Polyvinylidene fluoride offshore photovoltaic cable material

Abstract

The invention relates to the technical field of polyvinylidene fluoride materials, in particular to a polyvinylidene fluoride offshore photovoltaic cable material. The polyvinylidene fluoride offshore photovoltaic cable material is prepared from the following raw materials in parts by mass: 40 to 70 parts of polyvinylidene fluoride, 20 to 50 parts of polyvinyl chloride, 5 to 15 parts of ethylene-trifluorochlor oethylene copolymer, 1 to 3 parts of perfluoroethyl vinyl ether, 0.1 to 1 part of dicumyl peroxide, 0.1 to 1 part of nano zinc oxide, 1 to 3 parts of calcium-zinc stabilizer, 10 to 30 parts of filler, 1 to 2 parts of lubricant and 0.5 to 1.5 parts of stearic acid. 1-2 parts of a plasticizer and 1-2 parts of a compatilizer. The requirement for long-term stable operation of an offshore photovoltaic cable in high-salt, high-humidity, high-temperature and strong-ultraviolet environments is effectively met, the requirement for long-term stable operation under severe offshore conditions is fully met, and meanwhile the preparation method is simple and suitable for large-scale application and popularization.

Description

Technical Field

[0001] This invention relates to the field of polyvinylidene fluoride (PVDF) materials technology, and more particularly to a PVDF marine photovoltaic cable material. Background Technology

[0002] The ocean covers more than 70% of the Earth's surface, possessing abundant solar energy resources. Its open, unobstructed nature and long hours of sunshine provide a natural advantage for improving the efficiency of photovoltaic (PV) power generation. As an emerging clean energy technology, offshore PV is gradually becoming a focus of industry attention. Cables, as key components for energy transmission in PV power generation systems, directly affect the stable operation of the entire system and the sustainable development of green energy. Therefore, developing high-performance cable materials suitable for offshore PV environments has significant research value and practical implications.

[0003] Because offshore photovoltaic (PV) cables are exposed to harsh marine environments characterized by high salinity, high humidity, high temperature, and strong ultraviolet radiation for extended periods, extremely high requirements are placed on the corrosion resistance, heat resistance, and UV aging resistance of the cable materials. However, existing cable materials have significant shortcomings in terms of resistance to damp heat and salt spray, making it difficult to meet the long-term stable operation requirements of offshore PV projects. Specifically, in high-temperature and high-humidity environments, traditional cable materials are prone to hydrolysis and oxidation, leading to a significant decrease in insulation performance and a reduction in mechanical strength, thus affecting energy transmission efficiency. In salt spray environments, a corrosion layer easily forms on the material surface, accelerating cable aging and failure. These problems not only increase maintenance costs but may also pose safety hazards, hindering the large-scale application of offshore PV technology.

[0004] Polyvinylidene fluoride (PVDF), a fluoropolymer, exhibits excellent chemical corrosion resistance and aging resistance due to its unique chemical structure, making it a potential candidate material for marine photovoltaic cables. However, its strong intermolecular forces, while improving physical and mechanical properties, also bring processing difficulties and cost issues. Therefore, how to optimize its processing technology and reduce costs while maintaining the excellent properties of PVDF, and how to develop a marine photovoltaic cable material with excellent resistance to damp heat and salt spray, are key problems that urgently need to be solved in this field. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by proposing a polyvinylidene fluoride (PVDF) marine photovoltaic cable material.

[0006] A polyvinylidene fluoride (PVDF) marine photovoltaic cable material, comprising the following raw materials by weight: 40-70 parts PVDF, 20-50 parts PVC, 5-15 parts ethylene-trifluorochloroethylene copolymer, 1-3 parts perfluoroethyl vinyl ether, 0.1-1 parts dicumyl peroxide, 0.1-1 parts nano zinc oxide, 1-3 parts calcium-zinc stabilizer, 10-30 parts filler, 1-2 parts lubricant, 0.5-1.5 parts stearic acid, 1-2 parts plasticizer, and 1-2 parts compatibilizer.

[0007] Preferably, the lubricant is at least one of silicone masterbatch, silicone phenol, and polyethylene wax.

[0008] Preferably, the plasticizer is at least one selected from dioctyl phthalate, diisooctyl phthalate, dibutyl phthalate, diheptyl phthalate, and diisodecyl phthalate.

[0009] Preferably, the compatibilizer is at least one of maleic anhydride-grafted polyethylene, maleic anhydride-grafted polypropylene, and maleic anhydride-grafted ethylene-vinyl acetate copolymer.

[0010] Preferably, the filler is at least one of titanium dioxide, carbon black, calcium carbonate, nano-silica, and activated silica.

[0011] Preferably, activated silica is prepared by the following specific steps: nano silica is ultrasonically dispersed in anhydrous ethanol for 10-30 min, glycidyl methacrylate and hydroxyethyl acrylate are added, and the mixture is stirred for 1-2 h under nitrogen protection. Potassium persulfate aqueous solution is added, and the mixture is stirred at 70-85℃ for 5-10 h. The mixture is then centrifuged, washed, vacuum dried, and pulverized.

[0012] Preferably, the mass ratio of nano-silica, glycidyl methacrylate, hydroxyethyl acrylate, and potassium persulfate is 10-30:1-5:1-5:0.03-0.15.

[0013] The preparation method of the above-mentioned polyvinylidene fluoride marine photovoltaic cable material includes the following steps: S1. After drying polyvinylidene fluoride and restoring it to room temperature, add ethylene-trifluorochloroethylene copolymer and perfluoroethyl vinyl ether for premixing for 1-3 min, then add dicumyl peroxide and nano zinc oxide and continue mixing for 5-15 min. Melt blend and extrude at 180-190℃, and then water-cool and pelletize to obtain polyvinylidene fluoride blend. S2. Premix the polyvinylidene fluoride blend, polyvinyl chloride, calcium zinc stabilizer, filler, lubricant, stearic acid, plasticizer, and compatibilizer for 2-6 minutes, knead at 182-190℃ for 10-18 minutes, and granulate by extrusion at 130-150℃.

[0014] Preferably, in S1, the drying temperature of polyvinylidene fluoride is 80-100℃, and the drying time is 1-2h.

[0015] Preferably, S2 further includes: extruding and granulating the material before extruding it in a wire extruder, wherein the temperatures of each zone of the wire extruder are 140-150℃, 155-160℃, 165-170℃, and 175-180℃ respectively.

[0016] Beneficial effects: This invention introduces ethylene-trifluorochloroethylene copolymer into polyvinylidene fluoride to form flexible segments, which can reduce intermolecular forces and improve processing performance. Meanwhile, the fluorinated groups of perfluoroethyl vinyl ether form a dense fluorine protective layer on the material surface, effectively blocking the penetration of water molecules and salt ions, and significantly enhancing salt spray resistance.

[0017] The activated silica used in this invention has a high interfacial bonding strength between glycidyl methacrylate and polyvinylidene fluoride blends, and the silica particles can enhance the mechanical interlocking between them and the matrix. The hydroxyl groups of hydroxyethyl acrylate form hydrogen bonds with the polyvinyl chloride molecular chains, which synergistically promote the uniform dispersion of nano-silica in the matrix, which not only significantly enhances the material's resistance to damp heat, but also ensures excellent dimensional stability of the material.

[0018] This invention utilizes a dense interfacial protective layer formed by a polyvinylidene fluoride blend and activated grafted nano-silica. The nano-silica effectively fills the gaps between polymer molecular chains, reduces the penetration path of water molecules, and effectively prevents water molecules from diffusing into the material. It significantly inhibits the occurrence of hydrolysis reactions under high temperature and high humidity environments. At the same time, the activated grafted nano-silica enhances the interfacial bonding force between the filler and the matrix through chemical bonding, prevents the generation of interfacial defects, effectively inhibits the formation of channels for salt corrosion, and further enhances salt spray resistance.

[0019] This invention effectively solves the long-term stable operation requirement of offshore photovoltaic cables under high salt, high humidity, high temperature and strong ultraviolet radiation environments, fully meets the requirements for long-term stable operation under harsh offshore conditions, and the preparation method is simple and suitable for large-scale promotion and application. Attached Figure Description

[0020] Figure 1 The image shows a comparison of the tensile strength and elongation at break of the marine photovoltaic cable materials obtained in Example 5 and Comparative Examples 1-2.

[0021] Figure 2 The graph shows a comparison of the tensile strength retention rate and tensile strength change rate after wet heat aging and salt spray corrosion of the marine photovoltaic cable materials obtained in Example 5 and Comparative Examples 1-2. Detailed Implementation

[0022] The present invention will be further explained below with reference to specific embodiments.

[0023] The polyvinylidene fluoride used below is sourced from Arkema, France, and its grade is PVDF 2850-07. The polyvinyl chloride used below is sourced from Manner Plastics, USA, and its grade is PVC X4260. The ethylene-trifluorochloroethylene copolymer used below is sourced from Solvay, France, and its grade is ECTFE 6514. The perfluoroethyl vinyl ether used below is from Zhongshan Mouxin Chemical Co., Ltd. The silicone masterbatch used below is sourced from Dow Corning, and its grade is MB50-002.

[0024] Example 1 A polyvinylidene fluoride (PVDF) marine photovoltaic cable material, the raw materials of which include: 400g PVDF, 200g PVC, 50g ethylene-chlorotrifluoroethylene copolymer, 10g perfluoroethyl vinyl ether, 1g dicumyl peroxide, 1g nano zinc oxide, 10g calcium zinc stabilizer, 100g titanium dioxide, 10g silicone masterbatch, 5g stearic acid, 10g dioctyl phthalate, and 10g maleic anhydride-grafted polypropylene.

[0025] The preparation method of the above-mentioned polyvinylidene fluoride marine photovoltaic cable material includes the following steps: S1. Dry polyvinylidene fluoride at 80℃ for 1 hour, restore to room temperature, add ethylene-trifluorochloroethylene copolymer and perfluoroethyl vinyl ether, premix for 1 minute at a premixing speed of 500 r / min, add dicumyl peroxide and nano zinc oxide, continue mixing for 5 minutes, feed into a twin-screw extruder, melt blend extrusion at 180℃, water-cooled pelletizing to obtain polyvinylidene fluoride blend; S2. Add the polyvinylidene fluoride blend, polyvinyl chloride, calcium zinc stabilizer, titanium dioxide, silicone masterbatch, stearic acid, dioctyl phthalate, and maleic anhydride-grafted polypropylene to a mixer and premix for 2 minutes. Then add it to a kneader and mix at 182°C for 10 minutes. Feed it into a single-screw extruder and extrude and granulate at 130°C. Then add it to a wire rod extruder and extrude it. The temperature zones of the wire rod extruder are 140°C, 155°C, 165°C, and 175°C respectively. Cool and wind up.

[0026] Example 2 A polyvinylidene fluoride (PVDF) marine photovoltaic cable material, the raw materials of which include: 700g PVDF, 500g PVC, 150g ethylene-chlorotrifluoroethylene copolymer, 30g perfluoroethyl vinyl ether, 10g dicumyl peroxide, 10g nano zinc oxide, 30g calcium-zinc stabilizer, 300g nano calcium carbonate, 20g silicone masterbatch, 15g stearic acid, 20g dioctyl phthalate, and 20g maleic anhydride-grafted ethylene-vinyl acetate copolymer.

[0027] The preparation method of the above-mentioned polyvinylidene fluoride marine photovoltaic cable material includes the following steps: S1. Dry polyvinylidene fluoride at 100℃ for 2 hours, restore to room temperature, add ethylene-trifluorochloroethylene copolymer and perfluoroethyl vinyl ether, premix for 3 minutes at a premixing speed of 1200 r / min, add dicumyl peroxide and nano zinc oxide, continue mixing for 15 minutes, feed into a twin-screw extruder, melt blend extrusion at 190℃, water-cooled pelletizing to obtain polyvinylidene fluoride blend; S2. Add the polyvinylidene fluoride blend, polyvinyl chloride, calcium-zinc stabilizer, nano-calcium carbonate, silicone masterbatch, stearic acid, dioctyl phthalate, and maleic anhydride-grafted ethylene-vinyl acetate copolymer to a mixer and premix for 6 minutes. Then add it to a kneader and mix at 190°C for 18 minutes. Feed it into a single-screw extruder and granulate it at 150°C. Then add it to a wire rod extruder and extrude it. The temperature zones of the wire rod extruder are 150°C, 160°C, 170°C, and 180°C respectively. Cool and wind up.

[0028] Example 3 A polyvinylidene fluoride (PVDF) marine photovoltaic cable material, the raw materials of which include: 500g PVDF, 400g PVC, 80g ethylene-chlorotrifluoroethylene copolymer, 25g perfluoroethyl vinyl ether, 2g dicumyl peroxide, 8g nano zinc oxide, 15g calcium zinc stabilizer, 250g activated silica, 13g silicone masterbatch, 13g stearic acid, 12g dioctyl phthalate, and 18g maleic anhydride-grafted ethylene-vinyl acetate copolymer.

[0029] Activated silica is prepared using the following specific steps: 150g of nano silica is placed in 1200g of anhydrous ethanol and ultrasonically dispersed for 15min at an ultrasonic frequency of 88kHz. 20g of glycidyl methacrylate and 40g of hydroxyethyl acrylate are added, and the mixture is stirred for 80min under nitrogen protection. 25g of 3% potassium persulfate aqueous solution is added, and the mixture is stirred at 80℃ for 7h. After centrifugation, washing, vacuum drying, and pulverization, the silica is prepared.

[0030] The preparation method of the above-mentioned polyvinylidene fluoride marine photovoltaic cable material includes the following steps: S1. Dry polyvinylidene fluoride at 95℃ for 80 min, restore to room temperature, add ethylene-trifluorochloroethylene copolymer and perfluoroethyl vinyl ether premix for 2 min at a premixing speed of 1000 r / min, add dicumyl peroxide and nano zinc oxide, continue mixing for 8 min, feed into a twin-screw extruder, melt blend extrusion at 188℃, water-cooled pelletizing to obtain polyvinylidene fluoride blend; S2. Add the polyvinylidene fluoride blend, polyvinyl chloride, calcium zinc stabilizer, activated silica, silicone masterbatch, stearic acid, dioctyl phthalate, and maleic anhydride-grafted ethylene-vinyl acetate copolymer to a mixer and premix for 3 minutes. Then add it to a kneader and mix at 188°C for 12 minutes. Feed it into a single-screw extruder and extrude and granulate at 145°C. Then add it to a wire rod extruder and extrude it. The temperature zones of the wire rod extruder are 142°C, 158°C, 166°C, and 178°C respectively. Cool and wind up.

[0031] Example 4 A polyvinylidene fluoride (PVDF) marine photovoltaic cable material, the raw materials of which include: 600g PVDF, 300g PVC, 120g ethylene-trifluorochloroethylene copolymer, 15g perfluoroethyl vinyl ether, 8g dicumyl peroxide, 2g nano zinc oxide, 25g calcium zinc stabilizer, 150g activated silica, 17g polyethylene wax, 7g stearic acid, 18g dioctyl phthalate, and 12g maleic anhydride-grafted polyethylene.

[0032] Activated silica is prepared using the following specific steps: 250g of nano silica is placed in 800g of anhydrous ethanol and ultrasonically dispersed for 25min at an ultrasonic frequency of 82kHz. 40g of glycidyl methacrylate and 20g of hydroxyethyl acrylate are added, and the mixture is stirred for 100min under nitrogen protection. 15g of 5% potassium persulfate aqueous solution is added, and the mixture is stirred at 75℃ for 9h. After centrifugation, washing, vacuum drying, and pulverization, the silica is prepared.

[0033] The preparation method of the above-mentioned polyvinylidene fluoride marine photovoltaic cable material includes the following steps: S1. Dry polyvinylidene fluoride at 85℃ for 100 min, restore to room temperature, add ethylene-trifluorochloroethylene copolymer and perfluoroethyl vinyl ether, premix for 2 min at a premixing speed of 600 r / min, add dicumyl peroxide and nano zinc oxide, continue mixing for 12 min, feed into a twin-screw extruder, melt blend extrusion at 182℃, water-cooled pelletizing to obtain polyvinylidene fluoride blend; S2. Add the polyvinylidene fluoride blend, polyvinyl chloride, calcium zinc stabilizer, activated silica, polyethylene wax, stearic acid, dioctyl phthalate, and maleic anhydride-grafted polyethylene to a mixer and premix for 5 minutes. Then add it to a kneader and mix at 184°C for 16 minutes. Feed it into a single-screw extruder and granulate it at 135°C. Then add it to a wire rod extruder and extrude it. The temperatures of each zone of the wire rod extruder are 148°C, 156°C, 168°C, and 176°C, respectively. Cool and wind up.

[0034] Example 5 A polyvinylidene fluoride (PVDF) marine photovoltaic cable material, the raw materials of which include: 550g PVDF, 350g PVC, 100g ethylene-trifluorochloroethylene copolymer, 20g perfluoroethyl vinyl ether, 5g dicumyl peroxide, 5g nano zinc oxide, 20g calcium-zinc stabilizer, 200g activated silica, 15g polyethylene wax, 10g stearic acid, 15g dioctyl phthalate, and 15g maleic anhydride-grafted polyethylene.

[0035] Activated silica is prepared by the following specific steps: 200g of nano silica is placed in 1000g of anhydrous ethanol and ultrasonically dispersed for 20min at an ultrasonic frequency of 85kHz. 30g of glycidyl methacrylate and 30g of hydroxyethyl acrylate are added, and the mixture is stirred for 90min under nitrogen protection. 20g of 4% potassium persulfate aqueous solution is added, and the mixture is stirred at 78℃ for 8h. After centrifugation, washing, vacuum drying, and pulverization, the silica is prepared.

[0036] The preparation method of the above-mentioned polyvinylidene fluoride marine photovoltaic cable material includes the following steps: S1. Dry polyvinylidene fluoride at 90℃ for 90 min, restore to room temperature, add ethylene-trifluorochloroethylene copolymer and perfluoroethyl vinyl ether for 2 min, premix at 800 r / min, add dicumyl peroxide and nano zinc oxide, continue mixing for 10 min, feed into a twin-screw extruder, melt blend extrusion at 185℃, water-cooled pelletizing to obtain polyvinylidene fluoride blend; S2. Add the polyvinylidene fluoride blend, polyvinyl chloride, calcium zinc stabilizer, activated silica, polyethylene wax, stearic acid, dioctyl phthalate, and maleic anhydride-grafted polyethylene to a mixer and premix for 4 minutes. Then add it to a kneader and mix at 185°C for 15 minutes. Feed it into a single-screw extruder and granulate it at 140°C. Then add it to a wire rod extruder and extrude it. The temperatures of each zone of the wire rod extruder are 145°C, 157°C, 167°C, and 177°C, respectively. Cool and wind up.

[0037] Comparative Example 1 A marine photovoltaic cable material, the raw materials of which include: 550g of polyvinylidene fluoride, 355g of polyvinyl chloride, 100g of ethylene-trifluorochloroethylene copolymer, 25g of perfluoroethyl vinyl ether, 20g of calcium zinc stabilizer, 200g of activated silica, 15g of polyethylene wax, 10g of stearic acid, 15g of dioctyl phthalate, and 15g of maleic anhydride-grafted polyethylene.

[0038] Activated silica is prepared by the following specific steps: 200g of nano silica is placed in 1000g of anhydrous ethanol and ultrasonically dispersed for 20min at an ultrasonic frequency of 85kHz. 30g of glycidyl methacrylate and 30g of hydroxyethyl acrylate are added, and the mixture is stirred for 90min under nitrogen protection. 20g of 4% potassium persulfate aqueous solution is added, and the mixture is stirred at 78℃ for 8h. After centrifugation, washing, vacuum drying, and pulverization, the silica is prepared.

[0039] The preparation method of the above-mentioned marine photovoltaic cable material includes the following steps: polyvinylidene fluoride, ethylene-trifluorochloroethylene copolymer, perfluoroethyl vinyl ether, polyvinyl chloride, calcium zinc stabilizer, activated silica, polyethylene wax, stearic acid, dioctyl phthalate, and maleic anhydride grafted polyethylene are added to a mixer for premixing for 4 minutes, then added to a kneader and mixed at 185°C for 15 minutes. The mixture is then fed into a single-screw extruder and extruded and granulated at 140°C. Next, it is added to a wire extruder for extrusion. The temperatures of each zone of the wire extruder are 145°C, 157°C, 167°C, and 177°C, respectively. After cooling, the wire is wound up.

[0040] Comparative Example 2 A marine photovoltaic cable material, the raw materials of which include: 550g of polyvinylidene fluoride, 350g of polyvinyl chloride, 100g of ethylene-trifluorochloroethylene copolymer, 20g of perfluoroethyl vinyl ether, 5g of dicumyl peroxide, 5g of nano zinc oxide, 20g of calcium zinc stabilizer, 200g of nano silica, 15g of polyethylene wax, 10g of stearic acid, 15g of dioctyl phthalate, and 15g of maleic anhydride-grafted polyethylene.

[0041] The preparation method of the above-mentioned marine photovoltaic cable material includes the following steps: S1. Dry polyvinylidene fluoride at 90℃ for 90 min, restore to room temperature, add ethylene-trifluorochloroethylene copolymer and perfluoroethyl vinyl ether for 2 min, premix at 800 r / min, add dicumyl peroxide and nano zinc oxide, continue mixing for 10 min, feed into a twin-screw extruder, melt blend extrusion at 185℃, water-cooled pelletizing to obtain polyvinylidene fluoride blend; S2. Add the polyvinylidene fluoride blend, polyvinyl chloride, calcium-zinc stabilizer, nano silica, polyethylene wax, stearic acid, dioctyl phthalate, and maleic anhydride-grafted polyethylene to a mixer and premix for 4 minutes. Then add it to a kneader and mix at 185°C for 15 minutes. Feed it into a single-screw extruder and granulate it at 140°C. Then add it to a wire rod extruder and extrude it. The temperatures of each zone of the wire rod extruder are 145°C, 157°C, 167°C, and 177°C, respectively. Cool and wind up.

[0042] The tensile strength and elongation at break of the marine photovoltaic cable materials obtained in Example 5 and Comparative Examples 1-2 were determined in accordance with GB / T 2951.11-2008 "General Test Methods for Insulation and Sheath Materials of Cables and Optical Fibers - Part 11: General Test Methods for Thickness and Dimensional Measurement and Mechanical Properties".

[0043] like Figure 1 As shown, the marine photovoltaic cable material obtained in Example 5 has the highest tensile strength and elongation at break, which are significantly better than those in Comparative Examples 1-2.

[0044] The marine photovoltaic cable materials obtained in Example 5 and Comparative Examples 1-2 were placed in a damp heat aging test chamber at 85°C and 85% humidity for 168 hours, and their tensile strength was tested. The tensile strength retention rate was calculated. Tensile strength retention rate = tensile strength after damp heat aging ÷ original tensile strength × 100%.

[0045] Perform a 30-day cyclic corrosion test according to Test Method 1 in IEC 60068-2-5, test the tensile strength, and calculate the rate of change of tensile strength. Rate of change of tensile strength = (Original tensile strength - Tensile strength after salt spray corrosion) ÷ Original tensile strength × 100%.

[0046] like Figure 2 As shown, the marine photovoltaic cable material obtained in Example 5 exhibits the highest tensile strength retention rate after wet heat aging, but the lowest tensile strength change rate after salt spray corrosion, which is significantly better than Comparative Examples 1-2.

[0047] The reasons for the above results are as follows: This invention introduces ethylene-trifluorochloroethylene copolymer into polyvinylidene fluoride (PVDF) to form flexible segments, which reduces intermolecular forces and improves processing performance. Meanwhile, the fluorinated groups of perfluoroethyl vinyl ether form a dense fluorine protective layer on the material surface, effectively blocking the penetration of water molecules and salt ions, significantly enhancing salt spray resistance. The activated silica used in this invention exhibits high interfacial bonding strength between glycidyl methacrylate and the PVDF blend, and the silica particles enhance the mechanical interlocking between them and the matrix. The hydroxyl groups of hydroxyethyl acrylate form hydrogen bonds with the PVDF molecular chains, synergistically promoting the uniform dispersion of nano-silica in the matrix, significantly enhancing the material's resistance to damp heat and ensuring excellent dimensional stability. This invention utilizes a dense interfacial protective layer formed by a polyvinylidene fluoride blend and activated grafted nano-silica. The nano-silica effectively fills the gaps between polymer molecular chains, reduces the penetration path of water molecules, and effectively prevents water molecules from diffusing into the material. It significantly inhibits the occurrence of hydrolysis reactions under high temperature and high humidity environments. At the same time, the activated grafted nano-silica enhances the interfacial bonding force between the filler and the matrix through chemical bonding, prevents the generation of interfacial defects, effectively inhibits the formation of channels for salt corrosion, and further enhances salt spray resistance.

[0048] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A polyvinylidene fluoride (PVDF) marine photovoltaic cable material, characterized in that, The raw materials, by weight, include: 40-70 parts polyvinylidene fluoride, 20-50 parts polyvinyl chloride, 5-15 parts ethylene-trifluorochloroethylene copolymer, 1-3 parts perfluoroethyl vinyl ether, 0.1-1 parts dicumyl peroxide, 0.1-1 parts nano zinc oxide, 1-3 parts calcium-zinc stabilizer, 10-30 parts filler, 1-2 parts lubricant, 0.5-1.5 parts stearic acid, 1-2 parts plasticizer, and 1-2 parts compatibilizer.

2. The polyvinylidene fluoride marine photovoltaic cable material according to claim 1, characterized in that, The lubricant is at least one of silicone masterbatch, silicone phenol, and polyethylene wax.

3. The polyvinylidene fluoride marine photovoltaic cable material according to claim 1, characterized in that, The plasticizer is at least one of dioctyl phthalate, diisooctyl phthalate, dibutyl phthalate, diheptyl phthalate, and diisodecyl phthalate.

4. The polyvinylidene fluoride marine photovoltaic cable material according to claim 1, characterized in that, The compatibilizer is at least one of maleic anhydride-grafted polyethylene, maleic anhydride-grafted polypropylene, and maleic anhydride-grafted ethylene-vinyl acetate copolymer.

5. The polyvinylidene fluoride marine photovoltaic cable material according to claim 1, characterized in that, The filler is at least one of titanium dioxide, carbon black, calcium carbonate, nano silica, and activated silica.

6. The polyvinylidene fluoride marine photovoltaic cable material according to claim 5, characterized in that, Activated silica is prepared by the following specific steps: nano silica is ultrasonically dispersed in anhydrous ethanol for 10-30 min, glycidyl methacrylate and hydroxyethyl acrylate are added, and the mixture is stirred for 1-2 h under nitrogen protection. Potassium persulfate aqueous solution is added, and the mixture is stirred at 70-85℃ for 5-10 h. The mixture is then centrifuged, washed, vacuum dried, and pulverized.

7. The polyvinylidene fluoride marine photovoltaic cable material according to claim 6, characterized in that, The mass ratio of nano silica, glycidyl methacrylate, hydroxyethyl acrylate, and potassium persulfate is 10-30:1-5:1-5:0.03-0.

15.

8. A method for preparing polyvinylidene fluoride marine photovoltaic cable material as described in any one of claims 1-7, characterized in that, Includes the following steps: S1. After drying polyvinylidene fluoride and restoring it to room temperature, add ethylene-trifluorochloroethylene copolymer and perfluoroethyl vinyl ether for premixing for 1-3 min, then add dicumyl peroxide and nano zinc oxide and continue mixing for 5-15 min. Melt blend and extrude at 180-190℃, and then water-cool and pelletize to obtain polyvinylidene fluoride blend. S2. Premix the polyvinylidene fluoride blend, polyvinyl chloride, calcium zinc stabilizer, filler, lubricant, stearic acid, plasticizer, and compatibilizer for 2-6 minutes, knead at 182-190℃ for 10-18 minutes, and granulate by extrusion at 130-150℃.

9. The method for preparing polyvinylidene fluoride marine photovoltaic cable material according to claim 8, characterized in that, In S1, the drying temperature of polyvinylidene fluoride is 80-100℃, and the drying time is 1-2h.

10. The method for preparing polyvinylidene fluoride marine photovoltaic cable material according to claim 8, characterized in that, S2 also includes: extruding and granulating the material, and then extruding it in a wire extruder, wherein the temperatures of each zone of the wire extruder are 140-150℃, 155-160℃, 165-170℃, and 175-180℃ respectively.

Images