Preparation method of marine environment adaptive modified fiber fishing net

Abstract

The invention discloses a preparation method of a marine environment adaptive modified fiber fishing net. The preparation method comprises the following steps: preparing a multifunctional spinning solution containing sodium alginate, chitosan, nano-hydroxyapatite and layered double hydroxides; performing micro-fluidic oriented spinning on the multifunctional spinning stock solution, and curing in a composite coagulating bath to form nascent fibers with an oriented structure; performing surface mineralization treatment on the nascent fiber to grow nano-hydroxyapatite and form a zinc oxide seed crystal layer; s3, synchronously growing a metal organic framework porous array and a metal conductive layer on the surface of the fiber treated in S3 through a hydrothermal reaction, and performing post-treatment; and S4, weaving the fibers treated in the step S4 into the fishing net. According to the preparation method disclosed by the invention, through a unique spinning solution formula and a bionic oriented spinning process, an organic-inorganic nano-hybrid oriented reinforced skeleton is constructed in situ in the fibers.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of marine fishing equipment materials, and particularly relates to a preparation method of a marine environment adaptive modified fiber fishing net. BACKGROUND

[0002] The performance of marine fishing equipment is directly related to the efficiency, safety and sustainability of fishing production. As one of the core equipment, the fishing net is soaked in the seawater environment with complex composition and numerous microorganisms for a long time, and faces the severe challenges of high-strength mechanical load, continuous salt corrosion and attachment of various marine organisms. Therefore, the industry has been committed to upgrading the fishing net material. The traditional fishing net mainly uses synthetic fibers such as polyethylene and nylon, and the performance is improved by surface coating of copper, tin and other antifouling agent coatings or organosilicon and other low surface energy substances. In recent years, research has further focused on imparting certain antibacterial, antifouling or reinforcing properties to the fishing net fiber through blending modification (such as adding inorganic nanoparticles), surface grafting of functional molecules or construction of layer self-assembly coating. These technical paths aim to improve the environmental tolerance of the fishing net from different angles, and constitute the main direction of the current development of fishing net material technology.

[0003] However, the above-mentioned prior art still has a series of inherent deficiencies in practical application, which is difficult to meet the urgent needs of modern marine fishing for high-performance and long-life fishing nets. First of all, most of the modification methods belong to "physical superposition" or "surface modification", which cannot realize the molecular-level fusion and structural integration of the reinforcing phase, functional phase and fiber matrix, resulting in limited mechanical property improvement and weak interface bonding. The functional layer is easy to fall off and fail under long-term water flow scouring and mechanical stress. Secondly, its corrosion resistance depends on the stability of the substrate itself or a simple barrier, lacking an active and long-acting corrosion inhibition mechanism, and cannot effectively respond to the harsh dynamic seawater environment. Thirdly, the problem of single function is prominent, and it is difficult to balance antifouling and reinforcement, not to mention integrating intelligent functions such as electrical conductivity. Finally, the traditional surface coating process has the risk of environmental pollution, and its protective effect decreases rapidly with the loss of the coating. Therefore, developing an integrated modified fiber fishing net preparation technology that can start from the source of structural design, realize mechanical strengthening, long-term corrosion resistance, multi-functional integration and environmental friendliness, has become a key technical bottleneck that needs to be broken through in the field. SUMMARY

[0004] In order to overcome the above-mentioned defects of the prior art, the present application provides a preparation method of a marine environment adaptive modified fiber fishing net, which solves the problem that the fishing net material in the prior art is not durable, has single function and is easy to fail due to non-integrated structure.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical scheme:

[0006] The preparation method of the marine environment adaptive modified fiber fishing net comprises the following steps:

[0007] S1: preparing a multifunctional spinning dope containing sodium alginate, chitosan, nano-hydroxyapatite and layered double hydroxide;

[0008] S2: microfluidic oriented spinning of the multifunctional spinning dope and solidification in a composite coagulation bath to form a nascent fiber with an oriented structure;

[0009] S3: surface mineralization treatment of the nascent fiber to grow nano-hydroxyapatite and form a zinc oxide seed layer;

[0010] S4: simultaneous growth of a metal-organic framework porous array and a metal conductive layer on the fiber surface treated by S3 through a hydrothermal reaction, and post-processing;

[0011] S5: weaving the fiber treated by S4 into a fishing net.

[0012] Preferably, step S1 specifically comprises: mixing sodium alginate and chitosan at a mass ratio of 1.5 to 2.5 to 1, adding a 2 to 3 weight percent concentration of acetic acid solution, stirring at a speed of 300 to 500 revolutions per minute for 60 to 90 minutes to dissolve; adding polyethylene glycol as a plasticizer and continuing to stir for 30 minutes to prepare a base solution; adding nano-hydroxyapatite and magnesium aluminum layered double hydroxide dispersion to the base solution, adding adipic dihydrazide and diisocyanate monomer after ultrasonic dispersion, and stirring at a constant temperature of 45 to 55 degrees Celsius to prepare the multifunctional spinning dope; wherein the total mass concentration of sodium alginate and chitosan is 3 to 5 weight percent.

[0013] Preferably, the molecular weight of the polyethylene glycol is 2000 to 4000 daltons, and the addition amount is 0.2 to 1.0 weight percent of the total mass of the base solution; the addition amount of the nano-hydroxyapatite is 2 to 4 weight percent of the total mass of the base solution, and the particle size is 50 to 100 nanometers; the addition amount of the magnesium aluminum layered double hydroxide dispersion is 10 to 14 weight percent of the total mass of the base solution in terms of solid content.

[0014] Preferably, in step S1: after preparing the multifunctional spinning dope, calcium chloride is added to adjust the viscosity to 500 to 800 millipascal seconds, and ammonium persulfate is added, activated at a constant temperature of 50 degrees Celsius, and vacuum degassed for standby.

[0015] Preferably, step S2 includes: injecting the deaerated spinning solution into a microfluidic spinning device, allowing it to pass through a liquid flow channel with a flow rate of 5 to 8 meters per second, inducing molecular chain orientation at a draw ratio of 3 to 5:1, and then extruding it through a spinneret with a diameter of 0.1 to 0.3 mm into a composite coagulation bath composed of 5% by weight calcium chloride, 2% by weight magnesium aluminum layered bimetallic hydroxide dispersion and 1% by weight dimethylamine borane, and curing it at 25 to 35 degrees Celsius for 5 to 10 minutes, simultaneously completing ionic crosslinking, coordination crosslinking and dynamic covalent crosslinking.

[0016] Preferably, step S3 specifically includes: washing the nascent fibers obtained in S2 to neutral pH, immersing them in a sodium dihydrogen phosphate solution with a pH of 7.0 to 7.5 and a concentration of 0.1 to 0.3 mol / L, and reacting at 35 to 40 degrees Celsius for 6 to 12 hours for mineralization; subsequently, immersing them in a zinc oxide precursor composed of a methanol solution of 0.05 mol / L zinc acetate and 0.1 mol / L potassium hydroxide, and repeating the immersion-drying operation 2 to 4 times at 100 degrees Celsius to form a zinc oxide nanocrystal seed layer.

[0017] Preferably, step S4 includes: immersing the fibers treated in S3 into a mixed reaction solution and hydrothermally reacting them at 60 to 80 degrees Celsius for 30 to 90 minutes; the mixed reaction solution contains 0.02 mol / L copper nitrate, 0.01 mol / L 2,3,6,7,10,11-hexahydroxybenzophenanthrene, and 0.05 mol / L silver nitrate; subsequently, annealing the fibers in a nitrogen atmosphere at 100 to 140 degrees Celsius for 20 to 40 minutes, and then hot-pressing them at 120 to 140 degrees Celsius and 5 to 8 MPa for 0.5 to 1.5 hours.

[0018] Preferably, the hydrothermal reaction is carried out at 70 to 75 degrees Celsius for 50 to 70 minutes.

[0019] Preferably, the composite coagulation bath also contains 0.3 to 0.8% by weight of sodium dodecyl sulfate.

[0020] Preferably, step S5 is: after twisting the fibers obtained in S4 with a twist of 300 to 500 twists per meter, weave them into a fishing net with a mesh count of 20 to 40 using a plain weave process.

[0021] The technical effects and advantages of the preparation method of the marine environment-adaptive modified fiber fishing net of the present invention are as follows:

[0022] 1. This invention utilizes a unique spinning solution formulation and a biomimetic orientation spinning process to construct an organic-inorganic nano-hybrid orientation reinforcement framework in situ within the fiber. This structure endows the fiber with both high strength and good toughness, resulting in mechanical properties significantly superior to traditional materials. Because the reinforcing phase forms a stable bond with the matrix during the molding process, particle aggregation and interface weakening problems are effectively avoided, thus ensuring uniform performance and long-term stability.

[0023] 2. The invention's unique surface mineralization treatment promotes the formation of a dense organic-inorganic interlocking protective layer on the fiber surface. This structure effectively blocks the penetration of corrosive media such as moisture and chloride ions in seawater, greatly delaying the material's hydrolysis, swelling, and strength degradation. Combined with a stable internal multi-linked network, the final product can maintain structural integrity and performance stability in harsh marine dynamic environments for a long time, significantly extending its service life.

[0024] 3. This invention integrates a porous array of metal-organic frameworks and a thin conductive metal layer onto the fiber surface, achieving intrinsic functionality through chemical bonding. This structure can continuously interfere with and disrupt the physiological activities of marine microorganisms, and inhibit the attachment of bacterial biofilms and large fouling organisms through physical and electrochemical effects. This method of functional attribution based on the material's own structure fundamentally overcomes the shortcomings of traditional surface coatings, such as easy wear and peeling, achieving a durable and highly efficient protective effect.

[0025] 4. This invention breaks through the limitations of traditional materials that only focus on a single performance, successfully integrating high strength, corrosion resistance, antibacterial and antifouling properties, and conductivity into one. The introduction of conductivity gives fishing nets the potential to respond to environmental energy (such as electrofouling) or serve as underwater sensing elements, realizing an intelligent upgrade from passive protection to active adaptation / monitoring, significantly enhancing the technological added value and application prospects of fishing nets.

[0026] 5. The entire preparation process of this invention, from spinning solution to finished fishing net, is tightly integrated, forming a continuous production path with excellent process controllability and potential for large-scale production. The final fishing net product strictly follows the weaving specifications of actual operations, ensuring its deployability, durability, and operational reliability in real marine environments, effectively transforming laboratory performance advantages into practical application value. Attached Figure Description

[0027] Figure 1 This is a flowchart of the preparation method of the marine environment-adaptive modified fiber fishing net proposed in this invention. Detailed Implementation

[0028] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0029] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include," "contain," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "includes..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0030] refer to Figure 1 This invention provides a method for preparing marine environment-adapted modified fiber fishing nets. Addressing the shortcomings of existing fishing net materials, such as insufficient mechanical properties, susceptibility to seawater corrosion and aging, easy adhesion of marine organisms, and limited functionality, this method offers an integrated modification approach from the structural design stage. The method first prepares a multifunctional spinning solution by compounding functional components such as sodium alginate, chitosan, nano-hydroxyapatite, and layered bimetallic hydroxides. Then, using microfluidic oriented spinning technology, fibers are shaped and simultaneously undergo multiple cross-linking in a specific composite coagulation bath, constructing a reinforcing framework with oriented internal molecular chains and nanoparticles. Subsequently, an organic-inorganic interlocking structure is grown through surface mineralization treatment, and further, a metal-organic framework porous array and a metal conductive thin-film functional layer are integratedly grown on the fiber surface through a low-temperature hydrothermal reaction. Finally, the modified fibers are twisted and woven to obtain the finished fishing net. This method, through multi-step synergy, constructs a multi-level stable structure in situ within and on the surface of the fibers, thereby endowing the fishing net with high strength, high toughness, excellent resistance to seawater corrosion, long-lasting and efficient antibacterial and antifouling properties, and additional conductivity in one step. It achieves a unified performance enhancement and multi-functional integration, significantly improving the fishing net's adaptability to marine environments and its service life.

[0031] Example 1

[0032] This embodiment provides a method for preparing a marine environment-adaptive modified fiber fishing net, used for the implementation of a complete process basic verification. Specific implementation details include:

[0033] Purpose of implementation:

[0034] This invention provides a basic implementation example, fully demonstrating the five core steps and verifying its feasibility.

[0035] Implementation steps:

[0036] S1: Preparation of Multifunctional Spinning Solution: 4.0 g of sodium alginate and 2.0 g of chitosan (mass ratio 2:1) were added to 194 g of 2% acetic acid solution and stirred at 400 rpm for 75 minutes. Then, 0.4 g of polyethylene glycol-4000 was added, and stirring continued for 30 minutes to obtain the base solution. 0.12 g of nano-hydroxyapatite (approximately 80 nm in particle size) and 12.0 g of a 10% solids content magnesium-aluminum layered bimetallic hydroxide dispersion were added to this solution and ultrasonically dispersed for 40 minutes. Then, 0.8 g of adipate dihydrazide and 0.5 g of hexamethylene diisocyanate were added, and the solution was stirred at 50°C for 2 hours. Finally, 0.24 g of calcium chloride and 0.04 g of ammonium persulfate were added, and after activation at 50°C for 15 minutes, the solution was degassed under a vacuum of -0.09 MPa for 30 minutes to obtain a spinning solution with a viscosity of approximately 650 mPa·s.

[0037] S2: Microfluidic Oriented Spinning and Curing: The deaerated stock solution is injected into a microfluidic spinning device, the auxiliary water flow rate is controlled at 6.5 m / s, the draw ratio is approximately 4:1, and it is extruded from a 0.2 mm diameter spinneret and cured in a 25°C composite coagulation bath for 8 minutes. The coagulation bath consists of a 5% calcium chloride, a 2% magnesium aluminum layered bimetallic hydroxide dispersion, and a 1% dimethylamine borane.

[0038] S3: Surface mineralization and seed layer construction: The cured nascent fibers were washed with water until neutral, then immersed in a 0.2 mol / L sodium dihydrogen phosphate solution with a pH of 7.2 and reacted at a constant temperature of 37°C for 12 hours. After washing, they were dried at 60°C for 30 minutes. Subsequently, the fibers were immersed in a zinc oxide precursor solution (a methanol solution of 0.05 mol / L zinc acetate and 0.1 mol / L KOH) for 10 seconds, then removed and dried at 100°C for 15 minutes. This process was repeated 3 times.

[0039] S4: Surface Functionalization and Post-treatment: The fiber was immersed in a mixed reaction solution (0.02 mol / L copper nitrate, 0.01 mol / L HHTP, 0.05 mol / L silver nitrate, solvent: water:ethanol = 1:1 v / v) and hydrothermally reacted at 70℃ for 60 minutes. After removal, it was dried with nitrogen gas, annealed at 120℃ for 30 minutes in a N2 atmosphere, and then hot-pressed at 130℃ and 6MPa for 1 hour.

[0040] S5: Fishing Net Weaving: The obtained fibers are twisted at a twist rate of 400 twists / meter and woven into a 30-mesh fishing net using a plain weave technique.

[0041] Implementation results:

[0042] Modified fibers and fishing nets were successfully prepared. The fiber structure is dense, and the surface functional layer is uniform. Performance tests show that its tensile strength is 4.2 cN / dtex, and the strength retention rate after 30 days of simulated seawater immersion is 88.5%. The 24-hour antibacterial rate against Escherichia coli and Staphylococcus aureus both exceed 99.5%. In the antifouling test, the inhibition rate against barnacle larvae attachment reaches 94.2%, and the surface resistivity is 1.5 × 10⁻⁶. 3 Ω / sq.

[0043] Example 2

[0044] This embodiment provides a method for preparing a marine environment-adapted modified fiber fishing net, used for the implementation of biopolymer ratio optimization verification. Specific implementation details include:

[0045] Purpose of implementation:

[0046] The effects of changes in raw material ratios (especially the mass ratio of sodium alginate to chitosan) on the properties of spinning solution and final fibers are shown.

[0047] Implementation steps:

[0048] The steps in this embodiment are basically the same as those in Embodiment 1, except that in S1:

[0049] The amount of sodium alginate was adjusted to 4.4 g, and chitosan to 2.0 g (mass ratio 2.2:1, within the range of 1.5-2.5:1 as defined in claim 2). The amount of polyethylene glycol-4000 was 0.6 g. The amount of nano-hydroxyapatite was 0.24 g. The solid addition amount of the magnesium-aluminum layered bimetallic hydroxide dispersion was adjusted to 1.44 g. The final spinning solution viscosity was approximately 720 mPa·s.

[0050] Implementation results:

[0051] The resulting fiber exhibits balanced mechanical properties, with a breaking strength of 4.5 cN / dtex and a breaking elongation of 14.8%. This embodiment demonstrates that by adjusting the composition within the preferred proportions defined in the claims, fibers possessing both good strength and toughness can be obtained.

[0052] Example 3

[0053] This embodiment provides a method for preparing a marine environment-adapted modified fiber fishing net, used for the optimization and verification of spinning and mineralization process parameters. Specific implementation details include:

[0054] Purpose of implementation:

[0055] The spinning and curing process parameters, as well as the optimization effect of the mineralization process, are presented.

[0056] Implementation steps:

[0057] The steps in this embodiment are basically the same as those in Embodiment 1, with the following differences:

[0058] S2: Adjust the coagulation bath temperature to 30℃ and shorten the curing time to 6 minutes.

[0059] S3: The concentration of the mineralizing solution is adjusted to 0.1 mol / L, and the reaction time is extended to 12 hours (within the range of 6-12 hours as defined in claim 6).

[0060] Implementation results:

[0061] The optimized process facilitated the formation of a denser, more uniform mineralized layer. The resulting fibers exhibited an increased elongation at break of 16.1% and a strength retention rate of 91.0% after seawater immersion, demonstrating superior toughness and long-term environmental durability.

[0062] Example 4

[0063] This embodiment provides a method for preparing a marine environment-adapted modified fiber fishing net, used for the implementation of surfactant addition and functionalization condition optimization verification. Specific implementation details include:

[0064] Purpose of implementation:

[0065] The preferred surface functionalization scheme is demonstrated, and the effect of adding the surfactant sodium dodecyl sulfate in the coagulation bath is verified.

[0066] Implementation steps:

[0067] This embodiment makes two key optimizations based on Embodiment 1:

[0068] S2: The composition of the composite coagulation bath is changed to: 5% calcium chloride, 2% magnesium aluminum layered bimetallic hydroxide dispersion, 1% dimethylamine borane and 0.5% sodium dodecyl sulfate (the amount added is relative to the total mass of the coagulation bath).

[0069] S4: The hydrothermal reaction temperature is adjusted to 75°C and the reaction time is adjusted to 55 minutes (the parameters are within the range of 70-75°C and 50-70 minutes as defined in claim 8).

[0070] Implementation results:

[0071] Adding SDS to the coagulation bath significantly improved the wettability of the spinning solution and the uniformity of inorganic particle dispersion, resulting in more regular cross-sections and fewer defects in the nascent fibers. Combined with optimized hydrothermal conditions, the resulting fibers exhibited outstanding overall performance: breaking strength increased to 4.6 cN / dtex, and surface resistivity decreased to 0.8 × 10⁻⁶. 3With an Ω / sq content, the antibacterial rate reaches over 99.9%, and the functional layer is more firmly bonded to the fiber matrix.

[0072] Example 5

[0073] This embodiment provides a method for preparing a marine environment-adaptive modified fiber fishing net, used for the implementation of performance verification of a comprehensive optimized scheme. Specific implementation details include:

[0074] Purpose of implementation:

[0075] An implementation example incorporating multiple preferred parameters is provided to demonstrate the optimal performance achievable by the method of the present invention.

[0076] Implementation steps:

[0077] S1: Preparation of spinning solution: Sodium alginate and chitosan were mixed at a mass ratio of 1.8:1, with a total concentration of 4.0%. Polyethylene glycol was added at 0.5%, nano-hydroxyapatite at 3%, and magnesium-aluminum layered bimetallic hydroxide solids at 11%. The molar ratio of adipic acid dihydrazide to chitosan amino groups was 1:1.5. The final solution viscosity was approximately 700 mPa·s.

[0078] S2: Spinning and Curing: Auxiliary water flow rate is 7 m / s, draw ratio is 4.5:1, and spinneret diameter is 0.15 mm. The coagulation bath temperature is 28℃, and its composition is: 5% CaCl2, 2% MgAl-LDH dispersion, 1% dimethylamine borane, and 0.5% sodium dodecyl sulfate (addition amount relative to the total mass of the coagulation bath), with curing time of 7 minutes.

[0079] S3: Surface mineralization and seed layer construction: A 0.25 mol / L NaH2PO4 solution with pH=7.4 was used, and the reaction was carried out at 40°C for 10 hours. The zinc oxide seed layer was constructed in the same manner as in Example 1.

[0080] S4: Surface functionalization and post-treatment: The hydrothermal reaction was carried out at 72°C for 65 minutes (parameters within the range defined in claim 8). The post-treatment was annealing in N2 at 130°C for 25 minutes, followed by hot pressing at 135°C and 6.5 MPa for 45 minutes.

[0081] S5: Fishing net weaving: with a twist of 450 twists / meter, weave into a 25-mesh fishing net.

[0082] Implementation results:

[0083] Through system optimization, the fiber produced in this embodiment exhibits the best overall performance: a breaking strength as high as 5.1 cN / dtex, a 97.5% inhibition rate against barnacle larvae attachment in the antifouling test, a strength retention rate of 90.2% after seawater immersion, an antibacterial rate exceeding 99.9%, and a surface resistivity of 1.0 × 10⁻⁶. 3Ω / sq.

[0084] Comparative Example 1

[0085] This comparative example provides an implementation for comparison with conventional impregnation processes, specifically including:

[0086] Purpose of implementation:

[0087] The simple processing techniques used to simulate traditional fishing net materials are compared with the integrated modification method of this invention to highlight the structural advantages and performance improvements of this invention.

[0088] Implementation steps:

[0089] S1: Dissolve 6 grams of sodium alginate in deionized water to prepare a spinning solution of approximately 3%.

[0090] S2: Conventional wet spinning is used, and the spinning solution is injected into a 5% calcium chloride coagulation bath to form ordinary calcium alginate fiber.

[0091] S3: After washing and drying the fibers, immerse them in commercially available silicone antifouling coating and allow them to air dry and cure at room temperature.

[0092] S4: Twist the treated fibers at a twist rate of 400 twists / meter and weave them into a 30-mesh fishing net.

[0093] Implementation results:

[0094] The resulting fibers are merely calcium alginate substrates modified with a simple physical coating. Their tensile strength is only 1.8 cN / dtex, and after immersion in simulated seawater for 30 days, the strength drops significantly (62.3% retention rate). Their antibacterial and antifouling properties are limited and not durable (antibacterial rate approximately 75%, antifouling inhibition rate 30.5%), and the surface is insulating. Compared to Examples 1-5, all performance characteristics show significant differences, fully demonstrating the performance leap brought about by the integrated structural design of this invention.

[0095] Performance Test Summary:

[0096] The core properties of the fibers prepared in each embodiment and comparative example are compared through a series of tests as follows:

[0097] In terms of overall performance, Example 5 is the most outstanding. Its fiber breaking strength reaches 5.1 cN / dtex, exhibiting excellent antifouling properties (97.5% inhibition rate of barnacle larvae attachment), while maintaining high levels of seawater corrosion resistance (90.2% strength retention), antibacterial properties (>99.9%), and good electrical conductivity (surface resistivity 1.0 × 10⁻⁶). 3 (Ω / sq), which reflects the optimal effect of the method of the present invention under system optimization.

[0098] Specifically:

[0099] Example 1 serves as the basic scheme, exhibiting balanced performance across various aspects. Its fracture strength is 4.2 cN / dtex, and its corrosion resistance (strength retention rate of 88.5%), antibacterial properties (>99.5%), and stain resistance (inhibition rate of 94.2%) far exceed those of the comparative example.

[0100] In Example 2, after adjusting the biopolymer composition within the preferred ratio, the fiber strength was increased to 4.5 cN / dtex while maintaining good toughness.

[0101] Example 3 significantly improved the long-term durability of the fiber by optimizing the coagulation and mineralization process. Its strength retention rate after seawater immersion was the highest among all examples, reaching 91.0%.

[0102] Example 4 achieved the best results in terms of electrical conductivity (surface resistivity 0.8 × 10⁻⁶) by introducing the surfactant sodium dodecyl sulfate and optimizing the hydrothermal conditions. 3 (Ω / sq), while the antibacterial properties reach the limit.

[0103] Compared to Examples 1-5 and Comparative Example 1, Examples 1-5 systematically demonstrate the "Preparation Method of Marine Environment-Adapted Modified Fiber Fishing Net" of the present invention, and form a stark contrast with the traditional simple processing technology represented by Comparative Example 1. Through direct comparison of a series of performance test data, the following conclusions can be clearly drawn:

[0104] Comparative Example 1 employs a traditional two-step process: "substrate fiber preparation + simple surface impregnation coating." This process is essentially a physical functional superposition, producing calcium alginate fibers with only a single layer of silicone coating. The internal structure is loose, and the interfacial bonding is weak. Therefore, its overall performance is poor: the fiber's intrinsic strength is low (1.8 cN / dtex), making it susceptible to corrosion and degradation in simulated marine environments (strength retention rate only 62.3%). The coating provides limited and short-lived antibacterial and antifouling capabilities (antibacterial rate ~75%, antifouling inhibition rate 30.5%), and it lacks any functional response (insulation).

[0105] In contrast, Examples 1-5 of this invention utilize an integrated continuous process of "molecular design - biomimetic spinning - in-situ mineralization - interface functionalization" to construct a multi-level synergistic structure from the inside out. This structural innovation brings about a qualitative change:

[0106] Fundamental improvement in mechanical properties: The fiber breaking strength (4.2-5.1 cN / dtex) of all embodiments is more than 2.3 times that of the comparative example (1.8 cN / dtex). This is due to the internal ordered structure formed by microfluidic oriented spinning, the reinforcing effect of nanoparticles, and the multiple cross-linked network.

[0107] Revolutionary advancements in durability: The seawater corrosion resistance of the embodiment (strength retention rate 85.2%-91.0%) is far superior to that of the comparative example (62.3%). This is attributed to the dense mineralized layer on the surface and the organic-inorganic interlocking structure, which effectively prevents the penetration and damage of water molecules and corrosive ions.

[0108] Long-lasting and integrated functionality: The antibacterial rate (>99.3%) and stain-resistant inhibition rate (>92.8%) of the embodiments are close to or reach the limit level, and its function originates from the fiber body and the firmly bonded surface functional layers (MOF array and Ag layer), rather than easily detachable physical coatings, thus possessing long-lasting effectiveness. Simultaneously, the embodiments also endow the fibers with conductive properties (resistivity 10⁻⁶). 3 (on the order of Ω / sq), this is a new feature that is completely absent in scales.

[0109] Example 1, serving as the foundational verification, has comprehensively surpassed the comparative example. Building upon this, subsequent examples, by optimizing the key process parameters protected by the claims, demonstrate further potential for performance improvement:

[0110] Example 2 optimized the material's toughness balance while maintaining high strength by adjusting the ratio of biopolymers.

[0111] Example 3 improved corrosion resistance to the best (91.0%) by optimizing solidification and mineralization conditions, highlighting the critical impact of process details on long-term durability.

[0112] Examples 4 and 5 optimized the coagulation process by introducing a surfactant (sodium dodecyl sulfate) and combined it with a precisely controlled hydrothermal reaction, thereby improving electrical conductivity to an optimal level (0.8 × 10⁻⁶) while maintaining high strength and high corrosion resistance. 3 (Ω / sq), and pushes antibacterial and antifouling properties to the extreme. This proves that the present invention is not a fixed formula, but a technical platform that can be optimized through parameter tuning to obtain high-performance products with different focuses.

[0113] In summary, the traditional process in Comparative Example 1 can only produce a fishing net material with mediocre performance, short lifespan, limited functionality, and susceptibility to failure. In contrast, Examples 1-5 of this invention successfully prepared a "marine environment-adaptive" fiber with high strength, excellent corrosion resistance, highly efficient and durable antibacterial and antifouling properties, and additional conductivity. The significant difference in performance between the two cannot be achieved through simple process improvements or material substitution; the fundamental reason lies in the innovative integrated multi-level structural construction concept of this invention. Experimental data from the specific embodiments fully demonstrate that this invention solves the core technical problems of rapid strength decay, severe biofouling, limited functionality, and susceptibility to failure of traditional fishing net materials in harsh marine environments, demonstrating significant progress and outstanding substantive characteristics.

[0114] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of protection of the claims.

[0115] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a marine environment-adapted modified fiber fishing net, characterized in that, Includes the following steps: S1: Preparation of a multifunctional spinning solution containing sodium alginate, chitosan, nano-hydroxyapatite and layered bimetallic hydroxide; S2: The multifunctional spinning solution is subjected to microfluidic orientation spinning and solidified in a composite coagulation bath to form nascent fibers with an orientation structure. S3: The nascent fibers are subjected to surface mineralization treatment to grow nano-hydroxyapatite and form a zinc oxide seed layer; S4: On the fiber surface treated by S3, a porous array of metal-organic framework and a metal conductive layer are grown simultaneously by hydrothermal reaction, and then post-processed. S5: Weave the fibers treated with S4 into fishing nets.

2. The method for preparing the marine environment-adapted modified fiber fishing net as described in claim 1, characterized in that, Step S1 specifically includes: mixing sodium alginate and chitosan at a mass ratio of 1.5 to 2.5:1, adding them to an acetic acid solution with a concentration of 2 to 3% by weight, and stirring at a rate of 300 to 500 rpm for 60 to 90 minutes until dissolved; adding polyethylene glycol as a plasticizer and continuing to stir for 30 minutes to obtain a base solution; adding nano-hydroxyapatite and magnesium aluminum layered bimetallic hydroxide dispersion to the base solution, ultrasonically dispersing it, adding adipic acid dihydrazide and diisocyanate monomer, and stirring at a constant temperature of 45 to 55 degrees Celsius to obtain the multifunctional spinning solution; wherein the total mass concentration of sodium alginate and chitosan is 3 to 5% by weight.

3. The method for preparing the marine environment-adapted modified fiber fishing net as described in claim 2, characterized in that, The polyethylene glycol has a molecular weight of 2000 to 4000 Daltons and is added at a weight percentage of 0.2 to 1.0% of the total mass of the base solution; the nano-hydroxyapatite is added at a weight percentage of 2 to 4% of the total mass of the base solution and has a particle size of 50 to 100 nanometers; the magnesium-aluminum layered bimetallic hydroxide dispersion is added at a weight percentage of 10 to 14% of the total mass of the base solution on a solids basis.

4. The method for preparing the marine environment-adapted modified fiber fishing net as described in claim 2, characterized in that, In step S1: After obtaining the multifunctional spinning solution, calcium chloride is added to adjust its viscosity to 500 to 800 mPa·s, and ammonium persulfate is added. After constant temperature activation at 50 degrees Celsius and vacuum degassing, it is ready for use.

5. The method for preparing the marine environment-adapted modified fiber fishing net as described in claim 1, characterized in that, Step S2 includes: injecting the degassed spinning solution into a microfluidic spinning device, allowing it to pass through a liquid flow channel with a flow rate of 5 to 8 meters per second, inducing molecular chain orientation at a draw ratio of 3 to 5:1, and then extruding it through a spinneret with a diameter of 0.1 to 0.3 mm, entering a composite coagulation bath composed of 5% by weight calcium chloride, 2% by weight magnesium aluminum layered bimetallic hydroxide dispersion and 1% by weight dimethylamine borane, and curing it at 25 to 35 degrees Celsius for 5 to 10 minutes, simultaneously completing ionic crosslinking, coordination crosslinking and dynamic covalent crosslinking.

6. The method for preparing the marine environment-adapted modified fiber fishing net as described in claim 1, characterized in that, Step S3 specifically includes: washing the nascent fibers obtained in S2 to neutral pH, then immersing them in a sodium dihydrogen phosphate solution with a pH of 7.0 to 7.5 and a concentration of 0.1 to 0.3 mol / L, and reacting at 35 to 40 degrees Celsius for 6 to 12 hours for mineralization; subsequently, immersing them in a zinc oxide precursor composed of a methanol solution of 0.05 mol / L zinc acetate and 0.1 mol / L potassium hydroxide, and repeating the soaking-drying operation 2 to 4 times at 100 degrees Celsius to form a zinc oxide nanocrystal seed layer.

7. The method for preparing the marine environment-adapted modified fiber fishing net as described in claim 1 or 6, characterized in that, Step S4 includes: immersing the fibers treated in S3 into a mixed reaction solution and hydrothermally reacting them at 60 to 80 degrees Celsius for 30 to 90 minutes; the mixed reaction solution contains 0.02 mol / L copper nitrate, 0.01 mol / L 2,3,6,7,10,11-hexahydroxybenzophenanthrene, and 0.05 mol / L silver nitrate; subsequently, annealing the fibers in a nitrogen atmosphere at 100 to 140 degrees Celsius for 20 to 40 minutes, and then hot-pressing them at 120 to 140 degrees Celsius and 5 to 8 MPa for 0.5 to 1.5 hours.

8. The method for preparing the marine environment-adapted modified fiber fishing net as described in claim 7, characterized in that, The hydrothermal reaction is carried out at 70 to 75 degrees Celsius for 50 to 70 minutes.

9. The method for preparing the marine environment-adapted modified fiber fishing net as described in claim 1, characterized in that, The composite coagulation bath also contains 0.3 to 0.8% by weight of sodium dodecyl sulfate.

10. The method for preparing the marine environment-adapted modified fiber fishing net as described in claim 1, characterized in that, Step S5 is as follows: after twisting the fibers obtained in S4 at a twist rate of 300 to 500 twists per meter, weave them into a fishing net with a mesh count of 20 to 40 using a plain weave process.

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