butylene terephthalate segments. The first type of repeating unit is repeated x times. The second type of repeating unit is composed of a terephthaloyl residue and an ether-bonded diol residue -O-(CH2). a The structure is -O-(CH2)-O-, wherein the ether-containing diol residues are derived from one or more polyester polyols in the ether-containing series, corresponding to the formation of polyethylene terephthalate segments, polyethylene terephthalate segments, and polyethylene terephthalate segments, wherein the number of repetitions of the second type of repeating unit is y; wherein x and y are positive integers.

3. The high moisture absorption and antistatic PET copolyester fiber based on polyester polyol according to claim 2, characterized in that, The polyester polyol containing ether bonds is polyethylene glycol.

4. A method for preparing highly hygroscopic and antistatic PET copolyester fibers based on polyester polyols as described in any one of claims 1 to 3, characterized in that, include: Step S1: The hydrophilic antistatic PET copolyester chips are placed in a vacuum drum drying oven for crystallization drying. After the hydrophilic antistatic PET copolyester chips are fully dried, they are conveyed to the feed hopper of the spinning machine. In step S2, the hydrophilic antistatic PET copolyester chips are fed into the screw extruder through the feed hopper. The screw extruder extrudes and heats the hydrophilic antistatic PET copolyester chips to melt them and form a copolyester melt. Step S3: The copolyester melt is precisely metered by a metering pump and then extruded through a spinneret to form nascent fibers. Step S4: The nascent fibers are cooled and shaped by multi-stage air-temperature circulation, so that the nascent fibers are solidified and formed. Step S5: Bundle the cooled and shaped nascent fibers and apply an oiling treatment to the bundled nascent fibers. Step S6: The oiled nascent fibers are stretched and oriented through a multi-stage stretching system to obtain high moisture absorption and antistatic PET copolyester fibers based on polyester polyols. Step S7: Inspect the PET copolyester fiber based on polyester polyol with high moisture absorption and antistatic properties, and grade it according to the inspection results to obtain the finished fiber.

5. The method for preparing high-moisture-absorbing and antistatic PET copolyester fiber based on polyester polyol according to claim 4, characterized in that, In step S1, the crystallization drying process is carried out under vacuum conditions, and the vacuum pressure inside the vacuum drum drying oven is 10 Pa. The crystallization drying process specifically includes: first, crystallizing the hydrophilic antistatic PET copolyester chips at a crystallization temperature of 90~100℃ for 2~3 hours, and then drying them at a drying temperature of 115~120℃ for 36~48 hours, so that the hydrophilic antistatic PET copolyester chips are fully dried.

6. The method for preparing high-moisture-absorbing and antistatic PET copolyester fibers based on polyester polyols according to claim 4, characterized in that, In step S2, the screw extruder is divided into four temperature control zones along the material conveying direction. The extrusion heating is completed by temperature control in the four temperature control zones, and the temperature ranges of each temperature control zone are as follows: Zone I temperature is 200~220℃, Zone II temperature is 220~240℃, Zone III temperature is 240~260℃, and Zone IV temperature is 240~270℃.

7. The method for preparing high-moisture-absorbing and antistatic PET copolyester fiber based on polyester polyol according to claim 4, characterized in that, In step S6, the multi-stage drawing system includes a first-stage drawing system and a second-stage drawing system arranged sequentially along the drawing direction; the drawing orientation includes: firstly, the oiled nascent fiber is drawn in the first-stage drawing system at a temperature of 100~120℃ and a drawing ratio of 3~4 times, and then drawn in the second-stage drawing system at a temperature of 125~140℃ and a drawing ratio of 1.2~1.5 times, and then drawn in the second-stage drawing system.

8. The method for preparing high-moisture-absorbing and antistatic PET copolyester fiber based on polyester polyol according to claim 4, characterized in that, In step S1, the intrinsic viscosity of the hydrophilic antistatic PET copolyester chips placed in the vacuum drum drying oven is 0.67~0.78 dL / g, and the mass content of the functional polyester polyol embedded in the hydrophilic antistatic PET copolyester chips is 15wt%~35wt%.

9. The method for preparing high-moisture-absorbing and antistatic PET copolyester fiber based on polyester polyol according to claim 4, characterized in that, In step S6, the high-moisture-absorbing and antistatic PET copolyester fiber based on polyester polyol obtained by the stretching and orientation is a 75D / 36F filament; the 75D / 36F filament has a breaking strength of 3.6~4.0 cN / dtex, a breaking elongation of 21%~32%, a moisture regain of 0.7%~1.2%, and a volume resistivity of 1.

810. 6 ~2.310 7 cm.

10. A method for preparing a fabric, characterized in that, The method involves preparing the polyester polyol-based high moisture-absorbing and antistatic PET copolyester fiber according to claim 9 by plain weaving the fiber on a loom and dyeing the resulting fabric to obtain the durable antistatic fabric.

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