Anti-fouling and anti-biological-adhesion PE / PTFE (Polyethylene / Polytetrafluoroethylene) composite fiber and preparation method thereof

Abstract

The invention relates to the field of fiber materials, and particularly discloses an anti-fouling and anti-biological adhesion PE / PTFE composite fiber and a preparation method thereof. The PE / PTFE composite fiber is of a layered structure, the inner layer is modified polyethylene fiber, and the outer layer is a PTFE coating layer. Due to the action of the coating layer PTFE, the surface of the fiber has the characteristic of low surface energy, the water contact angle of the surface of the fiber is larger than or equal to 150 degrees, adhesion of organisms such as various algae in a water body can be effectively avoided, the fiber has high strength, organism adhesion prevention, high antifouling property and self-cleaning property, and the organisms attached to the water body are difficult to adhere to stain or have very low adhesive force. And the modified polyethylene material fluorine-containing polyethylene is introduced through a modification process, so that the interface bonding force between the PTFE skin layer and the PE material is effectively improved, the overall strength of the fiber is improved, the wear resistance can be effectively improved, and the fiber has excellent antifouling and biological adhesion prevention performance.

Description

Technical Field

[0001] The present application relates to the field of materials, and more specifically, to an anti-fouling and anti-biological attachment PE / PTFE composite fiber and a preparation method thereof. Background Art

[0002] As human demand for seafood continues to grow, overfishing and human pollution of marine life are becoming increasingly serious. Against this background, the global cage aquaculture industry has developed rapidly, but it has also brought about the problem of marine life attaching to cages and nets. These attached organisms will block the mesh, affect seawater convection, reduce dissolved oxygen and food supply, cause stunted development or even death of farmed seafood, and seriously affect the production and quality of aquaculture. Traditional manual or mechanical removal methods are labor-intensive, inefficient, and easily damage the cages and affect the aquaculture cycle.

[0003] Although the antifouling coatings currently on the market can slow down the attachment of marine organisms, they often contain metal ions that are harmful to the environment, and the antifouling effect is short-lived, making them not environmentally friendly or sustainable solutions. In addition, offshore facilities such as wind turbine buoys, submarine cables, mooring systems, and aquaculture cages are also affected by the attachment of marine organisms, which can change the physical and chemical properties of the materials, shorten their service life, and may cause ecological disasters, such as the Enteromorpha green tide in the Yellow Sea. There are several major problems with traditional cage aquaculture: first, the cages are easily attached by marine organisms such as barnacles and algae, causing the cages to be fouled and forming a fence effect; second, the poor flow of seawater and increased resistance may cause the cages to be washed away; third, artificially placed fish feed and fish excrement are difficult to be carried away by flowing seawater, which will cause water pollution in the cages, and then cause fish diseases and deaths.

[0004] Therefore, the development of new, environmentally friendly and durable antifouling materials and technologies to deal with the problem of marine biofouling is a key issue that needs to be urgently addressed in the field of marine engineering. Such materials need to have good anti-adhesion properties and mechanics, while being safe and sustainable for the marine environment to protect the marine ecology and extend the service life of offshore facilities. Summary of the invention

[0005] In order to solve the above technical problems, the present application provides an anti-fouling and anti-biological attachment PE / PTFE composite fiber and a preparation method thereof.

[0006] This application adopts the following technical solutions: In a first aspect, the present application provides a PE / PTFE composite fiber for preventing fouling and biofouling, wherein the PE / PTFE composite fiber is a layered structure, wherein the inner layer is a modified polyethylene fiber, and the outer layer is a PTFE coating layer, wherein the mass percentage of the PTFE coating layer is 3-35wt%; The tensile strength of the PE / PTFE composite fiber is above 5.8 cN / dtex, the amount of biological attachment on the surface of the fiber after being immersed in seawater for half a year is below 0.0012 g / m, and the amount of biological attachment on the surface of the fiber after being rubbed 5000 times and immersed in seawater for half a year is below 0.0022 g / m.

[0007] Furthermore, the modified polyethylene fiber is obtained by composite melt spinning of polyethylene resin slices and fluorine-containing polyethylene resin slices, wherein the polyethylene resin serves as the core layer and the fluorine-containing polyethylene resin serves as the skin layer.

[0008] Furthermore, in the modified polyethylene fiber, the core layer accounts for 5-90 parts by weight, and the skin layer accounts for 25-95 parts by weight.

[0009] In a second aspect, the present application provides a method for preparing the above-mentioned anti-fouling and anti-biological attachment PE / PTFE composite fiber, which comprises: The PTFE resin is blended with isoparaffin solvent oil, softened, and coated on the surface of the modified polyethylene fiber. After cooling, the PTFE coating layer is formed by deoiling to obtain the PE / PTFE composite fiber.

[0010] Furthermore, the softening process includes: the PTFE resin is blended and melt-softened with the isoparaffin solvent oil at 100-300° C. through a screw extruder; Preferably, the deoiling temperature during the formation of the PTFE coating layer is 80-250°C.

[0011] Furthermore, the preparation method of the modified polyethylene fiber comprises: Dispersing fluorinated acrylate, benzophenone compounds, and alkyl esters containing thioperoxydicarbonate in an organic solvent to obtain a modified solution; Adding polyethylene resin chips to the modified liquid, stirring under an inert atmosphere to obtain a solid-liquid mixture, irradiating the solid-liquid mixture under ultraviolet light of 245-260 nm, continuously stirring and introducing an inert gas, and then filtering and drying to obtain fluorinated polyethylene resin chips; The polyethylene resin slices and the fluorine-containing polyethylene resin slices are composite melt-spun, and then heat-drawn to prepare modified polyethylene fibers with a skin layer of fluorine-containing polyethylene resin and a core layer of unmodified polyethylene resin.

[0012] Furthermore, the above-mentioned fluorine-containing acrylate includes one or a combination of 2-(perfluorobutyl)ethyl methacrylate, 2-(perfluorooctyl)ethyl methacrylate, 2-(perfluorohexyl)ethyl methacrylate, 2-(perfluorodecyl)ethyl methacrylate, 2-perfluorooctylethyl acrylate, 3-(perfluoro-5-methylhexyl)-2-hydroxypropyl methacrylate, 1,1,1,3,3,3-hexafluoroisopropyl acrylate, and 2-(perfluorododecyl)ethyl acrylate.

[0013] Furthermore, in the above-mentioned modified liquid, the molar ratio of the fluorine-containing acrylate, the benzophenone compound, and the alkyl ester containing thioperoxydicarbonate is (80-350):1:1.

[0014] Preferably, the benzophenone compound is (4-methoxyphenyl)(4-(trifluoromethyl)phenyl)methanone, and the alkyl ester containing thioperoxydicarbonate is thioperoxydicarbonate ([(HS)C(S)]2S2) C,C'-dioctadecyl ester.

[0015] Furthermore, in the process of preparing the fluorinated polyethylene resin chips, the temperature of the solid-liquid mixture is controlled to be 10-60° C., and the ultraviolet lamp irradiation time is 3-48 hours.

[0016] Furthermore, in the above composite melt spinning process, the spinning temperature is 100-240° C., the hot drawing temperature is 80-130° C., and the drawing multiple is 3-15 times.

[0017] In summary, this application has the following beneficial effects: 1. The PE / PTFE composite fiber provided in the present application has an outer layer of a PTFE coating layer, i.e., a polytetrafluoroethylene coating layer. Since fluorine-containing polymers generally have a lower surface energy and are not easy to adhere to other substances, the present application introduces fluorine-containing materials to prepare anti-fouling and anti-attachment fibers. Currently, fluorine-containing polymers mainly include polytetrafluoroethylene (PTFE), tetrafluoroethylene-perfluoroalkoxy vinyl ether copolymer (PFA) and polyvinylidene fluoride (PVDF). Compared with other materials, these three materials have better anti-fouling and anti-biological attachment effects; and compared with the three, since PTFE and PFA have high fluorine content and PVDF has a relatively low fluorine content, PTFE and PFA have better anti-fouling and anti-biological attachment effects, so they can be selected as materials for preparing anti-fouling and anti-biological attachment materials.

[0018] 2. However, due to the difficulty in processing PTFE and PFA, their high prices, and their own mechanical properties compared to conventional polymer fibers, such as polyethylene (PE), polypropylene (PP), polyester (PET), polyamide (PA), etc., the mechanical properties of PTFE and PFA fibers are much lower than these conventional polymer fiber materials. This disadvantage limits the application of fluoropolymers such as PTFE and PFA in the field of anti-fouling and anti-biological attachment. The applicant prepares fibers by compounding fluoropolymers such as PTFE with traditional polymers such as PE, PP, PET, etc., which theoretically can combine the advantages of both types of materials, thereby ensuring the mechanical properties of the fiber while having anti-fouling and anti-biological attachment properties.

[0019] 3. Due to the low surface energy of fluorinated polymer materials such as PFA and PTFE, when compounded with fluorine-free polymers, the two different types of polymers are incompatible, and the interface interaction between the two is low, and a good bonding interface cannot be formed, which will greatly affect the performance of the material and cause negative situations such as shedding and delamination. Therefore, when the PE / PTFE composite fiber provided by the present application is composited with the fluorinated polymer and the fluorine-free polymer, the interface problem between the two types of materials is focused on and solved. By introducing the modified polyethylene material of fluorinated polyethylene, the interface bonding force between the PTFE coating layer and the PE material is effectively improved, and the overall strength of the fiber is increased, and the wear resistance can also be effectively improved, thereby extending the service life of the fiber and its products and the effective time of preventing biological attachment.

[0020] 4. The tensile strength of the PE / PTFE fiber provided in the present application is greater than or equal to 5.8 cN / dtex. Due to the effect of the coating layer PTFE, the fiber surface exhibits the characteristics of low surface energy, and the water contact angle of the fiber surface is ≥150 degrees, which can effectively avoid the adhesion of various algae and other organisms in the water body. It has high strength, anti-biological attachment, high anti-fouling and self-cleaning properties, and it is difficult for organisms attached to the water body to attach and be contaminated or the adhesion is very low. The amount of biological attachment on the surface of the fiber after being immersed in seawater for half a year is less than or equal to 0.0012 g / m, and the amount of biological attachment on the surface of the fiber after being rubbed 5000 times and immersed in seawater for half a year is less than or equal to 0.0022 g / m, which has excellent anti-biological attachment effect. This suggests that the wires, ropes, cables, nets, etc. made of the composite fiber provided by the present invention also have the excellent performance corresponding to the composite fiber, and have excellent anti-biological attachment function when used in water bodies. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the cross-sectional structure of the PE / PTFE composite fiber provided in this application. DETAILED DESCRIPTION

[0022] The embodiments of the present invention will be described in detail below in conjunction with examples. However, those skilled in the art will understand that the following examples are only used to illustrate the present invention and should not be construed as limiting the scope of the present invention. The specific conditions not specified in the examples are carried out according to conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used without indicating the manufacturer are all conventional products that can be purchased commercially.

[0023] The specific embodiments of the present invention are described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0024] Example 1 This embodiment provides a PE / PTFE composite fiber that is anti-fouling and anti-biological adhesion. It has a layered structure, an inner layer of modified polyethylene fiber, an outer layer of PTFE coating layer, and a cross-sectional structure as shown in FIG. Figure 1 shown.

[0025] The preparation method of the PE / PTFE composite fiber comprises the following steps: Step 1: Using dioxane as a solvent, a benzophenone compound as shown in Formula 1, thioperoxydicarbonic acid as shown in Formula 2, and 2-(perfluorobutyl)ethyl methacrylate are mixed at a ratio of 1:1:105 to obtain a modified solution. A polyethylene resin chip with a weight average molecular weight of 100,000 is added to the modified solution, and the mass ratio of the polyethylene resin chip to 2-(perfluorobutyl)ethyl methacrylate is 1:20. High-purity argon gas is introduced at 150 ml / min, and stirred for 60 minutes to obtain a solid-liquid mixture.

[0026] Step 2: The solid-liquid mixture obtained in step 1 was irradiated with ultraviolet light of wavelength 253 nm for 12 hours, and during the irradiation process, the mixture was continuously stirred and argon gas was introduced at an amount of 200 ml / min, and the temperature of the solid-liquid mixture was controlled at 20° C. The irradiated solid-liquid mixture was filtered and dried at 60° C. for 3 hours to obtain fluorinated polyethylene resin slices.

[0027] Step 3: The fluorinated polyethylene resin slices obtained in step 2 and the polyethylene resin slices (weight-average molecular weight of 100,000) are used as raw materials, and composite melt spinning is performed in a composite spinning machine; the composite spinning machine includes two single-screw extruders, and the spinning temperature of the composite spinning machine is 230°C. The fluorinated polyethylene resin and the unmodified polyethylene resin are respectively added to different single-screw extruders to melt to form a melt, which is metered and transported to the composite spinning component by the metering pumps equipped with each, and extruded through the composite spinneret to obtain a continuous melt with the fluorinated polyethylene as the skin layer and the unmodified polyethylene resin as the core layer, in which the mass of the fluorinated polyethylene accounts for 8 parts and the mass of the unmodified polyethylene resin accounts for 92 parts; after air cooling and solidification, the modified polyethylene fiber with the skin layer of the fluorinated polyethylene resin and the core layer of the unmodified polyethylene resin is prepared by drawing 8 times at 90 degrees Celsius, in which the mass of the skin layer accounts for 8 parts and the mass of the core layer accounts for 92 parts.

[0028] Step 4: melt and soften the PTFE resin and isoparaffin solvent oil at 130 degrees Celsius using a twin-screw extruder, coat the surface of the modified polyethylene fiber obtained in step 3 through a melt coating process, and then deoil at 150 degrees Celsius to form a PTFE cortex. After cooling, PE / PTFE composite fibers are obtained, and the mass of the cortex PTFE accounts for 15% of the total fiber mass.

[0029] Example 2 This embodiment provides a PE / PTFE composite fiber that is anti-fouling and anti-biological attachment, and the preparation method thereof includes: Step 1: Using dioxane as a solvent, a benzophenone compound as shown in Formula 1, thioperoxydicarbonic acid as shown in Formula 2, and 2-(perfluorooctyl)ethyl methacrylate are mixed at a ratio of 1:1:110 to obtain a modified solution. A polyethylene resin chip with a weight average molecular weight of 80,000 is added to the modified solution, and the mass ratio of the polyethylene resin chip to 2-(perfluorooctyl)ethyl methacrylate is 1:30. High-purity argon gas is introduced at 150 ml / min, and stirred for 60 minutes to obtain a solid-liquid mixture.

[0030] Step 2: The solid-liquid mixture obtained in step 1 was irradiated with ultraviolet light of wavelength 253 nm for 14 hours. During the irradiation process, the mixture was continuously stirred and argon gas was introduced at an amount of 300 ml / min. The temperature of the solid-liquid mixture was controlled at 25 degrees Celsius. The irradiated solid-liquid mixture was filtered and dried at 60 degrees Celsius for 4 hours to obtain fluorinated polyethylene resin slices.

[0031] Step 3: The fluorinated polyethylene resin slices obtained in step 2 and the polyethylene resin slices (weight-average molecular weight of 80,000) are used as raw materials and composite melt spinning is performed in a composite spinning machine; the composite spinning machine comprises two single-screw extruders, the spinning temperature of the composite spinning machine is 230 degrees Celsius, the fluorinated polyethylene resin and the unmodified polyethylene resin are respectively added to different single-screw extruders to melt to form a melt, which is metered and transported to the composite spinning assembly by respectively equipped metering pumps, and extruded through a composite spinneret to obtain a continuous melt with fluorinated polyethylene as the skin layer and unmodified polyethylene resin as the core layer, in which the mass of fluorinated polyethylene accounts for 9.5 parts and the mass of unmodified polyethylene resin accounts for 90.5 parts; after air cooling and solidification, the modified polyethylene fiber with the skin layer of fluorinated polyethylene resin and the core layer of unmodified polyethylene resin is prepared by drawing 9 times at 110 degrees Celsius, in which the mass of the skin layer accounts for 10 parts and the mass of the core layer accounts for 90 parts.

[0032] Step 4: melt and soften the PTFE resin and isoparaffin solvent oil at 150 degrees Celsius using a twin-screw extruder, coat the surface of the modified polyethylene fiber obtained in step 3 through a melt coating process, and then deoil at 160 degrees Celsius to form a PTFE cortex. After cooling, PE / PTFE composite fibers are obtained, and the mass of the cortex PTFE accounts for 17% of the total fiber mass.

[0033] Example 3 This embodiment provides a PE / PTFE composite fiber that is anti-fouling and anti-biological attachment, and the preparation method thereof includes: Step 1: Using dioxane as a solvent, a benzophenone compound as shown in Formula 1, thioperoxydicarbonic acid as shown in Formula 2, and 2-(perfluorohexyl)ethyl methacrylate are mixed at a ratio of 1:1:120 to obtain a modified solution. A polyethylene resin chip with a weight average molecular weight of 100,000 is added to the modified solution, and the mass ratio of the polyethylene resin chip to 2-(perfluorohexyl)ethyl methacrylate is 1:50. High-purity argon gas is introduced at 150 ml / min, and stirred for 60 minutes to obtain a solid-liquid mixture.

[0034] Step 2: The solid-liquid mixture obtained in step 1 was irradiated with ultraviolet light of wavelength 253 nm for 15 hours. During the irradiation process, the mixture was continuously stirred and argon gas was introduced at an amount of 320 ml / min. The temperature of the solid-liquid mixture was controlled at 30 degrees Celsius. The irradiated solid-liquid mixture was filtered and dried at 65 degrees Celsius for 4 hours to obtain fluorinated polyethylene resin slices.

[0035] Step 3: The fluorinated polyethylene resin slices obtained in step 2 and the polyethylene resin slices (weight-average molecular weight of 100,000) are used as raw materials, and composite melt spinning is performed in a composite spinning machine; the composite spinning machine includes two single-screw extruders, and the spinning temperature of the composite spinning machine is 230 degrees Celsius. The fluorinated polyethylene resin and the unmodified polyethylene resin are respectively added to different single-screw extruders to melt to form a melt, which is metered and transported to the composite spinning assembly by respectively equipped metering pumps, and extruded through a composite spinneret to obtain a continuous melt with fluorinated polyethylene as the skin layer and unmodified polyethylene resin as the core layer, in which the mass of fluorinated polyethylene accounts for 10 parts and the mass of unmodified polyethylene resin accounts for 90 parts; after air cooling and solidification, the modified polyethylene fiber with the skin layer of fluorinated polyethylene resin and the core layer of unmodified polyethylene resin is prepared by drawing 10 times at 113 degrees Celsius, in which the mass of the skin layer accounts for 10 parts and the mass of the core layer accounts for 90 parts.

[0036] Step 4: melt and soften the PTFE resin and isoparaffin solvent oil at 180 degrees Celsius using a twin-screw extruder, coat the surface of the modified polyethylene fiber obtained in step 3 through a melt coating process, and then deoil at 160 degrees Celsius to form a PTFE cortex. After cooling, PE / PTFE composite fibers are obtained, and the mass of the cortex PTFE accounts for 13.5% of the total fiber mass.

[0037] Example 4 This embodiment provides a PE / PTFE composite fiber that is anti-fouling and anti-biological attachment, and the preparation method thereof includes: Step 1: Using dioxane as a solvent, a benzophenone compound as shown in Formula 1, thioperoxydicarbonic acid as shown in Formula 2, and 2-(perfluorodecyl)ethyl methacrylate are mixed in a ratio of 1:1:140 to obtain a modified solution. A polyethylene resin chip with a weight average molecular weight of 150,000 is added to the modified solution, and the mass ratio of the polyethylene resin chip to 2-(perfluorodecyl)ethyl methacrylate is 1:70. High-purity argon gas is introduced at 150 ml / min, and stirred for 60 minutes to obtain a solid-liquid mixture.

[0038] Step 2: The solid-liquid mixture obtained in step 1 was irradiated with ultraviolet light of wavelength 253 nm for 20 hours. During the irradiation process, the mixture was continuously stirred and argon gas was introduced at a rate of 450 ml / min. The temperature of the solid-liquid mixture was controlled at 40 degrees Celsius. The irradiated solid-liquid mixture was filtered and dried at 70 degrees Celsius for 5 hours to obtain fluorinated polyethylene resin slices.

[0039] Step 3: The fluorinated polyethylene resin slices obtained in step 2 and the polyethylene resin slices (weight-average molecular weight of 150,000) are used as raw materials, and composite melt spinning is performed in a composite spinning machine; the composite spinning machine comprises two single-screw extruders, and the spinning temperature is 230 degrees Celsius. The fluorinated polyethylene resin and the unmodified polyethylene resin are respectively added to different single-screw extruders for melting to form a melt, which is metered and transported to the composite spinning assembly by respectively equipped metering pumps, and extruded through a composite spinneret to obtain a continuous melt with the fluorinated polyethylene as the skin layer and the unmodified polyethylene resin as the core layer, in which the mass of the fluorinated polyethylene accounts for 12 parts and the mass of the unmodified polyethylene resin accounts for 88 parts; after air cooling and solidification, the modified polyethylene fiber with the skin layer of the fluorinated polyethylene resin and the core layer of the unmodified polyethylene resin is prepared by drawing 12 times at 125 degrees Celsius, in which the mass of the skin layer accounts for 12 parts and the mass of the core layer accounts for 88 parts.

[0040] Step 4: melt and soften the PTFE resin and isoparaffin solvent oil at 137 degrees Celsius using a twin-screw extruder, coat the surface of the modified polyethylene fiber obtained in step 3 through a melt coating process, and then deoil at 158 ​​degrees Celsius to form a PTFE cortex. After cooling, PE / PTFE composite fibers are obtained, and the mass of the cortex PTFE accounts for 16.7% of the total fiber mass.

[0041] Comparative Example 1 The preparation method of this comparative example is as follows: Step 1: Spin polyethylene chips with a weight average molecular weight of 100,000 at 230 degrees Celsius, and draw them 8 times at 90 degrees Celsius to obtain polyethylene fibers.

[0042] Step 2: melt and soften the PTFE resin and isoparaffin solvent oil at 180 degrees Celsius using a twin-screw extruder, and coat the polyethylene fiber surface obtained in step 1 through a melt coating process, and then deoil at 165 degrees Celsius to form a PTFE cortex. After cooling, PE / PFA composite fibers are obtained, and the mass of the cortex PFA accounts for 13% of the total mass.

[0043] Comparative Example 2 The preparation method of this comparative example is as follows: Step 1: Spin polyethylene chips with a weight average molecular weight of 80,000 at 220 degrees Celsius, and draw them 10 times at 110 degrees Celsius to obtain polyethylene fibers.

[0044] Step 2: melt and soften the PTFE resin and isoparaffin solvent oil at 135 degrees Celsius using a twin-screw extruder, and coat the polyethylene fiber surface obtained in step 1 through a melt coating process, and then deoil at 180 degrees Celsius to form a PTFE cortex. After cooling, PE / PFA composite fibers are obtained, and the mass of the cortex PFA accounts for 12% of the total mass.

[0045] Comparative Example 3 The preparation method of this comparative example is as follows: Step 1: Spin polyethylene chips with a weight average molecular weight of 100,000 at 230 degrees Celsius, and draw them 8 times at 90 degrees Celsius to obtain polyethylene fibers.

[0046] Comparative Example 4 The preparation method of this comparative example is as follows: Polyethylene chips with a weight average molecular weight of 80,000 were spun at 220 degrees Celsius and stretched 10 times at 110 degrees Celsius to obtain polyethylene fibers.

[0047] Comparative Example 5 The difference between this comparative example and Example 1 is that the PTFE resin is replaced by an equal amount of polyvinylidene fluoride (PVDF).

[0048] Comparative Example 6 The difference between this comparative example and Example 1 is that the polyethylene resin chips with a weight average molecular weight of 100,000 are replaced by an equal amount of polypropylene (PP) with a weight average molecular weight of 100,000.

[0049] Comparative Example 7 The difference between this comparative example and Example 1 is that the polyethylene resin chips with a weight average molecular weight of 100,000 are replaced by an equal amount of polyamide (PA) with a weight average molecular weight of 100,000.

[0050] Performance testing The tensile properties of the composite fibers provided in the above embodiments and comparative examples were frequently tested using GB / T 14344-2022 "Test Method for Tensile Properties of Chemical Fiber Filaments". The amount of biological attachment on the surface of the composite fibers after immersion in seawater for half a year was calculated using the weighing method. The composite fibers were rubbed on 500-mesh sandpaper to evaluate the wear resistance. The test results are shown in Table 1: Table 1 Fiber properties of various embodiments and control examples It can be seen from the above table that the PE / PTFE composite fiber prepared by the present invention has excellent tensile strength, and its wear resistance is significantly improved compared with the products obtained by the conventional method, especially the wear resistance index is significantly improved, which shows that the method of the present invention can effectively improve the performance of the fiber.

[0051] In terms of the amount of biological adhesion on the surface after immersion in seawater for half a year, Examples 1 to 4, Comparative Examples 1 and 2 coated with PTFE cortex all show better anti-adhesion properties than Comparative Examples 3 and 4, which is mainly due to the low surface energy of PTFE material. At the same time, the amount of biological adhesion on the surface of the fiber coated with PVDF (Comparative Example 5) is also less than that of Example 1, indicating that the low surface energy of PTFE material is better than that of PVDF.

[0052] After simulating the friction environment in daily use, since the fibers of Examples 1 to 4 of the present invention adopt a new and improved process, the wear resistance can be effectively improved, and the fiber PTFE coating layer is retained, so the amount of biological attachment on the fiber surface is still very low, reflecting excellent and lasting anti-biological attachment; while in Comparative Examples 1 and 2, due to the low interaction force between the core layer polyethylene and the skin layer PTFE, they are easily separated under the friction in daily use, and the fiber surface will be damaged and roughened, causing the PTFE layer to fall off, thereby greatly affecting the original anti-biological attachment effect. This is the reason why the amount of biological attachment on the fiber surface of Comparative Examples 1 and 2 in the table is significantly increased after friction. At the same time, compared with Example 1, Comparative Examples 7 and 8, due to the different core layer materials used, although they have also undergone the same modification treatment, their wear resistance and mechanical properties under the same conditions are very weak.

[0053] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A PE / PTFE composite fiber for preventing fouling and biofouling, characterized in that: The PE / PTFE composite fiber is a layered structure, the inner layer is a modified polyethylene fiber, the outer layer is a PTFE coating layer, and the mass percentage of the PTFE coating layer is 3-35wt%; The tensile strength of the PE / PTFE composite fiber is above 5.8 cN / dtex, the amount of biological attachment on the surface of the fiber after being immersed in seawater for half a year is below 0.0012 g / m, and the amount of biological attachment on the surface of the fiber after being rubbed 5000 times and immersed in seawater for half a year is below 0.0022 g / m.

2. The anti-fouling and anti-biological attachment PE / PTFE composite fiber according to claim 1, characterized in that: The modified polyethylene fiber is obtained by composite melt spinning of polyethylene resin slices and fluorine-containing polyethylene resin slices, wherein the polyethylene resin serves as a core layer and the fluorine-containing polyethylene resin serves as a skin layer.

3. The anti-fouling and anti-biological attachment PE / PTFE composite fiber according to claim 2, characterized in that: In the modified polyethylene fiber, the core layer accounts for 5-90 parts by weight, and the skin layer accounts for 25-95 parts by weight.

4. A method for preparing the anti-fouling and anti-biological attachment PE / PTFE composite fiber according to any one of claims 1 to 3, characterized in that: It includes: The PTFE resin is blended with isoparaffin solvent oil, softened, and coated on the surface of the modified polyethylene fiber. After cooling, the PTFE coating layer is formed by deoiling to obtain the PE / PTFE composite fiber.

5. The method for preparing PE / PTFE composite fiber according to claim 4, characterized in that: The softening process includes: the PTFE resin is blended and melt-softened with the isoparaffin solvent oil at 100-300° C. through a screw extruder; preferably, the deoiling temperature during the formation of the PTFE coating layer is 80-250° C.

6. The method for preparing PE / PTFE composite fiber according to claim 4, characterized in that: The preparation method of the modified polyethylene fiber comprises: Dispersing fluorinated acrylate, benzophenone compounds, and alkyl esters containing thioperoxydicarbonate in an organic solvent to obtain a modified solution; Adding polyethylene resin chips to the modified liquid, stirring under an inert atmosphere to obtain a solid-liquid mixture, irradiating the solid-liquid mixture under ultraviolet light of 245-260 nm, continuously stirring and introducing an inert gas, and then filtering and drying to obtain fluorinated polyethylene resin chips; The polyethylene resin slices and the fluorine-containing polyethylene resin slices are composite melt-spun, and then heat-drawn to prepare modified polyethylene fibers with a skin layer of fluorine-containing polyethylene resin and a core layer of unmodified polyethylene resin.

7. The method for preparing PE / PTFE composite fiber according to claim 6, characterized in that: The fluorine-containing acrylate includes one or a combination of 2-(perfluorobutyl)ethyl methacrylate, 2-(perfluorooctyl)ethyl methacrylate, 2-(perfluorohexyl)ethyl methacrylate, 2-(perfluorodecyl)ethyl methacrylate, 2-perfluorooctylethyl acrylate, 3-(perfluoro-5-methylhexyl)-2-hydroxypropyl methacrylate, 1,1,1,3,3,3-hexafluoroisopropyl acrylate, and 2-(perfluorododecyl)ethyl acrylate.

8. The method for preparing PE / PTFE composite fiber according to claim 6, characterized in that: In the modified liquid, the molar ratio of the fluorinated acrylate, the benzophenone compound, and the alkyl ester containing thioperoxydicarbonate is (80-350):1:1; The benzophenone compound is a compound shown in Formula 1, and the alkyl ester containing thioperoxydicarbonate is a compound shown in Formula 2:

9. The method for preparing PE / PTFE composite fiber according to claim 6, characterized in that: In the process of preparing fluorine-containing polyethylene resin chips, the temperature of the solid-liquid mixture is controlled to be 10-60° C., and the ultraviolet lamp irradiation time is 3-48 hours.

10. The method for preparing PE / PTFE composite fiber according to claim 6, characterized in that: In the composite melt spinning process, the spinning temperature is 100-240° C., the hot drawing temperature is 80-130° C., and the drawing multiple is 3-15 times.

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