High-strength polyester fiber as well as preparation method and application thereof

Abstract

The invention discloses a high-strength polyester fiber as well as a preparation method and application thereof, and relates to the technical field of macromolecular polyester materials. The preparation method comprises the following steps: modifying sepiolite by using hydrazine hydrate to obtain modified sepiolite, modifying polyester chips by using ellagic acid and o-phenylenediamine to obtain modified polyester chips, mixing the modified sepiolite and the modified polyester chips, and carrying out melt spinning and drafting to obtain the high-strength polyester fiber. Wherein the sepiolite is modified by hydrazine hydrate, so that the dispersity of the sepiolite in the polyester fiber can be improved, agglomeration is prevented, and the strength of the polyester fiber is improved. Elagic acid and o-phenylenediamine are adopted to modify polyester chips, so that the interfacial force between the polyester chips and the modified sepiolite can be improved, and the strength of the polyester fiber is improved. According to the invention, sepiolite and polyester chips are adopted as raw materials, and sepiolite and polyester chips are modified at the same time, so that the polyester fiber has a synergistic effect on improving the breaking strength and the breaking elongation of the polyester fiber.

Description

Technical Field

[0001] The present invention relates to the technical field of high-molecular polyester materials, in particular to a high-strength polyester fiber and a preparation method and application thereof. Background Art

[0002] Lifting belts, also known as slings or slings, are devices used for lifting and transportation, usually made of polymer or metal materials. Currently, lifting belts are divided into polypropylene lifting belts, wire rope lifting belts, polyester lifting belts, etc. according to the material. Among them, wire rope lifting belts are made of multiple steel wire ropes woven together, which can easily damage the surface of the hoisted object, and their excessive weight makes them difficult to operate. Although polypropylene lifting belts have the advantages of being light, soft, and non-conductive, they have disadvantages such as easy oxidation, poor dimensional stability, and poor weather resistance. Polyester lifting belts have the advantages of a wide temperature resistance range, high wear resistance and tear strength, and resistance to chemical corrosion. They are widely used in logistics and transportation, construction, chemical and petroleum, and shipbuilding and marine engineering.

[0003] Polyester fiber is a synthetic fiber made from an organic dibasic acid and a diol through a condensation reaction. Although polyester fiber has the advantages of good elasticity, good heat resistance, good stability and good corrosion resistance, its strength cannot meet the high strength requirements of the lifting belt. Therefore, it is necessary to modify or modify the polyester fiber to increase its strength, so as to meet the load-bearing requirements of the polyester fiber for the lifting belt. In the prior art, CN110714237A discloses a method for preparing a highly light nano flame-retardant polyester fiber. By adding nano-sepiolite during the preparation of polyester fiber, the strength of the polyester fiber is improved through the interaction between the sepiolite and the polyester fiber. However, sepiolite is prone to agglomeration. When it is directly mixed with polyester chips, the sepiolite is difficult to be evenly dispersed in the polymer matrix and agglomerates. The agglomerated sepiolite will reduce the interfacial interaction force between it and the polyester, thereby affecting the strength of the polyester fiber.

[0004] Therefore, it is particularly necessary to modify sepiolite as raw material to prepare a high-strength polyester fiber to meet the load-bearing requirements of lifting belts. Summary of the Invention

[0005] In response to the above-mentioned prior art, the present invention aims to provide a high-strength polyester fiber, its preparation method, and application. The present invention utilizes sepiolite and polyester chips as raw materials, modifies the sepiolite with hydrazine hydrate, and modifies the polyester chips with ellagic acid and o-phenylenediamine. The modified sepiolite and modified polyester chips are then blended, melt-spun, and drawn to produce the high-strength polyester fiber. By modifying both the sepiolite and polyester chips, the present invention achieves a synergistic effect in improving the strength of the polyester fiber.

[0006] To achieve the above object, the present invention adopts the following technical solutions: A first aspect of the present invention provides a method for preparing a high-strength polyester fiber, comprising the following steps: (1) Mixing sepiolite powder, hydrazine hydrate and water, heating and reacting, filtering, washing and drying after the reaction is completed, to obtain modified sepiolite; (2) After the ellagic acid solution and the Tris-HCl solution are mixed, the o-phenylenediamine solution is added to react to obtain a mixed solution; the polyester chips are immersed in the mixed solution, taken out and dried to obtain modified polyester chips; (3) After the modified polyester chips, modified sepiolite and compatibilizer are mixed, melt-spinning and drawing are carried out to obtain high-strength polyester fibers.

[0007] Preferably, in step (1), the mass ratio of sepiolite powder, hydrazine hydrate and water is (6-8):3:(10-15).

[0008] Preferably, in step (1), the heating temperature is 50-80°C and the reaction time is 1-3h.

[0009] Preferably, in step (1), the drying temperature is 50-70°C and the drying time is 24-48 hours.

[0010] Preferably, in step (2), the pH of the Tris-HCl solution is 8-9.

[0011] Preferably, in step (2), the concentration of the ellagic acid solution is 0.5-1.0 g / L, and the concentration of the o-phenylenediamine solution is 0.5-1.0 g / L.

[0012] Preferably, in step (2), the volume ratio of the ellagic acid solution, the Tris-HCl solution and the o-phenylenediamine solution is (12-16):5:(8-12).

[0013] Preferably, in step (2), the reaction time is 10-20 min.

[0014] Preferably, in step (2), the polyester chips are immersed in the mixed solution for 12-24 hours.

[0015] Preferably, in step (2), the drying temperature is 70-80°C and the drying time is 12-24 hours.

[0016] Preferably, in step (3), the compatibilizer is silane coupling agent KH-570.

[0017] Preferably, in step (3), the mass ratio of the modified polyester chips, the modified sepiolite and the compatibilizer is 100:(10-20):(0.5-1.5).

[0018] Preferably, in step (3), during the melt spinning process, the spinning speed is 12-20 m / s and the temperature is 250-280°C; during the drawing process, the drawing ratio is 3.5-4.5 and the drawing temperature is 70-90°C.

[0019] The second aspect of the present invention provides high-strength polyester fibers prepared by the above preparation method.

[0020] A third aspect of the present invention provides use of the high-strength polyester fiber in preparing a lifting belt.

[0021] Beneficial effects of the present invention: The present invention adopts hydrazine hydrate to modify sepiolite to obtain modified sepiolite, then adopts ellagic acid and o-phenylenediamine to modify polyester chips to obtain modified polyester chips, finally after the modified sepiolite and modified polyester chips are mixed, through melt spinning and drafting, high-strength polyester fiber is obtained. Wherein, adopting hydrazine hydrate to modify sepiolite can improve the dispersibility of sepiolite in polyester fiber, prevent agglomeration, thereby improving the strength of polyester fiber. Adopting ellagic acid and o-phenylenediamine to modify polyester chips can improve the interfacial force between polyester chip and modified sepiolite, thereby improving the strength of polyester chip finally obtained. The present invention adopts sepiolite and polyester chips as raw materials, and sepiolite and polyester chips are simultaneously modified, and have a synergistic effect on improving the breaking strength and elongation at break of polyester fiber. DETAILED DESCRIPTION

[0022] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present application belongs.

[0023] In order to enable those skilled in the art to more clearly understand the technical solution of the present invention, the technical solution of the present invention will be described in detail below with reference to specific embodiments.

[0024] The experimental materials used in the examples of the present invention are all conventional experimental materials in the art and can be purchased through commercial channels.

[0025] In the present invention, sepiolite was purchased from Neixiang County Hongyang Sepiolite Co., Ltd., the CAS number of hydrazine hydrate is 10217-52-4, the CAS number of ellagic acid is 476-66-4, the CAS number of o-phenylenediamine is 615-28-1, KH-570 was purchased from Shandong Ruifeng New Materials Co., Ltd., and polyester chips were purchased from Sinopec Yizheng Chemical Fiber Co., Ltd.

[0026] Example 1: (1) Sepiolite powder, hydrazine hydrate and water were mixed in a mass ratio of 7:3:14, heated to 70°C for 2 h, and filtered after the reaction was completed. The filtered solid was collected, washed with distilled water three times, and dried at 60°C for 48 h to obtain modified sepiolite; (2) After mixing 0.8 g / L ellagic acid solution and Tris-HCl solution with a pH of 8.5, 0.8 g / L o-phenylenediamine solution was added and reacted for 15 minutes to obtain a mixed solution, wherein the mass ratio of ellagic acid solution, Tris-HCl solution and o-phenylenediamine solution was 14:5:10; after immersing polyester chips in the mixed solution for 24 hours, the chips were taken out and dried at 75°C for 24 hours to obtain modified polyester chips; (3) The modified polyester chips, modified sepiolite and KH-570 are mixed in a mass ratio of 100:15:1, and then melt-spun and drawn to obtain high-strength polyester fibers; In the melt spinning process, the spinning speed is 15 m / s and the temperature is 260°C; in the drawing process, the drawing ratio is 4 and the drawing temperature is 80°C.

[0027] Example 2: (1) Mix sepiolite powder, hydrazine hydrate and water in a mass ratio of 6:3:10, heat to 50°C and react for 3 hours. After the reaction is completed, filter and collect the filtered solid, wash it with distilled water three times, and dry it at 50°C for 24 hours to obtain modified sepiolite; (2) After mixing 0.5 g / L ellagic acid solution and Tris-HCl solution with a pH of 8, 0.5 g / L o-phenylenediamine solution was added and reacted for 20 minutes to obtain a mixed solution, wherein the mass ratio of ellagic acid solution, Tris-HCl solution and o-phenylenediamine solution was 12:5:12; after immersing polyester chips in the mixed solution for 24 hours, the chips were taken out and dried at 70°C for 24 hours to obtain modified polyester chips; (3) The modified polyester chips, modified sepiolite and KH-570 were mixed in a mass ratio of 100:10:0.5, and then melt-spun and drawn to obtain high-strength polyester fibers; In the melt spinning process, the spinning speed is 12 m / s and the temperature is 250°C; in the drawing process, the drawing ratio is 3.5 and the drawing temperature is 80°C.

[0028] Example 3: (1) Mix sepiolite powder, hydrazine hydrate and water in a mass ratio of 8:3:15, heat to 80°C and react for 1 hour. After the reaction is completed, filter and collect the filtered solid, wash it with distilled water three times, and dry it at 70°C for 24 hours to obtain modified sepiolite; (2) After mixing 1.0 g / L ellagic acid solution and Tris-HCl solution with a pH of 9, 1.0 g / L o-phenylenediamine solution was added and reacted for 10 minutes to obtain a mixed solution, wherein the mass ratio of ellagic acid solution, Tris-HCl solution and o-phenylenediamine solution was 16:5:12; after immersing polyester chips in the mixed solution for 24 hours, the chips were taken out and dried at 80°C for 12 hours to obtain modified polyester chips; (3) The modified polyester chips, modified sepiolite and KH-570 are mixed in a mass ratio of 100:20:1.5, and then melt-spun and drawn to obtain high-strength polyester fibers; In the melt spinning process, the spinning speed is 20 m / s and the temperature is 280°C; in the drawing process, the drawing ratio is 4.5 and the drawing temperature is 90°C.

[0029] Comparative Example 1: This comparative example uses unmodified polyester chips to prepare polyester fibers. The specific steps are: Polyester chips and KH-570 are mixed in a mass ratio of 100:1, and then melt-spun and stretched to obtain high-strength polyester fibers. During the melt spinning process, the spinning speed is 15 m / s and the temperature is 260°C; during the stretching process, the stretching ratio is 4 and the stretching temperature is 80°C.

[0030] Comparative Example 2: This comparative example uses unmodified polyester chips and modified sepiolite to prepare polyester fibers. The specific steps are: Polyester chips, modified sepiolite and KH-570 are mixed in a mass ratio of 100:15:1, and then melt-spun and stretched to obtain high-strength polyester fibers. In the melt-spinning process, the spinning speed is 15 m / s and the temperature is 260°C; in the stretching process, the stretching ratio is 4 and the stretching temperature is 80°C.

[0031] The preparation method of the modified sepiolite is the same as that in Example 1.

[0032] Comparative Example 3: This comparative example uses modified polyester chips to prepare polyester fibers. The specific steps are: The modified polyester chips and KH-570 were mixed at a mass ratio of 100:1, and then melt-spun and stretched to obtain high-strength polyester fibers. During the melt spinning process, the spinning speed was 15 m / s and the temperature was 260°C; during the stretching process, the stretching ratio was 4 and the stretching temperature was 80°C.

[0033] The preparation method of the modified polyester chips is the same as that in Example 1.

[0034] Test Example 1: The mechanical properties of the polyester fibers prepared in Examples 1-3 and Comparative Examples 1-3 were tested with reference to GB / T 14344-2003 Test Method for Tensile Properties of Synthetic Fiber Filaments. The results are shown in Table 1.

[0035] Table 1 As shown in Table 1, the polyester fibers produced according to the present invention have a breaking strength of 9.6-10.2 cN / dtex and an elongation at break of 14.2-16.5%. Compared to polyester fibers produced using only unmodified polyester chips (Comparative Example 1), the polyester fibers produced using unmodified polyester chips and modified sepiolite (Comparative Example 2) have a breaking strength increase of 0.8 cN / dtex and a breaking elongation increase of 2.2%. The polyester fibers produced using only modified polyester chips (Comparative Example 3) have a breaking strength increase of 1.6 cN / dtex and a breaking elongation increase of 2.9%. The polyester fibers produced according to the present invention using modified polyester chips and modified sepiolite have a breaking strength increase of 5.0-5.6 cN / dtex and a breaking elongation increase of 7.3-9.6%. This demonstrates that the simultaneous modification of sepiolite and polyester chips in the present invention has a synergistic effect in improving the breaking strength and elongation of polyester fibers.

[0036] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A method for preparing high-strength polyester fiber, characterized in that: The following steps are involved: (1) Mixing sepiolite powder, hydrazine hydrate and water, heating and reacting, filtering, washing and drying after the reaction is completed, to obtain modified sepiolite; (2) After mixing the ellagic acid solution and the Tris-HCl solution, add the o-phenylenediamine solution and react to obtain a mixed solution; immerse the polyester chips in the mixed solution, take out and dry them to obtain modified polyester chips; (3) After the modified polyester chips, modified sepiolite and compatibilizer are mixed, melt-spinning and drawing are carried out to obtain high-strength polyester fibers.

2. The method for preparing high-strength polyester fiber according to claim 1, wherein: In step (1), the mass ratio of sepiolite powder, hydrazine hydrate and water is (6-8):3:(10-15).

3. The method for preparing high-strength polyester fiber according to claim 1, wherein: In step (1), the heating temperature is 50-80°C and the reaction time is 1-3 hours; the drying temperature is 50-70°C and the drying time is 24-48 hours.

4. The method for preparing high-strength polyester fiber according to claim 1, wherein: In step (2), the pH of the Tris-HCl solution is 8-9, the concentration of the ellagic acid solution is 0.5-1.0 g / L, and the concentration of the o-phenylenediamine solution is 0.5-1.0 g / L.

5. The method for preparing high-strength polyester fiber according to claim 1, wherein: In step (2), the volume ratio of ellagic acid solution, Tris-HCl solution and o-phenylenediamine solution is (12-16):5:(8-12).

6. The method for preparing high-strength polyester fiber according to claim 1, wherein: In step (2), the reaction time is 10-20 minutes; the polyester chips are immersed in the mixed solution for 12-24 hours.

7. The method for preparing high-strength polyester fiber according to claim 1, wherein: In step (3), the compatibilizer is a silane coupling agent KH-570, and the mass ratio of the modified polyester chips, the modified sepiolite and the compatibilizer is 100: (10-20): (0.5-1.5).

8. The method for preparing high-strength polyester fiber according to claim 1, wherein: In step (3), during the melt spinning process, the spinning speed is 12-20 m / s and the temperature is 250-280°C; during the drawing process, the drawing ratio is 3.5-4.5 and the drawing temperature is 70-90°C.

9. The high-strength polyester fiber prepared by the preparation method according to any one of claims 1 to 8.

10. Use of the high-strength polyester fiber according to claim 9 in the preparation of lifting belts.

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