Continuous surface modification method for PBO fabric

Abstract

The invention relates to the field of PBO fabric surface modification, and provides a continuous surface modification method for a PBO fabric. According to the method, construction of a gallic acid (GA) polyphenol layer is promoted through normal-pressure low-temperature plasma, and a taurine hydrophilic group is introduced for surface modification of the PBO fabric. The method comprises the following steps: firstly, cleaning and drying a PBO fabric, then carrying out on-line activation on the fabric by utilizing plasmas, and immersing the fabric into a GA system within 0-30 seconds after plasma treatment, so that a polyphenol layer is formed on the surface of the fabric by GA; and finally, immersing the fabric into a taurine solution, so that taurine is fixed on the surface of the polyphenol layer through a quinone-amine reaction and a Michael addition reaction, and washing, drying and curing to obtain the modified PBO fabric. The process can be continuous, the wettability of the PBO fabric can be remarkably improved, the interfacial compatibility with a resin material is enhanced, and the shear strength of the composite material is improved.

Description

Technical Field

[0001] This invention relates to the field of surface modification technology for high-performance fiber fabrics, and more specifically to a continuous surface modification method for PBO fabrics. Background Technology

[0002] Poly(p-phenylenebenzodioxazole) (PBO) materials possess excellent properties such as high strength, high modulus, heat resistance, and flame retardancy, and can be used as reinforcements in composite materials after being woven into fabrics. However, PBO has few surface functional groups, strong chemical inertness, and low surface energy, resulting in insufficient wettability and interfacial compatibility with matrices such as resins. This leads to composite materials being prone to interfacial debonding and interlayer delamination failures under load and humid and hot environments.

[0003] Atmospheric pressure low-temperature plasma treatment can rapidly introduce polar groups and increase roughness at room temperature, but the activation effect decays over time, and plasma treatment alone is difficult to construct a long-lasting chemical reaction layer. While mussel-inspired systems such as polydopamine can provide a universal adhesive layer, they are costly and have limited publicly available information. Natural polyphenols, such as gallic acid (GA), are widely available, inexpensive, and environmentally friendly. They can undergo oxidative polymerization / self-assembly deposition under alkaline and oxidative conditions to form polyphenol layers, and can also act as "linkers" to undergo quinone-amine reactions and Michael addition reactions with amine-containing compounds, thereby achieving further functionalization.

[0004] In the prior art, various surface modification schemes have been proposed to improve the interfacial bonding between PBO fibers / fabrics and the resin matrix, as detailed in the following prior art solutions: 1) Chinese patent CN103088624B discloses a method for low-temperature plasma surface modification of PBO fibers under normal pressure, providing process parameters such as input power, discharge voltage, frequency, and processing time (in seconds), and emphasizing that the process is short and can be carried out continuously online. This scheme mainly improves the surface properties of fibers through plasma bombardment / active particle action, but its technical route still focuses on plasma "single-step activation" and does not involve rapid coating of activation sites with low-cost coatings after plasma treatment, nor does it involve the synergistic design for continuous fabric deposition and subsequent retention of hydrophilic / reactive groups.

[0005] 2) Chinese patent CN102808325B discloses a method for surface modification of PBO fibers. This method employs a pretreatment process involving hydrogen peroxide and enzymes (with added ultrasound) to introduce hydroxyl coupling agents into the surface, thereby introducing different active functional groups to meet the needs of various thermosetting resins. This scheme belongs to a wet chemical oxidation / enzymatic system combined with coupling agent condensation. The process and chemical system differ from the short-term continuous fabrication methods, and it does not involve the construction of the deposition layer after atmospheric pressure plasma deposition.

[0006] 3) Chinese patent CN120138972A discloses a method for modifying the surface of PBO fibers by plasma treatment with a synergistic copolymer coating: first, plasma treatment is performed, then a monomer solution containing a photoinitiator is coated, and free radical polymerization is initiated by ultraviolet irradiation to form a copolymer coating on the fiber surface. This method has a more complex process chain and equipment configuration; at the same time, its polymerization coating route is different from the low-cost green system of "rapid deposition of natural polyphenols plus taurine functionalization" used in this application.

[0007] However, the aforementioned existing technologies still have at least the following shortcomings: First, plasma activation alone or activation-based schemes often lack a synergistic mechanism for immediate coating of activation sites with a low-cost, rapid deposition layer after activation, making it difficult to balance short-term and long-term stability; Second, although combinations such as polydopamine are effective, they are widely disclosed and have high costs and system complexity, which is not conducive to forming green, low-cost, and easily sustainable differentiated routes; Third, some wet chemical routes have long process chains and insufficient adaptability to continuous fabric processing.

[0008] Therefore, it is necessary to provide a continuous and stable method for modifying PBO fabrics to improve the interfacial properties and durability of PBO fabrics in composite materials. Summary of the Invention

[0009] In view of this, the present invention provides a surface modification method for PBO fabrics suitable for continuous production, in order to solve problems such as poor surface wettability of PBO fabrics, poor interfacial compatibility, low interfacial shear strength of composite materials, and short plasma activation aging.

[0010] To achieve the above objectives, the present invention adopts the following technical solution: A continuous surface modification method for PBO fabrics includes the following steps: S1. Clean and dry the PBO fabric to obtain a clean PBO fabric. S2. The clean PBO fabric described in S1 is passed through the plasma jet treatment zone in a continuous feeding manner and fed under compressed air conditions to obtain activated PBO fabric. S3. After passing the activated PBO fabric described in S2 through the plasma treatment zone, immerse it in the gallic acid (GA) aqueous system within 0-30s to form a GA polyphenol layer, thereby obtaining a polyphenol layer / PBO fabric. S4. Immerse the polyphenol layer / PBO fabric described in S3 in a taurine aqueous solution to obtain a taurine-functionalized polyphenol layer / PBO fabric. S5. The fabric obtained in S4 is washed and dried to obtain the modified PBO fabric.

[0011] Furthermore, in step S1, the PBO fabric can be either PBO warp and weft fabric or PBO UD fabric.

[0012] Furthermore, the cleaning method involves rinsing with deionized water followed by cleaning with an organic solvent, repeated three times. The organic solvent is one or a combination of ethanol and acetone. The drying temperature is 60-120℃, and the drying time is 4-8 hours.

[0013] Furthermore, the low-temperature plasma in S2 is a plasma jet.

[0014] Furthermore, in S2, the fabric feeding speed is 5-25m / min, and the processing width is 20cm-200cm.

[0015] Furthermore, in S3, the concentration of gallic acid (GA) is 0.5-5 g / L, the pH of the polyphenol deposition system is 8.0-9.5, the temperature is 20-60℃, and the immersion time is 0.5-5 min.

[0016] Furthermore, in S4, the taurine concentration is 2-5 g / L, the pH is 8.0-9.0, the temperature is 20-60℃, and the immersion time is 1-10 min.

[0017] Furthermore, in step S5, the drying process employs hot air and / or infrared radiation, with a drying temperature of 60-120℃ and a drying time of 10-20 minutes.

[0018] Compared to existing technologies, the present invention combines online plasma activation with rapid GA deposition, allowing the activated fabric to enter the GA system within 0-30 seconds after passing through the plasma treatment zone. This helps suppress the decay of the activation effect over time and promotes the construction of the polyphenol layer, resulting in a more stable surface reaction layer. Using the GA polyphenol layer as an intermediate linker to bind taurine, it is fixed to the polyphenol layer surface through quinone-amine reaction and Michael addition, introducing stable hydrophilic groups and significantly improving the wettability and interfacial compatibility of PBO fabrics. The process is continuous, has mild conditions, and is easy to scale up, making it suitable for online processing on continuous fabric production lines, thereby improving the interfacial shear strength and service durability of PBO fabrics in composite materials. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0020] Figure 1 This is a water contact angle diagram of the modified PBO fabric in Embodiment 1 of the present invention; Figure 2 This is a water contact angle diagram of the modified PBO fabric in Embodiment 2 of the present invention; Figure 3 This is a water contact angle diagram of the modified PBO fabric in Embodiment 3 of the present invention; Figure 4 This is a water contact angle diagram of the modified PBO fabric in Embodiment 4 of the present invention; Figure 5 This is a water contact angle diagram of the modified PBO fabric in Embodiment 5 of the present invention; Figure 6 This is a water contact angle diagram of the modified PBO fabric in Comparative Example 1 of the present invention. Figure 7 This is a water contact angle diagram of the modified PBO fabric in Comparative Example 2 of the present invention; Figure 8 This is a water contact angle diagram of the modified PBO fabric in Comparative Example 3 of the present invention. Figure 9 This is a water contact angle diagram of the PBO fabric after cleaning in Comparative Example 4 of the present invention. Detailed Implementation

[0021] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] This invention provides a continuous surface modification method for PBO fabrics, comprising the following steps: Step (1): Clean and dry the PBO fabric to obtain a clean PBO fabric. The cleaning method is to clean with deionized water and then with organic solvent to remove oil stains and auxiliary agent residues on the fabric surface before drying. The drying temperature is 60-120℃. The organic solvent is one or a combination of ethanol and acetone. The drying temperature is 70-110℃.

[0023] Step (II): The clean PBO fabric from Step (I) is continuously fed through an atmospheric pressure low-temperature plasma treatment zone for surface activation to obtain activated PBO fabric. The atmospheric pressure low-temperature plasma is a plasma jet, the fabric feeding speed is 5-25 m / min, and the treatment width is 20-200 cm. More preferably, the fabric feeding speed is 8-20 m / min and the treatment width is 30-150 cm.

[0024] Step (3): After the PBO fabric activated in step (2) is passed through the plasma treatment zone, it is immersed in the GA (gallic acid) aqueous system within 0-30s to form a GA polyphenol layer, resulting in a polyphenol layer / PBO fabric; the concentration of GA is 0.5-5g / L, the pH of the polyphenol deposition system is 8.0-9.5, and the temperature is 20-60℃; more preferably, the concentration of GA is 1-4g / L, the pH of the polyphenol deposition system is 8.3-9.2, and the temperature is 25-55℃; the time from when the activated fabric leaves the plasma treatment zone to when it enters the GA system is 0-30s.

[0025] Step (iv): Immerse the polyphenol layer / PBO fabric from step (iii) in an alkaline solution of taurine to fix the taurine onto the surface of the polyphenol layer through a quinone-amine reaction and Michael addition, thereby obtaining a taurine-functionalized polyphenol layer / PBO fabric; the taurine concentration is 2-5 g / L, the pH is 8.0-9.0, and the temperature is 20-60℃; more preferably, the taurine concentration is 2.5-4.5 g / L, the pH is 8.2-8.8, and the temperature is 25-55℃.

[0026] Step (5): Wash the fabric obtained in step (4) and dry it at 60-120℃ for 10-20 min to obtain the modified PBO fabric. Washing is done with deionized water to remove unfixed GA / taurine and weak adsorbents. Drying is done with hot air, infrared or a combination thereof, at a temperature of 60-120℃ for 10-20 min; more preferably, the drying temperature is 70-110℃ for 12-18 min.

[0027] The optimal continuous surface modification method for PBO fabrics described above includes the following: the organic solvent is a combination of ethanol and acetone; the drying temperature is 80-100℃; the fabric feeding speed is 10-15 m / min; the treatment width is 50-120 cm; the GA concentration is 2-3 g / L; the pH of the polyphenol deposition system is 8.5-9.0; and the temperature is 30-50℃. The time for the activated fabric to enter the GA system after leaving the plasma treatment zone is 0-10 s. The taurine concentration is 3-4 g / L; the pH is 8.4-8.7; and the temperature is 30-50℃. The drying temperature is 80-100℃; and the drying time is 15-18 min.

[0028] This invention provides a continuous surface modification method for PBO fabrics, comprising the following steps: Example 1 Step (1): Take the PBO warp and weft fabric, wash it with deionized water, then wash it with ethanol, wash it a total of 3 times, and dry it at 80℃ to obtain clean PBO fabric.

[0029] Step (2): The clean PBO fabric is continuously passed through the plasma jet treatment zone under compressed air conditions at a speed of 10 m / min and a treatment width of 50 cm to obtain activated PBO fabric.

[0030] Step (3): After the activated fabric leaves the plasma treatment zone, it enters the GA aqueous system 30 seconds later. The GA concentration is 0.5 g / L, pH is 8.6, and the temperature is 40℃. A GA polyphenol layer is formed, resulting in a polyphenol layer / PBO fabric.

[0031] Step (4): Immerse the polyphenol layer / PBO fabric in a taurine aqueous solution with a taurine concentration of 3 g / L, pH 8.5, and a temperature of 40°C. After the reaction, the taurine-functionalized polyphenol layer / PBO fabric is obtained.

[0032] Step (5): After washing with deionized water, dry at 90℃ for 15 minutes to obtain modified PBO fabric.

[0033] Example 2 Step (1): Take PBO UD fabric, wash it with deionized water, then wash it with ethanol, and dry it at 80°C to obtain clean PBO fabric.

[0034] Step (2): The clean PBO fabric is continuously passed through the plasma jet treatment zone under compressed air conditions at a speed of 5 m / min and a treatment width of 100 cm to obtain activated PBO fabric.

[0035] Step (3): 15s after leaving the plasma treatment zone, enter the GA system with a GA concentration of 2g / L, pH 8.5, and temperature of 30℃ to form a GA polyphenol layer and obtain a polyphenol layer / PBO fabric.

[0036] Step (4): Immerse the polyphenol layer / PBO fabric in a taurine aqueous solution with a taurine concentration of 2 g / L, pH 8.3, and a temperature of 30°C. After the reaction, a taurine-functionalized polyphenol layer / PBO fabric is obtained.

[0037] Step (5): After washing with deionized water, dry at 80℃ for 12 minutes to obtain modified PBO fabric.

[0038] Example 3 Step (1): Take PBO UD fabric, wash it with deionized water, then wash it with ethanol, and dry it at 60°C to obtain clean PBO fabric.

[0039] Step (2): The clean PBO fabric is continuously passed through the plasma jet treatment zone under compressed air conditions at a speed of 12m / min and a treatment width of 200cm to obtain activated PBO fabric.

[0040] Step (3): After leaving the plasma treatment zone, enter the GA system 5s later. The GA concentration is 1g / L, pH is 8.5, and the temperature is 30℃ to form a GA polyphenol layer, thus obtaining a polyphenol layer / PBO fabric.

[0041] Step (4): Immerse the polyphenol layer / PBO fabric in a taurine aqueous solution with a taurine concentration of 4 g / L, pH 8.3, and a temperature of 30°C. After the reaction, a taurine-functionalized polyphenol layer / PBO fabric is obtained.

[0042] Step (5): After washing with deionized water, dry at 80℃ for 15 minutes to obtain modified PBO fabric.

[0043] Example 4 Step (1): Take PBO warp and weft fabric, wash it with deionized water, then wash it with ethanol, and dry it at 80°C to obtain clean PBO fabric.

[0044] Step (2): The clean PBO fabric is continuously passed through the plasma jet treatment zone under compressed air conditions at a speed of 25 m / min and a treatment width of 200 cm to obtain activated PBO fabric.

[0045] Step (3): After leaving the plasma treatment zone, enter the GA system for 10 seconds. The GA concentration is 1 g / L, pH is 8.5, and the temperature is 30℃ to form a GA polyphenol layer, thus obtaining a polyphenol layer / PBO fabric.

[0046] Step (4): Immerse the polyphenol layer / PBO fabric in a taurine aqueous solution with a taurine concentration of 5 g / L, pH 8.0, and a temperature of 20°C. After the reaction, the taurine-functionalized polyphenol layer / PBO fabric is obtained.

[0047] Step (5): After washing with deionized water, dry at 120℃ for 12 minutes to obtain modified PBO fabric.

[0048] Example 5 Step (1): Take PBO UD fabric, wash it with deionized water, then wash it with ethanol, and dry it at 60°C to obtain clean PBO fabric.

[0049] Step (2): The clean PBO fabric is continuously passed through the plasma jet treatment zone under compressed air conditions at a speed of 5 m / min and a treatment width of 200 cm to obtain activated PBO fabric.

[0050] Step (3): After leaving the plasma treatment zone, enter the GA system for 10 seconds. The GA concentration is 5 g / L, pH is 9.5, and the temperature is 60℃ to form a GA polyphenol layer, thus obtaining a polyphenol layer / PBO fabric.

[0051] Step (4): Immerse the polyphenol layer / PBO fabric in a taurine aqueous solution with a taurine concentration of 2 g / L, pH 8.0, and a temperature of 55°C. After the reaction, a taurine-functionalized polyphenol layer / PBO fabric is obtained.

[0052] Step (5): After washing with deionized water, dry at 120℃ for 10 minutes to obtain modified PBO fabric.

[0053] Comparative Example 1 Step (1): Take PBO UD fabric, wash it with deionized water, then wash it with ethanol, and dry it at 80°C to obtain clean PBO fabric.

[0054] Step (2): Immerse the clean PBO fabric in the GA system with a GA concentration of 2g / L, pH 8.5, and temperature of 30℃ to form a GA polyphenol layer, thus obtaining a polyphenol layer / PBO fabric.

[0055] Step (3): Immerse the polyphenol layer / PBO fabric in a taurine aqueous solution with a taurine concentration of 2 g / L, pH 8.3, and a temperature of 30°C. After the reaction, the taurine-functionalized polyphenol layer / PBO fabric is obtained.

[0056] Step (4): After washing with deionized water, dry at 80℃ for 12 minutes to obtain modified PBO fabric.

[0057] Comparative Example 2 Step (1): Take PBO UD fabric, wash it with deionized water, then wash it with ethanol, and dry it at 80°C to obtain clean PBO fabric.

[0058] Step (2): The clean PBO fabric is continuously passed through the plasma jet treatment zone under compressed air conditions at a speed of 25 m / min and a treatment width of 100 cm to obtain activated PBO fabric.

[0059] Step (3): After leaving the plasma treatment zone, enter the GA system for 60 seconds. The GA concentration is 2g / L, pH is 8.5, and the temperature is 30℃ to form a GA polyphenol layer, thus obtaining a polyphenol layer / PBO fabric.

[0060] Step (4): Immerse the polyphenol layer / PBO fabric in a taurine aqueous solution with a taurine concentration of 2 g / L, pH 8.3, and a temperature of 30°C. After the reaction, a taurine-functionalized polyphenol layer / PBO fabric is obtained.

[0061] Step (5): After washing with deionized water, dry at 80℃ for 12 minutes to obtain modified PBO fabric.

[0062] Comparative Example 3 Step (1): Take PBO UD fabric, wash it with deionized water, then wash it with ethanol, and dry it at 80°C to obtain clean PBO fabric.

[0063] Step (2): The clean PBO fabric is continuously passed through the plasma jet treatment zone under compressed air conditions at a speed of 30 m / min and a treatment width of 200 cm to obtain activated PBO fabric.

[0064] Step (3): After leaving the plasma treatment zone, enter the GA system for 30 seconds. The GA concentration is 0.1 g / L, pH is 7.5, and the temperature is 30℃ to form a GA polyphenol layer, thus obtaining a polyphenol layer / PBO fabric.

[0065] Step (4): Immerse the polyphenol layer / PBO fabric in a taurine aqueous solution with a taurine concentration of 0.5 g / L, pH 10, and temperature of 20°C. After the reaction, the taurine-functionalized polyphenol layer / PBO fabric is obtained.

[0066] Step (5): After washing with deionized water, dry at 150℃ for 10 minutes to obtain modified PBO fabric.

[0067] Comparative Example 4 After washing the PBO warp and weft fabric with deionized water, it is then washed with ethanol and dried at 60°C to obtain a clean PBO fabric.

[0068] The samples prepared in Examples 1-5 and Comparative Examples 1-2 were tested according to GB / T42694-2023 "Detection and evaluation of surface anti-wetting properties of textiles - contact angle and roll-off angle method". The results are shown in Table 1.

[0069] Table 1 Comparison of water droplet angle data between Examples 1-5 and Comparative Examples 1-2

[0070] The data comparison in Table 1 shows that the PBO fabric modified by the method used in this scheme has a significantly reduced water droplet angle and spreads completely within 30 seconds.

[0071] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0072] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A continuous surface modification method for PBO fabrics, characterized in that, Includes the following steps: S1. Clean and dry the PBO fabric to obtain a clean PBO fabric. S2. The clean PBO fabric described in S1 is passed through the plasma jet treatment zone in a continuous feeding manner and fed under compressed air conditions to obtain activated PBO fabric. S3. After passing the activated PBO fabric described in S2 through the plasma treatment zone, immerse it in the gallic acid (GA) aqueous system within 0-30s to form a GA polyphenol layer, thereby obtaining a polyphenol layer / PBO fabric. S4. Immerse the polyphenol layer / PBO fabric described in S3 in a taurine aqueous solution to obtain a taurine-functionalized polyphenol layer / PBO fabric. S5. The fabric obtained in S4 is washed and dried to obtain the modified PBO fabric.

2. The continuous surface modification method for PBO fabrics according to claim 1, characterized in that, In step S1, the PBO fabric can be either PBO warp and weft fabric or PBO UD fabric.

3. The continuous surface modification method for PBO fabrics according to claim 1, characterized in that, The cleaning method involves rinsing with deionized water followed by rinsing with an organic solvent, repeated three times. The organic solvent is one or a combination of ethanol and acetone. The drying temperature is 60-120℃, and the drying time is 4-8 hours.

4. The continuous surface modification method for PBO fabrics according to claim 1, characterized in that, The plasma in S2 is a plasma jet.

5. The continuous surface modification method for PBO fabric according to claim 1, characterized in that, In S2, the fabric feeding speed is 5-25m / min, and the processing width is 20cm-200cm.

6. The continuous surface modification method for PBO fabric according to claim 1, characterized in that, The concentration of gallic acid (GA) in S3 is 0.5-5 g / L, the pH of the polyphenol deposition system is 8.0-9.5, the temperature is 20-60℃, and the immersion time is 0.5-5 min.

7. The continuous surface modification method for PBO fabrics according to claim 1, characterized in that, The taurine concentration in S4 is 2-5 g / L, the pH is 8.0-9.0, the temperature is 20-60℃, and the immersion time is 1-10 min.

8. The continuous surface modification method for PBO fabric according to claim 1, characterized in that, In step S5, drying is performed using hot air and / or infrared radiation at a temperature of 60-120℃ for 10-20 minutes.

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