Anti-aging cable

Abstract

The invention relates to an anti-aging cable, and belongs to the technical field of cable preparation. The cable sleeve is prepared from the following raw materials: low-density polyethylene, modified alkali lignin, maleic anhydride, nano zinc oxide, 4, 4 '-thiobis (6-tert-butyl-3-methylphenol), tetra [beta-(3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid] pentaerythritol ester, phosphorus oxychloride, dicumyl peroxide, vinyl trimethoxy silane and dibutyl phthalate. According to the anti-aging cable sleeve disclosed by the invention, the nano zinc oxide, the 4, 4 '-thiobis (6-tert-butyl-3-methylphenol) and the tetra [beta-(3, 5-di-tert-butyl-4-hydroxyphenyl) propionic acid] pentaerythritol ester which are added have a synergistic effect, so that the prepared cable sleeve has an extremely good anti-aging effect; in addition, the modified alkali lignin is prepared, and zinc hypophosphite is added in the preparation process, so that the prepared cable has excellent flame retardant effect.

Description

Technical Field

[0001] The present invention belongs to the technical field of cable preparation, and in particular relates to an anti-aging cable. Background Art

[0002] With the gradual acceleration of urbanization and the increasing modernization of urban planning, wires and cables are an indispensable component of power transmission in urban construction. They connect various electrical devices and make power transmission more convenient and safe. However, over time and weather, cables are susceptible to the effects of ultraviolet rays, light, and heat, gradually aging and degrading, which reduces their transmission efficiency and service life. Currently, existing cables on the market do not effectively address these issues, making it particularly necessary to provide cables with excellent aging resistance. Summary of the Invention

[0003] The present invention aims to provide an aging-resistant cable. Nano zinc oxide, 4,4'-thiobis(6-tert-butyl-3-methylphenol) and pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] are added to the present invention. The synergistic effect of the three makes the prepared cable sheath have excellent aging resistance. In addition, the present invention prepares a modified alkali lignin, and zinc hypophosphite is added during the preparation process. The prepared alkali lignin is used as one of the raw materials for preparing the cable sheath, so that the prepared cable has excellent flame retardant effect. At the same time, maleic anhydride is added to improve the compatibility of the modified alkali lignin with low-density polyethylene, and phosphorus oxychloride is added as an acid source to effectively promote the cracking and condensation reaction of hydroxyl groups in the lignin, thereby catalyzing the formation of a carbon layer in the lignin, further consolidating the system, enhancing the flame retardancy of the system, and solving the problem of weak cable aging resistance existing in existing cable preparation technologies.

[0004] The purpose of the present invention can be achieved through the following technical solutions: An anti-aging cable comprises a cable core, wherein the outer circumference of the cable core is covered with a cable sheath, and the cable sheath comprises the following raw materials in parts by weight: 55-65 parts by weight of low-density polyethylene 0.1-0.5 parts by weight of modified alkali lignin 5-9 parts by weight of maleic anhydride 0.4-0.6 parts by weight of nano zinc oxide 4,4'-Thiobis(6-tert-butyl-3-methylphenol) 0.2-0.3 parts by weight 0.1-0.15 parts by weight of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate Phosphorus oxychloride 0.8-1.4 parts by weight 0.2-0.3 parts by weight of dicumyl peroxide 1-2 parts by weight of vinyltrimethoxysilane 2-3 parts by weight of dibutyl phthalate.

[0005] As a preferred embodiment of the present invention, the preparation method of the modified alkali lignin comprises the following steps: Alkali lignin, zinc hypophosphite, formaldehyde solution, sodium hydroxide and deionized water are evenly mixed and placed in the inner lining of a hydrothermal reactor, and then reacted at a controlled temperature. After the reaction is completed, the mixture is washed and filtered to obtain the alkali lignin to be dried. The alkali lignin to be dried is temperature-controlled and dried to obtain modified alkali lignin.

[0006] As a preferred embodiment of the present invention, the alkali lignin is 10-13 parts by weight, the zinc hypophosphite is 0.6-1 parts by weight, the formaldehyde solution is 5-6 parts by weight, the sodium hydroxide is 1-1.5 parts by weight and the deionized water is 9-15 parts by weight.

[0007] As a preferred embodiment of the present invention, the temperature of the temperature-controlled reaction is 100-110° C., and the time is 2-2.5 hours.

[0008] As a preferred embodiment of the present invention, the washing and filtering are specifically washing with deionized water and filtering 2-3 times.

[0009] As a preferred embodiment of the present invention, the temperature of the temperature-controlled drying is 80-90° C., and the degree of drying is drying to constant weight.

[0010] As a preferred embodiment of the present invention, the method for preparing the cable sheath comprises the following steps: S1. Mixing low-density polyethylene, dicumyl peroxide, phosphorus oxychloride, modified alkali lignin and maleic anhydride under temperature control to obtain blend A; S2. Add vinyltrimethoxysilane, dibutyl phthalate, nano zinc oxide, 4,4'-thiobis(6-tert-butyl-3-methylphenol) and pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] to blend A, and stir under controlled temperature to obtain blend B. S3. Extruding the blend B on the outer peripheral side of the cable core and cooling it to form a cable sheath, and at the same time preparing an anti-aging cable.

[0011] As a preferred solution of the present invention, the temperature for temperature-controlled mixing in step S1 is 80-100°C.

[0012] As a preferred embodiment of the present invention, the temperature of the temperature-controlled stirring in step S2 is 170-185° C. and the time is 20-30 minutes.

[0013] Beneficial effects of the present invention: (1) The present invention adds nano zinc oxide, 4,4'-thiobis(6-tert-butyl-3-methylphenol) and pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate], so that the prepared cable sheath has excellent anti-aging effect. This is because when the cable sheath participates in the antioxidant effect, the hydroxyl groups in 4,4'-thiobis(6-tert-butyl-3-methylphenol) will react with the peroxyl radicals in the system to generate hydroperoxides, and the sulfur atoms can decompose the hydroperoxides into alcohols, thereby stabilizing the polymer; on this basis, the present invention is supplemented with pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate], so that the hydroxyl groups and ester groups in the tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] react chemically with oxygen molecules to reduce the oxidative damage of oxygen to the cable; at the same time, the present invention also adds nano zinc oxide to capture free radicals, thereby destroying the free radical chain reaction, so that the system has excellent ultraviolet shielding effect and antioxidant effect. That is, the synergistic effect between the three in the system makes the prepared cable sheath have excellent anti-aging effect.

[0014] (2) The present invention prepares a modified alkali lignin, and zinc hypophosphite is added during the preparation process. The prepared alkali lignin is used as one of the raw materials for preparing cable sheaths, so that the prepared cable has excellent flame retardant effect. This is because the phosphorus element introduced into the alkali lignin will generate phosphoric acid or polyphosphoric acid when the cable is heated and burned, which can promote the dehydration and carbonization reaction of the lignin to form a continuous carbon layer. The formation of the carbon layer inhibits the leakage of volatiles, isolates oxygen, and delays the spread of flames, thereby achieving a flame retardant effect. At the same time, in this system, the alkali lignin has been hydroxymethylated to change its molecular structure. This change improves the pyrolysis characteristics of the lignin, reduces the pyrolysis reaction inside the carbon layer, reduces the release of pyrolysis products, and enhances the stability of the carbon layer.

[0015] (3) The present invention adds maleic anhydride to improve the compatibility of modified alkali lignin with low-density polyethylene, further enhancing the flame retardancy of the system. This is because after the reaction between maleic anhydride and low-density polyethylene, polar groups will appear on the low-density polyethylene molecular chain. These polar groups increase the mutual adsorption capacity between the low-density polyethylene molecular chain and lignin, promote the interaction between the two, and further increase the compatibility of lignin and low-density polyethylene.

[0016] (4) The present invention adds phosphorus oxychloride as an acid source, which effectively promotes the cracking and condensation reaction of the hydroxyl groups in the lignin, and then catalyzes the lignin to form a carbon layer, further consolidating the system and enhancing the flame retardancy of the system. DETAILED DESCRIPTION

[0017] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0018] Example 1 A modified alkali lignin, wherein the preparation method of the modified alkali lignin comprises the following steps: 10 parts by weight of alkali lignin, 0.8 parts by weight of zinc hypophosphite, 5 parts by weight of formaldehyde solution, 1.5 parts by weight of sodium hydroxide and 9 parts by weight of deionized water were mixed evenly and placed in the inner lining of a hydrothermal reactor, and then the temperature was controlled at 100° C. to react for 2 hours. After the reaction was completed, it was washed with deionized water and filtered twice to obtain the alkali lignin to be dried. The alkali lignin to be dried was controlled at 90° C. and dried to constant weight to obtain modified alkali lignin.

[0019] Example 2 A modified alkali lignin, wherein the preparation method of the modified alkali lignin comprises the following steps: 13 parts by weight of alkali lignin, 0.6 parts by weight of zinc hypophosphite, 5.5 parts by weight of formaldehyde solution, 1 part by weight of sodium hydroxide and 15 parts by weight of deionized water were mixed evenly and placed in the inner lining of a hydrothermal reactor, and then the temperature was controlled at 105°C for reaction for 2.3 hours. After the reaction was completed, it was washed with deionized water and filtered three times to obtain the alkali lignin to be dried. The alkali lignin to be dried was controlled at 80°C and dried to constant weight to obtain modified alkali lignin.

[0020] Example 3 A modified alkali lignin, wherein the preparation method of the modified alkali lignin comprises the following steps: 11 parts by weight of alkali lignin, 1 part by weight of zinc hypophosphite, 6 parts by weight of formaldehyde solution, 1.3 parts by weight of sodium hydroxide and 12 parts by weight of deionized water were mixed evenly and placed in the inner lining of a hydrothermal reactor, and then the temperature was controlled at 110°C for reaction for 2.5 hours. After the reaction was completed, it was washed with deionized water and filtered twice to obtain the alkali lignin to be dried. The alkali lignin to be dried was controlled at 85°C and dried to constant weight to obtain modified alkali lignin.

[0021] Comparative Example 1 Compared with Example 2, the difference of Comparative Example 1 is that zinc hypophosphite is not added, and the other preparation steps and parameters are the same.

[0022] Example 4 An anti-aging cable comprises a cable core, wherein the outer circumference of the cable core is covered with a cable sheath, and the cable sheath comprises the following raw materials in parts by weight: 60 parts by weight of low-density polyethylene 0.1 parts by weight of modified alkali lignin prepared in Example 1 9 parts by weight of maleic anhydride 0.4 parts by weight of nano zinc oxide 4,4'-Thiobis(6-tert-butyl-3-methylphenol) 0.25 parts by weight 0.13 parts by weight of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate 0.8 parts by weight of phosphorus oxychloride 0.2 parts by weight of dicumyl peroxide 1 part by weight of vinyltrimethoxysilane 3 parts by weight of dibutyl phthalate.

[0023] The preparation method of the cable cover comprises the following steps: S1. Low-density polyethylene, dicumyl peroxide, phosphorus oxychloride, the modified alkali lignin prepared in Example 1, and maleic anhydride were mixed uniformly at a temperature of 80° C. to obtain a blend A; S2. Add vinyltrimethoxysilane, dibutyl phthalate, nano zinc oxide, 4,4'-thiobis(6-tert-butyl-3-methylphenol) and pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] to blend A, and stir at 185°C for 25 minutes to obtain blend B. S3. Extruding the blend B on the outer peripheral side of the cable core and cooling it to form a cable sheath, and at the same time preparing an anti-aging cable.

[0024] Example 5 An anti-aging cable comprises a cable core, wherein the outer circumference of the cable core is covered with a cable sheath, and the cable sheath comprises the following raw materials in parts by weight: 65 parts by weight of low-density polyethylene 0.3 parts by weight of modified alkali lignin prepared in Example 3 5 parts by weight of maleic anhydride 0.5 parts by weight of nano zinc oxide 0.3 parts by weight of 4,4'-thiobis(6-tert-butyl-3-methylphenol) 0.15 parts by weight of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate 1.4 parts by weight of phosphorus oxychloride 0.3 parts by weight of dicumyl peroxide 1.5 parts by weight of vinyltrimethoxysilane 2 parts by weight of dibutyl phthalate.

[0025] The preparation method of the cable cover comprises the following steps: S1. Low-density polyethylene, dicumyl peroxide, phosphorus oxychloride, the modified alkali lignin prepared in Example 3, and maleic anhydride were mixed uniformly at a temperature of 100° C. to obtain a blend A; S2. Add vinyltrimethoxysilane, dibutyl phthalate, nano zinc oxide, 4,4'-thiobis(6-tert-butyl-3-methylphenol) and pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] to blend A, and stir at 170°C for 30 minutes to obtain blend B. S3. Extruding the blend B on the outer peripheral side of the cable core and cooling it to form a cable sheath, and at the same time preparing an anti-aging cable.

[0026] Example 6 An anti-aging cable comprises a cable core, wherein the outer circumference of the cable core is covered with a cable sheath, and the cable sheath comprises the following raw materials in parts by weight: 55 parts by weight of low-density polyethylene 0.5 parts by weight of modified alkali lignin prepared in Example 2 7 parts by weight of maleic anhydride 0.6 parts by weight of nano zinc oxide 0.2 parts by weight of 4,4'-thiobis(6-tert-butyl-3-methylphenol) 0.1 parts by weight of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate 1.1 parts by weight of phosphorus oxychloride 0.2 parts by weight of dicumyl peroxide 2 parts by weight of vinyltrimethoxysilane 2.5 parts by weight of dibutyl phthalate.

[0027] The preparation method of the cable cover comprises the following steps: S1. Low-density polyethylene, dicumyl peroxide, phosphorus oxychloride, the modified alkali lignin prepared in Example 2, and maleic anhydride were mixed uniformly at a temperature of 90° C. to obtain a blend A; S2. Add vinyltrimethoxysilane, dibutyl phthalate, nano zinc oxide, 4,4'-thiobis(6-tert-butyl-3-methylphenol) and pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] to blend A, and stir at 178°C for 20 minutes to obtain blend B. S3. Extruding the blend B on the outer peripheral side of the cable core and cooling it to form a cable sheath, and at the same time preparing an anti-aging cable.

[0028] Comparative Example 2 Compared with Example 6, the difference of Comparative Example 2 is that the modified alkali lignin prepared in Example 2 is replaced by the modified alkali lignin prepared in Comparative Example 1, and the other preparation steps and parameters are the same.

[0029] Comparative Example 3 Compared with Example 6, the difference of Comparative Example 3 is that no modified alkali lignin is added, and the other preparation steps and parameters are the same.

[0030] Comparative Example 4 Compared with Example 6, the difference of Comparative Example 4 is that no maleic anhydride is added, and the remaining preparation steps and parameters are the same.

[0031] Comparative Example 5 Compared with Example 6, the difference of Comparative Example 5 is that phosphorus oxychloride is not added, and the remaining preparation steps and parameters are the same.

[0032] Comparative Examples 6-8 Compared with Example 6, the difference between Comparative Examples 6-8 is that the weight proportions of nano zinc oxide, 4,4'-thiobis(6-tert-butyl-3-methylphenol) and pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] are as shown in Table 1, and the remaining preparation steps and parameters are the same.

[0033] Table 1 Test Case (1) The cables prepared in Examples 4-6 and Comparative Examples 2-5 were subjected to oxygen index tests according to GB / T 2406-1993. The results are shown in Table 2.

[0034] (2) The blend B obtained in step S2 of Examples 4-6 and Comparative Examples 6-8 was molded into dumbbell-shaped strips of type 5B. The cut strips were then conditioned at a temperature of 25°C and a relative humidity of 65% for 16 h. Mechanical properties tests were performed on a universal material testing machine at a test speed of 10 mm / min. Tensile strength tests were performed according to GB / T 1040-2006. UV aging tests were performed according to GB / T 16422.3-2014. The results are shown in Table 2.

[0035] Table 2 As can be seen from Examples 4-6 and Comparative Examples 2-3 in Table 2, the cables produced by the present invention exhibit excellent flame retardancy. This is because the present invention prepares a modified alkali lignin, adds zinc hypophosphite during the preparation process, and uses the resulting alkali lignin as one of the raw materials for preparing the cable sheath. The phosphorus introduced into the alkali lignin generates phosphoric acid or polyphosphoric acid when the cable is heated and burned. These phosphoric acid and polyphosphoric acid promote the dehydration and carbonization of the lignin, forming a continuous char layer. The formation of the char layer inhibits the leakage of volatiles, isolates oxygen, and slows the spread of flames, thereby achieving a flame retardant effect. The present invention adds maleic anhydride. After the maleic anhydride reacts with low-density polyethylene, polar groups will be present on the low-density polyethylene molecular chain. These polar groups increase the mutual adsorption capacity of the low-density polyethylene molecular chain and lignin, promote the interaction between the two, further increase the compatibility of lignin and low-density polyethylene, and further enhance the flame retardancy of the system. The present invention adds phosphorus oxychloride as an acid source, which can effectively promote the cracking and condensation reactions of hydroxyl groups in lignin, and then catalyze the lignin to form a carbon layer, further consolidating the system and enhancing the flame retardancy of the system.

[0036] As shown in Examples 4-6 and Comparative Examples 6-8 in Table 2, the cable sheaths produced by the present invention exhibit excellent anti-aging properties. This is because, when the cable sheath participates in the antioxidant effect, the hydroxyl groups in 4,4'-thiobis(6-tert-butyl-3-methylphenol) react with peroxyl radicals in the system to form hydroperoxides, and the sulfur atoms decompose the hydroperoxides into alcohols, thereby stabilizing the polymer. Furthermore, the addition of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] allows the hydroxyl and ester groups in the sheath to react chemically with oxygen molecules, reducing oxygen oxidative damage to the cable. Furthermore, the present invention also incorporates nano-zinc oxide to capture free radicals, thereby disrupting free radical chain reactions. This results in the system possessing both excellent UV shielding and antioxidant properties. The synergistic effect of these three components in the system gives the resulting cable sheath excellent anti-aging properties.

[0037] Throughout the specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0038] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the described specific embodiments or replace them in similar ways. As long as they do not deviate from the invention or exceed the scope defined by the claims, they should all fall within the scope of protection of the present invention.

Claims

1. An anti-aging cable, comprising a cable core, characterized in that: The outer peripheral side of the cable core is covered with a cable sleeve, and the cable sleeve comprises the following raw materials in parts by weight: 55-65 parts by weight of low-density polyethylene 0.1-0.5 parts by weight of modified alkali lignin 5-9 parts by weight of maleic anhydride 0.4-0.6 parts by weight of nano zinc oxide 4,4'-Thiobis(6-tert-butyl-3-methylphenol) 0.2-0.3 parts by weight 0.1-0.15 parts by weight of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate Phosphorus oxychloride 0.8-1.4 parts by weight 0.2-0.3 parts by weight of dicumyl peroxide 1-2 parts by weight of vinyltrimethoxysilane 2-3 parts by weight of dibutyl phthalate.

2. The anti-aging cable according to claim 1, characterized in that: The preparation method of the modified alkali lignin comprises the following steps: Alkali lignin, zinc hypophosphite, formaldehyde solution, sodium hydroxide and deionized water are evenly mixed and placed in the inner lining of a hydrothermal reactor, and then reacted at a controlled temperature. After the reaction is completed, the mixture is washed and filtered to obtain the alkali lignin to be dried. The alkali lignin to be dried is temperature-controlled and dried to obtain modified alkali lignin.

3. The anti-aging cable according to claim 2, characterized in that: The alkali lignin is 10-13 parts by weight, the zinc hypophosphite is 0.6-1 parts by weight, the formaldehyde solution is 5-6 parts by weight, the sodium hydroxide is 1-1.5 parts by weight and the deionized water is 9-15 parts by weight.

4. The anti-aging cable according to claim 2, characterized in that: The temperature of the temperature-controlled reaction is 100-110° C., and the time is 2-2.5 hours.

5. The anti-aging cable according to claim 2, characterized in that: The washing and filtering specifically includes washing with deionized water and filtering 2-3 times.

6. The anti-aging cable according to claim 2, characterized in that: The temperature of the temperature-controlled drying is 80-90° C., and the degree of drying is drying to constant weight.

7. The anti-aging cable according to claim 1, characterized in that: The preparation method of the cable cover comprises the following steps: S1. Mixing low-density polyethylene, dicumyl peroxide, phosphorus oxychloride, modified alkali lignin and maleic anhydride under temperature control to obtain blend A; S2. Add vinyltrimethoxysilane, dibutyl phthalate, nano zinc oxide, 4,4'-thiobis(6-tert-butyl-3-methylphenol) and pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] to blend A, and stir under controlled temperature to obtain blend B. S3. Extruding the blend B on the outer peripheral side of the cable core and cooling it to form a cable sheath, and at the same time preparing an anti-aging cable.

8. The anti-aging cable according to claim 7, characterized in that: The temperature for temperature-controlled mixing in step S1 is 80-100°C.

9. The anti-aging cable according to claim 7, characterized in that: The temperature of the temperature-controlled stirring in step S2 is 170-185° C. and the time is 20-30 minutes.

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