Liquid crystal polyarylester fiber treating agent as well as preparation method and application thereof

Abstract

The invention relates to the technical field of fiber treatment agents, in particular to a liquid crystal polyarylester fiber treatment agent and a preparation method and application thereof.The liquid crystal polyarylester fiber treatment agent comprises a component A and a component B. The component A comprises, by weight, 0.1-3 parts of a bundling agent, 0.1-3 parts of a dispersing agent and 94.0-99.8 parts of deionized water; and the component B comprises the following components in parts by weight: 0.1-3 parts of an isolating agent, 0.1-3 parts of a dispersing agent and 94.0-99.8 parts of deionized water. The treating agent is applied to a liquid crystal polyarylester melt spinning process, a component A is firstly applied to liquid crystal polyarylester fibers, then a component B is applied to the liquid crystal polyarylester fibers, and the oiling rate of the liquid crystal polyarylester fibers is 0.5-1.4%. The treating agent can improve the wear resistance of the liquid crystal polyarylate fibers, so that the problems of static electricity and broken filaments caused by friction in the spinning stage are reduced, the fuzzing phenomenon in the downstream warping weaving process is reduced, and the processability of the fibers is effectively improved.

Description

Technical Field

[0001] This invention relates to a liquid crystal polyarylate fiber treatment agent, its preparation method and application, belonging to the technical field of fiber treatment agents. Background Technology

[0002] Liquid crystal polyarylates are typically obtained from aromatic monomers with hydroxyl and carboxyl functional groups through acetylation and polycondensation reactions. They possess both the high strength and high modulus properties common to general polyarylates, as well as unique liquid crystal properties. Thermotropic liquid crystal polyarylate fibers are fiber materials with excellent comprehensive properties, including high strength, high elasticity, resistance to bending and abrasion, resistance to chemical reagents, low moisture absorption, and strong dimensional stability. They are used in aerospace, marine materials, electrical and electronic equipment, ropes and cables, and personal protective equipment.

[0003] Liquid crystal polyaryl ester (LCP) fibers are prepared by melt spinning. Liquid crystal polyaryl ester chips are heated and melted, then extruded from the spinneret to form a new fiber. After cooling and solidification, the fiber is stretched by a winding device to obtain a nascent fiber. The nascent fiber does not require thermal stretching treatment. Instead, it is subjected to high-temperature long-term static / dynamic heat treatment to promote the reaction of carboxyl and acetyl groups at the end of the molecular chain in the amorphous region, thereby increasing the molecular weight and improving the fiber performance.

[0004] Liquid crystal polyaryl ester (LCP) fiber treatment agents primarily address issues related to fiber production, molding, processing, and subsequent material composite applications. During melt spinning, LCP fibers exhibit high spinning speeds (400-1200 m / min), resulting in dry fibers and continuous friction with metal rollers, leading to severe static electricity. This causes loose fiber bundles, uneven tension distribution, and a tendency for fuzz and breakage. In subsequent heat treatment, unlike other high-performance fibers, LCP fibers undergo high solid-state polycondensation at long temperatures (240-280 ℃, approximately 20 h). Conventional treatment agent components easily decompose or volatilize, failing to effectively isolate the fibers and causing them to stick together and harden after treatment. Furthermore, unvolatile components in conventional treatment agents are prone to coking during prolonged heat treatment, leading to a decrease in fiber strength. In downstream applications, the warping and weaving processes involve significant friction, making LCP fibers highly susceptible to fuzz formation and reducing fiber performance.

[0005] Patent application WO2024179608A1 discloses a method for treating LCP fibers. During the spinning stage, an aqueous solution of alkyl phosphate salt is sprayed, which reacts with the amide groups of LCP to form hydrogen bonds, enhancing the bonding between the treatment agent and the LCP fibers and improving the bonding between LCP fibers and other resins. Similarly, patent application CN120649198A discloses a treatment process using phosphate salts and silicone oil with specific chain lengths to suppress static electricity generated by high-speed spinning and fiber adhesion caused by subsequent processing. Both methods use phosphate salts as the core treatment agent, which can reduce static electricity generation and improve the bonding with resins to some extent. However, phosphate salts partially decompose at high temperatures, and components such as silicone oil cannot withstand prolonged high-temperature treatment, resulting in volatilization and decomposition.

[0006] Therefore, developing high-quality, adaptable LCP fiber forming and processing agents plays an important role in promoting the synchronous development of LCP fibers. Summary of the Invention

[0007] This invention addresses the shortcomings of existing technologies by providing a liquid crystal polyarylate fiber treatment agent, its preparation method, and its application. The treatment agent improves the abrasion resistance of liquid crystal polyarylate fibers, thereby reducing static electricity and fuzzing issues caused by friction during the spinning stage and reducing pilling during downstream warping and weaving processes. Furthermore, it provides effective inter-filament isolation and exhibits no adverse reaction with the fibers at high temperatures, preventing adhesion and hardening problems after solid-phase polycondensation of the liquid crystal polyarylate fibers, thus effectively improving fiber processability.

[0008] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: a liquid crystal polyarylate fiber treatment agent, the treatment agent comprising component A and component B, wherein, by weight, component A comprises 0.1-3 parts of a bundler, 0.1-3 parts of a dispersant, and 94.0-99.8 parts of deionized water; Component B, by weight, comprises 0.1-3 parts of release agent, 0.1-3 parts of dispersant, and 94.0-99.8 parts of deionized water.

[0009] Furthermore, the slugging agent is at least one of hydrated aluminum silicate and polyethylene oxide.

[0010] Furthermore, the separating agent is at least one of talc, colloidal silica, hexagonal boron nitride, and mica.

[0011] Furthermore, the dispersant is sodium hexametaphosphate.

[0012] Furthermore, component A has a pH value of 6.0-9.0, a solid content of 0.2-6%, and a viscosity of 1-7 cp at 25°C. The pH value of component B is 6.0-9.0, the solid content is 0.2-6%, and the viscosity at 25°C is 1-7 cp.

[0013] Furthermore, the particle size D99 of the slugging agent is 1-10 μm, and when the slugging agent is polyethylene oxide, the weight-average molecular weight of the polyethylene oxide is 500,000-1,000,000. The particle size D99 of the release agent is 2-10 μm.

[0014] Furthermore, the particle size D99 of the clustering agent is smaller than the particle size D99 of the release agent.

[0015] This invention also discloses a method for preparing a liquid crystal polyarylate fiber treatment agent, wherein the preparation method is as follows: Preparation of Component A: Add the bridging agent and dispersant to deionized water in proportion, stir and mix thoroughly, grind and filter to obtain Component A; Preparation of Component B: The separating agent and dispersant are added to deionized water in proportion, stirred and mixed thoroughly, then ground and filtered to obtain Component B.

[0016] Furthermore, during the preparation of component A, the zirconium beads used in the grinding process were 0.2 mm in size, and the grinding time was 1-1.5 h. During the preparation of component B, the zirconium beads used in the grinding process were 0.4 mm in size, and the grinding time was 1-1.5 h.

[0017] The present invention also discloses the application of a liquid crystal polyarylate fiber treatment agent, wherein the treatment agent is applied to the liquid crystal polyarylate melt spinning process, wherein component A is first applied to the liquid crystal polyarylate fiber and then component B is applied, and the oiling rate of the liquid crystal polyarylate fiber is 0.5-1.4%.

[0018] The beneficial effects of this invention are: Compared with traditional treatment agents, the liquid crystal polyarylate fiber treatment agent of this invention uses a combination of inorganic substances with very strong thermal stability. Compared with conventional oil-phase liquid treatment agents, it has higher thermal stability and basically no volatilization or decomposition during high temperature and long-term post-treatment. The effective components are more stable, reducing the functional reduction caused by thermal volatilization and decomposition of the treatment agent, the increase of side reactions with the fiber, and the loss and waste of the treatment agent itself.

[0019] The liquid crystal polyarylate fiber treatment agent of the present invention has good spreading uniformity and continuity on the surface of liquid crystal polyarylate fiber, resulting in significant wear resistance. It avoids static electricity and fuzzing problems caused by friction during high-speed spinning and downstream warping and weaving, and reduces fuzzing during the downstream warping and weaving process.

[0020] This invention, by controlling the particle size and morphology of the treatment agent, achieves high adsorption and continuous, uniform spreading of liquid crystal polyarylate fibers. Furthermore, through its surface charge characteristics, it generates a strong interaction with the liquid crystal polyarylate fibers, thus fully exerting its isolating effect during prolonged heat treatment. Moreover, it exhibits no adverse reactions with the fibers at high temperatures, preventing adhesion and hardening problems that occur after solid-phase polycondensation of the liquid crystal polyarylate fibers. The treatment agent of this invention can prevent adhesion between monofilaments of the liquid crystal polyarylate fibers and improve fiber softness, effectively enhancing fiber processability.

[0021] The liquid crystal polyarylate fiber treatment agent of this invention can achieve significant effects with a small application amount, and it does not contain any silicone oil-based substances, thus having minimal impact on downstream material composites. Furthermore, the components of the treatment agent described in this invention remain stable for extended periods at 300 °C and exhibit reactive inertness with LCP fibers under the same conditions. Attached Figure Description

[0022] Figure 1 Scanning electron microscope image of liquid crystal polyarylate fiber without treatment agent; Figure 2 This is a scanning electron microscope image of liquid crystal polyarylate fibers after treatment with the treatment agent of Example 1. Detailed Implementation

[0023] The specific embodiments of the present invention will be described in detail below. The present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed.

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used is for describing particular embodiments only and is not intended to limit the invention.

[0025] A liquid crystal polyarylate fiber treatment agent, the treatment agent comprising component A and component B, wherein component A comprises 0.1-3 parts of a bundler, 0.1-3 parts of a dispersant, and 94.0-99.8 parts of deionized water by weight; Component B, by weight, comprises 0.1-3 parts of release agent, 0.1-3 parts of dispersant, and 94.0-99.8 parts of deionized water.

[0026] Specifically, the slugging agent is at least one of hydrated aluminum silicate and polyethylene oxide.

[0027] Specifically, the separating agent is at least one of talc, colloidal silica, hexagonal boron nitride, and mica.

[0028] Specifically, the dispersant is sodium hexametaphosphate.

[0029] Specifically, component A has a pH value of 6.0-9.0, a solid content of 0.2-6%, and a viscosity of 1-7 cp at 25°C. The pH value of component B is 6.0-9.0, the solid content is 0.2-6%, and the viscosity at 25°C is 1-7 cp.

[0030] Specifically, the particle size D99 of the slugging agent is 1-10 μm, and when the slugging agent is polyethylene oxide, the weight-average molecular weight of polyethylene oxide is 500,000-1,000,000. The particle size D99 of the release agent is 2-10 μm.

[0031] Preferably, the particle size D99 of the slugging agent is 1-2 μm, and when the slugging agent is polyethylene oxide, the weight-average molecular weight of the polyethylene oxide is 500,000-750,000. The particle size D99 of the release agent is 2-5 μm.

[0032] Specifically, the particle size D99 of the clustering agent is smaller than the particle size D99 of the separating agent.

[0033] This invention also discloses a method for preparing a liquid crystal polyarylate fiber treatment agent, wherein the preparation method is as follows: Preparation of Component A: Add the bridging agent and dispersant to deionized water in proportion, stir and mix thoroughly, grind and filter to obtain Component A; Preparation of Component B: The separating agent and dispersant are added to deionized water in proportion, stirred and mixed thoroughly, then ground and filtered to obtain Component B.

[0034] Specifically, in the preparation of component A, the zirconium beads used in the grinding process are 0.2 mm in size, the main machine speed is 2500 rpm, and the grinding time is 1-1.5 h; the filter membrane used for filtration has an accuracy of 1-2 microns, and the final particle size is controlled by controlling the grinding time.

[0035] In the preparation of component B, the zirconium beads used in the grinding process were 0.4 mm in size, the main machine speed was 2500 rpm, the grinding time was 1-1.5 h, and the filter membrane used for filtration had an accuracy of 4-5 microns. The final particle size was controlled by controlling the grinding time.

[0036] The present invention also discloses the application of a liquid crystal polyarylate fiber treatment agent. The treatment agent is applied to the liquid crystal polyarylate melt spinning process. The treatment agent is applied to the fiber by means of an oil nozzle. The application temperature is room temperature. The oiling rate is controlled by adjusting the frequency of the oil pump. Component A is applied to the liquid crystal polyarylate fiber first, and then component B is applied. The oiling rate of the liquid crystal polyarylate fiber is 0.5-1.4%.

[0037] The liquid crystal polyaryl ester fiber treatment agent is applied to 100-500D liquid crystal polyaryl ester fibers, wherein the liquid crystal polyaryl ester fibers have a tensile strength ≥22 cN / dtex, an elastic modulus ≥90 GPa, and an elongation of 3.0-4.0%.

[0038] More specifically, the information on the raw material suppliers involved in the embodiments of the present invention is as follows: Hydrated aluminum silicate: Products from Xi'an Tianzheng Pharmaceutical Excipients Co., Ltd. are used; Polyethylene oxide: Products selected from Hubei Shiteng Chemical Technology Co., Ltd.; Talc powder: Products from Liaoning Ribang Nanotechnology Co., Ltd.; Colloidal silica: purchased from Shijiazhuang Fengming Mineral Products Co., Ltd.; Hexagonal boron nitride: purchased from Yumu New Materials Co., Ltd.; Mica: Purchased from Yuexin Mica Factory; Sodium hexametaphosphate: purchased from Weifang Ruier Chemical Co., Ltd.; The above-mentioned raw materials do not constitute a limitation on the technical solution of this invention.

[0039] I. Examples and Comparative Examples of LCP Fiber Treatment Agent Preparation Example 1 The formulation composition of the liquid crystal polyarylate fiber treatment agent in this embodiment is shown in Table 1 below: Table 1. Formulation composition of liquid crystal polyarylate fiber treatment agent in Example 1

[0040] The preparation process includes the following steps: Step 1: Add the clustering agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component A. The stirring rate is 800 rpm, the stirring time is 2 h, the zirconium bead size in the horizontal sand mill is 0.2 mm, the grinding time is 1 h, and the filter membrane used for filtration has a precision of 2 micrometers. Step 2: Add the separating agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component B. The stirring rate is 800 rpm, the stirring time is 2 hours, the zirconium bead size in the horizontal sand mill is 0.4 mm, the grinding time is 1 hour, and the filter membrane used for filtration has a precision of 5 micrometers. The liquid crystal polyarylate fiber treatment agent prepared in this embodiment includes two separate components, A and B, both of which are milky white opaque liquids.

[0041] Example 2 The formulation composition of the liquid crystal polyarylate fiber treatment agent in this embodiment is shown in Table 2 below: Table 2. Formulation composition of liquid crystal polyarylate fiber treatment agent in Example 2

[0042] Based on Example 1, the bridging agent in Example 2 was replaced with hydrated aluminum silicate, while all other aspects were the same as in Example 1.

[0043] The preparation process includes the following steps: Step 1: Add the clustering agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component A. The stirring rate is 800 rpm, the stirring time is 2 h, the zirconium bead size in the horizontal sand mill is 0.2 mm, the grinding time is 1 h, and the filter membrane used for filtration has a precision of 2 micrometers. Step 2: Add the separating agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component B. The stirring rate is 800 rpm, the stirring time is 2 hours, the zirconium bead size in the horizontal sand mill is 0.4 mm, the grinding time is 1 hour, and the filter membrane used for filtration has a precision of 5 micrometers. The liquid crystal polyarylate fiber treatment agent prepared in this embodiment includes two separate components, A and B, both of which are milky white opaque liquids.

[0044] Example 3 The formulation composition of the liquid crystal polyarylate fiber treatment agent in this embodiment is shown in Table 3 below: Table 3. Formulation composition of liquid crystal polyarylate fiber treatment agent in Example 3

[0045] Based on Example 1, the release agent in Example 3 was replaced with hexagonal boron nitride instead of talc, and all other aspects were the same as in Example 1.

[0046] The preparation process includes the following steps: Step 1: Add the clustering agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component A. The stirring rate is 800 rpm, the stirring time is 2 h, the zirconium bead size in the horizontal sand mill is 0.2 mm, the grinding time is 1 h, and the filter membrane used for filtration has a precision of 2 micrometers. Step 2: Add the separating agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component B. The stirring rate is 800 rpm, the stirring time is 2 hours, the zirconium bead size in the horizontal sand mill is 0.4 mm, the grinding time is 1 hour, and the filter membrane used for filtration has a precision of 5 micrometers. The liquid crystal polyarylate fiber treatment agent prepared in this embodiment includes two separate components, A and B, both of which are milky white opaque liquids.

[0047] Example 4 The formulation composition of the liquid crystal polyarylate fiber treatment agent in this embodiment is shown in Table 4 below: Table 4. Formulation composition of liquid crystal polyarylate fiber treatment agent in Example 4

[0048] Based on Example 1, the proportions of the bridging agent and dispersant in component A of Example 4 are increased, while the rest are the same as in Example 1.

[0049] The preparation process includes the following steps: Step 1: Add the clustering agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component A. The stirring rate is 800 rpm, the stirring time is 2 h, the zirconium bead size in the horizontal sand mill is 0.2 mm, the grinding time is 1 h, and the filter membrane used for filtration has a precision of 2 micrometers. Step 2: Add the separating agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component B. The stirring rate is 800 rpm, the stirring time is 2 hours, the zirconium bead size in the horizontal sand mill is 0.4 mm, the grinding time is 1 hour, and the filter membrane used for filtration has a precision of 5 micrometers. The liquid crystal polyarylate fiber treatment agent prepared in this embodiment includes two separate components, A and B, both of which are milky white opaque liquids.

[0050] Example 5 The formulation composition of the liquid crystal polyarylate fiber treatment agent in this embodiment is shown in Table 5 below: Table 5. Formulation composition of the liquid crystal polyarylate fiber treatment agent in Example 5

[0051] Based on Example 1, the particle size of the bridging agent and dispersant in component A of Example 5 is reduced, while the rest are the same as in Example 1.

[0052] The preparation process includes the following steps: Step 1: Add the clustering agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component A. The stirring rate is 800 rpm, the stirring time is 2 hours, the zirconium bead size in the horizontal sand mill is 0.2 mm, the grinding time is 3 hours, and the filter membrane used for filtration has a precision of 1 micrometer. Step 2: Add the separating agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component B. The stirring rate is 800 rpm, the stirring time is 2 hours, the zirconium bead size in the horizontal sand mill is 0.4 mm, the grinding time is 1 hour, and the filter membrane used for filtration has a precision of 5 micrometers. The liquid crystal polyarylate fiber treatment agent prepared in this embodiment includes two separate components, A and B, both of which are milky white opaque liquids.

[0053] In the above embodiments, the liquid crystal polyarylate fiber treatment agent includes two separate components, A and B, and the application order is to apply component A first and then component B.

[0054] Example 6 The formulation composition of the liquid crystal polyarylate fiber treatment agent in this embodiment is shown in Table 6 below: Table 6. Formulation composition of the liquid crystal polyarylate fiber treatment agent in Example 6 The preparation process includes the following steps: Step 1: Add the flocculating agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component A. The stirring rate is 800 rpm, the stirring time is 2 h, the zirconium bead size in the horizontal sand mill is 0.2 mm, the grinding time is 1 h, and the filter membrane used for filtration has a precision of 2 micrometers. Step 2: Add the release agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component B. The stirring rate is 800 rpm, the stirring time is 2 h, the zirconium bead size in the horizontal sand mill is 0.4 mm, the grinding time is 1 h, and the filter membrane used for filtration has a precision of 5 micrometers. The liquid crystal polyarylate fiber treatment agent prepared in this embodiment includes two separate components, A and B, both of which are milky white opaque liquids.

[0055] Example 7

[0056] The formulation composition of the liquid crystal polyarylate fiber treatment agent in this embodiment is shown in Table 7 below: Table 7. Formulation composition of the liquid crystal polyarylate fiber treatment agent in Example 7 The preparation process includes the following steps: Step 1: Add the clustering agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component A. The stirring rate is 800 rpm, the stirring time is 2 h, the zirconium bead size in the horizontal sand mill is 0.2 mm, the grinding time is 1.5 h, and the filter membrane used for filtration has a precision of 2 micrometers. Step 2: Add the release agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component B. The stirring rate is 800 rpm, the stirring time is 2 h, the zirconium bead size in the horizontal sand mill is 0.4 mm, the grinding time is 1.5 h, and the filter membrane used for filtration has a precision of 5 micrometers. The liquid crystal polyarylate fiber treatment agent prepared in this embodiment includes two separate components, A and B, both of which are milky white opaque liquids.

[0057] Example 8

[0058] The formulation composition of the liquid crystal polyarylate fiber treatment agent in this embodiment is shown in Table 8 below: Table 8. Formulation composition of the liquid crystal polyarylate fiber treatment agent in Example 8 The preparation process includes the following steps: Step 1: Add the clustering agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component A. The stirring rate is 800 rpm, the stirring time is 2 h, the zirconium bead size in the horizontal sand mill is 0.2 mm, the grinding time is 1.5 h, and the filter membrane used for filtration has a precision of 2 micrometers. Step 2: Add the release agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component B. The stirring rate is 800 rpm, the stirring time is 2 h, the zirconium bead size in the horizontal sand mill is 0.4 mm, the grinding time is 1.5 h, and the filter membrane used for filtration has a precision of 5 micrometers. The liquid crystal polyarylate fiber treatment agent prepared in this embodiment includes two separate components, A and B, both of which are milky white opaque liquids.

[0059] Comparative Example 1 The formulation composition of the liquid crystal polyarylate fiber treatment agent in Comparative Example 1 is shown in Table 9 below: Table 9. Composition of the liquid crystal polyarylate fiber treatment agent in Comparative Example 1

[0060] Based on Example 1, the particle size of the isolating agent and dispersant in component B of Comparative Example 1 was reduced, while the application methods of the remaining components and treatment agents were the same as in Example 1.

[0061] The preparation process includes the following steps: Step 1: Add the clustering agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component A. The stirring rate is 800 rpm, the stirring time is 2 h, the zirconium bead size in the horizontal sand mill is 0.4 mm, the grinding time is 1 h, and the filter membrane used for filtration has a precision of 2 micrometers. Step 2: Add the separating agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component B. The stirring rate is 800 rpm, the stirring time is 2 hours, the zirconium bead size in the horizontal sand mill is 0.2 mm, the grinding time is 5 hours, and the filter membrane used for filtration has a precision of 0.5 micrometers. The liquid crystal polyarylate fiber treatment agent prepared in this comparative example includes two separate components, A and B, both of which are milky white opaque liquids.

[0062] Comparative Example 2 The formulation composition of the liquid crystal polyarylate fiber treatment agent in Comparative Example 2 is shown in Table 10 below: Table 10. Formulation composition of liquid crystal polyarylate fiber treatment agent in Comparative Example 2

[0063] Based on Example 1, the particle size of each additive in components A and B of Comparative Example 2 was increased, while the application methods of the remaining components and treatment agents were the same as in Example 1.

[0064] The preparation process includes the following steps: Step 1: Add the bridging agent and dispersant to the aqueous phase in the specified proportions, and mix thoroughly to obtain component A. The stirring speed is 800 rpm, and the stirring time is 2 hours. Step 2: Add the separating agent and dispersant to the aqueous phase in the specified proportions, and mix thoroughly to obtain component B. The stirring speed is 800 rpm, and the stirring time is 2 hours. The liquid crystal polyarylate fiber treatment agent prepared in this comparative example includes two separate components, A and B, both of which are milky white opaque liquids.

[0065] Comparative Example 3 The composition and preparation method of the liquid crystal polyarylate fiber treatment agent in this comparative example are exactly the same as those in Example 1, except for the application method of components A and B. In this comparative example, component B is applied first, followed by component A.

[0066] Comparative Example 4 The composition and preparation method of the liquid crystal polyarylate fiber treatment agent in this comparative example are exactly the same as those in Example 1, except for the preparation and application methods of components A and B.

[0067] The preparation process includes the following steps: Step 1: Add the clustering agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component A. The stirring rate is 800 rpm, the stirring time is 2 h, the zirconium bead size in the horizontal sand mill is 0.2 mm, the grinding time is 1 h, and the filter membrane used for filtration has a precision of 2 micrometers. Step 2: Add the separating agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component B. The stirring rate is 800 rpm, the stirring time is 2 hours, the zirconium bead size in the horizontal sand mill is 0.4 mm, the grinding time is 1 hour, and the filter membrane used for filtration has a precision of 5 micrometers. Step 3: After thoroughly mixing components A and B, the final treatment agent is obtained. The stirring speed is 800 rpm and the stirring time is 2 hours.

[0068] The liquid crystal polyarylate fiber treatment agent prepared in this comparative example is a mixture of components A and B, both of which are milky white opaque liquids.

[0069] Comparative Example 5 The formulation composition of the liquid crystal polyarylate fiber treatment agent in Comparative Example 5 is shown in Table 11 below: Table 11. Formulation composition of liquid crystal polyarylate fiber treatment agent in Comparative Example 5

[0070] Based on Example 1, the particle size of the bridging agent and dispersant in component A of Comparative Example 5 is larger than that of the separating agent and dispersant in component B. The application methods of the remaining components and treatment agents are the same as those in Example 1.

[0071] The preparation process includes the following steps: Step 1: Add the clustering agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component A. The stirring rate is 800 rpm, the stirring time is 2 hours, the zirconium bead size in the horizontal sand mill is 0.4 mm, the grinding time is 1 hour, and the filter membrane used for filtration has a precision of 5 micrometers. Step 2: Add the separating agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component B. The stirring rate is 800 rpm, the stirring time is 2 h, the zirconium bead size in the horizontal sand mill is 0.2 mm, the grinding time is 5 h, and the filter membrane used for filtration has a precision of 2 micrometers. The liquid crystal polyarylate fiber treatment agent prepared in this comparative example includes two separate components, A and B, both of which are milky white opaque liquids.

[0072] Comparative Example 6 The formulation composition of the liquid crystal polyarylate fiber treatment agent in Comparative Example 6 is shown in Table 12 below: Table 12. Formulation composition of liquid crystal polyarylate fiber treatment agent in Comparative Example 6

[0073] Based on Example 1, the proportion of dispersant in components A and B of Comparative Example 6 was increased, while the application methods of the remaining components and treatment agents were the same as in Example 1.

[0074] The preparation process includes the following steps: Step 1: Add the clustering agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component A. The stirring rate is 800 rpm, the stirring time is 2 h, the zirconium bead size in the horizontal sand mill is 0.2 mm, the grinding time is 1 h, and the filter membrane used for filtration has a precision of 2 micrometers. Step 2: Add the separating agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component B. The stirring rate is 800 rpm, the stirring time is 2 hours, the zirconium bead size in the horizontal sand mill is 0.4 mm, the grinding time is 1 hour, and the filter membrane used for filtration has a precision of 5 micrometers. The liquid crystal polyarylate fiber treatment agent prepared in this embodiment includes two separate components, A and B, both of which are milky white opaque liquids.

[0075] Comparative Example 7 The formulation of the liquid crystal polyarylate fiber treatment agent in Comparative Example 7 is the same as that in Example 1, except that the grinding time is extended during the preparation process. The specific preparation steps are as follows: Step 1: Add the clustering agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component A. The stirring rate is 800 rpm, the stirring time is 2 h, the zirconium bead size in the horizontal sand mill is 0.2 mm, the grinding time is 3 h, and the filter membrane used for filtration has a precision of 2 micrometers. Step 2: Add the release agent and dispersant to the aqueous phase in proportion, stir thoroughly to mix evenly, then transfer to a horizontal sand mill for grinding, and filter to obtain component B. The stirring rate is 800 rpm, the stirring time is 2 hours, the zirconium bead size in the horizontal sand mill is 0.4 mm, the grinding time is 3 hours, and the filter membrane used for filtration has a precision of 5 micrometers. The liquid crystal polyarylate fiber treatment agent prepared in this embodiment includes two separate components, A and B, both of which are milky white opaque liquids.

[0076] II. Testing and Evaluation of Physicochemical Performance Indicators The physicochemical properties of the treatment agents in Examples 1-5 and Comparative Examples 1-7 were tested at an ambient temperature of 25°C. The testing instruments are as follows: (1) The density of the sample was tested using a densitometer, which was purchased from Anton Paar, USA, and the model was DMA501; (2) The pH value of the sample was tested using a pH meter, which was purchased from Metrohm, Switzerland, and the model was SD20kit; (3) The viscosity was tested using a rotational viscometer, which was purchased from Anton Paar in the United States and was model ViscoQC 100. (4) The average particle size of the sample was tested using a laser particle size analyzer, model Malvern 3000.

[0077] (5) The stability of the samples was evaluated by standing. 100 mL of the fiber treatment agent of each case was put into a 100 mL glass graduated cylinder with a sealing plug and placed at 30 °C for 1 month. The appearance of the treatment agent was observed immediately after preparation and after 1 month. The evaluation was divided into three categories: stable, slight stratification and precipitation.

[0078] The test results are shown in Table 13: Table 13 Comparison of Physical and Chemical Performance Test Results

[0079] As shown in Table 13, the stability of the treatment agent is related to both the particle size of the components and the mixing method.

[0080] III. Application Status Test of Liquid Crystal Polyarylate Fiber The treatment agents of Examples 1-5 and Comparative Examples 1-7 were applied to LCP fibers, and the fibers were post-treated to prepare finished fibers. The specific applications and fiber preparation processes are as follows.

[0081] Self-made liquid crystal polyarylate chips were used for spinning. The melt was melted in a single-screw extruder and extruded through a spinneret at a melting temperature of 280℃-360℃. A first oil nozzle was placed 0.5 m below the spinneret, and a second oil nozzle was placed 0.75 m below the spinneret. The first and second oil nozzles were individually controlled by their respective oil pumps and oil tanks. In all examples and comparative examples, the circulating amount of treatment agent at the first and second oil nozzles was the same (the oil pump opening was fixed). The fibers passed sequentially through the first and second oil nozzles to obtain fibers with a surface coated with the treatment agent. The total oiling rate was controlled at 0.5-1.4% (the ratio of treatment agent to fiber mass). Specifically, in Examples 1-5 and Comparative Examples 1-2, 5-7, components A and B were applied at the first and second oil nozzles, respectively; in Comparative Example 3, components A and B were applied at the second and first oil nozzles, respectively; in Comparative Example 4, the single treatment agent was applied at the second oil nozzle, and no treatment agent was applied at the first oil nozzle. The treated fibers are wound into a cylinder after passing through two guide discs at a winding speed of 600 m / min, with a fiber specification of 400D / 80f. The nascent fibers are then subjected to static heat treatment at a temperature of 250-270 ℃ for 20 h.

[0082] The relevant indicators were tested and evaluated as follows: (1) The oiling rate was tested by weighing. Untreated finished fibers were dried at 85°C to constant weight and the mass (m1) was recorded. Fibers of equal length treated with the treatment agent were dried to constant weight under the same conditions and the mass (m2) was recorded. Oiling rate = (m2-m1) / m1×100%; (2) The tensile breaking strength of the fiber was tested using an electronic universal testing machine; (3) The bundling performance of the finished fiber was evaluated by the scoring method. The evaluation results were: 3 represents almost no loose fibers, 2 represents a small amount of loose fibers, 1 represents a certain amount of loose fibers, and 0 represents severe fiber bundle separation. (4) The anti-adhesion effect of the treatment agent on the finished fiber is evaluated by the ratio of the total number of monofilaments in the fiber bundle (N, N=80) to the number of monofilaments that can be separated from the fiber bundle (n) (f=N / n). The larger f is, the fewer monofilaments can be separated, that is, the poor anti-adhesion effect. (5) The scoring method is used to evaluate the fiber breakage of the finished product. The evaluation results include: 3 represents almost no fiber breakage; 2 represents a small amount of fiber breakage; 1 represents a certain amount of fiber breakage; 0 represents very serious fiber breakage. (6) The softness of the finished fiber is evaluated by a scoring method. The evaluation results include: 3 represents very soft fiber bundle; 2 represents relatively hard fiber bundle; 1 represents severely hardened fiber bundle; 0 represents completely hardened fiber bundle.

[0083] The evaluation results are shown in Table 14.

[0084] Table 14 Comparison Results of LCP Finished Fiber Application Evaluation Indicators

[0085] As shown in Table 14, the LCP fibers treated with the fiber treatment agent in the embodiments of the present invention have excellent breaking strength, bundle properties, anti-adhesion properties and fiber softness, and the finished fiber has few broken filaments.

[0086] Scanning electron microscope image of liquid crystal polyarylate fiber without treatment agent as shown below Figure 1 As shown, the scanning electron microscope image of the liquid crystal polyarylate fiber after treatment with the treatment agent of Example 1 is as follows. Figure 2 As shown. (Through) Figure 1 and Figure 2 It can be seen that after treatment with the treatment agent of Example 1, the surface treatment agent of liquid crystal polyarylate fiber is evenly coated, and the adhesion between monofilaments and the fuzzing phenomenon are significantly reduced.

[0087] After application to the samples in Examples 1-8, there were few broken filaments, indicating that the treatment agent had a significant abrasion resistance effect, effectively reducing the friction between fibers and between fibers and metals during spinning and post-treatment, thus playing a significant antistatic role, and the fiber bundling effect was excellent; after post-treatment, the filaments could be separated from each other, and the filament bundles were soft, indicating that the treatment agent had a significant anti-adhesion effect; the finished fiber strength reached a high level, indicating that there was no adverse reaction between the treatment agent and the fiber during the long-term heat treatment process.

[0088] After the sample in Example 4 was applied, the fiber's various indicators remained at a relatively good level, indicating that increasing the proportion of bundler and dispersant would not have an adverse effect on the fiber heat treatment.

[0089] After the sample in Example 5 was applied, the fiber indicators remained at a high level, and the fiber strength was further improved. This indicates that reducing the particle size of the bundler (less than 1 μm) is beneficial to forming a basic bond and continuous film on the fiber surface, and may also promote the dispersion of the release agent. Larger release agent particles dispersed on the film layer become the actual support points when the fibers come into contact, effectively suppressing the filament sticking phenomenon caused by long-term heat treatment.

[0090] The data comparison between Comparative Example 1 and Example 1 shows that if the particle size of the release agent is reduced (<0.5 μm), the small release agent particles may be coated in the rough structure formed by the relatively large bundle agent particles, and cannot effectively play the role of release. This leads to severe fiber adhesion and hardening during heat treatment, which in turn affects the escape of small molecules during solid-phase polycondensation and is not conducive to the growth of fiber molecular weight and the improvement of strength.

[0091] A comparison of the data from Comparative Example 2 and Example 1 shows that: if the particle size of the filament-binding agent and the release agent is increased (<20 μm), the large particles of filament-binding agent cannot effectively enter and fill the tiny gaps between the monofilaments, resulting in fewer bonding points, uneven bonding force, and poorer fiber bundle integrity. This makes it easier for fuzz to form during high-speed winding and unwinding, and also reduces the tensile strength of the fiber bundle. Excessively large release agent particles cause changes in the frictional behavior of the fiber, evolving from smooth rolling friction to unstable sliding friction, reducing fiber abrasion resistance and also increasing fuzz during production and application. Due to the increased particle size of the release agent, it may evolve from a layered spreading pattern to a stacked spreading pattern on the fiber surface, affecting the separation effect between the fiber monofilaments, leading to monofilament adhesion during heat treatment, resulting in fiber hardening and inhibiting the improvement of fiber strength. Table 8 shows that due to the increased particle size of the additives, the settling speed is faster, and the stability of the treatment agent system decreases.

[0092] A comparison of the data from Comparative Example 3 and Example 1 shows that if the application method of the treatment agent is changed, i.e., the release agent component B is applied first, followed by the condenser component A, the release agent first occupies the fiber surface sites, forming sparse and discrete attachment points. Subsequently, small condenser particles fill the gaps in the large release agent particles, severely hindering the uniform spreading and film formation of the small condenser particles, resulting in a decrease in the condensation effect, an increase in fiber looseness, and an increased probability of fuzz formation. In addition, the release agent particles may be partially covered and wrapped by the condenser, weakening the fulcrum effect, affecting the isolation between fiber monofilaments, leading to fiber adhesion and hardening during heat treatment, and inhibiting strength improvement.

[0093] The data comparison between Comparative Example 4 and Example 1 shows that if the method of applying the treatment agent is changed, that is, the A-bundling agent component and the B-isolating agent component are mixed evenly and then applied simultaneously, the competitive adsorption phenomenon of the isolating agent and the bundler will occur, and the same problem as in Comparative Example 3 will occur, affecting the abrasion resistance, bundler properties and isolation properties of the fiber, and thus affecting the heat treatment effect of the fiber.

[0094] A comparison of the data from Comparative Example 5 and Example 1 shows that if the particle size D99 of the filament-aggregating agent is larger than that of the release agent, the performance of the oiled liquid crystal polyarylate fiber decreases, and the aggregating properties deteriorate while the number of filaments increases. This is because the relatively small particle size of the filament-aggregating agent allows for a more uniform and continuous coverage of the fiber surface, resulting in high film uniformity and preventing it from becoming a friction point or stress concentration point. Small-particle filament-aggregating agents can better integrate with the microstructure of the fiber surface, improving the aggregating strength. The relatively large particle size of the release agent provides support at the monofilament contact points, effectively preventing the monofilaments from melting and sticking together, resulting in significant physical isolation. The small-particle filament-aggregating agent forms a strong base film, while the relatively large-particle release agent is uniformly embedded within it or distributed on the surface. The filament-aggregating agent ensures the integrity of the fiber bundle, while the release agent ensures the separability of the monofilaments. All of these factors are beneficial for the heat treatment of the fiber, thereby improving the fiber strength.

[0095] The data comparison between Comparative Example 6 and Example 1 shows that if the proportion of dispersant in components A and B increases, the amount of dispersant coating on the fiber surface increases, which may occupy or cover some of the bundling agent and release agent sites, affecting the bundling and release effects, thereby reducing the fiber bundling properties, worsening the anti-adhesion situation, and consequently affecting the fiber heat treatment effect and the final fiber mechanical properties.

[0096] A comparison of the data from Comparative Example 7 and Example 1 shows that extending the grinding time during the preparation of the treatment agent leads to a decrease in fiber bundling and anti-adhesion effects, as well as a hardening of the fiber feel and a reduction in strength. Extended grinding time further reduces the particle size of the bundling agent and release agent, and disrupts the sheet-like structure of the bundling agent, affecting the fiber coating and bundling effect. Furthermore, smaller-sized release agents tend to embed themselves in the gaps of the bundling agent, failing to effectively prevent adhesion of the fiber filaments, thus affecting the fiber heat treatment effect.

[0097] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are exhaustively listed. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0098] For those skilled in the art, various modifications and improvements can be made without departing from the concept of the present invention, and these modifications and improvements are all within the scope of protection of the present invention. The scope of protection of the present invention is defined by the appended claims.

Claims

1. A liquid crystal polyarylate fiber treatment agent, characterized in that, The treatment agent comprises component A and component B. By weight, component A comprises 0.1-3 parts of a clustering agent, 0.1-3 parts of a dispersant, and 94.0-99.8 parts of deionized water. Component B, by weight, comprises 0.1-3 parts of release agent, 0.1-3 parts of dispersant, and 94.0-99.8 parts of deionized water.

2. The liquid crystal polyarylate fiber treatment agent according to claim 1, characterized in that, The slugging agent is at least one of hydrated aluminum silicate and polyethylene oxide.

3. The liquid crystal polyarylate fiber treatment agent according to claim 1, characterized in that, The separating agent is at least one of talc, colloidal silica, hexagonal boron nitride, and mica.

4. The liquid crystal polyarylate fiber treatment agent according to claim 1, characterized in that, The dispersant is sodium hexametaphosphate.

5. The liquid crystal polyarylate fiber treatment agent according to claim 1, characterized in that, The pH value of component A is 6.0-9.0, the solid content is 0.2-6%, and the viscosity at 25°C is 1-7 cp. The pH value of component B is 6.0-9.0, the solid content is 0.2-6%, and the viscosity at 25°C is 1-7 cp.

6. The liquid crystal polyarylate fiber treatment agent according to claim 1, characterized in that, The particle size D99 of the slugging agent is 1-10 μm, and when the slugging agent is polyethylene oxide, the weight-average molecular weight of polyethylene oxide is 500,000-1,000,000. The particle size D99 of the release agent is 2-10 μm.

7. The liquid crystal polyarylate fiber treatment agent according to claim 6, characterized in that, The particle size D99 of the clustering agent is smaller than that of the release agent.

8. A method for preparing a liquid crystal polyarylate fiber treatment agent according to any one of claims 1-7, characterized in that, The preparation method is as follows: Preparation of Component A: Add the bridging agent and dispersant to deionized water in proportion, stir and mix thoroughly, grind and filter to obtain Component A; Preparation of Component B: The separating agent and dispersant are added to deionized water in proportion, stirred and mixed thoroughly, then ground and filtered to obtain Component B.

9. The method for preparing a liquid crystal polyarylate fiber treatment agent according to claim 8, characterized in that, In the preparation of component A, the zirconium beads used in the grinding process were 0.2 mm in size, and the grinding time was 1-1.5 h. During the preparation of component B, the zirconium beads used in the grinding process were 0.4 mm in size, and the grinding time was 1-1.5 h.

10. An application of a liquid crystal polyarylate fiber treatment agent according to any one of claims 1-7, characterized in that, The treatment agent is applied to the melt spinning process of liquid crystal polyarylate, where component A is applied first, followed by component B, and the oiling rate of the liquid crystal polyarylate fiber is 0.5-1.4%.

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