Preparation method of polyphenylene sulfide chelate fiber

Abstract

The invention discloses a preparation method of polyphenylene sulfide based chelate fibers. The preparation method comprises the following steps: adding polyphenylene sulfide fibers into a reactor, adding a solvent for full swelling, then adding a cross-linking agent and a catalyst for reaction, and treating the obtained product to obtain cross-linked PPS fibers; adding the cross-linked PPS fiber into a solvent for swelling, then adding a nitration reagent for reaction, and treating a product after the reaction to obtain modified nitrocellulose PPS-NO2; the modified nitrocellulose PPS-NO2 is added into a solvent for swelling, then a reducing agent is added for a reduction reaction, a product obtained after the reaction is treated, and amino polyphenylene sulfide fiber PPS-NH2 is obtained; and adding the amino polyphenylene sulfide fiber PPS-NH2 into a solvent, and then adding a functional monomer to carry out grafting reaction, thereby obtaining the product polyphenylene sulfide-based chelate fiber. By utilizing the method to prepare the chelating functional fiber, the use defect of strong cancerogenic substances such as chloromethyl ether in the prior art can be effectively avoided. Meanwhile, the polyphenylene sulfide-based chelate fiber prepared by the method has relatively good stability and acid and alkali resistance.

Description

1. Technical field:

[0001] The invention relates to a method for preparing chelated fiber, in particular to a method for preparing polyphenylene sulfide-based chelated fiber. 2. Background technology:

[0002] Chelating fiber is a type of fiber material with adsorption and separation functions and a new type of adsorption and separation material developed in recent years. According to the conventional classification method, chelating fibers and ion exchange fibers are generally referred to as ion exchange fibers. Similar to ion exchange resin materials, the matrix used in fibrous adsorption materials is organic polymer, and the process of modifying the matrix and obtaining active functional groups with ion exchange and chelating properties is basically the same. Chelating fiber has the advantages of ion exchange fiber, and also has advantages that other ion exchange fibers do not have, such as high selectivity for ion adsorption and higher adsorption capacity. Compared with chelating resins, chelating fibers have the advantages of large effective specific surface area, fast exchange and elution speed, easy regeneration, diverse application forms, can be used in both liquid and gas phases, and low fluid resistance.

[0003] Chelated fiber can be considered to be composed of two parts, namely, base fiber and chelate group connected thereto. Base fibers include polypropylene, polyvinyl alcohol, acrylic fiber and polyphenylene sulfide, and chelate groups include amidoxime, amide, amine, thiourea and imidazole. Different base fibers are connected to different chelate groups by different methods to obtain chelate fibers with different properties. Due to its superior physical and chemical properties, chelate fiber has a wide range of application value in metal resource protection, water treatment and utilization of marine resources.

[0004] At present, there are two main methods for the preparation of chelated fibers: chemical grafting and irradiation grafting. Chemical grafting is widely used at present. However, the current chemical grafting method still faces some problems. For example, the crosslinking agent currently used in PPS-based fibers is a strong carcinogenic methylating agent-chloromethyl methyl ether, which causes serious environmental pollution. Therefore, it is of great significance to study new methods that can replace the strong carcinogen chloromethyl ether to prepare chelated fibers with equivalent functions. 3. Summary of the invention:

[0005] The technical problem to be solved by the present invention is: in order to overcome the technical difficulties of using toxic and harmful (chloromethyl methyl ether) raw materials and complicated reaction steps in the existing chelate fiber preparation, the present invention provides a novel preparation method of polyphenylene sulfide-based chelate fiber. The polyphenylene sulfide-based chelate fiber is prepared by the present invention, which solves the problem of serious environmental pollution caused by using a strong carcinogenic methylating agent-chloromethyl methyl ether as a cross-linking agent in the chemical grafting method, and utilizes the reducible characteristic of the nitro group to reduce the nitro group to an amino group, and grafts a functional monomer on the amino group, thereby obtaining a novel polyphenylene sulfide-based chelate fiber.

[0006] In order to solve the above problems, the technical solution adopted by the present invention is:

[0007] The present invention provides a method for preparing a polyphenylene sulfide-based chelate fiber, the preparation method comprising the following steps:

[0008] a. Add polyphenylene sulfide fiber into a reaction container, then add solvent to fully swell (swelling time is 6 to 12 hours), add crosslinking agent and catalyst after swelling, stir or ultrasonically disperse evenly, then heat to 70 to 80°C, and react under this temperature condition for 12 to 48 hours; after the reaction, cool to room temperature, filter, filter out the obtained product, wash the obtained product with alcohol, boil with acid, wash with water and dry it in turn to obtain crosslinked polyphenylene sulfide fiber, i.e., crosslinked PPS fiber;

[0009] b. Add the cross-linked PPS fiber obtained in step a to a solvent to fully swell, add a nitrating agent after swelling, stir or ultrasonically disperse it evenly, then heat it to 40-60° C., and react under this temperature condition for 1-6 hours; after the reaction is completed, cool it to room temperature, filter it, filter out the obtained product, wash the obtained product with alcohol, wash it with water and dry it in turn to obtain modified nitrocellulose PPS-NO2;

[0010] Place the modified nitrocellulose PPS-NO2 in a container, add a solvent to swell it; then add a reducing agent, heat it to 50-100°C and react for 1-6 hours; after the reaction, cool it to room temperature, filter it, and sequentially wash the product with alcohol, boil it with acid, wash it with water and dry it to obtain amino polyphenylene sulfide fiber PPS-NH2;

[0011] c. Place the obtained amino polyphenylene sulfide fiber PPS-NH2 in a container and add solvent A; then add functional monomers and heat to 60-120°C for reaction for 4-6 hours; after the reaction is completed, cool to room temperature, filter, and sequentially wash the product with alcohol, water and dry to obtain PPS-based chelated functional fiber, i.e., polyphenylene sulfide-based chelated fiber.

[0012] According to the above-mentioned preparation method of polyphenylene sulfide-based chelating fiber, the mass volume ratio between the added amount of polyphenylene sulfide fiber and the solvent in step a is 1g:50~100mL, the molar ratio between the added amount of polyphenylene sulfide fiber and the cross-linking agent is 1:0.5~8, and the molar ratio between the added amount of polyphenylene sulfide fiber and the catalyst is 1:1.2~2.2.

[0013] According to the above-mentioned preparation method of polyphenylene sulfide-based chelating fiber, the solvent in step a is 1,2-dichloroethane; the catalyst is anhydrous aluminum trichloride, anhydrous ferric trichloride or anhydrous tin tetrachloride; and the crosslinking agent is at least one of dimethoxymethane, ethylene glycol dimethyl ether and 1,4-dimethoxybenzene.

[0014] According to the above-mentioned preparation method of polyphenylene sulfide-based chelating fiber, the specific operation process of sequentially washing the obtained product with alcohol, boiling with acid, washing with water and drying in step a is: the obtained product is sequentially washed with anhydrous ethanol, boiled with a 1-2 mol / L HCl solution at 50°C for 5-6h, washed with water until neutral, and then vacuum dried at 50-60°C to constant weight.

[0015] According to the above-mentioned preparation method of polyphenylene sulfide-based chelating fiber, the solvent in step b is 1,2-dichloroethane; the nitrating agent is a mixed acid of concentrated sulfuric acid and concentrated nitric acid, and the molar ratio of concentrated nitric acid to concentrated sulfuric acid when mixed is 1:3-7 (concentrated sulfuric acid in the mixed acid is a functionalizing agent and nitric acid is an acidifying agent); the reducing agent is stannous chloride or reduced iron powder (wherein, when stannous chloride is used as the reducing agent, concentrated hydrochloric acid needs to be added as a catalyst; when reduced iron powder is used as the reducing agent, ammonium chloride needs to be added as a catalyst).

[0016] According to the above-mentioned preparation method of polyphenylene sulfide-based chelating fiber, the mass volume ratio between the cross-linked PPS fiber and the solvent added in step b is 1g:50-100mL, and the molar ratio between the cross-linked PPS fiber and the nitrating agent is 1:0.5-2;

[0017] The mass volume ratio between the modified nitrocellulose PPS-NO2 and the solvent is 1g:50-100mL, and the mass volume ratio between the modified nitrated PPS-NO2 fiber and the reducing agent is 1:1-5.

[0018] According to the above-mentioned preparation method of polyphenylene sulfide-based chelating fiber, the specific process of sequentially alcohol-washing, water-washing and drying the obtained product in step b is: the obtained product is sequentially washed with anhydrous ethanol, then washed with water until neutral, and then vacuum-dried to constant weight under the conditions of vacuum degree of 0.08Mpa and drying temperature of 50-60°C; the specific process of sequentially alcohol-washing, acid-boiling, water-washing and drying the product is: the obtained product is sequentially washed with anhydrous ethanol, boiled with 1-2mol / L HCl solution at 50°C for 5-6h, washed with water until neutral, and then vacuum-dried to constant weight under the conditions of vacuum degree of 0.08Mpa and drying temperature of 50-60°C.

[0019] According to the above-mentioned preparation method of polyphenylene sulfide-based chelating fiber, the mass volume ratio between the amino polyphenylene sulfide fiber PPS-NH2 and the solvent A added in step c is 1g:50~100mL, and the molar ratio between the amino polyphenylene sulfide fiber PPS-NH2 and the functional monomer added is 1:1~10.

[0020] According to the above-mentioned preparation method of polyphenylene sulfide-based chelating fiber, the solvent A in step c is 1,2-dichloroethane or hydrochloric acid; the functional monomer is at least one of sodium chloroacetate, phosphorous acid and 2-chlorobenzothiazole (when grafting phosphorous acid, hydrochloric acid is used as solvent, trioxymethylene reacts with amino group to generate methylamino intermediate, and then reacts with phosphorous acid to obtain the target product; 1,2-dichloroethane is used as solvent when grafting sodium chloroacetate and 2-chlorobenzothiazole).

[0021] According to the above-mentioned preparation method of polyphenylene sulfide-based chelating fiber, the specific process of sequentially washing the product with alcohol, washing with water and drying in step c is: the obtained product is sequentially washed with anhydrous ethanol and washed with water until neutral, and then vacuum dried to constant weight under the conditions of a vacuum degree of 0.08Mpa and a drying temperature of 50-60°C.

[0022] The positive beneficial effects of the present invention are:

[0023] 1. The technical solution of the present invention is to cross-link the fiber matrix for the first time through the Friedel-Crafts alkylation reaction of the cross-linking agent and the benzene ring, and then introduce nitro groups on the benzene ring by using a mixed acid nitrating reagent for nitration reaction, reduce the introduced nitro groups to amino groups, and graft functional monomers on the amino groups to obtain a new type of chelated functional fiber.

[0024] 2. The technical solution of the present invention adopts cheap and readily available industrial raw materials such as polyphenylene sulfide fiber, nitric acid and concentrated sulfuric acid, avoiding the use of strong carcinogenic reagents (chloromethyl methyl ether). Therefore, it has the advantages of being environmentally friendly and having obvious economic benefits, which is beneficial to environmental protection.

[0025] 3. The technical solution of the present invention simplifies the existing nitration reaction and better controls the reaction process. The present invention adopts a new preparation method with a simple reaction process, convenient operation, short time, low energy consumption, easy treatment and low pollution.

[0026] 4. The polyphenylene sulfide-based chelated functional fiber synthesized by the present invention has good 2+ Cr 6+ 、Ni 2+ The plasma has a very impressive adsorption performance, and after 5 adsorption-desorption cycles, it still has 95% of the initial adsorption capacity.

[0027] 5. The present invention obtains a series of fibers with chelating function by changing the reagents used, which provides a new idea for the preparation of chelating fibers.

[0028] In summary, the present invention has significant economic and social benefits. 4. Description of the drawings:

[0029] Figure 1: (a) Scanning electron micrographs of the original matrix fiber and (b) the polyphenylene sulfide-based sodium acetate chelating functional fiber prepared in Example 1.

[0030] Depend on Figure 1 It can be seen that the surface of the original matrix fiber is smooth, and the surface of the chelated functional fiber obtained after a series of reactions becomes rough, and attachments begin to appear on the fiber surface, proving that the reaction is successful.

[0031] Figure 2 : (c) Scanning electron micrographs of the original matrix fiber and (d) the polyphenylene sulfide-based thiazole chelating functional fiber prepared in Example 5.

[0032] Depend on Figure 2 It can be seen that the surface of the original matrix fiber is smooth, and the surface of the chelated functional fiber obtained after a series of reactions becomes rough, and attachments begin to appear on the fiber surface, proving that the reaction is successful.

[0033] Figure 3 FT-IR spectra of the raw material polyphenylene sulfide fiber PPS of the present invention and the polyphenylene sulfide-based phosphoric acid-type chelating functional fiber prepared in Example 3.

[0034] pass Figure 3 It can be seen from FT-IR that at 3000~3500cm -1 The stretching vibration absorption peak of OH appears at 1160cm -1 The bending vibration absorption peak of P=O appears at , indicating that chloromethylphosphoric acid is successfully grafted onto the fiber.

[0035] Figure 4 A schematic diagram of the reaction for preparing sodium polyphenylene sulfide acetate type chelating functional fiber according to Example 1 of the present invention.

[0036] Figure 5 A schematic diagram of the reaction for preparing polyphenylene sulfide-based phosphoric acid-type chelating functional fibers according to Example 3 of the present invention.

[0037] Figure 6 A schematic diagram of the reaction for preparing polyphenylene sulfide-based thiazole-type chelating functional fibers according to Example 5 of the present invention.

[0038] Figure 7 The polyphenylene sulfide-based sodium acetate chelating functional fiber prepared in Example 1 of the present invention is Ni 2+ Adsorption performance diagram of

[0039] Depend on Figure 7 It can be seen that the polyphenylene sulfide sodium acetate chelating functional fiber prepared in Example 1 still has good adsorption performance after desorption and regeneration for 5 times.

[0040] Figure 8 Example 3 of the present invention prepares the obtained polyphenylene sulfide-based phosphoric acid type chelating functional fiber for Cr6+ Adsorption performance diagram of

[0041] Depend on Figure 8 It can be seen that the polyphenylene sulfide-based phosphoric acid-type chelating functional fiber prepared in Example 3 still has good adsorption performance after being desorbed and regenerated 5 times.

[0042] Fig. 9 The polyphenylene sulfide-based thiazole chelating fiber prepared in Example 5 of the present invention is effective for Cu 2+ Adsorption performance diagram of

[0043] Depend on Fig. 9 It can be seen that the polyphenylene sulfide-based thiazole chelating fiber prepared in Example 5 still has good adsorption performance after being desorbed and regenerated 5 times. V. Specific implementation methods:

[0044] The present invention is further described below in conjunction with embodiments, but the protection scope of the technical solution of the present invention is not limited thereto.

[0045] Embodiment 1:

[0046] The preparation method of the polyphenylene sulfide sodium acetate type chelating functional fiber of the present invention comprises the following detailed steps:

[0047] a. First, weigh 0.43g (0.004mol) of polyphenylene sulfide fiber PPS and add it to the reaction bottle, then add 43mL of 1,2-dichloroethane and let it stand for swelling for 12h. After swelling, add 2.83mL (0.032mol) of dimethoxymethane and 1.17g (0.0088mol) of anhydrous aluminum chloride and stir evenly, then heat to 70℃ and react at this temperature for 24h. After the reaction, cool to room temperature, filter and filter out the product. The product is washed with anhydrous ethanol, boiled with 2mol / L HCl solution at 50℃ for 6h, washed with water until neutral, and vacuum dried to constant weight (vacuum degree is 0.08Mpa, drying temperature is 60℃, and drying time is 24h). After drying, cross-linked polyphenylene sulfide fiber is obtained (relative to the original polyphenylene sulfide fiber, the modified fiber has a weight increase of 2%).

[0048] b. Add the obtained cross-linked polyphenylene sulfide fiber to 43 mL of 1,2-dichloroethane and let it stand for swelling for 12 hours; after swelling, add 5 mL of mixed acid and stir evenly (the mixed acid is a mixture of concentrated sulfuric acid and concentrated nitric acid in a molar ratio of 3:1), then heat to 60°C and react at this temperature for 1 hour; after the reaction is completed, cool to room temperature, filter, filter out the obtained product, wash the obtained product with anhydrous ethanol and water in turn until neutral, and vacuum dry to constant weight (vacuum degree is 0.08 MPa, drying temperature is 60°C, and drying time is 24 hours), and obtain modified nitrated PPS-NO2 fiber after drying;

[0049] The modified nitrated PPS-NO2 fiber was placed in 30 mL of 1,2-dichloroethane and allowed to swell for 12 h, and then 1 g of stannous chloride as a reducing agent and 20 mL of concentrated hydrochloric acid as a catalyst were added, and the temperature was raised to 90 ° C for reduction reaction for 5 h; after the reaction, it was cooled to room temperature and filtered to obtain the product; the obtained product was washed with anhydrous ethanol, and then boiled with 1 mol / L hydrochloric acid at 50 ° C for 5 h, and then washed with water until neutral, and vacuum dried to constant weight (vacuum degree of 0.08 MPa, drying temperature of 60 ° C, drying time of 24 h), and amino polyphenylene sulfide fiber PPS-NH2 was obtained after drying (compared with before the reaction, the fiber weight increased by 16%);

[0050] c. The obtained amino polyphenylene sulfide fiber PPS-NH2 was placed in 50 mL of 1,2-dichloroethane and allowed to swell for 12 h, and then 4.6 g of sodium chloroacetate was added, and the temperature was raised to 100 ° C for reaction for 5 h; after the reaction was completed, it was cooled to room temperature and filtered to obtain the product, and the obtained product was washed with anhydrous ethanol and water to neutrality in turn, and finally vacuum dried to constant weight (vacuum degree of 0.08 MPa, drying temperature of 60 ° C, drying time of 24 h), and polyphenylene sulfide sodium acetate chelating functional fiber was obtained after drying (compared with before the reaction, the fiber weight increased by 35.8%).

[0051] The corresponding element analysis EA data analysis was performed on the fiber prepared in Example 1 of the present invention. The analysis results are shown in Table 1. The data in Table 1 show that sodium chloroacetate was successfully grafted onto the polyphenylene sulfide fiber.

[0052] Table 1 EA data of the fiber element analysis obtained in Example 1 of the present invention

[0053]

[0054] Embodiment 2:

[0055] The preparation method of the polyphenylene sulfide sodium acetate type chelating functional fiber of the present invention comprises the following detailed steps:

[0056] a. First, weigh 1.5g (0.014mol) of polyphenylene sulfide fiber PPS and add it to the reaction bottle, then add 150mL of 1,2-dichloroethane and let it stand for swelling for 12h. After swelling, add 8.5mL (0.11mol) of dimethoxymethane and 4.1g (0.03mol) of anhydrous aluminum chloride and stir evenly, then heat to 70℃ and react at this temperature for 24h. After the reaction is completed, cool to room temperature, filter and filter out the obtained product, wash the obtained product with anhydrous ethanol, boil it with 1mol / L HCl solution at 50℃ for 5h, wash it with water until it is neutral, and then vacuum dry it to constant weight (vacuum degree is 0.08Mpa, drying temperature is 60℃, and drying time is 24h); after drying, dimethoxymethane cross-linked polyphenylene sulfide fiber is obtained (relative to the original polyphenylene sulfide fiber, the modified fiber increases weight by 3%).

[0057] b. Add 150 mL of 1,2-dichloroethane to the obtained dimethoxymethane cross-linked polyphenylene sulfide fiber and let it stand for swelling for 12 hours; then add 15 mL of mixed acid and stir evenly (the mixed acid is a mixture of concentrated sulfuric acid and concentrated nitric acid in a molar ratio of 3:1), then heat to 60°C, and react at this temperature for 1 hour; after the reaction is completed, cool to room temperature, filter, filter out the obtained product, wash the obtained product with anhydrous ethanol and water in turn until neutral, and vacuum dry to constant weight (vacuum degree is 0.08Mpa, drying temperature is 60°C, and drying time is 24h), and obtain modified nitrated PPS-NO2 fiber after drying;

[0058] The obtained modified nitrated PPS-NO2 fiber was placed in 90 mL of 1,2-dichloroethane and allowed to swell for 12 h, and then 3.5 g of reduced iron powder and 1 g of ammonium chloride were added as a reducing agent, and the temperature was raised to 80 ° C for reduction reaction for 3 h; after the reaction, it was cooled to room temperature and filtered to obtain the product; the obtained product was washed with anhydrous ethanol, and then boiled with 1 mol / L hydrochloric acid at 50 ° C for 5 h, and then washed with water until neutral, and vacuum dried to constant weight (vacuum degree of 0.08 MPa, drying temperature of 60 ° C, drying time of 24 h), and amino polyphenylene sulfide fiber PPS-NH2 was obtained after drying (compared with before the reaction, the fiber weight increased by 14.6%);

[0059] c. The obtained amino polyphenylene sulfide fiber PPS-NH2 was placed in 50 mL of 1,2-dichloroethane and allowed to swell for 12 h, and then 10 g of sodium chloroacetate was added, and the temperature was raised to 100 ° C for reaction for 5 h; after the reaction was completed, it was cooled to room temperature, filtered to obtain the product, and washed with anhydrous ethanol and water to neutrality in turn, and vacuum dried to constant weight (vacuum degree of 0.08 MPa, drying temperature of 60 ° C, drying time of 24 h), and after drying, polyphenylene sulfide sodium acetate chelating functional fiber was obtained (compared with before the reaction, the fiber weight increased by 33.7%).

[0060] Embodiment 3:

[0061] The preparation method of the polyphenylene sulfide-based phosphoric acid-type chelating functional fiber of the present invention comprises the following detailed steps:

[0062] a. First, weigh 1g (0.0093mol) of polyphenylene sulfide fiber PPS and add it to the reaction bottle, then add 100mL of 1,2-dichloroethane and let it stand for swelling for 12h. After swelling, add 5.6mL (0.074mol) of dimethoxymethane and 1.38g (0.01mol) of anhydrous aluminum chloride and stir evenly, then heat to 70℃ and react at this temperature for 24h. After the reaction is completed, cool to room temperature, filter and filter out the obtained product, wash the obtained product with anhydrous ethanol, boil it at 50℃ for 5h with 1mol / L HCl solution, wash it with water until it is neutral, and then vacuum dry it to constant weight (vacuum degree is 0.08Mpa, drying temperature is 60℃, and drying time is 24h). After drying, dimethoxymethane cross-linked polyphenylene sulfide fiber is obtained (relative to the original polyphenylene sulfide fiber, the modified fiber has a weight increase of 3.1%).

[0063] b. Add 100 mL of 1,2-dichloroethane to the obtained cross-linked polyphenylene sulfide fiber and let it stand for swelling for 12 hours; then add 10 mL of mixed acid and stir evenly (the mixed acid is prepared by mixing concentrated sulfuric acid and concentrated nitric acid in a molar ratio of 3:1), then heat to 60°C and react at this temperature for 1 hour; after the reaction is completed, cool to room temperature, filter, filter out the obtained product, wash the obtained product with anhydrous ethanol and water in turn until neutral, and vacuum dry to constant weight (vacuum degree is 0.08 MPa, drying temperature is 60°C, and drying time is 24 hours), and obtain modified nitrated PPS-NO2 fiber after drying;

[0064] The obtained modified nitrated PPS-NO2 fiber was placed in 30 mL of 1,2-dichloroethane and allowed to swell for 12 h, and then 2.2 g of stannous chloride as a reducing agent and 40 mL of concentrated hydrochloric acid as a catalyst were added, and the temperature was raised to 90 ° C for reduction reaction for 5 h; after the reaction was completed, it was cooled to room temperature and filtered to obtain the product, and the obtained product was washed with anhydrous ethanol, and then boiled with 1 mol / L hydrochloric acid at 50 ° C for 5 h, and then washed with water until neutral, and vacuum dried to constant weight (vacuum degree of 0.08 MPa, drying temperature of 60 ° C, drying time of 24 h), to obtain amino polyphenylene sulfide fiber PPS-NH2 (compared with before the reaction, the fiber weight increased by 14.9%);

[0065] c. The obtained amino polyphenylene sulfide fiber PPS-NH2 was placed in 110 mL of hydrochloric acid, 6.05 g of phosphorous acid and 2.1 g of trioxymethylene were added, and the temperature was raised to 100 ° C for reaction for 5 hours; after the reaction was completed, it was cooled to room temperature and filtered to obtain the product, and the obtained product was washed with anhydrous ethanol and water to neutrality in turn, and vacuum dried to constant weight (vacuum degree of 0.08 MPa, drying temperature of 60 ° C, drying time of 24 hours), and after drying, polyphenylene sulfide-based phosphoric acid-type chelating functional fiber was obtained (compared with before the reaction, the fiber weight increased by 41.6%).

[0066] Embodiment 4:

[0067] The preparation method of the polyphenylene sulfide-based phosphoric acid-type chelating functional fiber of the present invention comprises the following detailed steps:

[0068] a. First, weigh 1.9g (0.018mol) of polyphenylene sulfide fiber PPS and add it to the reaction bottle, then add 190mL of 1,2-dichloroethane and let it stand for swelling for 12h. After swelling, add 11mL (0.14mol) of dimethoxymethane and 5.3g (0.03mol) of anhydrous aluminum chloride and stir evenly, then heat to 70℃ and react at this temperature for 24h. After the reaction is completed, cool to room temperature, filter and filter out the obtained product, wash the obtained product with anhydrous ethanol, boil it at 50℃ for 5h with 1mol / L HCl solution, wash it with water until it is neutral, and vacuum dry it to constant weight (vacuum degree is 0.08Mpa, drying temperature is 60℃, and drying time is 24h). After drying, dimethoxymethane cross-linked polyphenylene sulfide fiber is obtained (relative to the original polyphenylene sulfide fiber, the modified fiber has a weight increase of 2.8%).

[0069] b. Add 200 mL of 1,2-dichloroethane to the cross-linked polyphenylene sulfide fiber obtained above and let it stand for swelling for 12 hours; then add 20 mL of mixed acid and stir evenly (the mixed acid is prepared by mixing concentrated sulfuric acid and concentrated nitric acid in a molar ratio of 3:1), then heat to 60°C and react at this temperature for 1 hour; after the reaction is completed, cool to room temperature, filter, filter out the obtained product, wash the obtained product with anhydrous ethanol and water in turn until neutral, and vacuum dry to constant weight (vacuum degree is 0.08Mpa, drying temperature is 60°C, and drying time is 24 hours), and obtain modified nitrated PPS-NO2 fiber after drying;

[0070] The modified nitrated PPS-NO2 fiber was placed in 60 mL of 1,2-dichloroethane and allowed to swell for 12 h, and then 5 g of reduced iron powder and 1.5 g of ammonium chloride were added as a reducing agent, and the temperature was raised to 80 ° C for reduction reaction for 3 h; after the reaction, it was cooled to room temperature and filtered to obtain the product, which was washed with anhydrous ethanol, and then boiled with 1 mol / L hydrochloric acid at 50 ° C for 5 h, and then washed with water until neutral, and vacuum dried to constant weight (vacuum degree of 0.08 MPa, drying temperature of 60 ° C, drying time of 24 h), and amino polyphenylene sulfide fiber PPS-NH2 was obtained after drying (compared with before the reaction, the fiber weight increased by 15.5%);

[0071] c. The obtained amino polyphenylene sulfide fiber PPS-NH2 is placed in 200 mL of hydrochloric acid, and then 10 g of phosphorous acid and 4.5 g of trioxymethylene are added, and the temperature is raised to 100 ° C for reaction for 5 hours; after the reaction is completed, it is cooled to room temperature, filtered to obtain the product, and washed with anhydrous ethanol and water to neutrality in turn, and vacuum dried to constant weight (vacuum degree is 0.08 MPa, drying temperature is 60 ° C, and drying time is 24 hours). After drying, polyphenylene sulfide-based phosphoric acid-type chelating functional fiber is obtained (compared with before the reaction, the fiber weight increase is 38.8%).

[0072] Embodiment 5:

[0073] The preparation method of the polyphenylene sulfide-based thiazole type chelating functional fiber of the present invention comprises the following detailed steps:

[0074] a. First, weigh 0.51g (0.0047mol) of polyphenylene sulfide fiber PPS and add it to the reaction bottle, then add 50mL of 1,2-dichloroethane and let it stand for 12h. After swelling, add 3.4mL (0.0376mol) of dimethoxymethane and 2.7g (0.02mol) of anhydrous aluminum chloride and stir evenly, then heat to 70℃ and react at this temperature for 24h. After the reaction is completed, cool to room temperature, filter and filter out the obtained product, wash the obtained product with anhydrous ethanol, boil it at 50℃ for 5h with 1mol / L HCl solution, wash it with water until it is neutral, and vacuum dry it to constant weight (vacuum degree is 0.08Mpa, drying temperature is 60℃, and drying time is 24h). After drying, dimethoxymethane cross-linked polyphenylene sulfide fiber is obtained (relative to the original polyphenylene sulfide fiber, the modified fiber has a weight increase of 2.1%).

[0075] b. Add 50 mL of 1,2-dichloroethane to the obtained cross-linked polyphenylene sulfide fiber and let it stand for swelling for 12 hours; then add 5 mL of mixed acid and stir evenly (the mixed acid is a mixture of concentrated sulfuric acid and concentrated nitric acid in a molar ratio of 3:1), then heat to 60°C, and react at this temperature for 1 hour; after the reaction is completed, cool to room temperature, filter, filter out the obtained product, wash the obtained product with anhydrous ethanol and water in turn until neutral, and vacuum dry to constant weight (vacuum degree is 0.08Mpa, drying temperature is 60°C, and drying time is 24h), and obtain modified nitrated PPS-NO2 fiber after drying;

[0076] The modified nitrated PPS-NO2 fiber was placed in 30 mL of 1,2-dichloroethane and allowed to swell for 12 h, and a reducing agent of 1.1 g of stannous chloride and a catalyst of 22 mL of concentrated hydrochloric acid were added, and the temperature was raised to 90 ° C for a reduction reaction for 5 h; after the reaction, it was cooled to room temperature and filtered to obtain the product, which was washed with anhydrous ethanol, and then boiled with 1 mol / L hydrochloric acid at 50 ° C for 5 h, and then washed with water until neutral, and vacuum dried to constant weight (vacuum degree of 0.08 MPa, drying temperature of 60 ° C, and drying time of 24 h), and amino polyphenylene sulfide fiber PPS-NH2 was obtained after drying (compared with before the reaction, the fiber weight increased by 15.2%);

[0077] c. The obtained amino polyphenylene sulfide fiber PPS-NH2 was placed in 55 mL of 1,2-dichloroethane and allowed to swell for 12 h, and then 4 g of 2-chlorobenzothiazole was added, and the temperature was raised to 100 ° C for reaction for 5 h; after the reaction was completed, it was cooled to room temperature, filtered to obtain the product, and washed with anhydrous ethanol and water to neutrality in turn, and vacuum dried to constant weight (vacuum degree 0.08 MPa, drying temperature 60 ° C, drying time 24 h), and after drying, polyphenylene sulfide-based thiazole-type chelating functional fiber was obtained (compared to before the reaction, the fiber weight increased by 42.9%).

Claims

1. A method for preparing polyphenylene sulfide-based chelate fiber, characterized in that: The preparation method comprises the following steps: a. Add polyphenylene sulfide fiber into a reaction container, then add solvent to fully swell, add crosslinking agent and catalyst after swelling, stir or ultrasonically disperse evenly, then heat to 70-80°C, and react under this temperature condition for 12-48h; after the reaction, cool to room temperature, filter, filter out the obtained product, wash the obtained product with alcohol, boil with acid, wash with water and dry it in sequence to obtain crosslinked polyphenylene sulfide fiber, i.e., crosslinked PPS fiber; b. Add the cross-linked PPS fiber obtained in step a to a solvent to fully swell, add a nitrating agent after swelling, stir or ultrasonically disperse it evenly, then heat it to 40-60° C., and react under this temperature condition for 1-6 hours; after the reaction is completed, cool it to room temperature, filter it, filter out the obtained product, wash the obtained product with alcohol, wash it with water and dry it in turn to obtain modified nitrocellulose PPS-NO2; Place the modified nitrocellulose PPS-NO2 in a container, add a solvent to swell it; then add a reducing agent, heat it to 50-100°C and react for 1-6 hours; after the reaction, cool it to room temperature, filter it, and sequentially wash the product with alcohol, boil it with acid, wash it with water and dry it to obtain amino polyphenylene sulfide fiber PPS-NH2; c. Place the obtained amino polyphenylene sulfide fiber PPS-NH2 in a container and add solvent A; then add functional monomers and heat to 60-120°C for reaction for 4-6 hours; after the reaction is completed, cool to room temperature, filter, and sequentially wash the product with alcohol, water and dry to obtain PPS-based chelated functional fiber, i.e., polyphenylene sulfide-based chelated fiber.

2. The method for preparing polyphenylene sulfide-based chelate fiber according to claim 1, characterized in that: In step a, the mass volume ratio of the polyphenylene sulfide fiber to the solvent is 1 g: 50-100 mL, the molar ratio of the polyphenylene sulfide fiber to the crosslinking agent is 1: 0.5-8, and the molar ratio of the polyphenylene sulfide fiber to the catalyst is 1: 1.2-2.

2.

3. The method for preparing polyphenylene sulfide-based chelate fiber according to claim 1, characterized in that: In step a, the solvent is 1,2-dichloroethane; the catalyst is anhydrous aluminum chloride, anhydrous ferric chloride or anhydrous tin tetrachloride; and the cross-linking agent is at least one of dimethoxymethane, ethylene glycol dimethyl ether and 1,4-dimethoxybenzene.

4. The method for preparing polyphenylene sulfide-based chelate fiber according to claim 1, characterized in that: The specific operation process of sequentially washing the obtained product with alcohol, boiling with acid, washing with water and drying in step a is as follows: the obtained product is sequentially washed with anhydrous ethanol, boiled with a 1-2 mol / L HCl solution at 50° C. for 5-6 h, washed with water until neutral, and then vacuum dried at 50-60° C. to constant weight.

5. The method for preparing polyphenylene sulfide-based chelate fiber according to claim 1, characterized in that: The solvent in step b is 1,2-dichloroethane; the nitrating agent is a mixed acid of concentrated sulfuric acid and concentrated nitric acid, and the molar ratio of concentrated nitric acid to concentrated sulfuric acid is 1:3-7 when mixed; and the reducing agent is stannous chloride or reduced iron powder.

6. The method for preparing polyphenylene sulfide-based chelate fiber according to claim 1, characterized in that: The mass volume ratio of the cross-linked PPS fiber and the solvent added in step b is 1 g: 50-100 mL, and the molar ratio of the cross-linked PPS fiber and the nitrating agent is 1: 0.5-2; The mass volume ratio between the modified nitrocellulose PPS-NO2 and the solvent is 1g:50-100mL, and the mass volume ratio between the modified nitrated PPS-NO2 fiber and the reducing agent is 1:1-5.

7. The method for preparing polyphenylene sulfide-based chelate fiber according to claim 1, characterized in that: The specific process of sequentially washing the obtained product with alcohol, washing with water and drying in step b is: washing the obtained product with anhydrous ethanol in sequence, then washing with water until neutral, and then vacuum drying to constant weight under the conditions of a vacuum degree of 0.08Mpa and a drying temperature of 50 to 60°C; the specific process of sequentially washing the product with alcohol, boiling with acid, washing with water and drying is: washing the obtained product with anhydrous ethanol in sequence, boiling a 1 to 2 mol / L HCl solution at 50°C for 5 to 6h, washing with water until neutral, and then vacuum drying to constant weight under the conditions of a vacuum degree of 0.08Mpa and a drying temperature of 50 to 60°C.

8. The method for preparing polyphenylene sulfide-based chelate fiber according to claim 1, characterized in that: In step c, the mass volume ratio of the amino polyphenylene sulfide fiber PPS-NH2 and the solvent A is 1 g: 50-100 mL, and the molar ratio of the amino polyphenylene sulfide fiber PPS-NH2 and the functional monomer is 1: 1-10.

9. The method for preparing polyphenylene sulfide-based chelate fiber according to claim 1, characterized in that: In step c, the solvent A is 1,2-dichloroethane or hydrochloric acid; and the functional monomer is at least one of sodium chloroacetate, phosphorous acid and 2-chlorobenzothiazole.

10. The method for preparing polyphenylene sulfide-based chelate fiber according to claim 1, characterized in that: The specific process of sequentially washing the product with alcohol, washing with water and drying in step c is as follows: the obtained product is sequentially washed with anhydrous ethanol and washed with water until neutral, and then vacuum dried to constant weight under the conditions of a vacuum degree of 0.08 MPa and a drying temperature of 50-60° C.

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