A polyacrylonitrile pre-oxidized fiber fabric and its production process

Abstract

The present invention belongs to the technical field of fabric production, and in particular relates to a polyacrylonitrile pre-oxidized fiber fabric and its production process. Among them, a production process of a polyacrylonitrile pre-oxidized fiber fabric includes the following production steps: S1 fiber mixing → S2 pretreatment → S3 opening → S4 carding → S5 drawing → S6 drawing treatment → S7 roving → S8 spinning → S9 doubling → S10 twisting → S11 weaving; The raw materials used in S1 fiber mixing include 50-60 parts by weight of pre-oxidized fiber, 10-15 parts of flame-retardant viscose fiber, and 15-25 parts of flame-retardant polyester fiber; The drawn sliver obtained after S5 drawing is impregnated with a drawing treatment solution containing polyvinyl alcohol, and the polyvinyl alcohol penetrates between the fibers of the drawn sliver, so that the pre-oxidized fiber has better synchronism with the viscose fiber and the flame-retardant polyester fiber during the production process, reducing the number of broken ends generated by the pre-oxidized fiber, and thus enhancing the breaking strength of the polyacrylonitrile pre-oxidized fiber fabric.

Description

Technical Field

[0001] The present invention belongs to the technical field of fabric production, and particularly relates to a polyacrylonitrile pre-oxidized fiber fabric and a production process thereof. Background Art

[0002] Polyacrylonitrile pre-oxidized fiber, also known as pre-oxidized fiber or pre-oxygen fiber for short, is a black fiber with a partially cyclized structure formed by air oxidation of polyacrylonitrile fiber. It has high flame retardancy, excellent thermal stability, does not melt, soften and shrink, or have melt droplets during combustion, and belongs to a quasi-non-combustible product; and it has the advantages of good heat insulation effect, resistance to acid and alkali corrosion, resistance to chemical environment, and good radiation resistance.

[0003] After polyacrylonitrile fiber is pre-oxidized, it endows the fiber with excellent flame retardancy and heat resistance; however, after polyacrylonitrile fiber is pre-oxidized, it shows brittleness and low strength, resulting in a high breakage rate during the textile process, and the mechanical properties of the pre-oxidized fiber fabric are poor. Summary of the Invention

[0004] In order to improve the problem of poor mechanical properties of polyacrylonitrile pre-oxidized fiber fabric, the present application provides a polyacrylonitrile pre-oxidized fiber fabric and a production process thereof.

[0005] In the first aspect, the present application provides a production process of a polyacrylonitrile pre-oxidized fiber fabric, adopting the following technical scheme:

[0006] A production process of a polyacrylonitrile pre-oxidized fiber fabric includes the following production steps:

[0007] S1 Fiber mixing → S2 Pretreatment → S3 Opening → S4 Carding → S5 Drawing → S6 Drawing treatment → S7 Roving → S8 Spinning → S9 Doubling → S10 Twisting → S11 Weaving;

[0008] The raw materials used in the S1 fiber mixing include 50 - 60 parts by weight of pre-oxidized fiber, 10 - 15 parts by weight of flame-retardant viscose fiber, and 15 - 25 parts by weight of flame-retardant polyester fiber;

[0009] The S2 pretreatment is to impregnate the mixed fiber obtained in the S1 step with a pretreatment mixed solution, and the pretreatment mixed solution includes 24 - 36 parts by weight of random polyether, 12 - 24 parts by weight of alkylolamide, 12 - 24 parts by weight of chitosan quaternary ammonium salt, and 270 - 330 parts by weight of water;

[0010] The S6 drawing treatment is to impregnate the drawn sliver obtained in the S5 step with a drawing treatment solution, and the drawing treatment solution includes 6 - 10 parts by weight of polyvinyl alcohol and 90 - 110 parts by weight of water.

[0011] By adopting the above technical solution, pre-oxidized fibers, flame-retardant viscose fibers and flame-retardant polyester fibers are blended. The abundant hydroxyl groups on the flame-retardant viscose fibers provide room for modification of the blended yarn. The excellent mechanical properties of the flame-retardant polyester fibers improve the mechanical properties of the blended yarn and fabric. After blending, the properties of the three fibers synergistically enhance the spinnability of the pre-oxidized fibers and solve the problem of poor mechanical properties of the pre-oxidized fiber fabric.

[0012] The random polyether, alkylolamide and random polyether are used in combination to reduce the friction between the pre-oxidized fibers, flame-retardant viscose fibers and flame-retardant polyester fibers and increase the conductivity and spinnability of the blended fibers.

[0013] The drawn sliver obtained after S5 is impregnated with the drawing treatment liquid. The polyvinyl alcohol in the drawing treatment liquid penetrates between the fibers of the drawn sliver. The polyvinyl alcohol and the hydroxyl groups on the fibers of the drawn sliver synergistically act to have better synchronism between the pre-oxidized fibers, viscose fibers and flame-retardant polyester fibers when subjected to external forces during the textile process, reducing the number of broken ends of the pre-oxidized fibers caused by friction or external forces during the textile process, and thus increasing the breaking strength of the polyacrylonitrile pre-oxidized fiber fabric.

[0014] Optionally, the pretreatment mixture further includes 12 - 24 parts by weight of a smoothing agent, and the smoothing agent is at least one of pentaerythritol monostearate, pentaerythritol tetrastearate and natural mineral oil.

[0015] By adopting the above technical solution, by adding a smoothing agent to the pretreatment mixture, the smoothing agent can further reduce the friction force suffered by the pre-oxidized fibers during the production process. When used in combination with the random polyether, alkylolamide and chitosan quaternary ammonium salt, it improves the conductivity, smoothness and bundling property of the three fibers, further reducing the number of broken ends of the pre-oxidized fibers caused by friction or external forces during the textile process, and increasing the breaking strength of the polyacrylonitrile pre-oxidized fiber fabric.

[0016] Optionally, in the step S2, the mixed fibers are impregnated in the pretreatment mixture at 30 °C for 10 - 17 h.

[0017] By adopting the above technical solution, by setting the impregnation time and temperature, the pre-oxidized fibers, flame-retardant viscose fibers and flame-retardant polyester fibers are fully immersed in the pretreatment mixture, making the three fibers have good conductivity, bundling property, smoothness and spinnability.

[0018] Optionally, the drawing treatment liquid further includes 3 - 14 parts by weight of polydimethylsiloxane, 5 - 17 parts of nonylphenol polyoxyethylene ether and 1 - 6 parts of pentaerythritol monostearate.

[0019] By adopting the above technical solution, in the drawing treatment liquid, the pentaerythritol monostearate with a relatively small molecular weight can migrate to the fiber or the drawn sliver during the processing process and form an outer surface of a film layer on the drawn sliver, thereby reducing the frictional force between the drawn sliver and the processing equipment; the polydimethylsiloxane, nonylphenol polyoxyethylene ether and pentaerythritol monostearate in the drawing treatment liquid further enhance the smoothness between the three fibers in the drawn sliver; thereby reducing the number of broken ends generated during the production of the polyacrylonitrile pre-oxidized fiber, and thereby increasing the breaking strength of the polyacrylonitrile pre-oxidized fiber fabric.

[0020] Optionally, the temperature of the drawing treatment liquid in the S6 drawing treatment step is 20-40 °C.

[0021] By adopting the above technical solution, setting the appropriate treatment temperature of the drawing treatment liquid enables the drawing treatment liquid to fully penetrate into the drawn sliver obtained in S5. If the temperature of the drawing treatment liquid is too low, the viscosity of the drawing treatment liquid is high, making it impossible for the drawing treatment liquid to fully penetrate into the drawn sliver obtained after drawing; if the temperature of the drawing treatment liquid is too high, the polyvinyl alcohol binds too quickly to the surface of the drawn sliver obtained after drawing, preventing the polyvinyl alcohol from further penetrating into the interior of the drawn sliver obtained after drawing, and the drawing treatment liquid cannot fully penetrate into the drawn sliver obtained after drawing, resulting in poor treatment effect of the drawing treatment liquid.

[0022] Optionally, the twist of the roving in the S7 roving spinning is 4-8 twists / 10 cm.

[0023] By adopting the above technical solution, if the twist of the roving is too low, the synergistic effect between the fibers is poor and the mechanical properties of the roving are poor; if the twist of the roving is too high, the number of broken ends of the fibers increases and the breaking strength of the fabric becomes poor.

[0024] Preferably, the twist of the yarn in the S8 yarn spinning is 100-200 twists / 10 cm.

[0025] By adopting the above technical solution, if the twist of the yarn is too low, the mechanical strength of the fabric is low, and if the twist is too high, the pre-oxidized fiber is prone to breakage and the mechanical strength of the fabric will also decrease; after the drawn sliver obtained by S5 drawing is treated by S6 drawing, the synchronism and synergism of the three fibers in the drawn sliver when subjected to external forces are increased, the frictional force between the fibers and between the fibers and the equipment is reduced, thereby reducing the number of broken ends generated by the pre-oxidized fiber during the textile process, and thereby enabling a higher twist of the yarn to be set in the S8 yarn spinning, and thereby enhancing the breaking strength of the polyacrylonitrile pre-oxidized fiber yarn and fabric.

[0026] Preferably, the twist of the ply yarn in the S10 ply twisting is 75-95 twists / 10 cm.

[0027] By adopting the above technical solution, the twist of the ply yarn is increased, so that the synergistic effect between the yarns is increased and the mechanical properties of the fabric are increased. However, if the twist of the ply yarn is too large, the handle of the fabric will deteriorate.

[0028] Optionally, the environmental humidity during the textile process of the polyacrylonitrile pre-oxidized fiber fabric is 45%-85%.

[0029] By adopting the above technical solution, the humidity is maintained at 45%-85%, and the antistatic agents in the S2 pretreatment liquid and the S6 drawing liquid are formulated, reducing the static electricity generation between the fibers, the drawn sliver and the yarns, so that the flame-retardant viscose fiber and the flame-retardant polyester fiber maintain good holding and synergistic effects with the pre-oxidized fiber, reducing the number of broken ends generated by the polyacrylonitrile pre-oxidized fiber during the production process, and further enhancing the breaking strength of the polyacrylonitrile pre-oxidized fiber yarn and the fabric.

[0030] In a second aspect, the present application provides a polyacrylonitrile pre-oxidized fiber fabric, adopting the following technical solution:

[0031] A polyacrylonitrile pre-oxidized fiber fabric is prepared by using the production process of any one of the polyacrylonitrile pre-oxidized fiber fabrics described in the present application.

[0032] By adopting the above technical solution, the prepared polyacrylonitrile pre-oxidized fiber fabric has excellent mechanical properties.

[0033] In summary, the present application has the following beneficial effects:

[0034] 1. The pre-oxidized fiber, the flame-retardant viscose fiber and the flame-retardant polyester fiber are blended. The rich hydroxyl groups on the flame-retardant viscose fiber provide room for modification of the blended yarn. The excellent mechanical properties of the flame-retardant polyester fiber improve the mechanical properties of the blended yarn and the fabric. After blending, the properties of the three fibers synergistically enhance the spinnability of the pre-oxidized fiber and the mechanical properties of the pre-oxidized fiber and the pre-oxidized fiber fabric.

[0035] 2. The combined use of random polyether, alkylolamide, chitosan quaternary ammonium salt and smoothing agent improves the poor bundling property and conductivity of the pre-oxidized fiber and the smoothness between the three fibers after blending, thereby improving the spinnability of the pre-oxidized fiber and the mechanical properties of the pre-oxidized fiber and the pre-oxidized fiber fabric.

[0036] 3. The drawn sliver obtained after drawing is impregnated with a drawing treatment liquid containing polyvinyl alcohol. The polyvinyl alcohol penetrates between the fibers of the drawn sliver and synergistically interacts with the hydroxyl groups on the fibers of the drawn sliver, enabling the pre-oxidized fiber to have better synchrony and synergistic effect with the viscose fiber and the flame-retardant polyester fiber during the textile process. The drawing treatment liquid formulates and optimizes the twist of the roving, the yarn and the ply yarn, reducing the number of broken ends generated by the pre-oxidized fiber during the textile process and enhancing the mechanical properties of the blended yarn and the polyacrylonitrile pre-oxidized fiber fabric. Detailed implementation mode

[0037] Raw materials: Viscose fiber (1.5d * 38), pre-oxidized fiber (1.5d * 38), flame-retardant polyester fiber (1.5d * 38), alkylolamide (CAS: 68603-42-9, trade name: YS-6502, amine value ≤ 100), chitosan quaternary ammonium salt (CAS: 70694-72-3, substitution degree ≥ 90%), lauric acid random polyether LPE-1200 (molecular weight: about 1200), isomeric tridecanol random polyether TPE-1000 (molecular weight: about 1000), cetylstearyl alcohol phosphate (CAS: 911408-50-9), pentaerythritol monostearate (molecular weight: 402), pentaerythritol tetrastearate (molecular weight: 1200), natural mineral oil (CAS: 8020-83-5), coconut oil amide propyl betaine CAS: 61789-40-0), polydimethylsiloxane (CAS: 9016-00-6), nonylphenol polyoxyethylene ether (CAS: 14409-72-4, hydroxyl value: 101-109mgKOH / g), polyvinyl alcohol (CAS: 9002-89-5, average molecular weight: 110,000-130,000, alcoholysis degree: 87.0-89.0%), isomeric tridecanol ether phosphate (potassium salt) (model: E-1310P).

[0038] Examples

[0039] A production process of a polyacrylonitrile pre-oxidized fiber fabric, specifically using the raw materials shown in Table 1, including the following production steps: S1 Fiber mixing → S2 Pretreatment → S3 Opening → S4 Carding → S5 Drawing → S6 Drawing treatment → S7 Roving → S8 Spinning → S9 Doubling → S10 Twisting → S11 Weaving.

[0040] S1 Fiber mixing: Mix the pre-oxidized fiber, flame-retardant viscose fiber and flame-retardant polyester fiber to obtain a mixed fiber;

[0041] S2 Pretreatment:

[0042] Use the pretreatment mixed solution to impregnate the mixed pre-oxidized fiber, flame-retardant viscose fiber and flame-retardant polyester fiber at 30°C for 10h, and then drain the pre-oxidized fiber, flame-retardant viscose fiber and flame-retardant polyester fiber.

[0043] The pretreatment mixed solution is a mixed solution of lauric acid random polyether, alkylolamide, chitosan quaternary ammonium salt and water.

[0044] S3 Opening: Put the pre-oxidized fiber, flame-retardant viscose fiber and flame-retardant polyester fiber after S2 pretreatment into an opener for opening treatment.

[0045] S4 Carding:

[0046] The mixed fibers after opening in S2 are processed by the blow-carding unit of the carding machine to obtain a sliver, with a fiber layer weight per unit area of 200 g / m 2 , and the delivery speed is 80 m / min.

[0047] S5 Drawing:

[0048] Six slivers are drawn on a drawframe to obtain a roving. The delivery speed of the first draw is 300 m / min, the delivery speed of the last draw is 230 m / min, and the total draft ratio is 4 times.

[0049] S6 Drawing Treatment:

[0050] Before spinning the roving into the coarse yarn, the roving is impregnated with a drawing treatment liquid by an oil wheel. The drawing treatment liquid is a mixture of polyvinyl alcohol and water, and the temperature of the mixed liquid is 20 °C.

[0051] S7 Coarse Yarn:

[0052] The draft ratio of the back zone is 1.10, the total draft ratio is set to 4.5 times, and the twist of the coarse yarn is 4 turns / 10 cm.

[0053] S8 Fine Yarn:

[0054] The conveying speed of the coarse yarn is controlled at 4.2 m / s, the feeding sliver gauge is 6 mm, and the twist of the fine yarn obtained is 100 turns / 10 cm.

[0055] S9 Twisting Together / S10 Twisting:

[0056] After spinning, two fine yarns are plied on a fine yarn testing machine. The ply yarn is S-twist, and the twist of the ply yarn after plying is 75 turns / 10 cm, and the fineness is about 37 tex.

[0057] S11 Weaving:

[0058] Using the yarn after S10 twisting as the raw material, a fabric is woven on a knitting machine. The fabric is twill weave, and the weight per unit area of the fabric is about 185 g / m 2 .

[0059] In the above-mentioned textile environment from S1 to S11, the humidity is 45%.

[0060] Example 2-3

[0061] A production process of a polyacrylonitrile pre-oxidized fiber fabric, which is different from Example 1 in that in S1 fiber mixing, the set weights of the modified viscose fiber, pre-oxidized fiber and flame-retardant polyester fiber are different; in S2 pretreatment, the set weights of lauric acid random polyether, alkylolamide, chitosan quaternary ammonium salt and water in the pretreatment mixed liquid are different; in S6 drawing treatment, the set weights of polyvinyl alcohol and water in the drawing treatment liquid are different, as shown in Table 1 specifically:

[0062] Table 1 List of fiber compositions, compositions of the pretreatment mixture, and composition parameters of the drawing treatment liquid in Examples 1 - 3

[0063]

[0064]

[0065] Examples 4 - 8

[0066] A production process of a polyacrylonitrile pre - oxidized fiber fabric, different from Example 1 in that: the pretreatment mixture further includes a smoothing agent, and among Examples 4 - 8, the types and weight settings of the smoothing agent in the pretreatment mixture are different, as specifically shown in Table 2.

[0067] Table 2 List of type and weight setting parameters of the smoothing agent in Examples 4 - 8

[0068]

[0069] Examples 9 - 12

[0070] A production process of a polyacrylonitrile pre - oxidized fiber fabric, different from Example 1 in that: the impregnation time for the mixed fibers to be impregnated with the pretreatment mixture in the S2 pretreatment is set differently, as specifically shown in Table 3:

[0071] Table 3 List of impregnation time parameters for S2 pretreatment in Examples 9 - 12 and Example 1

[0072] S2 Pretreatment Example 1 Example 9 Example 10 Example 11 Example 12 Impregnation time / h 10 11 13 15 17

[0073] Examples 13 - 17

[0074] A production process of a polyacrylonitrile pre - oxidized fiber fabric, different from Example 1 in that: the drawing treatment liquid further includes polydimethylsiloxane, nonylphenol polyoxyethylene ether, and pentaerythritol monostearate, and the weight settings of polydimethylsiloxane, nonylphenol polyoxyethylene ether, and pentaerythritol monostearate and the temperature setting of the drawing treatment liquid in Examples 13 - 17 are specifically shown in Table 4:

[0075] Table 4 List of weight settings of polydimethylsiloxane, nonylphenol polyoxyethylene ether, and pentaerythritol monostearate in the drawing treatment liquid and temperature setting parameters of the drawing treatment liquid in Examples 13 - 17

[0076] Classification Example 13 Example 14 Example 15 Example 16 Example 17 Polydimethylsiloxane / kg 14 5 10 12 3 Nonylphenol polyoxyethylene ether / kg 17 14 11 8 5 Pentaerythritol monostearate / kg 1 2 4 5 6 Drawing treatment liquid / ℃ 20 35 30 25 40

[0077] Examples 18 - 21

[0078] A production process of a polyacrylonitrile pre-oxidized fiber fabric, which is different from that of Example 1 in that: the twist setting of the medium yarn spun in S7 coarse yarn spinning is different, as specifically shown in Table 5:

[0079] Table 5 Parameter list of the twist of the medium yarn spun in S7 coarse yarn spinning in Examples 18 - 21 and Example 1

[0080] Classification Example 1 Example 18 Example 19 Example 20 Example 21 Roving twist / 10cm 4 5 6 7 8

[0081] Examples 22 - 25

[0082] A production process of a polyacrylonitrile pre-oxidized fiber fabric, which is different from that of Example 1 in that: the twist setting of the fine yarn spun in S8 fine yarn spinning is different, as specifically shown in Table 6:

[0083] Table 6 Parameter list of the twist of the fine yarn spun in S8 fine yarn spinning in Examples 22 - 25 and Example 1

[0084] Classification Example 1 Example 22 Example 23 Example 24 Example 25 Yarn twist / 10cm 100 130 150 180 200

[0085] Examples 26 - 29

[0086] A production process of a polyacrylonitrile pre-oxidized fiber fabric, which is different from that of Example 1 in that: the twist setting of the ply yarn in S10 twisting is different, as specifically shown in Table 7:

[0087] Table 7 Parameter list of the twist of the ply yarn in S10 twisting in Examples 26 - 29 and Example 1

[0088] S10 Twisting Example 1 Example 26 Example 27 Example 28 Example 29 Ply twist / 10cm 75 80 85 90 95

[0089] Examples 30 - 33

[0090] A production process of a polyacrylonitrile pre-oxidized fiber fabric, which is different from that of Example 1 in that: the environmental humidity setting is different during the textile process of the polyacrylonitrile pre-oxidized fiber fabric, as specifically shown in Table 8:

[0091] Table 8 Parameter list of the environmental humidity during the textile process of the polyacrylonitrile pre-oxidized fiber fabric in Examples 30 - 33 and Example 1

[0092]

[0093]

[0094] Example 34

[0095] A production process of a polyacrylonitrile pre-oxidized fiber fabric, which is different from that of Example 1 in that: in the pretreatment mixture, isomeric tridecyl alcohol random polyether is replaced with lauric acid random polyether in equal amount.

[0096] Comparative example

[0097] Comparative Example 1

[0098] A production process of a polyacrylonitrile pre-oxidized fiber fabric, which is different from Example 1 in that: the polyacrylonitrile pre-oxidized fiber fabric does not contain flame-retardant viscose fiber and flame-retardant polyester fiber.

[0099] Comparative Example 2

[0100] A production process of a polyacrylonitrile pre-oxidized fiber fabric, which is different from Example 1 in that: the polyacrylonitrile pre-oxidized fiber fabric does not contain flame-retardant viscose fiber, and the production step of S6 drawing is not set.

[0101] Comparative Example 3

[0102] A production process of a polyacrylonitrile pre-oxidized fiber fabric, which is different from Example 1 in that: the production step of S6 drawing is not set in the production process of the polyacrylonitrile pre-oxidized fiber fabric, and the twist of the roving in S8 roving spinning is 105 turns / 10 cm.

[0103] Performance detection test

[0104] 1. Tensile strength: Referring to GB / T3923.1-2013 "Textiles - Tensile properties of fabrics - Part 1: Determination of maximum force and elongation at maximum force (strip method)", the tensile strength of the polyacrylonitrile pre-oxidized fiber fabrics produced in Examples 1-34 and Comparative Examples 1-3 was measured on an electronic fabric strength tester. Each fabric specimen was measured 3 times in parallel, and the test results were averaged. The test results are shown in Table 9.

[0105] Table 9 Tensile strength test results of polyacrylonitrile pre-oxidized fiber fabrics produced in Examples 1-34 and Comparative Examples 1-3

[0106]

[0107]

[0108] Combining Examples 1-34 and Comparative Examples 1-3 and referring to Table 9, it can be seen that:

[0109] The warp tensile strength of the polyacrylonitrile pre-oxidized fiber fabrics produced in Examples 1-34 is in the range of 483-502 N, and the weft tensile strength is in the range of 466-485 N;

[0110] The warp breaking strength of the polyacrylonitrile pre-oxidized fiber fabric produced in Comparative Examples 1-3 ranges from 465 to 473 N, and the weft breaking strength ranges from 443 to 457 N, indicating that in this application, the use of flame-retardant viscose fiber and flame-retardant polyester fiber blended with the polyacrylonitrile pre-oxidized fiber fabric, as well as the production process of setting S2 pretreatment and S6 drawing process, and optimizing the twist of the yarn and the environmental humidity during the textile process, to a certain extent overcome the problem of poor mechanical properties of the polyacrylonitrile pre-oxidized fiber fabric caused by brittleness, low strength and high end-breakage rate of polyacrylonitrile fiber during the textile process, so that the produced polyacrylonitrile pre-oxidized fiber fabric has good mechanical properties.

[0111] It can be seen from Examples 4-8 and Example 1 in combination with Table 9 that:

[0112] The warp breaking strength of the polyacrylonitrile pre-oxidized fiber fabric produced in Examples 4-8 ranges from 490 to 502 N, and the weft breaking strength ranges from 475 to 485 N;

[0113] The warp breaking strength of the polyacrylonitrile pre-oxidized fiber fabric produced in Example 1 is 483 N, and the weft breaking strength ranges from 468 N, indicating that adding a smoothing agent to the pretreatment mixture can enhance the warp breaking strength and weft breaking strength of the polyacrylonitrile pre-oxidized fiber fabric, probably because the smoothing agent can reduce the friction between fibers and between fibers and equipment during the processing of pre-oxidized fibers. It can be seen from the experimental results that when pentaerythritol monostearate is used in combination with natural mineral oil, the warp breaking strength and weft breaking strength of the polyacrylonitrile pre-oxidized fiber fabric are relatively high, probably because pentaerythritol monostearate and natural mineral oil have good compatibility with random polyether, alkylolamide and chitosan quaternary ammonium salt, enhancing the conductivity and smoothness of pre-oxidized fiber, flame-retardant viscose fiber and flame-retardant polyester fiber, reducing the static electricity generated during the textile process of pre-oxidized fiber and weakening the friction force received by pre-oxidized fiber, thereby reducing the number of broken ends generated and increasing the breaking strength of the polyacrylonitrile pre-oxidized fiber fabric.

[0114] It can be seen from Examples 13-17, Example 1 and Comparative Example 2 in combination with Table 9 that:

[0115] The warp breaking strength of the polyacrylonitrile pre-oxidized fiber fabric produced in Examples 13-17 ranges from 491 to 502 N, and the weft breaking strength ranges from 476 to 486 N;

[0116] The warp breaking strength of the polyacrylonitrile pre-oxidized fiber fabric produced in Example 1 is 483 N, and the weft breaking strength is in the range of 468 N, indicating that the polydimethylsiloxane, nonylphenol polyoxyethylene ether, pentaerythritol monostearate, polyvinyl alcohol and the pretreatment mixture in the drawing treatment liquid act synergistically to enhance the synchronism of the three fibers in the drawn sliver obtained in Step S5 when subjected to external forces and the smoothness between the fibers. At the same time, the frictional force between the drawn sliver obtained in Step S5 and the processing equipment is reduced, the adhesion between the polyvinyl alcohol in the drawing treatment liquid and the processing equipment is reduced, and the number of broken ends generated during the production of the polyacrylonitrile pre-oxidized fiber is reduced, thereby increasing the breaking strength of the polyacrylonitrile pre-oxidized fiber fabric.

[0117] Combined with Examples 22-25, Example 1 and Comparative Example 3 and combined with Table 9, it can be seen that:

[0118] The warp breaking strength of the polyacrylonitrile pre-oxidized fiber fabric produced in Examples 22-25 and Example 1 is in the range of 483-502 N, and the weft breaking strength is in the range of 468-487 N;

[0119] The warp breaking strength of the polyacrylonitrile pre-oxidized fiber fabric produced in Comparative Example 3 is 473 N, and the weft breaking strength is in the range of 457 N, indicating that the drawn sliver obtained in Step S5 treated with the S6 drawing treatment liquid can be set with a higher twist of the spun yarn without causing the fracture of the polyacrylonitrile pre-oxidized fiber, thereby enhancing the breaking strength of the polyacrylonitrile pre-oxidized fiber yarn and fabric.

[0120] This specific embodiment is only an interpretation of the present application, and it is not a limitation of the present application. Those skilled in the art can make modifications to this embodiment without creative contributions according to needs after reading this specification, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A production process of a polyacrylonitrile pre-oxidized fiber fabric, characterized in that, It includes the following production steps: S1 Fiber mixing → S2 Pretreatment → S3 Opened → S4 Carding → S5 Drawing → S6 Drawing treatment → S7 Roving → S8 Spinning → S9 Twisting → S10 Twisting → S11 Weaving; The raw materials used in the S1 fiber mixing include 50 - 60 parts by weight of pre - oxidized fiber, 10 - 15 parts of flame - retardant viscose fiber, and 15 - 25 parts of flame - retardant polyester fiber; The S2 pretreatment is to impregnate the mixed fiber obtained in the S1 step with a pretreatment mixture. The pretreatment mixture includes 24 - 36 parts by weight of random polyether, 12 - 24 parts of alkylolamide, 12 - 24 parts of chitosan quaternary ammonium salt, 12 - 24 parts of smoothing agent, and 270 - 330 parts of water. The smoothing agent is at least one of pentaerythritol monostearate, pentaerythritol tetrastearate, and natural mineral oil. The mixed fiber is impregnated in the pretreatment mixture and the impregnation time is 10 - 17 h at 30°C; The S6 drawing treatment is to impregnate the drawn sliver obtained in the S5 step with a drawing treatment liquid. The drawing treatment liquid includes 6 - 10 parts by weight of polyvinyl alcohol, 3 - 14 parts of polydimethylsiloxane, 5 - 17 parts of nonylphenol polyoxyethylene ether, 1 - 6 parts of pentaerythritol monostearate, and 90 - 110 parts of water. The temperature of the drawing treatment liquid in the S6 drawing treatment step is 20 - 40°C; In the S7 roving spinning, the twist of the roving is 4 - 8 turns / 10 cm; in the S8 spinning, the twist of the yarn is 100 - 200 turns / 10 cm; in the S10 twisting, the twist of the ply yarn is 75 - 95 turns / 10 cm; the environmental humidity during the textile process of the polyacrylonitrile pre - oxidized fiber fabric is 45% - 85%.

2. A polyacrylonitrile pre-oxidized fiber fabric, characterized in that, It is prepared by using the production process of a polyacrylonitrile pre - oxidized fiber fabric described in Claim 1.

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