A cable material used in seawater and a preparation method thereof

Abstract

The present application relates to the technical field of cable processing, and more specifically, to a cable material for use in seawater and a preparation method thereof. The cable for use in seawater is prepared from the following raw materials in parts by weight: 38-42 parts of polyvinyl chloride, 25-30 parts of ethylene-polyvinyl alcohol copolymer, 5-10 parts of ethylene-propylene rubber, 18-23 parts of heavy calcium carbonate, 2-4 parts of tetrapod-shaped zinc oxide whiskers, 5-7 parts of montmorillonite, 3-6 parts of stabilizer, 8-12 parts of plasticizer, 0.2-0.5 parts of antioxidant and 0.8-1.2 parts of lubricant. The cable for use in seawater is prepared by preparing the above formula, so that the cable for use in seawater has good tensile strength, elongation at break, insulation, corrosion resistance, weather resistance and low temperature resistance, and can be used in seawater for a long time.

Description

Technical Field

[0001] The present application relates to the technical field of cable processing, and more specifically, to a cable material for use in seawater and a preparation method thereof. Background Art

[0002] Waterproof cables are often used in outdoor equipment, underwater equipment, underground pipelines, tunnels, bridges, ships, vehicles and other places that require waterproofing, moisture-proofing and corrosion-proofing. Waterproof cables with different functions are prepared according to different use environments. For example, waterproof cables used in marine engineering must be able to adapt to the low temperature and pressure of seawater.

[0003] At present, marine waterproof cables mainly include polyvinyl chloride insulated waterproof cables, polyethylene insulated waterproof cables and cross-linked polyethylene insulated waterproof cables. Among them, polyvinyl chloride insulated waterproof cables have excellent waterproof performance, mechanical strength, electrical performance and low cost, and are widely used in marine engineering.

[0004] However, in seawater environments, PVC will be corroded by chloride ions and other marine chemicals, which will accelerate the aging of PVC and cause its insulation performance to deteriorate. Therefore, in seawater applications, PVC insulated cables may require more frequent inspections and replacements. Summary of the invention

[0005] In order to solve the problem that polyvinyl chloride may be corroded by chloride ions and other marine chemicals, which accelerates the aging of polyvinyl chloride and causes its insulation performance to deteriorate, the present application provides a cable material for use in seawater and a preparation method thereof.

[0006] In the first aspect, the present application provides a cable material for use in seawater, using the following technical solution:

[0007] A cable material for use in seawater is prepared from the following raw materials in parts by weight:

[0008] 38-42 parts of polyvinyl chloride

[0009] Ethylene-polyvinyl alcohol copolymer 25-30 parts

[0010] 5-10 parts of EPDM

[0011] Heavy calcium carbonate 18-23 parts

[0012] 2-4 parts of tetrapod-shaped zinc oxide whiskers

[0013] 5-7 parts of montmorillonite

[0014] 3-6 parts of stabilizer

[0015] Plasticizer 8-12 parts

[0016] Antioxidant 0.2-0.5 parts

[0017] Lubricant 0.8-1.2 parts.

[0018] By adopting the above technical scheme, the cable material prepared for use in seawater has good anti-aging performance, waterproof performance, and durability, and can be used for a long time under seawater conditions. In this application, the waterproofness and corrosion resistance of polyvinyl chloride can be further improved by adopting polyvinyl chloride, ethylene-polyvinyl alcohol copolymer and ethylene-propylene rubber. Among them, ethylene-propylene rubber has excellent weather resistance, ozone resistance, chemical corrosion resistance and electrical insulation, and has good anti-aging performance. The compound use of polyvinyl chloride and ethylene-propylene rubber can resist the erosion of chemicals in seawater and improve the service life of the cable; ethylene-polyvinyl alcohol copolymer has good barrier properties. The use of ethylene-polyvinyl alcohol copolymer, polyvinyl chloride and ethylene-propylene rubber can improve the barrier performance of the cable to seawater, and further prevent chloride ions and other chemicals in seawater from shortening the service life of the cable.

[0019] At the same time, by adding heavy calcium carbonate, tetrapod-shaped zinc oxide whiskers and montmorillonite, the physical and mechanical properties and mechanical properties of the cable are further improved, and the stability of the cable is improved.

[0020] Lubricants can improve the processing performance of polyvinyl chloride, ethylene-polyvinyl alcohol copolymer, ethylene-propylene rubber, heavy calcium carbonate, tetrapod-shaped zinc oxide whisker and montmorillonite, improve the processing efficiency of cable materials, and at the same time improve the stability of cables and extend the service life of cables.

[0021] By adding stabilizers, the service life of the cable can be extended and the stability of its electrical and mechanical properties can be maintained; by adding plasticizers, the hardness of the cable can be reduced, and its low temperature resistance and impact resistance can be improved, thereby enhancing the adaptability and reliability of the cable in seawater; by adding antioxidants, the antioxidant properties of the cable can be improved and the service life of the cable can be extended.

[0022] Preferably, the EPDM rubber is modified EPDM, which is prepared by the following method: 5-10 parts by weight of EPDM, 3-5 parts by weight of polyethylene and 0.5-1 parts by weight of an initiator are mixed to obtain a mixture, and the mixture is added to an extruder at 150-200°C and a pressure of 10-12MPa, and extruded and granulated to obtain the modified EPDM.

[0023] By adopting the above technical scheme, the compatibility of EPDM with polyvinyl chloride and ethylene-vinyl alcohol copolymer is improved, and the low temperature resistance and stability of EPDM are improved, and the service life of the cable in seawater is further improved. Polyethylene has good low temperature resistance, and the minimum operating temperature can reach -100 to -70°C. It has good chemical stability and can withstand corrosion from most acids and salts. Under specific temperature and pressure, EPDM and polyethylene are mixed with an initiator and subjected to a grafting reaction. During the reaction, the free radicals of EPDM and polyethylene react with each other's molecular chains to form a grafted copolymer, which improves the low temperature resistance and weather resistance of EPDM, thereby improving the weather resistance, low temperature resistance and corrosion resistance of the cable.

[0024] Preferably, the weight ratio of the polyvinyl chloride, the ethylene-polyvinyl alcohol copolymer and the ethylene-propylene rubber is 40:(28-30):8.

[0025] By adopting the above technical scheme, the dosage of polyvinyl chloride, ethylene-polyvinyl alcohol copolymer and ethylene-vinyl alcohol copolymer is optimized, and the weather resistance, waterproofness and insulation of the cable are further improved. At the same time, the cable is ensured to have excellent tensile strength and flexibility, and is more suitable for complex use environment in seawater.

[0026] Preferably, the stabilizer is obtained by mixing N-cyclohexylmaleimide, calcium zinc composite stabilizer and oxidized rare earth in a weight ratio of (5-9):2:(4-6).

[0027] By adopting the above technical solutions, the stability of cable materials can be enhanced, and the low temperature resistance, oxidation resistance and weather resistance can be improved, thereby extending the service life of the cable. N-cyclohexylmaleimide, as a highly efficient stabilizer, can effectively prevent the decomposition of cable materials and maintain the stability of their structure. The calcium-zinc composite stabilizer has excellent weather resistance and electrical properties, which can further improve the durability and safety of the cable. Oxidized rare earth stabilizers can form a stable oxide layer in the cable material to prevent oxygen and moisture from corroding the cable, thereby enhancing its oxidation resistance and water resistance. The combination of the three can further improve the comprehensive performance of the cable.

[0028] Preferably, the plasticizer is obtained by mixing epoxy fatty acid methyl ester and vinyl acetate in a weight ratio of (6-9):4.

[0029] By adopting the above technical scheme, the weather resistance, low temperature resistance, waterproofness and mechanical properties of the cable can be further improved. Epoxy fatty acid methyl ester has good light resistance and electrical properties, which can improve the high temperature resistance and electrical insulation performance of the cable. Vinyl acetate has excellent plasticizing effect and cold resistance, which can increase the softness and cold resistance of the cable and improve its flexibility in low temperature environment. By compounding epoxy fatty acid methyl ester and vinyl acetate, the advantages of both can be comprehensively utilized to obtain a plasticizer with better performance. This compound plasticizer can not only improve the processing performance and use performance of the cable, but also improve the heat resistance, cold resistance, aging resistance, etc. of the cable, thereby extending the service life of the cable.

[0030] Preferably, the ethylene content in the ethylene-polyvinyl alcohol copolymer is 30-40 mol%.

[0031] By adopting the above technical solution, the ethylene content in ethylene-vinyl alcohol copolymer is optimized, and the waterproofness, flexibility, weather resistance and insulation of the cable are further improved. When the ethylene content is high, it helps to improve the insulation performance and toughness of the cable, but too high ethylene content may reduce the weather resistance of the cable, thereby affecting the service life and stability of the cable. When the ethylene content is low, the flexibility and waterproofness of the cable will be affected, which will accelerate the aging of the cable.

[0032] Preferably, the average molecular weight of the polyvinyl chloride is 40,000-90,000.

[0033] By adopting the above technical solution, the average molecular weight of polyvinyl chloride is optimized, its processing performance is improved, and at the same time, the mechanical strength, chemical corrosion resistance and stability of the cable are further improved, thereby extending the service life of the cable.

[0034] Preferably, the average length of the needles in the four-needle zinc oxide whiskers is 200-300 microns.

[0035] By adopting the above technical solution, the length of the needles in the four-needle zinc oxide whiskers is further optimized, the mechanical strength of the cable is further improved, and the service life of the cable is extended.

[0036] Preferably, the montmorillonite includes at least one of calcium-based montmorillonite, sodium-based montmorillonite and sodium-calcium-based montmorillonite.

[0037] By adopting the above technical solution, the stability and acid resistance of the cable in seawater can be further improved, and at the same time the insulation performance of the cable can be enhanced and the service life of the cable can be increased.

[0038] In a second aspect, the present application provides a method for preparing a cable material for use in seawater, using the following technical solution:

[0039] A method for preparing a cable material for use in seawater, comprising the following preparation steps:

[0040] S1, putting polyvinyl chloride, ethylene-propylene rubber and ethylene-polyvinyl alcohol copolymer into an internal mixer for mixing at a mixing temperature of 70-80° C. and a mixing speed of 1500-1800 r / min to obtain a mixture A;

[0041] S2. Mixing mixture A, heavy calcium carbonate, tetrapod-shaped zinc oxide whisker, montmorillonite, stabilizer, plasticizer, antioxidant and lubricant at a mixing temperature of 80-100° C. and a mixing speed of 2500-3000 r / min, and discharging to obtain mixture B; S3. Mixing mixture B at 180-200° C., mixing and extruding, and then pressing and molding in a hot press to obtain a cable material for use in seawater.

[0042] By adopting the above technical scheme, polyvinyl chloride, ethylene-propylene rubber, ethylene-polyvinyl alcohol copolymer, heavy calcium carbonate, tetrapod-shaped zinc oxide whisker, montmorillonite, stabilizer, plasticizer, antioxidant and lubricant are fully and evenly mixed to obtain a cable material for use in seawater with a stable structure and excellent waterproof, weather-resistant and low-temperature resistance, which can be used in seawater for a long time.

[0043] In summary, this application has the following beneficial effects:

[0044] 1. In the present application, polyvinyl chloride, ethylene-polyvinyl alcohol copolymer, ethylene-propylene rubber, heavy calcium carbonate, tetrapod-shaped zinc oxide whisker, montmorillonite, stabilizer, plasticizer, antioxidant and lubricant are used to prepare cable materials for use in seawater, which can greatly improve the waterproofness, insulation, weather resistance, tensile strength, elongation at break and low temperature resistance of the cable, so that it can be used in seawater for a long time.

[0045] 2. In the present application, EPDM, polyethylene and an initiator are reacted at a specific temperature and pressure to obtain a modified EPDM, thereby improving the compatibility of the EPDM with polyvinyl chloride and ethylene-vinyl alcohol copolymer, while improving the low-temperature resistance of the EPDM, further increasing the service life of the cable in seawater. DETAILED DESCRIPTION

[0046] Example

[0047] Example 1

[0048] A cable material for use in seawater is prepared by the following method:

[0049] S1, 380 g of polyvinyl chloride (average molecular weight of 40,000), 50 g of ethylene-propylene rubber and 250 g of ethylene-polyvinyl alcohol copolymer were put into an internal mixer and mixed at a mixing temperature of 70° C. and a mixing speed of 1500 r / min to obtain a mixture A;

[0050] S2, the mixture A, 180g of heavy calcium carbonate, 20g of tetrapod-shaped zinc oxide whiskers (the average length of the needles in the tetrapod-shaped zinc oxide whiskers is 200 microns), 50g of montmorillonite (calcium-based montmorillonite), 30g of stabilizer (N-cyclohexylmaleimide), 80g of plasticizer (epoxy fatty acid methyl ester), 2g of antioxidant (antioxidant 702) and 8g of lubricant (stearic acid) were mixed at a mixing temperature of 80°C and a mixing speed of 2500r / min, and the mixture was discharged to obtain a mixture B;

[0051] S3. Mixture B is kneaded and extruded at 180° C., and then pressed and molded in a hot press to obtain a cable material for use in seawater.

[0052] The EPDM rubber is EPDM, which was purchased from Dongguan Hongyi Plastic Technology Co., Ltd. under the trade name of Shanghai Sinopec Mitsui and model number 2032PM.

[0053] The ethylene content of the ethylene-polyvinyl alcohol copolymer was 30 mol% and the molecular weight was 10,000.

[0054] The difference between Example 2-3 and Example 1 is that the types, amounts and experimental parameters of the raw materials for preparing the cable materials used in seawater are different. The specific differences are shown in Table 1:

[0055] Table 1 Types, amounts and experimental parameters of raw materials for preparing cable materials for use in seawater in Examples 1-3

[0056]

[0057]

[0058] Example 4

[0059] A cable material for use in seawater. The difference between this embodiment and embodiment 1 is that the weight ratio of 380 g of polyvinyl chloride, 266 g of ethylene-polyvinyl alcohol copolymer and 76 g of ethylene propylene rubber is 40:28:8, and the types, amounts and experimental parameters of other raw materials are consistent with those in embodiment 1.

[0060] Example 5

[0061] A cable material for use in seawater. The difference between this embodiment and embodiment 1 is that the weight ratio of 380 g of polyvinyl chloride, 285 g of ethylene-polyvinyl alcohol copolymer and 76 g of ethylene propylene rubber is 40:30:8, and the types, amounts and experimental parameters of other raw materials are consistent with those in embodiment 1.

[0062] Example 6

[0063] A cable material for use in seawater. The difference between this embodiment and embodiment 1 is that the ethylene-propylene rubber is a modified ethylene-propylene rubber, and the modified ethylene-propylene rubber is prepared by the following method:

[0064] 50 g of ethylene-propylene rubber, 30 g of polyethylene and 5 g of initiator (isopropylbenzene peroxide) were mixed to obtain a mixture, and the mixture was added into an extruder at 150° C. and a pressure of 10 MPa, and extruded and granulated to obtain modified ethylene-propylene rubber.

[0065] The molecular weight of polyethylene is 10,000.

[0066] Example 7

[0067] A cable material for use in seawater. The difference between this embodiment and embodiment 2 is that the ethylene propylene rubber is a modified ethylene propylene rubber, and the modified ethylene propylene rubber is prepared by the following method:

[0068] 80 g of ethylene-propylene rubber, 40 g of polyethylene and 8 g of initiator (potassium persulfate) were mixed to obtain a mixture, and the mixture was added into an extruder at 180° C. and a pressure of 11 MPa, and extruded and granulated to obtain modified ethylene-propylene rubber.

[0069] The molecular weight of polyethylene is 5000.

[0070] Example 8

[0071] A cable material for use in seawater. The difference between this embodiment and embodiment 3 is that the ethylene-propylene rubber is a modified ethylene-propylene rubber, and the modified ethylene-propylene rubber is prepared by the following method:

[0072] 100 g of ethylene-propylene rubber, 50 g of polyethylene and 10 g of initiator (sodium bisulfite) were mixed to obtain a mixture, and the mixture was added into an extruder at 200° C. and a pressure of 12 MPa, and extruded and granulated to obtain modified ethylene-propylene rubber.

[0073] The molecular weight of polyethylene is 15,000.

[0074] Example 9

[0075] A cable material for use in seawater. The difference between this embodiment and embodiment 1 is that the stabilizer is obtained by mixing 13.6 g of N-cyclohexylmaleimide, 5.5 g of calcium-zinc composite stabilizer and 10.9 g of oxidized rare earth (cerium oxide) in a weight ratio of 5:2:4.

[0076] Example 10

[0077] A cable material for use in seawater. The difference between this embodiment and embodiment 6 is that the stabilizer is obtained by mixing 15.9 g of N-cyclohexylmaleimide, 3.5 g of calcium-zinc composite stabilizer and 10.6 g of oxidized rare earth (cerium oxide) in a weight ratio of 9:2:6.

[0078] Embodiment 11

[0079] A cable material for use in seawater. The difference between this embodiment and embodiment 9 is that calcium sebacate is used instead of an equal amount of N-cyclohexylmaleimide, and the other raw material types, amounts and experimental parameters are consistent with those in embodiment 1.

[0080] Example 12

[0081] A cable material for use in seawater. The difference between this embodiment and embodiment 9 is that calcium sebacate is used to replace an equal amount of calcium-zinc composite stabilizer, and the other raw material types, amounts and experimental parameters are consistent with those in embodiment 1.

[0082] Embodiment 13

[0083] A cable material for use in seawater. The difference between this embodiment and embodiment 9 is that calcium sebacate is used to replace an equal amount of oxidized rare earth, and the other raw material types, amounts and experimental parameters are consistent with those of embodiment 1.

[0084] Embodiment 14

[0085] A cable material for use in seawater. The difference between this embodiment and embodiment 1 is that the plasticizer is obtained by mixing 48 g of epoxy fatty acid methyl ester and 32 g of vinyl acetate in a weight ratio of 6:4.

[0086] Embodiment 15

[0087] A cable material for use in seawater. The difference between this embodiment and embodiment 6 is that the plasticizer is obtained by mixing 52.2 g of epoxy fatty acid methyl ester and 27.8 g of vinyl acetate in a weight ratio of 7.5:4.

[0088] Example 16

[0089] A cable material for use in seawater. The difference between this embodiment and embodiment 10 is that the plasticizer is obtained by mixing 55.4 epoxy fatty acid methyl ester and 24.6 vinyl acetate in a weight ratio of 9:4.

[0090] Embodiment 17

[0091] A cable material for use in seawater. The difference between this embodiment and embodiment 14 is that dibutyl sebacate is used instead of an equal amount of epoxy fatty acid methyl ester, and the other raw material types, amounts and experimental parameters are consistent with those in embodiment 1.

[0092] Embodiment 18

[0093] A cable material for use in seawater. The difference between this embodiment and embodiment 14 is that dibutyl sebacate is used instead of an equal amount of vinyl acetate, and the other raw material types, amounts and experimental parameters are consistent with those in embodiment 1.

[0094] Comparative Example

[0095] Comparative Example 1

[0096] A cable material for use in seawater. The difference between this embodiment and embodiment 1 is that polyethylene is used to replace an equal amount of ethylene-polyvinyl alcohol copolymer, and the other raw material types, amounts and experimental parameters are consistent with those in embodiment 1.

[0097] Polyethylene was purchased from Shanghai Oushuo Plastic Co., Ltd., model MVLDPE Thailand.

[0098] Comparative Example 2

[0099] A cable material for use in seawater. The difference between this embodiment and embodiment 1 is that nitrile rubber is used instead of an equal amount of EPDM rubber, and the other raw material types, amounts and experimental parameters are consistent with those in embodiment 1.

[0100] The nitrile rubber was purchased from Jining Fangyu Chemical Co., Ltd., model 1072CG.

[0101] Comparative Example 3

[0102] A cable material for use in seawater. The difference between this embodiment and embodiment 1 is that silicon dioxide is used to replace an equal amount of tetrapod-shaped zinc oxide whiskers, and the other raw material types, amounts and experimental parameters are consistent with those in embodiment 1.

[0103] Comparative Example 4

[0104] A cable material for use in seawater. The difference between this embodiment and embodiment 1 is that ceramic powder is used to replace an equal amount of montmorillonite, and the other raw material types, amounts and experimental parameters are consistent with those in embodiment 1.

[0105] Comparative Example 5

[0106] A cable material for use in seawater. The difference between this embodiment and embodiment 1 is that ceramic powder is used to replace an equal amount of heavy calcium carbonate, and the other raw material types, amounts and experimental parameters are consistent with those in embodiment 1.

[0107] Performance testing

[0108] The cable materials prepared in Examples 1-18 and Comparative Examples 1-5 were used to prepare cables for use in seawater, and the tensile strength, elongation at break, acid corrosion resistance, salt corrosion resistance, volume resistivity and low-temperature impact brittleness of the cables prepared for use in seawater were tested.

[0109] Detection method / test method

[0110] The detection of tensile strength and elongation at break refers to the standard GB / T 1701-2001. The corrosion treatment includes acid and salt treatment. The acid corrosion treatment is immersion in 10wt% hydrochloric acid at 60℃ for 150h, and the salt corrosion treatment is immersion in 30wt% saline at 60℃ for 150h. After cleaning and drying, the tensile strength is tested and the change rate compared with the initial tensile strength is calculated. The change rate (%) = (value after corrosion treatment / value without corrosion treatment) * 100%. The experimental data are shown in Table 2:

[0111] Table 2 Experimental data of Examples 1-18 and Comparative Examples 1-5

[0112]

[0113]

[0114] According to the PVC cable test standards specified in GB / 1410-2006 and GB / T5470-2008, the volume resistivity and low temperature impact brittleness test of the cable used in seawater were carried out. The experimental data are shown in Table 3:

[0115] Table 3 Experimental data of Examples 1-18 and Comparative Examples 1-5

[0116]

[0117]

[0118] From Examples 1-18 and Comparative Examples 1-5 in combination with Tables 2 and 3, it can be seen that the cable material prepared by the present application for use in seawater has good corrosion resistance, insulation, low temperature resistance, tensile strength and elongation at break.

[0119] Comparing Example 1 with Comparative Examples 1-2, the tensile strength and elongation at break of Comparative Examples 1-2 are both lower than those of Example 1; after acid corrosion and salt water corrosion, the change rates of tensile strength and elongation at break of Comparative Examples 1-2 are much lower than those of Example 1; the volume resistivity of Comparative Examples 1-2 is lower than that of Example 1, and cable breakage occurs in both low-temperature impact brittleness tests, indicating that the use of ethylene-propylene rubber, ethylene-vinyl alcohol copolymer and polyvinyl chloride in the present application is beneficial to improving the tensile strength, elongation at break, corrosion resistance, weather resistance, insulation and low-temperature resistance of the cable.

[0120] By comparing Example 1 with Comparative Examples 3-5, the tensile strength and elongation at break in Comparative Example 3-5 are not much different from those in the embodiment, but after acid corrosion and salt water corrosion, the change rate of tensile strength and the change rate of elongation at break in Comparative Example 3-5 are significantly lower than those in Example 1, and the volume resistivity in Comparative Example 3-5 is lower than that in Example 1, indicating that by using heavy calcium carbonate, tetrapod-shaped zinc oxide whiskers, montmorillonite and other raw materials together, the corrosion resistance, weather resistance and insulation of the cable can be effectively improved.

[0121] Compared with Example 1 and Example 4-5, the tensile strength and elongation at break of Example 4-5 are slightly improved, and after acid corrosion and salt water corrosion, the change rate of tensile strength and the change rate of elongation at break of Example 4-5 are also slightly improved, indicating that optimizing the usage ratio of polyvinyl chloride, ethylene propylene rubber and ethylene propylene rubber can make the overall performance of the cable better.

[0122] From Example 1 and Example 6, Example 2 and Example 7, Example 3 and Example 8, it can be clearly seen that the tensile strength and elongation at break of Examples 6-8 are improved, and after acid corrosion and salt water corrosion, the change rate of tensile strength and the change rate of elongation at break in Examples 6-8 are also improved, and the volume resistivity is also improved, indicating that the use of modified EPDM rubber can further improve the tensile strength, elongation at break, corrosion resistance, weather resistance and insulation of the cable.

[0123] Comparing Example 1 with Example 9, and Example 9 with Examples 11-13, the tensile strength and elongation at break in Example 9 are the best, and after acid corrosion and salt water corrosion, the changes in tensile strength and elongation at break in Example 9 are also the smallest, indicating that by mixing N-cyclohexylmaleimide, calcium zinc composite stabilizer and oxidized rare earth in a specific proportion, the tensile strength, elongation at break, corrosion resistance and weather resistance of the cable can be improved.

[0124] Compared with Example 1 and Example 14, and Example 14 and Examples 17-18, the tensile strength and elongation at break in Example 14 are the best, and after acid corrosion and salt water corrosion, the change in tensile strength and elongation at break in Example 14 is also the smallest, indicating that by mixing epoxy fatty acid methyl ester and vinyl acetate in a specific proportion, the tensile strength, elongation at break, corrosion resistance and weather resistance of the cable can be improved.

[0125] 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 cable material for use in seawater, characterized in that: Prepared from the following raw materials in parts by weight: 38-42 parts of polyvinyl chloride Ethylene-vinyl alcohol copolymer 25-30 parts 5-10 parts of EPDM Heavy calcium carbonate 18-23 parts 2-4 parts of tetrapod-shaped zinc oxide whiskers 5-7 parts of montmorillonite 3-6 parts of stabilizer Plasticizer 8-12 parts Antioxidant 0.2-0.5 parts Lubricant 0.8-1.2 parts.

2. The cable material for use in seawater according to claim 1, characterized in that: The weight ratio of the polyvinyl chloride, the ethylene-vinyl alcohol copolymer and the ethylene-propylene rubber is 40:(28-30):

8.

3. The cable material for use in seawater according to claim 1, characterized in that: The ethylene-propylene rubber is a modified ethylene-propylene rubber, and the modified ethylene-propylene rubber is prepared by the following method: According to weight parts, 5-10 parts by weight of ethylene-propylene rubber, 3-5 parts by weight of polyethylene and 0.5-1 parts by weight of initiator are mixed to obtain a mixture, and the mixture is added to an extruder at 150-200° C. and a pressure of 10-12 MPa, and extruded and granulated to obtain modified ethylene-propylene rubber.

4. The cable material for use in seawater according to claim 1, characterized in that: The stabilizer is obtained by mixing N-cyclohexylmaleimide, calcium zinc composite stabilizer and oxidized rare earth in a weight ratio of (5-9):2:(4-6).

5. The cable material for use in seawater according to claim 1, characterized in that: The plasticizer is obtained by mixing epoxy fatty acid methyl ester and vinyl acetate in a weight ratio of (6-9):

4.

6. The cable material for use in seawater according to claim 1, characterized in that: The content of ethylene in the ethylene-vinyl alcohol copolymer is 30-40 mol%.

7. The cable material for use in seawater according to claim 1, characterized in that: The average molecular weight of the polyvinyl chloride is 40,000-90,000.

8. The cable material for use in seawater according to claim 1, characterized in that: The average length of the needles in the four-needle zinc oxide whisker is 200-300 microns.

9. The cable material for use in seawater according to claim 1, characterized in that: The montmorillonite includes at least one of calcium-based montmorillonite, sodium-based montmorillonite and sodium-calcium-based montmorillonite.

10. A method for preparing a cable for use in seawater according to any one of claims 1 to 9, characterized in that: The method comprises the following preparation steps: S1, putting polyvinyl chloride, ethylene-propylene rubber and ethylene-vinyl alcohol copolymer into an internal mixer for mixing at a mixing temperature of 70-80° C. and a mixing speed of 1500-1800 r / min to obtain a mixture A; S2, mixing mixture A, heavy calcium carbonate, tetrapod-shaped zinc oxide whisker, montmorillonite, stabilizer, plasticizer, antioxidant and lubricant at a mixing temperature of 80-100° C. and a mixing speed of 2500-3000 r / min, discharging to obtain mixture B; S3. Mixture B is kneaded and extruded at 180-200° C., and then pressed and molded in a hot press to obtain a cable material for use in seawater.

Images