Aromatic polyester fiber functional additive as well as preparation method and application thereof

Abstract

The invention relates to the field of aromatic polyester fiber spinning functional auxiliary agents, in particular to an aromatic polyester fiber functional auxiliary agent and a preparation method and application thereof. The lubricating and antistatic properties required by the aromatic polyester fiber in the spinning process can be met; the preparation method comprises the following steps: S1, mixing hydroxyl silicone oil and diisocyanate for reaction to obtain a polyurethane prepolymer; s2, sequentially adding phosphomonoester and carboxylic dihydric alcohol into the polyurethane prepolymer for chain extension; s3, adding phosphate diester into the mixture for end capping, adjusting the pH to be neutral, adding water, stirring and self-emulsifying to obtain the polyurethane-based fiber functional aid. The auxiliary agent can greatly improve the yarn forming type, the processability and the yield of the aromatic polyester fiber, can effectively prevent fusion among single fibers in the heat treatment process, and improves the yield.

Description

Technical Field

[0001] The invention relates to the field of aromatic polyester fiber spinning functional additives, in particular to an aromatic polyester fiber functional additive and a preparation method and application thereof. Background Art

[0002] In recent years, people have higher and higher requirements on the performance of synthetic fibers, especially high strength and high modulus (so-called super fibers). In order to meet these requirements, it is often necessary to carry out high temperature stretching or long-term high temperature heat treatment processing on the spun synthetic fibers.

[0003] By high-temperature stretching or long-term high-temperature heat treatment of synthetic fibers, the arrangement and orientation of the fiber molecular chains are improved to obtain high-strength and high-modulus synthetic fibers. The processing temperature of this process is often close to or slightly exceeds the melting point of the fiber. At this time, the fiber softens and single fiber contact and fusion occurs, resulting in fusion and adhesion between single fibers. Taking aromatic polyester fiber as an example, the fiber spun into silk needs to be placed in an oven and heat treated in a vacuum environment. The treatment conditions are 300℃ for more than 10h. At this temperature, single fibers will melt, contact and adhere to each other, and the heat treatment time is long, which conventional oils cannot withstand. Although silicone oils can withstand temperature and time, their poor antistatic properties lead to poor bundling during the spinning process, resulting in loose silk, spider web silk and other phenomena, which make subsequent heat treatment impossible. And if the fusion and adhesion between single fibers are serious, a large number of hairs and broken silks will be generated in the subsequent processing, and the fiber strength and modulus will be greatly reduced, so that it cannot meet market demand.

[0004] In order to solve this problem, many methods have been proposed, such as adding inorganic particles to traditional oils, such as using copper sulfate, mica powder, silica, etc. to treat the fiber surface, but this method cannot completely isolate single fibers, and some fibers still adhere. At the same time, a large number of inorganic particles impregnated on the fiber still exist after heat treatment, which has a bad effect on subsequent processing. In addition, the presence of inorganic particles causes the yarn to be fluffy, and the number of hairs and broken ends increases. Inspired by phosphorus-containing flame retardants, some researchers have tested organic phosphates as spinning aids, thereby avoiding the influence of inorganic particles on the subsequent application of yarns, but the permeability of phosphates is poor, resulting in the inability of the additives to be evenly distributed on the fiber surface. Therefore, during the long-term heat treatment of aromatic polyester fibers, the organic phosphates on the fiber surface are locally migrated due to the change in yarn stress, resulting in differences in the phosphate content on the fiber surface of the inner and outer layers of yarn, which in turn causes the inner layer of fibers to still adhere, resulting in a large amount of waste silk and reduced production efficiency. In addition, during the spinning process, organic phosphates will diffuse in the air in the form of tiny particles as the fibers shake, causing operators to inhale and poison. Therefore, simple organophosphates pose a threat to the health of operators. Summary of the invention

[0005] In order to solve the problems in the prior art, the purpose of the present invention is to provide an aromatic polyester fiber functional additive and its preparation method and application, to manufacture aromatic polyester fibers with a strength of 21 cN / dtex or above, and also includes a process of heat treating the fibers after applying the additive. The additive can not only meet the requirements of bundling and antistatic required for fiber production, but also effectively prevent single fiber fusion from occurring during the heat treatment process. At the same time, the additive always exists in the form of liquid or gel during the spinning process and will not form volatile small particles.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] The first aspect of the present invention provides a method for preparing an aromatic polyester fiber functional additive, comprising the following steps:

[0008] S1: hydroxy silicone oil, diisocyanate and initiator are mixed and reacted to obtain a polyurethane prepolymer;

[0009] S2: adding phosphate monoester and carboxylic acid diol to the polyurethane prepolymer in sequence to perform chain extension to obtain a chain-extended polyurethane;

[0010] S3: Add phosphate diester to the chain-extended polyurethane for end-capping, adjust the pH to neutral, add water and stir for self-emulsification to obtain a polyurethane-based fiber functional additive.

[0011] In a preferred embodiment, the step S1 is specifically as follows: firstly heating the hydroxy silicone oil to 70-80°C, then dropping diisocyanate until the isocyanate value in the reaction system is 25-40%, and then cooling to 50-55°C to obtain a polyurethane prepolymer.

[0012] The hydroxyl group and the isocyanate group react to form a carbamate bond. The purpose of using the hydroxyl silicone oil is to react with the diisocyanate and to retain the main part of the silicone oil after the carbamate bond is broken during the high-temperature heat treatment of the fiber after the additive is applied. In step S1, the heating process is to increase the reaction activity, and the cooling process is to prevent overreaction and excessive molecular weight of the polymer.

[0013] In a preferred embodiment, step S2 is specifically as follows: adding phosphoric acid monoester and carboxylic acid diol to the polyurethane prepolymer in sequence, heating to 60-65° C. after the addition is completed, and reacting at this temperature until the isocyanate value in the reaction system reaches 4-8%, thereby obtaining a chain-extended polyurethane.

[0014] The carboxylic acid diols include dimethylolbutyric acid and dimethylolpropionic acid, which act as anionic chain extenders to protonate the carboxylic acid groups in the subsequent neutralization stage, and the formed protonated chain segments function in the self-emulsification stage.

[0015] In steps S1 and S2, the isocyanate value is used to determine whether the corresponding polymerization reaction is completed.

[0016] In step S1, the diisocyanate is added at a speed of 1-2 drops / second. The reason for slow addition is to prevent implosion, that is, to prevent the formation of a polymer structure with a large molecular weight in an instant. The addition time of step S1 is generally controlled at 2-3 hours, and the amount of diisocyanate that can be added in one reaction is determined according to the addition speed and the addition time.

[0017] In step S2, the phosphoric acid monoester and the carboxylic acid diol are added at a rate of 3-5 drops / second, and the total addition time of the phosphoric acid monoester and the carboxylic acid diol is controlled within 2 hours.

[0018] In step S3, the phosphoric diester is added at a rate of 3-5 drops / second. The molar ratio of the phosphoric diester in step S3 to the hydroxy silicone oil in step S1 is 0.8-1.5:1; a slightly excessive amount of phosphoric diester is used for end-capping to ensure the end-capping efficiency and to increase the phosphoric acid ester content in the product.

[0019] In a preferred embodiment, step S3 specifically comprises: adding phosphate diester to the chain-extended polyurethane for end-capping, keeping the reaction warm until the isocyanate value in the reaction system is ≤0.5%, cooling, adjusting the pH to neutral, and then adding water for emulsification to obtain an aromatic polyester fiber functional additive.

[0020] Compared with conventional end-capping agents (such as butanone oxime and methyl ethyl ketone oxime), the end-capping with phosphate diesters can further increase the phosphate content in the functional additives and further avoid adhesion between single fibers.

[0021] In some embodiments, the hydroxy silicone oil includes at least one hydroxy silicone oil with a viscosity of 1000 to 10000 cs; when the viscosity of the hydroxy silicone oil is lower than 1000 cs, it evaporates faster during the heat treatment process, resulting in too little residual silicone oil in the later stage of the heat treatment and unable to play an effective barrier role; when the viscosity is higher than 10000 cs, the emulsion particle size is larger and the dispersion is uneven, resulting in a large number of adhesion points after heat treatment.

[0022] In some embodiments, the diisocyanate includes at least one of isophorone diisocyanate, toluene diisocyanate, o-phenylene diisocyanate, and hexamethylene diisocyanate.

[0023] In some embodiments, the carboxyl polyol compound includes at least one of dimethylolbutanoic acid and dimethylolpropionic acid;

[0024] In some embodiments, the phosphate monoester includes at least one of monobutyl phosphate, monohexyl phosphate, monooctyl phosphate, and monolauric phosphate;

[0025] In some embodiments, the phosphoric acid diester has a structural formula comprising at least one of dibutyl phosphate, dihexyl phosphate, dioctyl phosphate, and dilauric acid phosphate;

[0026] In some embodiments, the initiator includes at least one of dibutyltin dilaurate, dimethyltin diceneodecanoate, and dibutyltin maleate.

[0027] In some embodiments, the molar ratio of hydroxy silicone oil to diisocyanate in step S1 is 1:(2.2-2.6);

[0028] In step S2, the molar ratio of phosphoric acid monoester, carboxylic acid diol and diisocyanate is (0.2-0.3): (0.2-0.3): 1;

[0029] The water added in the self-emulsification process of adding water and stirring in step S3 is deionized water, and the amount of deionized water added is 5 to 10 times the mass of the reaction system added; the reaction system here refers to the reaction system of the end-capping reaction in step S3. Compared with the method of adding an external emulsifier, the self-emulsification method has a smaller emulsion particle size, a more uniform emulsion and is not easy to stratify. In addition, due to the smaller particle size and more uniform emulsification, the oil formed can reduce the number of adhesion points when used in the preparation of aromatic polyester fibers. At the same time, the external emulsifier is usually a polyether, which forms additional impurity contamination on the fiber surface during heat treatment.

[0030] The amount of the initiator added is 0.1% to 0.5% of the total mass of the hydroxy silicone oil and the diisocyanate;

[0031] In step S3, the blocking agent is added in an amount such that the isocyanate value (content) is ≤ 0.5% after being added to the reaction system.

[0032] More specifically, a method for preparing an aromatic polyester fiber functional additive comprises the following steps:

[0033] First, hydroxy silicone oil, diisocyanate, phosphoric acid monoester and carboxylic acid diol are vacuum dried at 100-110° C. for 4-6 hours;

[0034] S1: mixing hydroxy silicone oil and diisocyanate to react, to obtain a polyurethane prepolymer, the specific steps comprising: introducing nitrogen into the reactor for 2 hours to remove moisture in the reactor, first adding hydroxy silicone oil into the reactor, heating to 70-80°C under nitrogen protection, then slowly adding diisocyanate dropwise, taking a trace amount of the substance in the reaction system every 20 minutes during the reaction, titrating the isocyanate value in the reaction system by di-n-butylamine method until the isocyanate value in the system is 25-40%, then cooling to 50-55°C and keeping warm for 0.4-0.6h to obtain a polyurethane prepolymer;

[0035] Preferably, the viscosity of the hydroxy silicone oil is 2000-4000 cs;

[0036] S2: adding phosphate monoester and carboxylic acid diol to the polyurethane prepolymer in sequence to extend the chain, the specific steps include slowly dropping phosphate monoester and carboxylic acid diol monomers in the polyurethane prepolymer in the reaction kettle in sequence, heating to 60-65° C. after the dropwise addition is completed, and keeping the temperature to react until the isocyanate value in the reaction system is 4-8%, thereby obtaining the chain-extended polyurethane;

[0037] S3: After the chain extension, add phosphate diester to the polyurethane, and after the addition is completed, keep the temperature (the temperature is the same as S2) for 2-4 hours to react until the isocyanate content (i.e., isocyanate value) in the reaction system is ≤0.5%, and the polyurethane is capped. The reaction system is cooled to room temperature, and the pH of the reaction system is adjusted to neutral. Deionized water is slowly added and stirred at high speed to make it self-emulsified to obtain a polyurethane-based fiber functional additive;

[0038] Preferably, deionized water is added according to a solid content of 15%.

[0039] The second aspect of the present invention provides an aromatic polyester fiber functional additive prepared according to the above method, the structural formula of which includes: MBCBDBCBM;

[0040] The source of M is phosphoric acid diester, and the structural formula includes at least one of monobutyl phosphate, monohexyl phosphate, monooctyl phosphate and monolauric acid phosphate.

[0041] The structural formula of B includes Wherein, the source of R1 is diisocyanate, and the source of R2 is hydroxy silicone oil;

[0042] The source of C is a carboxylic acid diol, specifically including at least one of dimethylolbutanoic acid and dimethylolpropionic acid;

[0043] The source of D is a phosphoric acid monoester, including at least one of dibutyl phosphate, dihexyl phosphate, dioctyl phosphate and dilauric acid phosphate.

[0044] Wherein B is the structural unit formed by polymerization in step S1, and a polymer composed of several structural units B can be polymerized in step S1, and the degree of polymerization in step S1 is controlled by the slower dripping speed, the appropriate reaction temperature, whether to cool down, etc. The formation of the structural unit B is related to the mutual reaction mechanism and molar ratio of the active groups of diisocyanate and hydroxy silicone oil. Further polymerization is performed to obtain an auxiliary agent whose structure is mainly MBCBDBCBM, and the appropriate ratio of phosphate to silicone oil helps the two to better exert synergistic effects.

[0045] The diisocyanate polymerizes with the hydroxy silicone oil to form a B structure, which is equivalent to providing a polyurethane framework for the additive, thereby increasing the glass transition temperature of the hydroxy silicone oil. Diisocyanate is also used to polymerize with chain extenders, phosphate monoesters, and phosphate diesters. Increasing the glass transition temperature can enhance the thermal stability of the polymer while reducing the expansion coefficient. After the functional additive is treated on the polyester fiber, if the glass transition temperature is low, the oil film formed after wrapping the fiber will become sticky, causing the oil film to break easily. By increasing the glass transition temperature, this phenomenon can be avoided, that is, its stickiness to the roller can be reduced.

[0046] In the structural formula MBCBDBCBM, the phosphate monoester is located in the middle, the phosphate diester is located at both ends, and the silicone oil is located between the phosphate monoester and the phosphate diester. This uniform cross-distribution structure helps the phosphate ester and silicone oil to be evenly distributed and synergistic during the heat treatment process. If the phosphate diester is not used for end-capping during the preparation of the additive, the phosphate content in the structural formula is low, and it is impossible to form enough coke blocks to serve as nodes to support the single fibers so that they do not touch each other.

[0047] C is used for chain extension and self-emulsification. If the chain extender is omitted during the preparation of the additive, chain extension and self-emulsification cannot be achieved, and the structural formula of the additive is mainly MBDBM. The relative content of silicone oil is reduced, and it is impossible to provide a sufficient lubricating layer between nodes to avoid fiber fusion between nodes, and the surface tension and permeability of the emulsion are affected; an external emulsifier is required, and the resulting emulsion particle size is large and uneven, and there are many adhesion points after heat treatment.

[0048] The hydroxyl group of phosphoric acid diester is connected to the isocyanate group of B to form a carbamate bond; the hydroxyl group of carboxylic acid diol is connected to the isocyanate group of B to form a carbamate bond. The hydroxyl group of phosphoric acid monoester is connected to the isocyanate group of B to form a carbamate bond.

[0049] The third aspect of the present invention discloses an application of an aromatic polyester fiber functional additive, wherein the functional additive is used to inhibit the fusion of single fibers of the aromatic polyester fiber during heat treatment.

[0050] Preferably, before the aromatic polyester fiber is heat-treated, the first auxiliary agent system is added with an auxiliary agent, and the oil addition rate is 0.4-1.2% (wherein the oil refers to the aromatic polyester fiber functional auxiliary agent of the present invention). Specifically used for manufacturing aromatic polyester fibers with a strength of 21 cN / dtex and above, it also includes the step of heat-treating the fibers after the auxiliary agent is applied, and the heat treatment temperature should be ≥300°C.

[0051] Beneficial effects of the present invention:

[0052] 1. The additive of the present invention can help aromatic polyester fibers improve their bundling and antistatic properties during spinning, and can also prevent the fusion of single fibers during heat treatment, and provide excellent yarn manufacturing performance. It can improve production efficiency and will not produce scum to affect the fibers.

[0053] 2. The additive of the present invention combines phosphate ester with hydroxy silicone oil by polymerization. The polymer gives phosphate ester a certain fluidity, so that the additive will not quickly condense into a solid after being treated on the fiber surface but will exist in a gel state. Therefore, the phosphate ester will not diffuse into the air due to the shaking of the fiber during spinning. This not only reduces the quantitative error caused by the loss of the additive component, but also protects the health of the operator.

[0054] If the phosphate ester is directly mixed with the hydroxy silicone oil (instead of polymerized), the disadvantages include: before heat treatment, more water on the fiber surface evaporates, the phosphate ester component and the silicone oil component separate into phases, resulting in the migration of the phosphate ester during heat treatment and local aggregation. There is a difference in the phosphate ester content on the surface of the inner and outer yarn fibers, resulting in adhesion of the inner fibers. The locally aggregated phosphate ester also diffuses into the air due to the shaking of spinning.

[0055] 3. The working principle of the auxiliary agent of the present invention is different from that of traditional fiber oil agents. In traditional oil agents, such as polyester, nylon, and aramid oil agents, the fiber yield is mainly guaranteed by providing good lubricity to the fiber. The oil agent does not undergo chemical changes during the entire fiber production process. The application of the auxiliary agent of the present invention to the surface of aromatic polyester fiber is divided into two stages: the first stage, i.e., the spinning process, is no different from the traditional oil agent, but in the second stage, i.e., the heat treatment process, the auxiliary agent of the present invention will undergo a process of water volatilization-polymer decomposition, and the organic silicone oil component and the phosphate ester component in the polyurethane segment will be separated from the main chain due to the decomposition of chemical bonds. Subsequently, the phosphate ester continues to decompose into phosphoric acid and then decomposes into metaphosphoric acid to finally form polymetaphosphoric acid, which adheres to the fiber surface in the form of a coke block to avoid single fiber adhesion; the organic silicone oil does not react during the heat treatment process and keeps volatilizing slowly. During the heat treatment process, the phosphate ester forms a coke block to provide node support so that the single fibers will not contact each other, and the silicone oil provides a lubricating layer between the nodes to avoid fiber fusion between the nodes. The synergistic effect of the two makes it almost impossible to fuse the fibers after heat treatment. Improve fiber yield and reduce the amount of waste fiber.

[0056] 4. The present invention polymerizes phosphate ester and hydroxy silicone oil together, which not only retains the excellent permeability of silicone oil, but also does not affect the process of phosphate ester forming coke blocks. It allows the functional additive to better penetrate and wrap onto the surface of the single fiber, reducing the oil migration phenomenon during the heat treatment process.

[0057] The high content of hydroxy silicone oil makes the surface tension of the emulsion lower and increases the permeability. The other components besides phosphate ester and hydroxy silicone oil promote the formation of coke blocks during the coking process of phosphate ester. During the heating process, the phosphate ester first breaks the ester bond and degrades into phosphoric acid or phosphorus pentoxide, and then further degrades into metaphosphoric acid and then polymetaphosphoric acid. In the latter two steps, the surrounding alkyl structures will combine with it, thereby promoting the formation of coke and playing a barrier role.

[0058] If the phosphate ester is directly mixed with the hydroxy silicone oil, it will not only cause air pollution during spinning, but also cause obvious adhesion of the fibers after heat treatment, and there will be obvious particles and loose fibers under the SEM scanning electron microscope.

[0059] 4. An anionic chain extender is introduced into the preparation process of the auxiliary agent of the present invention, and the emulsion auxiliary agent is obtained by self-emulsification. The obtained emulsion particle size is smaller and the distribution on the fiber surface is more uniform. At the same time, the pollution and supply chain risks caused by the addition of emulsifiers can be avoided.

[0060] 5. The present invention adopts a one-step oiling method, which avoids the water washing and redundant oiling system required for two-step oiling, reduces equipment requirements and operating procedures, and improves production efficiency.

[0061] 6. The components of the present invention have poor heat resistance, and the amount of oil residue on the yarn surface after the heat treatment is extremely small, so there is no need to clean the yarn, thus avoiding the cleaning process.

[0062] 7. The preparation process of the aromatic polyester fiber functional additive of the present invention is simple, the equipment requirements are low, and the yield rate of produced fibers is high, which is conducive to the further industrial application of aromatic polyester fibers in composite materials and other fields. DETAILED DESCRIPTION

[0063] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0064] Unless otherwise specified, the test materials or reagents used in the following examples are all existing and can be obtained from commercial channels. If no specific techniques or conditions are specified in the examples, they can be carried out according to conventional techniques or conditions disclosed in the art.

[0065] The octyl group in the monooctyl phosphate and dioctyl phosphate used in the following examples and comparative examples is n-octyl; the monohexyl phosphate and dihexyl phosphate used in the following examples and comparative examples are n-hexyl; monolauric acid phosphate is monolauryl phosphate. The dimethylol propionic acid herein is 2,2-dimethylol propionic acid.

[0066] Example 1

[0067] First, 1000cs hydroxy silicone oil, isophorone diisocyanate, monooctyl phosphate and dimethylolbutyric acid were vacuum dried at 110°C for 6 hours;

[0068] S1: 1000cs hydroxy silicone oil and isophorone diisocyanate are mixed and reacted to obtain a polyurethane prepolymer, and the specific steps include: first introducing nitrogen into the reactor for 2 hours to remove the moisture in the reactor, first adding hydroxy silicone oil and dibutyltin dilaurate into the reactor, heating to 70°C under nitrogen protection, and then slowly dropping isophorone diisocyanate (dropping speed is 1 drop / second), taking a trace amount of substances in the reaction system every 20 minutes during the reaction process, using the di-n-butylamine method to titrate the isocyanate value in the reaction system until the isocyanate value in the system is 32%, and then cooling to 55°C and keeping warm for 0.5h to obtain a polyurethane prepolymer;

[0069] S2: adding monooctyl phosphate and dimethylolbutyric acid to the polyurethane prepolymer in sequence for chain extension, specifically comprising the steps of slowly dropping monooctyl phosphate and dimethylolbutyric acid monomers in sequence into the polyurethane prepolymer in the reaction kettle (dropping speed 3 drops / second), heating to 60° C. after the dropwise addition is completed, and keeping the temperature to react until the isocyanate value in the system reaches 6%, thereby obtaining the chain-extended polyurethane;

[0070] S3: Add dioctyl phosphate to the chain-extended polyurethane (the dropping speed is 3 drops / second). After the dropping is completed, keep the reaction at 60°C for 3 hours until the isocyanate content in the system is ≤0.5%, cap the polyurethane, cool the reaction system to room temperature, adjust the pH of the system to neutral, add ionized water (add deionized water according to the solid content of 15%) and stir at 1000r / min for 1 hour to make it self-emulsified, and obtain a polyurethane-based fiber functional additive;

[0071] The molar ratio of hydroxy silicone oil to isophorone diisocyanate is 1:2.4; the molar ratio of monooctyl phosphate, dimethylol butyric acid and isophorone diisocyanate is 0.25:0.25:1. The added mass of dibutyltin dilaurate is 0.3% of the mass of hydroxy silicone oil and isophorone diisocyanate. The amount of hydroxy silicone oil is 0.5 mol. The amount of dioctyl phosphate is 0.5 mol.

[0072] Aromatic polyester chips (type II polyarylate chips) were added to a single screw extruder for spinning, melted at 320°C, extruded from a 24-hole spinneret, and the filaments coming down from the spinning tunnel before stretching were added with a polyurethane-based fiber functional additive on the first oil system, with an oiling rate of 0.4%. After one stretching, the fibers were wound up at a winding speed of 1000 m / min to obtain nascent fibers. It was observed that the oil film formed by the functional additive was not sticky and did not stick to the roller (the same applies to the following examples).

[0073] The as-spun fibers were placed in a vacuum oven and treated at 300°C for 10 hours to obtain aromatic polyester fibers.

[0074] The relevant parameters of the processing additives for aromatic polyester fibers are shown in Table 1.

[0075] Example 2

[0076] First, 2000cs hydroxy silicone oil, o-phenylenediisocyanate, monohexyl phosphate and dimethylol propionic acid were vacuum dried at 110°C for 4 hours;

[0077] S1: 2000cs hydroxy silicone oil and o-phenylenedimethyl diisocyanate are mixed and reacted to obtain a polyurethane prepolymer, and the specific steps include: nitrogen is first introduced into the reactor for 2 hours to remove the moisture in the reactor, and the hydroxy silicone oil and dibutyltin dilaurate are first added into the reactor, and the temperature is raised to 80°C under nitrogen protection, and then o-phenylenedimethyl diisocyanate is slowly added dropwise (the dropping speed is 2 drops / second), and during the reaction process, a trace amount of the substance in the reaction system is taken every 20 minutes, and the isocyanate value in the reaction system is titrated by the di-n-butylamine method until the isocyanate value in the system is 40%, and then the temperature is lowered to 50°C and kept warm for 0.5h to obtain a polyurethane prepolymer;

[0078] S2: adding monohexyl phosphate and dimethylol propionic acid to the polyurethane prepolymer in sequence for chain extension, specifically comprising the steps of slowly dropping monohexyl phosphate and dimethylol propionic acid monomers in sequence to the polyurethane prepolymer in the reaction kettle (dropping speed is 4 drops / second), heating to 65° C. after the dropwise addition is completed, and keeping the temperature to react until the isocyanate value in the system reaches 8%, thereby obtaining the chain-extended polyurethane;

[0079] S3: Add dihexyl phosphate to the chain-extended polyurethane (the dropping speed is 4 drops / second). After the dropping is completed, keep the reaction at 65°C for 3 hours until the isocyanate content in the system is ≤0.5%, cap the polyurethane, cool the reaction system to room temperature, adjust the pH of the system to neutral, add deionized water (add deionized water according to the solid content of 15%) and stir at 1000r / min for 1 hour to make it self-emulsified, and obtain a polyurethane-based fiber functional additive;

[0080] The molar ratio of hydroxy silicone oil to o-phenylenedimethyl diisocyanate is 1:2.2; the molar ratio of monohexyl phosphate, dihydroxymethyl propionic acid and o-phenylenedimethyl diisocyanate is 0.2:0.2:1. The added mass of dibutyltin dilaurate is 0.3% of the mass of hydroxy silicone oil and o-phenylenedimethyl diisocyanate. The amount of hydroxy silicone oil is 0.5 mol. The amount of dihexyl phosphate is 0.5 mol.

[0081] Aromatic polyester chips (type II polyarylate chips) are added to a single-screw extruder for spinning, melted at a high temperature of 320°C, and extruded from a 24-hole spinneret. Before stretching, the filament bundle coming down from the spinning tunnel has a polyurethane-based fiber functional additive added to the first oil system with an oiling rate of 0.6%. After one stretching, it is wound up at a winding speed of 1500m / min.

[0082] The bundled fibers were placed in a vacuum oven and treated at 300°C for 10 hours to obtain aromatic polyester fibers.

[0083] The relevant parameters of the processing additives for aromatic polyester fibers are shown in Table 1.

[0084] Example 3

[0085] First, 10000cs hydroxy silicone oil, o-phthalic diisocyanate, monolauric phosphate and dimethylol propionic acid were vacuum dried at 100°C for 6 hours;

[0086] S1: 10000cs hydroxy silicone oil and o-phenylenedimethyl diisocyanate are mixed and reacted to obtain a polyurethane prepolymer, and the specific steps include: first introducing nitrogen into the reactor for 2 hours to remove the moisture in the reactor, first adding hydroxy silicone oil and dibutyltin dilaurate into the reactor, heating to 75°C under nitrogen protection, and then slowly dropping o-phenylenedimethyl diisocyanate (dropping speed is 1 drop / second), taking a trace amount of substances in the reaction system every 20 minutes during the reaction process, using the di-n-butylamine method to titrate the isocyanate value in the reaction system until the isocyanate value in the system is 30%, and then cooling to 52°C and keeping warm for 0.5h to obtain a polyurethane prepolymer;

[0087] S2: adding monolauric phosphate and dimethylol propionic acid to the polyurethane prepolymer in sequence to extend the chain, the specific steps comprising slowly dropping monolauric phosphate and dimethylol propionic acid monomers in sequence to the polyurethane prepolymer in the reaction kettle (dropping speed is 3 drops / second), heating to 60° C. after the dropwise addition is completed, and keeping the temperature to react until the isocyanate value in the system reaches 6%, thereby obtaining the chain-extended polyurethane;

[0088] S3: Add dioctyl phosphate to the chain-extended polyurethane (the dropping speed is 3 drops / second). After the dropping is completed, keep the reaction at 60°C for 3 hours until the isocyanate content in the system is ≤0.5%, cap the polyurethane, cool the reaction system to room temperature, adjust the pH of the system to neutral, add deionized water (add deionized water according to the solid content of 15%) and stir at 1000r / min for 1 hour to make it self-emulsified, and obtain a polyurethane-based fiber functional additive;

[0089] The molar ratio of hydroxy silicone oil to o-phenylenedimethyl diisocyanate is 1:2.6; the molar ratio of monolauric phosphate, dimethylol propionic acid and o-phenylenedimethyl diisocyanate is 0.3:0.3:1. The mass of dibutyltin dilaurate added is 0.3% of the mass of hydroxy silicone oil and o-phenylenedimethyl diisocyanate. The amount of hydroxy silicone oil used is 0.5 mol. The amount of dioctyl phosphate used is 0.5 mol.

[0090] Aromatic polyester chips (type II polyarylate chips) are added to a single-screw extruder for spinning, melted at a high temperature of 320°C, extruded from a 24-hole spinneret, and the filaments coming down from the spinning tunnel before stretching. Polyurethane-based fiber functional additives are added to the first oil system, and the filaments are wound up after one stretching. The oiling rate is 0.4% and the winding speed is 1000m / min.

[0091] The bundled fibers were placed in a vacuum oven and treated at 300°C for 10 hours to obtain aromatic polyester fibers.

[0092] The relevant parameters of the processing additives for aromatic polyester fibers are shown in Table 1.

[0093] Example 4

[0094] First, 1000cs hydroxy silicone oil, hexamethylene diisocyanate, monooctyl phosphate and dimethylol propionic acid were vacuum dried at 110°C for 5 hours;

[0095] S1: 1000cs hydroxy silicone oil and hexamethylene diisocyanate are mixed and reacted to obtain a polyurethane prepolymer, and the specific steps include: nitrogen is first introduced into the reactor for 2 hours to remove the moisture in the reactor, and the hydroxy silicone oil and dibutyltin dilaurate are first added into the reactor, and the temperature is raised to 70°C under nitrogen protection, and then hexamethylene diisocyanate is slowly added dropwise (the dropping speed is 2 drops / second), and a trace amount of the substance in the reaction system is taken every 20 minutes during the reaction process, and the isocyanate value in the reaction system is titrated by the di-n-butylamine method until the isocyanate value in the system is 25%, and then the temperature is lowered to 55°C and kept warm for 0.5h to obtain a polyurethane prepolymer;

[0096] S2: adding monooctyl phosphate and dimethylol propionic acid to the polyurethane prepolymer in sequence for chain extension, specifically comprising the steps of slowly dropping monooctyl phosphate and dimethylol propionic acid monomers in sequence to the polyurethane prepolymer in the reaction kettle (dropping speed is 4 drops / second), heating to 65° C. after the dropwise addition is completed, and keeping the temperature to react until the isocyanate value in the system reaches 8%, thereby obtaining the chain-extended polyurethane;

[0097] S3: Add dioctyl phosphate to the chain-extended polyurethane (the dropping speed is 4 drops / second). After the dropping is completed, keep the reaction at 65°C for 3 hours until the isocyanate content in the system is ≤0.5%, cap the polyurethane, cool the reaction system to room temperature, adjust the pH of the system to neutral, add deionized water (add deionized water according to the solid content of 15%) and stir at 1000r / min for 1 hour to make it self-emulsified, and obtain a polyurethane-based fiber functional additive;

[0098] The molar ratio of hydroxy silicone oil to hexamethylene diisocyanate is 1:2.3; the molar ratio of monooctyl phosphate, dimethylol propionic acid and hexamethylene diisocyanate is 0.25:0.25:1. The added mass of dibutyltin dilaurate is 0.3% of the mass of hydroxy silicone oil and hexamethylene diisocyanate. The amount of hydroxy silicone oil is 0.5 mol. The amount of dioctyl phosphate is 0.5 mol.

[0099] Aromatic polyester chips (type II polyarylate chips) are added to a single-screw extruder for spinning, melted at a high temperature of 320°C, and extruded from a 24-hole spinneret. Before stretching, the filament bundle coming down from the spinning tunnel has a polyurethane-based fiber functional additive added to the first oil system with an oiling rate of 1.0%. After one stretching, it is wound up at a winding speed of 1000m / min.

[0100] The bundled fibers were placed in a vacuum oven and treated at 300°C for 10 hours to obtain aromatic polyester fibers.

[0101] The relevant parameters of the processing additives for aromatic polyester fibers are shown in Table 1.

[0102] Example 5

[0103] First, 4000cs hydroxy silicone oil, hexamethylene diisocyanate, monooctyl phosphate and dimethylol propionic acid were vacuum dried at 100°C for 6 hours;

[0104] S1: 4000cs hydroxy silicone oil and hexamethylene diisocyanate are mixed and reacted to obtain a polyurethane prepolymer, and the specific steps include: first introducing nitrogen into the reactor for 2 hours to remove the moisture in the reactor, first adding hydroxy silicone oil and dibutyltin dilaurate into the reactor, heating to 75°C under nitrogen protection, and then slowly dropping hexamethylene diisocyanate (dropping speed is 1 drop / second), taking a trace amount of substances in the reaction system every 20 minutes during the reaction process, using the di-n-butylamine method to titrate the isocyanate value in the reaction system until the isocyanate value in the system is 30%, and then cooling to 50°C and keeping warm for 0.5h to obtain a polyurethane prepolymer;

[0105] S2: adding monooctyl phosphate and dimethylol propionic acid to the polyurethane prepolymer in sequence for chain extension, specifically comprising the steps of slowly dropping monooctyl phosphate and dimethylol propionic acid monomers in sequence to the polyurethane prepolymer in the reaction kettle (dropping speed is 4 drops / second), heating to 60° C. after the dropwise addition is completed, and keeping the temperature to react until the isocyanate value in the system reaches 5%, thereby obtaining the chain-extended polyurethane;

[0106] S3: Add dioctyl phosphate to the chain-extended polyurethane (the dropping speed is 4 drops / second). After the dropping is completed, keep the reaction at 60°C for 3 hours until the isocyanate content in the system is ≤0.5%, cap the polyurethane, cool the reaction system to room temperature, adjust the pH of the system to neutral, add deionized water (add deionized water according to the solid content of 15%) and stir at 1000r / min for 1 hour to make it self-emulsified, and obtain a polyurethane-based fiber functional additive;

[0107] The molar ratio of hydroxy silicone oil to hexamethylene diisocyanate is 1:2.5; the molar ratio of monooctyl phosphate, dimethylol propionic acid and hexamethylene diisocyanate is 0.3:0.3:1. The added mass of dibutyltin dilaurate is 0.3% of the mass of hydroxy silicone oil and hexamethylene diisocyanate. The amount of hydroxy silicone oil is 0.5 mol. The amount of dioctyl phosphate is 0.5 mol.

[0108] Aromatic polyester chips (type II polyarylate chips) are added to a single-screw extruder for spinning, melted at a high temperature of 320°C, and extruded from a 24-hole spinneret. Before stretching, the filament bundle coming down from the spinning tunnel has a polyurethane-based fiber functional additive added to the first oil system with an oiling rate of 1.2%. After one stretching, it is wound up at a winding speed of 1000m / min.

[0109] The bundled fibers were placed in a vacuum oven and treated at 300°C for 10 hours to obtain aromatic polyester fibers.

[0110] The relevant parameters of the processing additives for aromatic polyester fibers are shown in Table 1.

[0111] Example 6

[0112] First, 8000cs hydroxy silicone oil, hexamethylene diisocyanate, monooctyl phosphate and dimethylol propionic acid were vacuum dried at 110°C for 4 hours;

[0113] S1: 4000cs hydroxy silicone oil and hexamethylene diisocyanate are mixed and reacted to obtain a polyurethane prepolymer, and the specific steps include: first introducing nitrogen into the reactor for 2 hours to remove the moisture in the reactor, first adding hydroxy silicone oil and dibutyltin dilaurate into the reactor, heating to 75°C under nitrogen protection, and then slowly dropping hexamethylene diisocyanate (dropping speed is 1 drop / second), taking a trace amount of substances in the reaction system every 20 minutes during the reaction process, using the di-n-butylamine method to titrate the isocyanate value in the reaction system until the isocyanate value in the system is 30%, and then cooling to 55°C and keeping warm for 0.5h to obtain a polyurethane prepolymer;

[0114] S2: adding monooctyl phosphate and dimethylol propionic acid to the polyurethane prepolymer in sequence for chain extension, specifically comprising the steps of slowly dropping monooctyl phosphate and dimethylol propionic acid monomers in sequence to the polyurethane prepolymer in the reaction kettle (dropping speed is 3 drops / second), heating to 60° C. after the dropwise addition is completed, and keeping the temperature to react until the isocyanate value in the system reaches 6%, thereby obtaining the chain-extended polyurethane;

[0115] S3: Add dioctyl phosphate to the chain-extended polyurethane (the dropping speed is 3 drops / second). After the dropping is completed, keep the reaction at 60°C for 3 hours until the isocyanate content in the system is ≤0.5%, cap the polyurethane, cool the reaction system to room temperature, adjust the pH of the system to neutral, add deionized water (add deionized water according to the solid content of 15%) and stir at 1000r / min for 1 hour to make it self-emulsified, and obtain a polyurethane-based fiber functional additive;

[0116] The molar ratio of hydroxy silicone oil to hexamethylene diisocyanate is 1:2.5; the molar ratio of monooctyl phosphate, dimethylol propionic acid and hexamethylene diisocyanate is 0.3:0.3:1. The added mass of dibutyltin dilaurate is 0.3% of the mass of hydroxy silicone oil and hexamethylene diisocyanate. The amount of hydroxy silicone oil is 0.5 mol. The amount of dioctyl phosphate is 0.5 mol.

[0117] Aromatic polyester chips (type II polyarylate chips) are added to a single-screw extruder for spinning, melted at a high temperature of 320°C, and extruded from a 24-hole spinneret. Before stretching, the filament bundle coming down from the spinning tunnel has a polyurethane-based fiber functional additive added to the first oil system with an oiling rate of 1.2%. After one stretching, it is wound up at a winding speed of 1000m / min.

[0118] The bundled fibers were placed in a vacuum oven and treated at 300°C for 10 hours to obtain aromatic polyester fibers.

[0119] The relevant parameters of the processing additives for aromatic polyester fibers are shown in Table 1.

[0120] In all embodiments of the present invention, the dropping rate, polymerization temperature, and whether to cool down in step S1 have a great influence on the polymerization reaction. When the dropping rate is too high, or the polymerization temperature reaches above 85°C, or the polymerization temperature (70-80°C) is not cooled and kept at the polymerization temperature for 0.5h, it is found that the polymer becomes gel and a climbing phenomenon (i.e., implosion) occurs. In the end, it is impossible to obtain an emulsion with small and uniform particle size, and it is also impossible to reduce the number of adhesion points.

[0121] Comparative Example 1

[0122] It is basically the same as Example 1, except that 20000 cs hydroxy silicone oil is used.

[0123] Comparative Example 2

[0124] The method is substantially the same as Example 1, except that the phosphate monoester is monostearyl phosphate.

[0125] Comparative Example 3

[0126] The process is basically the same as Example 1, except that diethyltoluenediamine is used instead of dimethylolbutyric acid.

[0127] Comparative Example 4

[0128] The method is substantially the same as Example 1, except that the phosphate diester is replaced by distearyl phosphate.

[0129] Comparative Example 5

[0130] It is basically the same as Example 1, except that the oiling rate is 2.6%.

[0131] Comparative Example 6

[0132] It is basically the same as Example 1, except that the oiling rate is 3.5%.

[0133] Comparative Example 7

[0134] Mix 1000cs hydroxy silicone oil, monooctyl phosphate, and dioctyl phosphate; specifically, add 1000cs hydroxy silicone oil, monooctyl phosphate, and dioctyl phosphate, mix thoroughly, then add water (add deionized water according to 15% solid content), stir thoroughly at a speed of 1000r / min for 1h to form an emulsion. The addition amount of 1000cs hydroxy silicone oil, monooctyl phosphate, and dioctyl phosphate is the same as that in Example 1.

[0135] Aromatic polyester chips (type II polyarylate chips) are added to a single-screw extruder for spinning, melted at a high temperature of 320°C, and extruded from a 24-hole spinneret. The filaments coming down from the spinning tunnel before stretching are added with the above emulsion on the first oil system, with an oiling rate of 0.4%. After one stretching, they are wound up at a winding speed of 1000m / min.

[0136] The bundled fibers were placed in a vacuum oven and treated at 300°C for 10 hours to obtain aromatic polyester fibers.

[0137] The relevant parameters of aromatic polyester fibers for the treatment of additives are shown in Table 1.

[0138] Compared with Example 1, the hydroxy silicone oil, monooctyl phosphate, and dioctyl phosphate are directly mixed instead of being polymerized.

[0139] Comparative Example 8

[0140] It is basically the same as Example 1, except that the oiling rate is 0.2%.

[0141] Comparative Example 9

[0142] It is basically the same as Example 1, except that the viscosity of the hydroxy silicone oil is 500 cs.

[0143] Comparative Example 10

[0144] The method is substantially the same as Example 1, except that the phosphoric acid diester is replaced by methyl ethyl ketone oxime.

[0145] Comparative Example 11

[0146] The method is basically the same as Example 1, except that the phosphoric acid monoester is replaced by 1,4-butanediol, and the phosphoric acid diester is replaced by methyl ethyl ketone oxime.

[0147] Comparative Example 12

[0148] It is basically the same as Example 1, except that the hydroxy silicone oil is replaced by polytetrahydrofuran with a molecular weight of 15000 (which is basically the same as the molecular weight of 1000cs silicone oil).

[0149] Comparative Example 13

[0150] The process is basically the same as Example 1, except that dimethylolbutyric acid is omitted in step S2, and alkylphenol polyoxyethylene ether AEO9 is added during emulsification.

[0151] First, 1000cs hydroxy silicone oil, isophorone diisocyanate, and monooctyl phosphate were vacuum dried at 110°C for 6 hours;

[0152] S1: 1000cs hydroxy silicone oil and isophorone diisocyanate are mixed and reacted to obtain a polyurethane prepolymer, and the specific steps include: first introducing nitrogen into the reactor for 2 hours to remove the moisture in the reactor, first adding hydroxy silicone oil and dibutyltin dilaurate into the reactor, heating to 70°C under nitrogen protection, and then slowly dropping isophorone diisocyanate (dropping speed is 1 drop / second), taking a trace amount of substances in the reaction system every 20 minutes during the reaction process, using the di-n-butylamine method to titrate the isocyanate value in the reaction system until the isocyanate value in the system is 32%, and then cooling to 55°C and keeping warm for 0.5h to obtain a polyurethane prepolymer;

[0153] S2: adding monooctyl phosphate to the polyurethane prepolymer, specifically comprising slowly dropping monooctyl phosphate into the polyurethane prepolymer in the reaction kettle (dropping speed 3 drops / second), heating to 60° C. after the dropping is completed, and keeping the temperature to react until the isocyanate value in the system reaches 6%, thereby obtaining polyurethane;

[0154] S3: Add dioctyl phosphate to the polyurethane (the dropping speed is 3 drops / second). After the dropping is completed, keep the reaction at 60°C for 3 hours until the isocyanate content in the system is ≤0.5%, cap the polyurethane, cool the reaction system to room temperature, adjust the pH of the system to neutral, add alkylphenol polyoxyethylene ether AEO9, add deionized water (add deionized water according to the solid content of 15%) and stir at 1000r / min for 1 hour to obtain a polyurethane-based fiber functional additive;

[0155] The molar ratio of hydroxy silicone oil to isophorone diisocyanate is 1:2.4; the molar ratio of monooctyl phosphate, alkylphenol polyoxyethylene ether AEO9, and isophorone diisocyanate is 0.25:0.25:1. The added mass of dibutyltin dilaurate is 0.3% of the mass of hydroxy silicone oil and isophorone diisocyanate. The amount of hydroxy silicone oil and dioctyl phosphate is 0.5 mol.

[0156] Aromatic polyester chips are added to a single-screw extruder for spinning, melted at high temperature, extruded from a spinneret, and the filament bundle coming down from the spinning tunnel before stretching. A polyurethane-based fiber functional additive is added to the first oil system with an oiling rate of 0.4%. After one stretching, the fiber bundle is wound up at a winding speed of 1000m / min to obtain primary fibers.

[0157] The as-spun fibers were placed in a vacuum oven and treated at 300°C for 10 hours to obtain aromatic polyester fibers.

[0158] Test example

[0159] The aromatic polyester fiber additives and heat-treated fibers prepared in Examples 1-6 and Comparative Examples 1-13 were tested according to the following test methods:

[0160] 1. Emulsion particle size test:

[0161] Take a small amount of the emulsion to be tested at room temperature, dilute it 100 times with deionized water, and transfer it to the test glass tank. Use ZEN3700 Nano ZSE potential and particle size analyzer to test the particle size potential of the emulsion respectively.

[0162] 2. Mechanical stability test method:

[0163] At room temperature, take 30 ml of the emulsion into a 50 ml centrifuge tube and centrifuge it at 3000 r / min for half an hour using a desktop high-speed centrifuge TG16-WS. Then take out the centrifuge tube and observe whether there is any precipitation at the bottom of the centrifuge tube.

[0164] 3. Dilution stability test method:

[0165] In a 100ml test tube with a scale, add 5ml of the emulsion with a dropper, and then add 8ml of deionized water with a dropper. After fully shaking, place it on a test tube rack and observe whether there is stratification, water separation, or precipitation after 24h and 48h.

[0166] 4. Strength test method:

[0167] Take 5 fiber samples, 20cm in length, select the fixtures required for the test and install them on the machine. Use Instron 5965 universal testing machine for testing. The upper fiber fixture should be installed under the sensor and connected to the sensor, and the lower fixture should be installed on the base. Put the other end of the fiber sample into the lower fixture with a little force, and apply pre-tension to the lower end of the sample to make the sample straight. The upper fixture moves upward until the sample strip breaks. Each section of fiber is measured five times to take the average value.

[0168] 5. Oil content test method:

[0169] Take 5 fiber samples and use the Newmai Nuclear Magnetic Fiber Oil Content Tester to test the oil content of each sample. Take the average value after 5 tests.

[0170] 6. Single fiber adhesion test:

[0171] The adhesion points between single fibers within 1000 m were counted in a section of 1000 m. Five sections were taken from each bundle of fibers to count the adhesion points and the average value was calculated.

[0172] Table 1 Relevant test parameters of aromatic polyester fiber additives prepared in Examples 1-6 and Comparative Examples 1-13 and the fibers after heat treatment

[0173]

[0174]

[0175] Note: In the emulsion particle size, Z-Ave is the average particle size, Pk1 is the particle size of the first peak, Pk2 is the particle size of the second peak, and - means there is no second peak;

[0176] 1. The fiber strengths in Examples 1-6 are all greater than 21 cN / dtex, and the number of adhesion points between fibers is relatively small.

[0177] 2. Comparing Example 1 and Comparative Examples 1-6 in Table 1, the particle size of the emulsion designed by the present invention is smaller, which is more conducive to evenly distributing the additive on the fiber. Although some comparative examples have individual peaks with smaller particle sizes, there are double peaks, i.e., large particle size and small particle size, which makes the emulsion easy to stratify when testing stability, and the additive cannot be evenly distributed on the fiber.

[0178] 3. Comparing Example 1 and Comparative Example 3 in Table 1, the cationic system (ie, diethyltoluenediamine) in Comparative Example 3 has poor compatibility with the polyester fiber, resulting in uneven distribution of the oil film of the additive on the fiber surface.

[0179] 4. Comparing Example 1 and Comparative Example 1 in Table 1, the emulsion obtained by the silicone oil viscosity designed by the present invention is more stable. In Comparative Examples 2 and 4, the emulsion is uneven and easily stratified after self-emulsification, resulting in an increase in loose and hairy fibers during the spinning process, a decrease in fiber strength, and an increase in the number of adhesion points. In Comparative Examples 2 and 4, due to the change in the chemical composition of the phosphate ester, the carbon chain of the phosphate ester is too long, resulting in strong oiliness, insufficient polymer emulsification ability, demulsification or large emulsion particle size, and poor stability.

[0180] 5. Comparing Example 1 and Comparative Examples 5-6 in Table 1, the oil application rate is too high, resulting in too much residual additive. As the additive is continuously sintered into carbon during heat treatment, it adheres to the fiber surface, causing the oil film between fibers to be destroyed, resulting in contact and fusion between single fibers and an increase in adhesion points.

[0181] 6. Comparing Example 1 and Comparative Example 7 in Table 1, the oil obtained by directly mixing silicone oil and phosphate ester and then emulsifying with an external emulsifier has poor permeability because the phosphate ester exists in the tow in solid form, and the silicone oil has poor compatibility with it, resulting in the inability of the phosphate ester to be evenly dispersed inside the fiber, which results in poor fiber anti-adhesion effect.

[0182] 7. Comparing Example 1 and Comparative Example 8 in Table 1, the oiling rate is too low, resulting in poor yarn bundling during spinning, more loose yarns, and difficulty in maintaining long-term spinning. Therefore, the fiber strength and the number of adhesion points of Comparative Example 8 were not measured.

[0183] 8. Comparing Example 1 and Comparative Example 9 in Table 1, after the low-viscosity silicone oil is selected, it evaporates quickly during the heat treatment process, resulting in too little silicone oil residue in the later stage of the heat treatment (5-10h) to play an effective barrier role.

[0184] 9. Comparing Example 1 and Comparative Example 10 in Table 1, after the phosphate diester in the polymer structure is replaced, the fibers cannot form effective coke support with each other during the heat treatment process, resulting in aggravated fiber adhesion.

[0185] 10. Comparing Example 1 and Comparative Example 11 in Table 1, after the phosphate ester in the polymer structure is replaced, the fibers cannot form effective coke support with each other during the heat treatment process, resulting in serious fiber adhesion.

[0186] 11. Comparing Example 1 and Comparative Example 12 in Table 1, after replacing the silicone oil component, although a stable emulsion can be formed, a stable oil film cannot be formed on the fiber surface, and a barrier cannot be formed between fibers during the subsequent heat treatment process. Due to severe fiber adhesion, the fiber strength test cannot be performed.

[0187] 12. Comparing Example 1 and Comparative Example 13 in Table 1, after removing the carboxylic acid diol, the polymer loses its self-emulsification ability. After the emulsion is formed by adding alkylphenol polyoxyethylene ether, the emulsion particle size is large and the emulsification is uneven, resulting in uneven distribution of the additive after being treated on the fiber surface, which in turn leads to poor fiber anti-adhesion effect; and if the added emulsifier alkylphenol polyoxyethylene ether is replaced by dihydroxymethylbutyric acid (added), the emulsion cannot be formed and the subsequent steps (oiling and performance measurement) cannot be carried out.

[0188] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A method for preparing an aromatic polyester fiber functional additive, characterized in that: The steps include: S1: hydroxy silicone oil, diisocyanate and initiator are mixed and reacted to obtain a polyurethane prepolymer; S2: adding phosphate monoester and carboxylic acid diol to the polyurethane prepolymer in sequence to perform chain extension to obtain a chain-extended polyurethane; S3: Add phosphate diester to the chain-extended polyurethane for end-capping, adjust the pH to neutral, add water and stir for self-emulsification to obtain a polyurethane-based fiber functional additive.

2. The method for preparing an aromatic polyester fiber functional additive according to claim 1, characterized in that: The step S1 specifically comprises: firstly heating the hydroxy silicone oil to 70-80° C., then dropping diisocyanate until the isocyanate value in the reaction system is 25-40%, and then cooling to 50-55° C. to obtain a polyurethane prepolymer.

3. The method for preparing an aromatic polyester fiber functional additive according to claim 1, characterized in that: The step S2 specifically comprises: sequentially adding phosphoric acid monoester and carboxylic acid diol to the polyurethane prepolymer, heating to 60-65° C. after the addition is completed, and reacting at this temperature until the isocyanate value in the reaction system reaches 4-8%, thereby obtaining a chain-extended polyurethane.

4. The method for preparing an aromatic polyester fiber functional additive according to claim 1, characterized in that: The step S3 specifically comprises: adding phosphate diester to the chain-extended polyurethane for end-capping, keeping the temperature to react until the isocyanate value in the reaction system is ≤0.5%, cooling, adjusting the pH to neutral, and then adding water for emulsification to obtain an aromatic polyester fiber functional additive.

5. The method for preparing a functional additive for aromatic polyester fiber according to claim 1, characterized in that: The hydroxy silicone oil includes at least one of hydroxy silicone oils having a viscosity of 1000 to 10000 cs; The diisocyanate includes at least one of isophorone diisocyanate, toluene diisocyanate, o-phenylene diisocyanate and hexamethylene diisocyanate.

6. The method for preparing an aromatic polyester fiber functional additive according to claim 1, characterized in that: The phosphate monoester includes at least one of monobutyl phosphate, monohexyl phosphate, monooctyl phosphate, and monolauric phosphate; The carboxylic acid diol includes at least one of dimethylolbutanoic acid and dimethylolpropionic acid; The phosphoric acid diester includes at least one of dibutyl phosphate, dihexyl phosphate, dioctyl phosphate, and dilauric acid phosphate; The initiator includes at least one of dibutyltin dilaurate, dimethyltin diceneodecanoate, and dibutyltin maleate.

7. The method for preparing an aromatic polyester fiber functional additive according to claim 1, characterized in that: In step S1, the molar ratio of hydroxy silicone oil to diisocyanate is 1:(2.2-2.6); In step S2, the molar ratio of phosphoric acid monoester, carboxylic acid diol and diisocyanate is (0.2-0.3): (0.2-0.3): 1; The water added in the self-emulsification process of adding water and stirring in step S3 is deionized water, and the amount of deionized water added is 5 to 10 times the mass of the added reaction system; The amount of the initiator added is 0.1% to 0.5% of the total mass of the hydroxy silicone oil and the diisocyanate; In step S3, the blocking agent is added in an amount such that the isocyanate value is ≤0.5% after being added to the reaction system.

8. The aromatic polyester fiber functional additive prepared by the preparation method according to any one of claims 1 to 7, wherein the structural formula is MBCBDBCBM; The source of M is a phosphoric acid diester, and the structural formula includes at least one of dibutyl phosphate, dihexyl phosphate, dioctyl phosphate, and dilauric acid phosphate; The structural formula of B includes The source of R1 is diisocyanate, and R2 is hydroxy silicone oil; The source of C is a carboxylic acid diol, wherein the carboxylic acid diol is at least one of dimethylolbutyric acid and dimethylolpropionic acid; The source of D is a phosphoric acid monoester, including at least one of monobutyl phosphate, monohexyl phosphate, monooctyl phosphate and monolauric acid phosphate.

9. Use of the aromatic polyester fiber functional additive according to claim 8.

10. The use of the aromatic polyester fiber functional additive according to claim 9, characterized in that: Before the aromatic polyester fiber is heat-treated, the additive is added to the first additive system, the winding speed is 1000-1500 m / min, and the oiling rate is 0.4-1.2%.

11. The use of the aromatic polyester fiber functional additive according to claim 9, characterized in that: The method comprises manufacturing an aromatic polyester fiber having a strength of 21 cN / dtex or more, and also heat treating the fiber after applying an auxiliary agent.

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