Plasma synergistic polyvinyl alcohol and glutaraldehyde graft modified PBO (poly (p-phenylene benzobisoxazole)) fiber and preparation method thereof

Abstract

The invention relates to the technical field of PBO fiber modification, in particular to a plasma synergistic polyvinyl alcohol (PVA) and glutaraldehyde (GA) graft modified PBO fiber and a preparation method thereof.The plasma synergistic polyvinyl alcohol (PVA) and glutaraldehyde (GA) graft modified PBO fiber is prepared, a mixed solution prepared through double solvents is adopted to clean dust and oil on the surface of the PBO fiber, clean PBO fiber is prepared, the plasma activated PBO fiber is soaked in an acidic polyvinyl alcohol solution, and the PBO fiber is prepared through a two-step method. According to the preparation method, polyvinyl alcohol macromolecules are uniformly and firmly grafted on the surface of the PBO fiber, hemiacetal reaction of PVA and GA is carried out to generate ether bonds, a compact interfacial film rich in ether bonds is formed, the hydrophilicity of the surface of the GA-coated PVA / PBO fiber is obviously improved, and the surface water contact angle is obviously reduced to 0 degree.

Description

Technical Field

[0001] This invention relates to the field of PBO fiber modification technology, and in particular to a plasma-synergistic grafted polyvinyl alcohol and glutaraldehyde modified PBO fiber and its preparation method. Background Technology

[0002] Poly(p-phenylenebenzodioxazole) (PBO) fibers possess excellent properties such as ultra-high strength and high modulus. However, their high surface crystallinity and lack of polar functional groups lead to chemical inertness, severely restricting fiber / resin interfacial bonding and stress transfer. Common PBO fiber surface modification methods include plasma treatment and grafting. Plasma treatment is essentially a process of high-speed particle "bombardment" and "etching" of the fiber surface. This process, measured in seconds or minutes, can efficiently activate the PBO fiber surface at room temperature. Simultaneously, the plasma treatment process is gentle, with minimal impact on the mechanical properties of the PBO fiber itself, avoiding the strength loss that may occur with traditional chemical methods. However, due to the effects of oxygen, moisture, or other impurities in the air and the occurrence of surface thermodynamic relaxation processes, the interfacial bonding performance of the modified PBO fiber decays over time, thus losing its ability to bond with the resin matrix.

[0003] Chemical grafting modification involves initiating monomer polymerization on the material surface through a chemical reaction, generating graft chains to impart new surface properties without affecting the material's bulk properties. Taking polyvinyl alcohol (PVA) as an example, potassium persulfate or hydrogen peroxide is required to initiate the grafting reaction. The use of initiators makes it difficult to control the grafting reaction rate, resulting in high production costs. Furthermore, residual initiators can disrupt the uniformity of the grafted layer. Therefore, maintaining the surface activity of plasma-modified PBO fibers and overcoming the limitations of initiator use in grafting methods require further exploration by those skilled in the art. Summary of the Invention

[0004] The purpose of this invention is to provide a plasma-modified polyvinyl alcohol (PBO) and glutaraldehyde grafted PBO fiber and its preparation method. The invention utilizes the protonation of hydroxyl groups on the polyvinyl alcohol molecule under acidic conditions to enhance its reaction with the carboxyl groups on the surface of the plasma-treated fiber, thereby achieving uniform grafting of polyvinyl alcohol onto the surface of the PBO fiber. Finally, ether bonds are formed through the acetal reaction of polyvinyl alcohol and glutaraldehyde, which improves the surface polarity of the modified PBO fiber and the interfacial bonding strength with epoxy resin.

[0005] To achieve the above objectives, this invention provides a method for preparing plasma-synergistic polyvinyl alcohol and glutaraldehyde grafted modified PBO fibers, comprising the following steps:

[0006] S1. After cutting the PBO fibers, wash them with deionized water, then soak them in a mixed solution, rinse and dry them to obtain clean PBO fibers.

[0007] S2. Place the clean PBO fibers obtained in S1 into the plasma treatment chamber, and obtain activated PBO fibers after plasma treatment.

[0008] S3. The activated PBO fibers obtained in S2 are soaked in a polyvinyl alcohol (PVA) aqueous solution, and the pH is adjusted to 1-6 using a strong acid to obtain PVA / PBO fibers.

[0009] S4. Immerse the PVA / PBO fibers obtained in S3 in glutaraldehyde (GA) solution, remove them, ultrasonically wash them, and dry them to obtain GA@PVA / PBO fibers.

[0010] Preferably, in S1, the mixed solution is ethanol and methyl ketone mixed in a volume ratio of 1:1, and the soaking time is 1-5 hours.

[0011] More preferably, the soaking time in the polyvinyl alcohol aqueous solution is 2-4 hours; even more preferably, the soaking time is 2.5-3.5 hours.

[0012] Preferably, in S1, the drying temperature is 30-70℃ and the drying time is 0.5-5h.

[0013] More preferably, the drying temperature is 40-65°C and the drying time is 1-4 hours;

[0014] More preferably, the drying temperature is 50-60℃ and the drying time is 2-3 hours.

[0015] Preferably, in S1, the ratio of PBO fiber mass to mixed solution volume is 0.5-100 g / L. More preferably, the ratio is 10-80 g / L; even more preferably, the ratio is 40-60 g / L.

[0016] Preferably, in S2, the vacuum degree of the plasma treatment is 5-100 Pa, the power is 50-300 W, the time is 1-30 min, and the carrier gas is one of compressed air, oxygen, and nitrogen.

[0017] More preferably, the vacuum degree of plasma treatment is 10-50 Pa, the power is 100-200 W, and the time is 1-15 min;

[0018] More preferably, the vacuum degree of the plasma treatment is 15-20 Pa, the power is 120-180 W, and the time is 1-10 min.

[0019] Preferably, in S3, polyvinyl alcohol includes one or more of polyvinyl alcohol type 0588, polyvinyl alcohol type 1788, and polyvinyl alcohol type 2488.

[0020] Preferably, in S3, the strong acid includes one or more of sulfuric acid, hydrochloric acid, and nitric acid.

[0021] Preferably, in step S3, the concentration of the polyvinyl alcohol aqueous solution is 0.01-1 g / mL, and the soaking time is 0.5-4 h. More preferably, the concentration is 0.01-0.5 g / mL, and the soaking time is 1-3 h; even more preferably, the concentration is 0.01-0.25 g / mL, and the soaking time is 1-2 h.

[0022] Preferably, in step S4, the concentration of the glutaraldehyde solution is 0.01-0.1 g / mL, and the soaking time is 0.5-4 h. More preferably, the concentration is 0.02-0.06 g / mL, and the soaking time is 1-3 h. Even more preferably, the concentration is 0.03-0.04 g / mL, and the soaking time is 1-2 h.

[0023] A plasma-modified polyvinyl alcohol and glutaraldehyde grafted PBO fiber, GA@PVA / PBO fiber, is prepared using the aforementioned method for preparing a plasma-modified polyvinyl alcohol and glutaraldehyde grafted PBO fiber.

[0024] Therefore, the present invention provides a plasma-synergistic polyvinyl alcohol and glutaraldehyde grafted modified PBO fiber and its preparation method using the above steps, the beneficial effects of which are:

[0025] 1. This invention uses a mixed solution prepared with two solvents to clean the dust and oil on the surface of PBO fibers, thereby obtaining clean PBO fibers;

[0026] 2. In this invention, PBO fibers are activated by soaking in an acidic polyvinyl alcohol solution, which allows polyvinyl alcohol macromolecules to be uniformly and firmly grafted onto the fiber surface. Polyvinyl alcohol reacts with the hemiacetal of glutaraldehyde to form ether bonds, and a dense interface film rich in ether bonds (COC) is formed on the surface of the modified PBO fibers. The hydrophilicity of the modified PBO fiber surface is significantly improved, and its surface water contact angle is significantly reduced to 0°.

[0027] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0028] Figure 1 This is the infrared spectrum of Embodiment 1 of the present invention;

[0029] Figure 2 This is the infrared spectrum of Comparative Example 1 of the present invention;

[0030] Figure 3 This is the infrared spectrum of Comparative Example 2 of the present invention;

[0031] Figure 4 This is an optical diagram of the contact angle of Embodiment 1 of the present invention;

[0032] Figure 5 This is an optical diagram of the contact angle of Embodiment 2 of the present invention;

[0033] Figure 6 This is an optical diagram of the contact angle of Embodiment 3 of the present invention;

[0034] Figure 7 This is the contact angle optical diagram of Embodiment 4 of the present invention;

[0035] Figure 8 This is an optical diagram of the contact angle of Embodiment 5 of the present invention;

[0036] Figure 9 This is the contact angle optical diagram of Comparative Example 1 of the present invention;

[0037] Figure 10 This is the contact angle optical diagram of Comparative Example 2 of the present invention;

[0038] Figure 11 These are scanning electron microscope images of Embodiment 1 of the present invention;

[0039] Figure 12 These are scanning electron microscope images of Embodiment 2 of the present invention;

[0040] Figure 13 These are scanning electron microscope images of Embodiment 3 of the present invention;

[0041] Figure 14 These are scanning electron microscope images of Embodiment 4 of the present invention;

[0042] Figure 15 These are scanning electron microscope images of Embodiment 5 of the present invention;

[0043] Figure 16 This is a scanning electron microscope image of Comparative Example 1 of the present invention;

[0044] Figure 17 This is a scanning electron microscope image of Comparative Example 2 of the present invention. Detailed Implementation

[0045] The present invention will be further described below with reference to the accompanying drawings and embodiments. Unless otherwise defined, the technical or scientific terms used in this invention should be understood in their ordinary sense by those skilled in the art. The features mentioned above or in the specific examples mentioned in this invention can be combined arbitrarily, and these specific embodiments are only used to illustrate the invention and are not intended to limit the scope of the invention.

[0046] This invention provides a method for preparing plasma-synergistic polyvinyl alcohol and glutaraldehyde grafted modified PBO fibers, comprising the following steps:

[0047] S1. After cutting the PBO fibers, wash them with deionized water to remove dust and soluble impurities adhering to the surface of the PBO fibers. Then soak them in a mixed solution, rinse and dry them to remove the residual mixed solution and dissolved impurities. Dry them to remove the water adsorbed by the PBO fibers and obtain clean PBO fibers.

[0048] S2. Place the clean PBO fibers obtained in S1 into the plasma treatment chamber, and obtain activated PBO fibers after plasma treatment.

[0049] S3. The activated PBO fibers obtained in S2 are soaked in a polyvinyl alcohol aqueous solution, and the pH is adjusted to 1-6 using a strong acid to obtain PVA / PBO fibers.

[0050] S4. Immerse the PVA / PBO fibers obtained in S3 in glutaraldehyde solution, remove them, ultrasonically wash them, and dry them to obtain GA@PVA / PBO fibers.

[0051] In some embodiments of the present invention, in S1, the mixed solution is ethanol and methyl ketone mixed in a volume ratio of 1:1, and the soaking time is 1-5 hours. Using the mixed solution obtained by mixing the two solvents, the polar solubility of ethanol and the weak polar solubility of methyl ketone are utilized to synergistically clean and remove dust and oil from the surface of PBO fibers, preventing impurities from obscuring the active sites on the PBO fiber surface and affecting the subsequent plasma activation effect.

[0052] In some embodiments of the present invention, in S1, the drying temperature is 30-70°C and the drying time is 0.5-5 hours.

[0053] In some embodiments of the present invention, in S1, the ratio of the mass of PBO fiber to the volume of the mixed solution is 0.5-100 g / L.

[0054] In some embodiments of the present invention, in step S2, the vacuum degree of the plasma treatment is 5-100 Pa, the power is 50-300 W, the time is 1-30 min, and the carrier gas is one of compressed air, oxygen, or nitrogen. High-energy particles bombard the fiber surface, breaking down the dense chemical structure and creating a microscopically rough morphology. Through plasma treatment, the carrier gas decomposes into active species in the plasma, reacting with the CH and CC bonds on the PBO fiber surface to introduce oxygen-containing active functional groups such as hydroxyl (-OH) and carboxyl (-COOH).

[0055] In some embodiments of the present invention, in S3, polyvinyl alcohol includes one or more of polyvinyl alcohol type 0588 (degree of polymerization 500), polyvinyl alcohol type 1788 (degree of polymerization 1700), and polyvinyl alcohol type 2488 (degree of polymerization 2400). Polyvinyl alcohol is grafted onto the surface of the PBO fiber by hydrogen bonding or weak chemical bonding between the oxygen-containing active functional groups on the surface of the PBO fiber after plasma activation and the hydroxyl groups (-OH) on the polyvinyl alcohol (PVA) molecular chain.

[0056] In some embodiments of the present invention, in S3, the strong acid includes one or more of sulfuric acid, hydrochloric acid, and nitric acid. Adjusting the pH with a strong acid promotes the dissolution of polyvinyl alcohol and the stretching of its molecular chains, thereby improving grafting uniformity.

[0057] In some embodiments of the present invention, in step S3, the concentration of the polyvinyl alcohol aqueous solution is 0.01-1 g / mL, and the soaking time is 0.5-4 h. Soaking the plasma-activated PBO fibers in an acidic polyvinyl alcohol (PVA) solution allows for uniform and firm grafting of polyvinyl alcohol macromolecules onto the surface of the PBO fibers.

[0058] In some embodiments of the present invention, in step S4, the concentration of the glutaraldehyde solution is 0.01-0.1 g / mL, and the soaking time is 0.5-4 h. Soaking in the glutaraldehyde (GA) solution allows glutaraldehyde (GA), a bifunctional crosslinking agent, to react with the hydroxyl groups (-OH) on the polyvinyl alcohol molecular chain via a condensation reaction (the reaction process is shown below). This crosslinks and solidifies the polyvinyl alcohol molecules grafted onto the PBO surface, forming a stable modified layer and improving the interfacial shear strength (IFSS).

[0059]

[0060] Example 1

[0061] S1. Cut 1g of PBO fiber to 5cm, wash with deionized water, then soak in 50mL of mixed solution (ethanol and methyl ketone mixed in a 1:1 volume ratio) for 3h, rinse with ethanol, and dry in a vacuum oven at 60℃ for 2h to obtain clean PBO fiber.

[0062] S2. Place the clean PBO fibers obtained in S1 into a plasma treatment chamber. The vacuum degree of the plasma treatment is 15 Pa, the power is 130 W, the time is 1 min, and the carrier gas is oxygen. After plasma treatment, activated PBO fibers are obtained.

[0063] S3. Weigh 1g of polyvinyl alcohol 1788 and place it in a water bath. Set the water bath temperature to 95℃ and heat and stir until it is completely dissolved. Add deionized water to obtain a 0.01g / mL polyvinyl alcohol aqueous solution. Soak the activated PBO fiber obtained in S2 in the polyvinyl alcohol aqueous solution for 1 hour. Adjust the pH to 3 using dilute sulfuric acid to obtain polyvinyl alcohol / PBO fiber.

[0064] S4. Take 1g of glutaraldehyde (GA) solution and add it to deionized water to prepare a 0.03g / mL glutaraldehyde solution. Soak the PVA / PBO fiber obtained in S3 in the glutaraldehyde solution for 1h. After taking it out, wash it with ultrasound and dry it to obtain GA@PVA / PBO fiber. The water contact angle of the modified fiber surface is 0°.

[0065] Example 2

[0066] S1. Cut 1g of PBO fiber to 5cm, wash with deionized water, then soak in 50mL of mixed solution (ethanol and methyl ketone mixed in a 1:1 volume ratio) for 3h, rinse with ethanol, and dry in a vacuum oven at 60℃ for 2h to obtain clean PBO fiber.

[0067] S2. Place the clean PBO fibers obtained in S1 into a plasma treatment chamber. The vacuum degree of the plasma treatment is 15 Pa, the power is 100 W, the time is 1 min, and the carrier gas is oxygen. After plasma treatment, activated PBO fibers are obtained.

[0068] S3. Weigh 1g of polyvinyl alcohol 1788 and place it in a water bath. Set the water bath temperature to 95℃ and heat and stir until it is completely dissolved. Add deionized water to obtain a 0.01g / mL polyvinyl alcohol aqueous solution. Soak the activated PBO fiber obtained in S2 in the polyvinyl alcohol aqueous solution for 1 hour. Adjust the pH to 3 using dilute sulfuric acid to obtain PVA / PBO fiber.

[0069] S4. Take 1g of glutaraldehyde (GA) solution and add it to deionized water to prepare a 0.03g / mL glutaraldehyde solution. Soak the PVA / PBO fiber obtained in S3 in the glutaraldehyde solution for 1h. After taking it out, wash it with ultrasound and dry it to obtain GA@PVA / PBO fiber. The water contact angle of the modified fiber surface is 0°.

[0070] Example 3

[0071] S1. Cut 1g of PBO fiber to 5cm, wash with deionized water, then soak in 50mL of mixed solution (ethanol and methyl ketone mixed in a 1:1 volume ratio) for 3h, rinse with ethanol, and dry in a vacuum oven at 60℃ for 2h to obtain clean PBO fiber.

[0072] S2. Place the clean PBO fibers obtained in S1 into a plasma treatment chamber. The vacuum degree of the plasma treatment is 15 Pa, the power is 130 W, the time is 1 min, and the carrier gas is oxygen. After plasma treatment, activated PBO fibers are obtained.

[0073] S3. Weigh 10g of polyvinyl alcohol 1788 and place it in a water bath. Set the water bath temperature to 95℃ and heat and stir until it is completely dissolved. Add deionized water to obtain a 0.1g / mL polyvinyl alcohol aqueous solution. Soak the activated PBO fiber obtained in S2 in the polyvinyl alcohol aqueous solution for 1 hour. Adjust the pH to 3 using dilute sulfuric acid to obtain PVA / PBO fiber.

[0074] S4. Add 1g of glutaraldehyde (GA) solution to deionized water to prepare a 0.03g / mL glutaraldehyde solution. Soak the PVA / PBO fiber obtained in S3 in the glutaraldehyde solution for 1h. After taking it out, ultrasonically wash it and dry it to obtain GA@PVA / PBO fiber. The water contact angle of the modified fiber surface is 101.7°.

[0075] Example 4

[0076] S1. Cut 1g of PBO fiber to 5cm, wash with deionized water, then soak in 50mL of mixed solution (ethanol and methyl ketone mixed in a 1:1 volume ratio) for 3h, rinse with ethanol, and dry in a vacuum oven at 60℃ for 2h to obtain clean PBO fiber.

[0077] S2. Place the clean PBO fibers obtained in S1 into a plasma treatment chamber. The vacuum degree of the plasma treatment is 15 Pa, the power is 130 W, the time is 1 min, and the carrier gas is oxygen. After plasma treatment, activated PBO fibers are obtained.

[0078] S3. Weigh 1g of polyvinyl alcohol 1788 and place it in a water bath. Set the water bath temperature to 95℃ and heat and stir until it is completely dissolved. Add deionized water to obtain a 0.01g / mL polyvinyl alcohol aqueous solution. Soak the activated PBO fiber obtained in S2 in the polyvinyl alcohol aqueous solution for 1 hour. Adjust the pH to 1 using dilute sulfuric acid to obtain PVA / PBO fiber.

[0079] S4. Take 1g of glutaraldehyde (GA) solution and add it to deionized water to prepare a 0.03g / mL glutaraldehyde solution. Soak the PVA / PBO fiber obtained in S3 in the glutaraldehyde solution for 1h. After taking it out, wash it with ultrasound and dry it to obtain GA@PVA / PBO fiber. The water contact angle of the modified fiber surface is 0°.

[0080] Example 5

[0081] S1. Cut 1g of PBO fiber to 5cm, wash with deionized water, then soak in 50mL of mixed solution (ethanol and methyl ketone mixed in a 1:1 volume ratio) for 3h, rinse with ethanol, and dry in a vacuum oven at 60℃ for 2h to obtain clean PBO fiber.

[0082] S2. Place the clean PBO fibers obtained in S1 into a plasma treatment chamber. The vacuum degree of the plasma treatment is 15 Pa, the power is 130 W, the time is 1 min, and the carrier gas is oxygen. After plasma treatment, activated PBO fibers are obtained.

[0083] S3. Weigh 1g of polyvinyl alcohol 1788 and place it in a water bath. Set the water bath temperature to 95℃ and heat and stir until it is completely dissolved. Add deionized water to obtain a 0.01g / mL polyvinyl alcohol aqueous solution. Soak the activated PBO fiber obtained in S2 in the polyvinyl alcohol aqueous solution for 1 hour. Adjust the pH to 3 using dilute sulfuric acid to obtain PVA / PBO fiber.

[0084] S4. Take 10g of glutaraldehyde (GA) solution and add it to deionized water to prepare a 0.01g / mL glutaraldehyde solution. Soak the PVA / PBO fiber obtained in S3 in the glutaraldehyde solution for 1 hour. After taking it out, wash it with ultrasound and dry it to obtain GA@PVA / PBO fiber. The water contact angle of the modified fiber surface is 92.4°.

[0085] Comparative Example 1

[0086] After cutting 1g of PBO fiber to 5cm, wash it with deionized water, then soak it in 50mL of a mixed solution (ethanol and methyl ketone mixed in a 1:1 volume ratio) for 3h. After rinsing with ethanol, dry it in a vacuum oven at 60℃ for 2h to obtain clean PBO fiber.

[0087] Comparative Example 2

[0088] S1. Cut 1g of PBO fiber to 5cm, wash with deionized water, then soak in 50mL of mixed solution (ethanol and methyl ketone mixed in a 1:1 volume ratio) for 3h, rinse with ethanol, and dry in a vacuum oven at 60℃ for 1h to obtain clean PBO fiber.

[0089] S2. Place the clean PBO fibers obtained in S1 into a plasma treatment chamber. The vacuum degree of the plasma treatment is 15 Pa, the power is 130 W, the time is 1 min, and the carrier gas is compressed air. After plasma treatment, activated PBO fibers are obtained.

[0090] Test case

[0091] a. Infrared spectroscopy test

[0092] Infrared spectroscopy tests were performed on the GA@PVA / PBO fibers in Example 1, the PBO fibers in Comparative Example 1, and the activated PBO fibers in Comparative Example 2. The results are as follows: Figures 1-3 As shown. It can be seen that, compared with Comparative Example 1 and Comparative Example 2, Example 1 at 3100cm -1 -3500cm -1 The presence of broad peaks representing hydroxyl groups indicates successful grafting of polyvinyl alcohol onto the fiber surface. Comparative Example 2 showed no significant change in its infrared spectrum compared to Comparative Example 1, indicating that the plasma treatment did not damage the PBO fiber structure.

[0093] b. Water contact angle test

[0094] Contact angle tests were performed on the GA@PVA / PBO fibers in Examples 1-5, the PBO fibers in Comparative Example 1, and the activated PBO fibers in Comparative Example 2. The results are as follows: Figures 4-10 As shown. By Figure 4 , Figure 5 and Figure 7 As can be seen, the GA@PVA / PBO fibers in Examples 1, 2, and 4 exhibit excellent hydrophilicity, with a water contact angle of 0° in all cases. Figure 6 It can be seen that the contact angle of the GA@PVA / PBO fibers in Example 3 is 101.7°. Figure 8 It can be seen that the contact angle of the GA@PVA / PBO fiber in Example 5 is 92.4°. Figure 9 and Figure 10 It can be seen that the water contact angle in Comparative Example 1 is 120.9°, and the water contact angle in Comparative Example 2 is 89.1°.

[0095] A comparison of Examples 1-5 with Comparative Example 1 shows that the hydrophilicity of the modified PBO fibers obtained in Examples 1-5 is improved. A comparison of Examples 1-5 with Comparative Example 2 shows that although Comparative Example 2 exhibits better hydrophilicity immediately after treatment, plasma treatment suffers from poor time-sensitivity. As shown in Table 1, comparing the changes in fiber contact angle over time between Examples 1 and Comparative Example 2, the GA@PVA / PBO fibers prepared in Example 1 maintain surface activity for a longer period compared to Comparative Example 2.

[0096] Table 1. Water contact angle variation over time in Example 1 and Comparative Example 2

[0097] Water contact angle in Example 1 / ° Water contact angle / ° in Comparative Example 2 Week 0 0 89.1 Week 1 0 93.0 Week 2 75.1 95.5 Week 3 79.3 107.6

[0098] c. Scanning electron microscope test

[0099] The surface morphology of the GA@PVA / PBO fibers in Examples 1 and 2 was observed using scanning electron microscopy, and the results are as follows: Figure 11 , Figure 12 As shown, a uniform graft layer forms on the surface of the PBO fibers. (The text abruptly ends here.) Figure 13 It can be seen that excessively high polyvinyl alcohol (PVA) concentrations can lead to excessive accumulation of the grafted layer, which in turn negatively impacts the surface activity of PBO fibers. Figure 14 It can be seen that when the pH of the grafting reaction is too low, the structural integrity of PBO fibers is disrupted. Figure 15 It can be seen that when the glutaraldehyde solution concentration is low, a uniform graft layer cannot be formed on the surface of PBO fibers. (Comparison) Figure 16 , Figure 17 It can be concluded that plasma treatment does not damage the PBO fiber structure.

[0100] Therefore, the present invention employs the above-mentioned plasma-assisted polyvinyl alcohol and glutaraldehyde grafting modification method for PBO fibers. The plasma-activated PBO fibers are soaked in an acidic polyvinyl alcohol solution, which allows polyvinyl alcohol macromolecules to be uniformly and firmly grafted onto the fiber surface. The hemiacetal reaction between PVA and GA generates ether bonds, forming a dense interface film rich in ether bonds (COC) on the surface of the modified PBO fibers. The hydrophilicity of the GA@PVA / PBO fiber surface is significantly improved.

[0101] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for preparing plasma-synergistic polyvinyl alcohol and glutaraldehyde grafted modified PBO fibers, characterized in that: Includes the following steps, S1. After cutting the PBO fibers, wash them with deionized water, then soak them in a mixed solution, rinse and dry them to obtain clean PBO fibers. S2. Place the clean PBO fibers obtained in S1 into the plasma treatment chamber, and obtain activated PBO fibers after plasma treatment. S3. The activated PBO fibers obtained in S2 are soaked in a polyvinyl alcohol aqueous solution, and the pH is adjusted to 1-6 using a strong acid to obtain PVA / PBO fibers. S4. Immerse the PVA / PBO fibers obtained in S3 in glutaraldehyde solution, remove them, ultrasonically wash them, and dry them to obtain GA@PVA / PBO fibers.

2. The method for preparing plasma-synergistic polyvinyl alcohol and glutaraldehyde grafted modified PBO fibers according to claim 1, characterized in that: In S1, the mixed solution is ethanol and methyl ketone mixed in a volume ratio of 1:1, and the soaking time is 1-5 hours.

3. The method for preparing plasma-synergistic polyvinyl alcohol and glutaraldehyde grafted modified PBO fibers according to claim 1, characterized in that: In S1, the drying temperature is 30-70℃ and the drying time is 0.5-5h.

4. The method for preparing plasma-synergistic polyvinyl alcohol and glutaraldehyde grafted modified PBO fibers according to claim 1, characterized in that: In S1, the ratio of PBO fiber mass to mixed solution volume is 0.5-100 g / L.

5. The method for preparing plasma-synergistic polyvinyl alcohol and glutaraldehyde grafted modified PBO fibers according to claim 1, characterized in that: In S2, the vacuum degree of plasma treatment is 5-100Pa, the power is 50-300W, the time is 1-30min, and the carrier gas is one of compressed air, oxygen, or nitrogen.

6. The method for preparing plasma-synergistic polyvinyl alcohol and glutaraldehyde grafted modified PBO fibers according to claim 1, characterized in that: In S3, polyvinyl alcohol includes one or more of the following: polyvinyl alcohol type 0588, polyvinyl alcohol type 1788, and polyvinyl alcohol type 2488.

7. The method for preparing plasma-synergistic polyvinyl alcohol and glutaraldehyde grafted modified PBO fibers according to claim 1, characterized in that: In S3, strong acids include one or more of sulfuric acid, hydrochloric acid, and nitric acid.

8. The method for preparing plasma-synergistic polyvinyl alcohol and glutaraldehyde grafted modified PBO fibers according to claim 1, characterized in that: In S3, the concentration of the polyvinyl alcohol aqueous solution is 0.01-1 g / mL, and the soaking time is 0.5-4 h.

9. The method for preparing plasma-synergistic polyvinyl alcohol and glutaraldehyde grafted modified PBO fibers according to claim 1, characterized in that: In S4, the concentration of glutaraldehyde solution is 0.01-0.1 g / mL, and the soaking time is 0.5-4 h.

10. A plasma-synergistic polyvinyl alcohol and glutaraldehyde grafted modified PBO fiber, characterized in that: GA@PVA / PBO fiber was prepared using a method for preparing plasma-synergistic polyvinyl alcohol and glutaraldehyde grafted modified PBO fiber as described in any one of claims 1-9.

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