Cold-resistant and anti-freezing cable and preparation method thereof

Abstract

The invention discloses a cold-resistant and anti-freezing cable and a preparation method thereof, and relates to the technical field of cables. The cold-resistant and anti-freezing cable sequentially comprises a sheath layer, an insulating layer and a conductive core layer from outside to inside, the sheath layer is prepared from a sheath material, and the sheath material comprises polyvinyl chloride resin, dioctyl terephthalate, modified polyurethane, epoxidized soybean oil, aluminum hydroxide, magnesium hydroxide, a calcium-zinc stabilizer and modified halloysite. The sheath material prepared by the invention has good mechanical properties, antibacterial properties and anti-aging properties, and is suitable for cold-resistant and anti-freezing cables.

Description

Technical Field

[0001] The present invention relates to the technical field of cables, and specifically to a cold-resistant and freeze-resistant cable and its preparation method. Background Art

[0002] As an indispensable component in power transmission and distribution, the structural design and material selection of cables are both crucial. A cable mainly consists of the following key parts: a conductor, an insulating layer, a sheath layer, etc.

[0003] Among them, the sheath layer is an important protective structure on the outer layer of the cable. Its main functions are to prevent water, fire resistance, corrosion resistance, and withstand external mechanical forces. There are various material choices for the sheath layer, and common ones include polyvinyl chloride, polyethylene, chlorinated polyethylene, etc.; Polyvinyl chloride materials have good flexibility and firmness, and also have characteristics such as fire prevention and oil resistance. However, they contain substances harmful to the environment and the human body, have limitations in special environment applications, and generally have poor weather resistance and are not very suitable for high-temperature environments. Polyethylene materials have excellent electrical insulation performance, processing performance, and high-temperature anti-deformation ability, and are more environmentally friendly than polyvinyl chloride, but have poor hardness.

[0004] In view of the possible disadvantages of the sheath layer materials, such as low hardness, poor cold resistance, and poor toughness, the following measures can be taken for improvement: First, it can be solved by replacing the material. For example, for scenarios that require higher flexibility and cold resistance, materials such as polyurethane can be selected. Secondly, it can be considered to add reinforcing agents or modifiers to the sheath layer to improve its performance, such as adding nanomaterials to enhance hardness and wear resistance, or adding cross-linking agents to improve its cold resistance and stability; In addition, endowing the sheath layer material with other functions can also extend the durability of the cable. For example, when the cable is used outdoors for a long time, endowing the cable with anti-ultraviolet aging performance can delay the aging of the cable material.

[0005] In summary, there are various material choices for the sheath layer of the cable, each with its own advantages and disadvantages. In practical applications, it is necessary to select appropriate materials according to the specific usage environment and requirements, and improve its performance by optimizing the production process and adding modifiers, etc. Summary of the Invention

[0006] The purpose of the present invention is to provide a cold-resistant and freeze-resistant cable and its preparation method to solve the problems existing in the prior art.

[0007] To solve the above technical problems, the present invention provides the following technical solutions:

[0008] A cold-resistant and freeze-resistant cable, the cold-resistant and freeze-resistant cable sequentially includes a sheath layer, an insulating layer, and a conductive core layer from outside to inside; the sheath layer is made of a sheath layer material;

[0009] Preferably, the preparation method of the sheath layer material comprises the following preparation steps:

[0010] (1) Under anhydrous and anaerobic conditions, m-tetra(4-pyridyl)porphyrin and 4-chloromethylphenylboronic acid are weighed at a molar ratio of 1:(4.1 - 4.2). m-tetra(4-pyridyl)porphyrin and chloroform are mixed at a mass ratio of 1:(10 - 12), heated to 65 - 70 °C, 4-chloromethylphenylboronic acid is added, and the reaction is carried out for 72 h. After the reaction is completed, filtration is carried out, followed by column chromatography, elution with a first eluent and a second eluent, the second eluent is collected, and the product eluted with the second eluent is concentrated and vacuum dried to obtain modified porphyrin;

[0011] (2) Poly(tetrahydrofuran)ether diol, dicyclohexylmethane-4,4'-diisocyanate, and 4-aminophenylboronic acid are weighed at a molar ratio of 5:10:12. Poly(tetrahydrofuran)ether diol and dimethylacetamide are mixed at a mass ratio of 1:(3 - 4), heated to 60 °C, dicyclohexylmethane-4,4'-diisocyanate and dibutyltin dilaurate with a volume 0.003 - 0.005 times that of dimethylacetamide are added, and the reaction is carried out for 4 h under nitrogen protection. 4-aminophenylboronic acid is added, and the reaction is continued for 8 h. After the reaction is completed, filtration is carried out and washed with pure water 3 - 4 times, and then vacuum dried to obtain modified polyurethane;

[0012] (3) Silane coupling agent modified halloysite, 3-allyl-2-hydroxybenzaldehyde, perfluorobutylethylene, azobisisobutyronitrile, and chloroform are mixed at a mass ratio of 1:(0.03 - 0.04):(0.03 - 0.05):0.01:(40 - 50), heated to 65 - 70 °C and refluxed for 6 - 8 h. After the reaction is completed, filtration is carried out and washed with anhydrous ethanol 3 - 4 times, and dried at 80 °C for 24 h to obtain pre-modified halloysite;

[0013] (4) Iodine, tert-butyl hydroperoxide, potassium carbonate, and 2-hydrazino-5-bromopyridine are weighed at a molar ratio of 0.2:2:1:1. Pre-modified halloysite, 2-hydrazino-5-bromopyridine, and 1,4-dioxane are mixed at a mass ratio of 1:(0.04 - 0.05):(40 - 50), iodine, tert-butyl hydroperoxide, and potassium carbonate are added, and the temperature is raised to 80 °C for reaction for 1 - 2 h. After the reaction is completed, filtration is carried out and washed with saturated sodium thiosulfate solution 2 - 3 times, and then washed with pure water 3 - 4 times, and dried at 80 °C for 24 h to obtain modified halloysite;

[0014] (5) Weigh the following raw materials by mass parts: 100 parts of polyvinyl chloride resin, 5 - 7 parts of modified porphyrin, 15 parts of dioctyl terephthalate, 15 - 25 parts of modified polyurethane, 5 parts of epoxy soybean oil, 10 parts of aluminum hydroxide, 5 parts of magnesium hydroxide, 5 parts of calcium zinc stabilizer, 10 parts of calcium chloride, 5 - 7 parts of modified halloysite. Dry the above raw materials in a vacuum drying oven at 60 °C for 12 h, then carry out mixing in a kneader. After the mixing is completed, discharge the material and send it into a twin-screw extruder for extrusion molding; after extrusion, carry out compression molding under the action of a flat vulcanizing machine to obtain the sheath layer material.

[0015] Preferably, the chromatography column used in step (1) for column chromatography is a silica gel chloroform column; the first eluent is obtained by mixing chloroform and methanol in a mass ratio of 10:1; the second eluent is obtained by mixing chloroform and methanol in a mass ratio of 5:1.

[0016] Preferably, the preparation method of the silane coupling agent modified halloysite in step (3) is: mix halloysite and a 4 mol / L sodium hydroxide solution in a mass ratio of 1:40, stir at 80 °C for 3 h. After stirring is completed, filter and wash with pure water 6 times, dry at 80 °C for 24 h, grind through a 200-mesh sieve. Mix the sieved halloysite and the silane coupling agent solution in a mass ratio of 1:40, ultrasonicate for 10 min, then react at 60 °C for 4 h. After reacting for 4 h, filter and wash with pure water 6 times, dry at 80 °C for 24 h to obtain the silane coupling agent modified halloysite.

[0017] Preferably, the temperature of the kneader in step (5) is 100 - 120 °C, the time is 20 - 30 min, the rotation speed is 100 - 200 rpm, the vulcanization temperature of the flat vulcanizing machine is 160 - 170 °C, the pressure is 10 MPa, and the time is 12 min.

[0018] Preferably, the polyvinyl chloride resin grade in step (5) is S-70; the model of the calcium zinc stabilizer is 9876.

[0019] Preferably, the preparation method of the silane coupling agent solution is: use a 90 wt% ethanol solution as the solvent, and prepare a 2 wt% solution of vinyltrimethoxysilane to obtain the silane coupling agent solution.

[0020] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0021] The cold-resistant and freeze-resistant cable of the present invention sequentially includes a sheath layer, an insulating layer, and a conductive core layer from outside to inside; the sheath layer is prepared from a sheath material. When preparing the sheath material in the present invention, first, 4-chloromethylphenylboronic acid and meso-tetrakis(4-pyridyl)porphyrin are reacted to obtain modified porphyrin; chloromethyl and pyridine react to generate pyridine quaternary ammonium salt with antibacterial properties, and a phenylboronic acid structure is grafted onto meso-tetrakis(4-pyridyl)porphyrin; polytetrahydrofuran ether diol, dicyclohexylmethane-4,4'-diisocyanate, and 4-aminophenylboronic acid are reacted to obtain modified polyurethane, so that the modified polyurethane is grafted with a phenylboronic acid structure; the modified polyurethane has good elasticity and can toughen the sheath material.

[0022] First, 4-chloromethylphenylboronic acid and meso-tetrakis(4-pyridyl)porphyrin are reacted to obtain modified porphyrin; chloromethyl and pyridine react to generate pyridine quaternary ammonium salt with antibacterial properties, and a phenylboronic acid structure is grafted onto meso-tetrakis(4-pyridyl)porphyrin; polytetrahydrofuran ether diol, dicyclohexylmethane-4,4'-diisocyanate, and 4-aminophenylboronic acid are reacted to obtain modified polyurethane, so that the modified polyurethane is grafted with a phenylboronic acid structure; the modified polyurethane has good elasticity and can toughen the sheath material.

[0023] Secondly, 3-allyl-2-hydroxybenzaldehyde and perfluorobutylethylene are polymerized on the surface of halloysite treated with vinyltrimethoxysilane to obtain pre-modified halloysite; a large number of double bonds are contained on the surface of halloysite treated with vinyltrimethoxysilane, and 3-allyl-2-hydroxybenzaldehyde and perfluorobutylethylene can be initiated to polymerize on its surface under the action of an initiator, so that a fluorine element with low surface energy and a hydroxybenzaldehyde structure are grafted onto the surface of halloysite; halloysite, as an inorganic filler, can enhance the mechanical properties of the sheath material, and the fluorine element with low surface energy can improve the weather resistance of the sheath material and provide hydrophobic properties; the pre-modified halloysite and 2-hydrazino-5-bromopyridine are reacted to obtain modified halloysite, and the aldehyde group on the hydroxybenzaldehyde structure of the pre-modified halloysite and the hydrazino group on 2-hydrazino-5-bromopyridine generate a triazole structure through nucleophilic addition, nucleophilic substitution, and dehydrogenation aromatization. The triazole structure has good antibacterial properties, and the triazole structure and the hydroxy group on hydroxybenzaldehyde generate an intramolecular chelate ring, which can convert light energy into heat energy, thereby improving the anti-aging performance of the sheath material.

[0024] Finally, polyvinyl chloride resin, modified porphyrin, dioctyl terephthalate, modified polyurethane, epoxy soybean oil, aluminum hydroxide, magnesium hydroxide, calcium-zinc stabilizer, and modified halloysite are kneaded and extruded, and then vulcanized by a flat vulcanizer to obtain a sheath material; during the high-temperature kneading process, the phenylboronic acid structure on the modified polyurethane can not only crosslink with the phenylboronic acid on the modified porphyrin, but also undergo self-crosslinking to form a dense crosslinked network, thereby improving the mechanical properties of the sheath material; aluminum hydroxide and magnesium hydroxide are common additive materials in the sheath material; the modified porphyrin can complex with aluminum and magnesium to form metal porphyrin, and the metal porphyrin has good photocatalytic effect and can effectively degrade the surface pollutants of the sheath material; bromine is introduced when the pre-modified halloysite reacts with 2-hydrazino-5-bromopyridine, and bromine and pyridine can regenerate pyridinium quaternary salt during the high-temperature kneading process, increasing the crosslinked network and further improving the antibacterial performance. Detailed implementation mode

[0025] Next, in combination with the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

[0026] The materials used in the following examples and comparative examples are as follows:

[0027] Polyvinyl chloride resin, grade S-70, purchased from Formosa Plastics Corporation, Taiwan, China;

[0028] Aluminum hydroxide, density 2.4 - 2.8 g / cm 3 , purchased from Jiangsu Aiteke Flame Retardant Materials Co., Ltd., China;

[0029] Magnesium hydroxide, density 2.4 - 2.8 g / cm 3 , purchased from Aluminum Corporation of China;

[0030] Epoxy soybean oil, density 0.989 g / cm 3 , refractive index 1.473, purchased from Qilu Petrochemical, China;

[0031] Calcium-zinc stabilizer, model 9876, purchased from German Xiong Brand;

[0032] The chromatography column used for column chromatography is a silica gel chloroform column; the first eluent is a mixture of chloroform and methanol in a mass ratio of 10:1; the second eluent is a mixture of chloroform and methanol in a mass ratio of 5:1.

[0033] Example 1:

[0034] A cold-resistant and freeze-resistant cable, which sequentially includes a sheath layer, an insulating layer, and a conductive core layer from outside to inside. The sheath layer is made of a sheath material, and the preparation method of the sheath material is as follows:

[0035] (1) Under anhydrous and anaerobic conditions, weigh meso-tetrakis(4-pyridyl)porphyrin and 4-chloromethylphenylboronic acid according to a molar ratio of 1:4.1. Mix meso-tetrakis(4-pyridyl)porphyrin and chloroform according to a mass ratio of 1:10, heat up to 70 °C, add 4-chloromethylphenylboronic acid and react for 72 h. After the reaction is completed, filter and perform column chromatography, elute with a first eluent and a second eluent, collect the second eluent, and concentrate and vacuum-dry the eluate of the second eluent to obtain modified porphyrin;

[0036] (2) Weigh polytetrahydrofuran ether glycol, dicyclohexylmethane-4,4'-diisocyanate, and 4-aminophenylboronic acid according to a molar ratio of 5:10:12. Mix polytetrahydrofuran ether glycol and dimethylacetamide according to a mass ratio of 1:3, heat to 60 °C, add dicyclohexylmethane-4,4'-diisocyanate and dibutyltin dilaurate with a volume 0.003 times that of dimethylacetamide, react for 4 h under nitrogen protection, add 4-aminophenylboronic acid, and continue to react for 8 h. After the reaction is completed, filter and wash 4 times with pure water, and vacuum-dry to obtain modified polyurethane;

[0037] (3) Use a 90 wt% ethanol solution as a solvent, and prepare a 2 wt% solution of vinyltrimethoxysilane to obtain a silane coupling agent solution; mix halloysite and a 4 mol / L sodium hydroxide solution according to a mass ratio of 1:40, stir at 80 °C for 3 h. After stirring is completed, filter and wash 6 times with pure water, dry at 80 °C for 24 h, grind through a 200-mesh sieve. Mix the sieved halloysite and the silane coupling agent solution according to a mass ratio of 1:40, ultrasonicate for 10 min, and react at 60 °C for 4 h. After reacting for 4 h, filter and wash 6 times with pure water, and dry at 80 °C for 24 h to obtain silane coupling agent-modified halloysite; mix the silane coupling agent-modified halloysite, 3-allyl-2-hydroxybenzaldehyde, perfluorobutylethylene, azobisisobutyronitrile, and chloroform according to a mass ratio of 1:0.03:0.03:0.01:40, heat up to 70 °C and reflux for 8 h. After the reaction is completed, filter and wash 4 times with absolute ethanol, and dry at 80 °C for 24 h to obtain pre-modified halloysite;

[0038] (4) Weigh iodine, tert-butyl hydroperoxide, potassium carbonate, and 2-hydrazinyl-5-bromopyridine according to a molar ratio of 0.2:2:1:1. Mix pre-modified halloysite, 2-hydrazinyl-5-bromopyridine, and 1,4-dioxane according to a mass ratio of 1:0.04:40. Add iodine, tert-butyl hydroperoxide, and potassium carbonate, and heat up to 80 °C for reaction for 2 h. After the reaction is completed, filter and wash with saturated sodium thiosulfate solution three times, then wash with pure water four times, and dry at 80 °C for 24 h to obtain modified halloysite;

[0039] (5) Weigh the following raw materials according to the number of mass parts: 100 parts of polyvinyl chloride resin, 5 parts of modified porphyrin, 15 parts of dioctyl terephthalate, 15 parts of modified polyurethane, 5 parts of epoxy soybean oil, 10 parts of aluminum hydroxide, 5 parts of magnesium hydroxide, 5 parts of calcium-zinc stabilizer, 10 parts of calcium chloride, and 5 parts of modified halloysite. Dry the above raw materials in a vacuum drying oven at 60 °C for 12 h, then carry out mixing in a mixer. After the mixing is completed, discharge the material and send it into a twin-screw extrusion granulator for extrusion molding; after extrusion, carry out compression molding under the action of a flat vulcanizing machine to obtain the sheath layer material; the temperature of the mixer is 120 °C, the time is 30 min, the rotation speed is 200 rpm, the vulcanization temperature of the flat vulcanizing machine is 170 °C, the pressure is 10 MPa, and the time is 12 min.

[0040] Example 2:

[0041] A cold-resistant and freeze-resistant cable, and the preparation method of the sheath material thereof comprises the following preparation steps:

[0042] (1) Under anhydrous and anaerobic conditions, weigh meso-tetra(4-pyridyl)porphyrin and 4-chloromethylphenylboronic acid according to a molar ratio of 1:4.1. Mix meso-tetra(4-pyridyl)porphyrin and chloroform according to a mass ratio of 1:11, heat up to 67 °C, add 4-chloromethylphenylboronic acid and react for 72 h. After the reaction is completed, filter and carry out column chromatography, elute with the first eluent and the second eluent, collect the second eluent, and concentrate and vacuum dry the elution product of the second eluent to obtain modified porphyrin;

[0043] (2) Weigh polytetrahydrofuran ether glycol, dicyclohexylmethane-4,4'-diisocyanate, and 4-aminophenylboronic acid according to a molar ratio of 5:10:12. Mix polytetrahydrofuran ether glycol and dimethylacetamide according to a mass ratio of 1:3.5, heat up to 60 °C, add dicyclohexylmethane-4,4'-diisocyanate and dibutyltin dilaurate which is 0.004 times the volume of dimethylacetamide, react under nitrogen protection for 4 h, add 4-aminophenylboronic acid, and continue to react for 8 h. After the reaction is completed, filter and wash with pure water three times, and carry out vacuum drying to obtain modified polyurethane;

[0044] (3) Using a 90 wt% ethanol solution as a solvent, vinyltrimethoxysilane was formulated into a 2 wt% solution to obtain a silane coupling agent solution; halloysite and a 4 mol / L sodium hydroxide solution were mixed at a mass ratio of 1:40, stirred at 80 °C for 3 h. After stirring, it was filtered and washed 6 times with pure water, dried at 80 °C for 24 h, ground through a 200-mesh sieve. The sieved halloysite and the silane coupling agent solution were mixed at a mass ratio of 1:40, ultrasonicated for 10 min, and then reacted at 60 °C for 4 h. After reacting for 4 h, it was filtered and washed 6 times with pure water, dried at 80 °C for 24 h to obtain silane coupling agent-modified halloysite; the silane coupling agent-modified halloysite, 3-allyl-2-hydroxybenzaldehyde, perfluorobutylethylene, azobisisobutyronitrile, and chloroform were mixed at a mass ratio of 1:0.035:0.04:0.01:45, heated to 67 °C and refluxed for 7 h. After the reaction, it was filtered and washed 3 times with absolute ethanol, dried at 80 °C for 24 h to obtain pre-modified halloysite;

[0045] (4) Weigh iodine, tert-butyl hydroperoxide, potassium carbonate, and 2-hydrazino-5-bromopyridine according to a molar ratio of 0.2:2:1:1. The pre-modified halloysite, 2-hydrazino-5-bromopyridine, and 1,4-dioxane were mixed at a mass ratio of 1:0.045:45, iodine, tert-butyl hydroperoxide, and potassium carbonate were added, and the temperature was raised to 80 °C and reacted for 1.5 h. After the reaction, it was filtered and washed 2 times with a saturated sodium thiosulfate solution, then washed 3 times with pure water, and dried at 80 °C for 24 h to obtain modified halloysite;

[0046] (5) Weigh the following raw materials by mass parts: 100 parts of polyvinyl chloride resin, 6 parts of modified porphyrin, 15 parts of dioctyl terephthalate, 20 parts of modified polyurethane, 5 parts of epoxy soybean oil, 10 parts of aluminum hydroxide, 5 parts of magnesium hydroxide, 5 parts of calcium-zinc stabilizer, 10 parts of calcium chloride, and 6 parts of modified halloysite. The above raw materials were dried in a 60 °C vacuum drying oven for 12 h, then kneaded in a kneader. After kneading, the material was discharged and sent into a twin-screw extruder for extrusion molding; after extrusion, it was pressed and molded under the action of a flat vulcanizing machine to obtain a sheath layer material; the temperature of the kneader was 110 °C, the time was 25 min, the rotation speed was 150 rpm, the vulcanization temperature of the flat vulcanizing machine was 165 °C, the pressure was 10 MPa, and the time was 12 min.

[0047] Example 3:

[0048] A cold-resistant and freeze-resistant cable, and the preparation method of the sheath material includes the following preparation steps:

[0049] (1) Under anhydrous and anaerobic conditions, meso-tetra(4-pyridyl)porphyrin and 4-chloromethylphenylboronic acid were weighed according to a molar ratio of 1:4.2. Meso-tetra(4-pyridyl)porphyrin and chloroform were mixed at a mass ratio of 1:12, and the temperature was raised to 65 °C. 4-chloromethylphenylboronic acid was added and the reaction was carried out for 72 h. After the reaction was completed, filtration was carried out, followed by column chromatography, elution with the first eluent and elution with the second eluent. The second eluent was collected, and the product eluted with the second eluent was concentrated and vacuum dried to obtain modified porphyrin;

[0050] (2) Poly(tetrahydrofuran) glycol, dicyclohexylmethane-4,4'-diisocyanate, and 4-aminophenylboronic acid were weighed according to a molar ratio of 5:10:12. Poly(tetrahydrofuran) glycol and dimethylacetamide were mixed at a mass ratio of 1:4, heated to 60 °C, dicyclohexylmethane-4,4'-diisocyanate and dibutyltin dilaurate 0.005 times the volume of dimethylacetamide were added, and the reaction was carried out for 4 h under nitrogen protection. 4-aminophenylboronic acid was added and the reaction was continued for 8 h. After the reaction was completed, filtration was carried out and washed 3 times with pure water, and then vacuum dried to obtain modified polyurethane;

[0051] (3) Using a 90 wt% ethanol solution as a solvent, vinyltrimethoxysilane was formulated into a 2 wt% solution to obtain a silane coupling agent solution; halloysite and a 4 mol / L sodium hydroxide solution were mixed at a mass ratio of 1:40, stirred at 80 °C for 3 h. After stirring was completed, filtration was carried out and washed 6 times with pure water, dried at 80 °C for 24 h, ground through a 200-mesh sieve. The sieved halloysite and the silane coupling agent solution were mixed at a mass ratio of 1:40, ultrasonicated for 10 min, and then reacted at 60 °C for 4 h. After reacting for 4 h, filtration was carried out and washed 6 times with pure water, dried at 80 °C for 24 h to obtain silane coupling agent-modified halloysite; The silane coupling agent-modified halloysite, 3-allyl-2-hydroxybenzaldehyde, perfluorobutylethylene, azobisisobutyronitrile, and chloroform were mixed at a mass ratio of 1:0.04:0.05:0.01:50, the temperature was raised to 65 °C and refluxed for 6 h. After the reaction was completed, filtration was carried out and washed 3 times with absolute ethanol, dried at 80 °C for 24 h to obtain pre-modified halloysite;

[0052] (4) Iodine, tert-butyl hydroperoxide, potassium carbonate, and 2-hydrazinyl-5-bromopyridine were weighed according to a molar ratio of 0.2:2:1:1. The pre-modified halloysite, 2-hydrazinyl-5-bromopyridine, and 1,4-dioxane were mixed at a mass ratio of 1:0.05:50, iodine, tert-butyl hydroperoxide, and potassium carbonate were added, and the temperature was raised to 80 °C and reacted for 1 h. After the reaction was completed, filtration was carried out and washed 2 times with a saturated sodium thiosulfate solution, then washed 3 times with pure water, and dried at 80 °C for 24 h to obtain modified halloysite;

[0053] (5) Weigh the following raw materials by mass parts: 100 parts of polyvinyl chloride resin, 7 parts of modified porphyrin, 15 parts of dioctyl terephthalate, 25 parts of modified polyurethane, 5 parts of epoxidized soybean oil, 10 parts of aluminum hydroxide, 5 parts of magnesium hydroxide, 5 parts of calcium-zinc stabilizer, 10 parts of calcium chloride, and 7 parts of modified halloysite. Dry the above raw materials in a vacuum drying oven at 60 °C for 12 h, then carry out mixing in a mixer. After the mixing is completed, discharge the mixture and send it into a twin-screw extrusion granulator for extrusion molding; after extrusion, carry out compression molding under the action of a flat vulcanizing machine to obtain the sheath layer material; the temperature of the mixer is 100 °C, the time is 20 min, the rotation speed is 100 rpm, the vulcanization temperature of the flat vulcanizing machine is 160 °C, the pressure is 10 MPa, and the time is 12 min.

[0054] Comparative Example 1:

[0055] The difference between the preparation method of the sheath material in Comparative Example 1 and that in Example 2 is that step (5) is modified to: Weigh the following raw materials by mass parts: 100 parts of polyvinyl chloride resin, 15 parts of dioctyl terephthalate, 5 parts of epoxidized soybean oil, 10 parts of aluminum hydroxide, 5 parts of magnesium hydroxide, 5 parts of calcium-zinc stabilizer, 10 parts of calcium chloride. Dry the above raw materials in a vacuum drying oven at 60 °C for 12 h, then carry out mixing in a mixer. After the mixing is completed, discharge the mixture and send it into a twin-screw extrusion granulator for extrusion molding; after extrusion, carry out compression molding under the action of a flat vulcanizing machine to obtain the sheath layer material; the temperature of the mixer is 110 °C, the time is 25 min, the rotation speed is 150 rpm, the vulcanization temperature of the flat vulcanizing machine is 165 °C, the pressure is 10 MPa, and the time is 12 min.

[0056] Test Example 1:

[0057] Test of antibacterial performance:

[0058] Test method: Refer to the standard QB / T 2591-2003 to test the sheath materials prepared in the examples and comparative examples. The results are shown in Table 1.

[0059] Table 1 Test results of antibacterial performance

[0060] Antibacterial rate (%) Antibacterial rate (%) Example 1 97.57 Comparative Example 1 42.14 Example 2 97.55 Example 3 97.61

[0061] From the comparison of the experimental data of Examples 1 to 3 and Comparative Example 1 in Table 1, it can be found that the sheath material prepared by the present invention has good antibacterial properties; it shows that 4-chloromethylphenylboronic acid and meso-tetra(4-pyridyl)porphyrin are reacted to obtain modified porphyrin; chloromethyl reacts with pyridine to generate pyridine quaternary ammonium salt with antibacterial properties; secondly, 3-allyl-2-hydroxybenzaldehyde and perfluorobutylethylene are polymerized on the surface of halloysite treated with vinyltrimethoxysilane to obtain pre-modified halloysite; the pre-modified halloysite is reacted with 2-hydrazino-5-bromopyridine to obtain modified halloysite, and the aldehyde group on the hydroxybenzaldehyde structure of the pre-modified halloysite and the hydrazino group on 2-hydrazino-5-bromopyridine undergo nucleophilic addition, nucleophilic substitution, and dehydrogenation aromatization to generate a triazole structure, and the triazole structure has good antibacterial properties; finally, polyvinyl chloride resin, modified porphyrin, dioctyl terephthalate, modified polyurethane, epoxy soybean oil, aluminum hydroxide, magnesium hydroxide, calcium zinc stabilizer, and modified halloysite are kneaded and extruded, and then vulcanized by a flat vulcanizer to obtain a sheath material; bromine is introduced during the reaction of the pre-modified halloysite with 2-hydrazino-5-bromopyridine, and bromine and pyridine can regenerate pyridine quaternary ammonium salt during high-temperature kneading, further improving the antibacterial properties.

[0062] Test Example 2:

[0063] Testing of mechanical properties:

[0064] Test method: According to the standard of GB / T1040.2-2006, the tensile properties of the sheath materials prepared in the examples and comparative examples were tested on a tensile testing machine. The length of the sheath material was 25 mm, the width was 6 mm, and the thickness was 1 mm; the test gauge length was 20 mm, the tensile speed was 5 mm / min, and the tensile strength was recorded. The results are shown in Table 2.

[0065] Testing of anti-ultraviolet aging performance:

[0066] Test method: The sheath materials prepared in the examples and comparative examples were placed in an ultraviolet lamp box. There were 4 Q-Lab UVA340 ultraviolet lamps in the lamp box, the distance between the lamps was 10 cm, the distance between the specimen and the lamps was 5 cm, the central wavelength of the ultraviolet light was 340 nm, and the intensity was 13 mW / cm 2 , the size of the lamp box was 130 cm * 45 cm * 20 cm, and the irradiation time was 720 h. After the irradiation, the tensile strength was tested according to the mechanical property test method and the tensile strength retention rate before and after ultraviolet irradiation was calculated. The results are shown in Table 2.

[0067] Table 2 Test results of mechanical properties

[0068] Tensile strength (MPa) Tensile strength retention rate (%) Example 1 34.97 94.26 Example 2 35.13 94.97 Example 3 35.14 94.32 Comparative Example 1 25.47 83.21

[0069] From the comparison of the experimental data of Examples 1 to 3 and Comparative Example 1 in Table 2, it can be found that the sheath material prepared by the present invention has good mechanical properties and anti-ultraviolet aging properties. It shows that the modified polyurethane has good elasticity and can toughen the sheath material; secondly, 3-allyl-2-hydroxybenzaldehyde and perfluorobutylethylene are polymerized on the surface of halloysite treated with vinyltrimethoxysilane to obtain pre-modified halloysite; the surface of halloysite treated with vinyltrimethoxysilane contains a large number of double bonds, which can initiate the polymerization of 3-allyl-2-hydroxybenzaldehyde and perfluorobutylethylene on its surface under the action of an initiator, so that a fluorine element with low surface energy and a hydroxybenzaldehyde structure are grafted on the surface of halloysite; halloysite, as an inorganic filler, can enhance the mechanical properties of the sheath material, and the fluorine element with low surface energy can improve the weather resistance of the sheath material and provide hydrophobic properties; the pre-modified halloysite is reacted with 2-hydrazino-5-bromopyridine to obtain modified halloysite, and the aldehyde group on the hydroxybenzaldehyde structure of the pre-modified halloysite and the hydrazine group on 2-hydrazino-5-bromopyridine undergo nucleophilic addition, nucleophilic substitution, and dehydrogenation aromatization to generate a triazole structure, and the triazole structure forms an intramolecular chelate ring with the hydroxyl group on the hydroxybenzaldehyde, which can convert light energy into heat energy, thereby improving the anti-aging performance of the sheath material;

[0070] Finally, polyvinyl chloride resin, modified porphyrin, dioctyl terephthalate, modified polyurethane, epoxy soybean oil, aluminum hydroxide, magnesium hydroxide, calcium-zinc stabilizer, and modified halloysite are mixed and extruded, and then vulcanized by a flat vulcanizer to obtain a sheath material; during the high-temperature mixing process, the phenylboronic acid structure on the modified polyurethane can not only crosslink with the phenylboronic acid on the modified porphyrin, but also undergo self-crosslinking to form a dense crosslinked network, thereby improving the mechanical properties of the sheath material.

[0071] Test Example 3:

[0072] Test for cold resistance and frost resistance:

[0073] The cracking property of the sheath materials prepared in the examples and comparative examples was tested according to GB / T 2951.6-97, and the test temperature was -50°C. The results are shown in Table 3.

[0074] Test results of cold resistance and frost resistance

[0075] Cracking property Cracking property Example 1 No cracks Comparative Example 1 With cracks Example 2 No cracks Example 3 No cracks

[0076] From the comparison of the experimental data of Examples 1 to 3 and Comparative Example 1 in Table 3, it can be found that the sheath material prepared by the present invention has good cold resistance and antifreeze performance. It shows that the modified polyurethane is grafted with a phenylboronic acid structure; the modified polyurethane has good elasticity and can toughen the sheath material; secondly, 3-allyl-2-hydroxybenzaldehyde and perfluorobutylethylene are polymerized on the surface of halloysite treated with vinyltrimethoxysilane to obtain pre-modified halloysite; the surface of halloysite treated with vinyltrimethoxysilane contains a large number of double bonds, which can initiate the polymerization of 3-allyl-2-hydroxybenzaldehyde and perfluorobutylethylene on its surface under the action of an initiator, so as to graft a fluorine element with low surface energy and a hydroxybenzaldehyde structure on the surface of halloysite; halloysite, as an inorganic filler, can enhance the mechanical properties of the sheath material, and the fluorine element with low surface energy can improve the weather resistance of the sheath material; finally, polyvinyl chloride resin, modified porphyrin, dioctyl terephthalate, modified polyurethane, epoxy soybean oil, aluminum hydroxide, magnesium hydroxide, calcium-zinc stabilizer, and modified halloysite are mixed and extruded, and then vulcanized by a flat vulcanizer to obtain the sheath material; during the high-temperature mixing process, the phenylboronic acid structure on the modified polyurethane can not only crosslink with the phenylboronic acid on the modified porphyrin, but also undergo self-crosslinking to form a dense crosslinked network, thereby improving the mechanical properties of the sheath material.

[0077] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present invention. Any reference signs in the claims should not be construed as limiting the claims involved.

Claims

1. A cold-resistant and frost-resistant cable, characterized in that: The cold-resistant and frost-resistant cable comprises a sheath layer, an insulation layer, and a conductive core layer from the outside to the inside; the sheath layer is made of a sheath layer material; The preparation method of the sheath layer material comprises the following preparation steps: (1) Under anhydrous and oxygen-free conditions, weighing m-tetra(4-pyridyl)porphyrin and 4-chloromethylphenylboric acid in a molar ratio of 1:(4.1-4.2), mixing m-tetra(4-pyridyl)porphyrin and chloroform in a mass ratio of 1:(10-12), heating to 65-70° C., adding 4-chloromethylphenylboric acid and reacting for 72 hours, filtering and column chromatography after the reaction, eluting with a first eluent, eluting with a second eluent, collecting the second eluent, concentrating and vacuum drying the eluted product of the second eluent to obtain a modified porphyrin; (2) Weigh polytetrahydrofuran ether diol, dicyclohexylmethane-4,4'-diisocyanate, and 4-aminophenylboronic acid in a molar ratio of 5:10:12, mix polytetrahydrofuran ether diol and dimethylacetamide in a mass ratio of 1:(3-4), heat to 60° C., add dibutyltin dilaurate in an amount of 0.003-0.005 times the volume of dicyclohexylmethane-4,4'-diisocyanate and dimethylacetamide, react for 4 h under nitrogen protection, add 4-aminophenylboronic acid, continue to react for 8 h, filter and wash with pure water 3-4 times after the reaction, and vacuum dry to obtain modified polyurethane; (3) mixing silane coupling agent modified halloysite, 3-allyl-2-hydroxybenzaldehyde, perfluorobutylethylene, azobisisobutyronitrile, and chloroform in a mass ratio of 1:(0.03-0.04):(0.03-0.05):0.01:(40-50), heating to 65-70° C. and reflux reaction for 6-8 hours. After the reaction is completed, filtering and washing with anhydrous ethanol for 3-4 times, and drying at 80° C. for 24 hours to obtain pre-modified halloysite; (4) iodine, tert-butyl hydroperoxide, potassium carbonate, and 2-hydrazino-5-bromopyridine were weighed in a molar ratio of 0.2:2:1:1, and pre-modified halloysite, 2-hydrazino-5-bromopyridine, and 1,4-dioxane were mixed in a mass ratio of 1:(0.04-0.05):(40-50), iodine, tert-butyl hydroperoxide, and potassium carbonate were added, and the temperature was raised to 80° C. for reaction for 1-2 h. After the reaction was completed, the mixture was filtered and washed with a saturated sodium thiosulfate solution for 2-3 times, and then washed with pure water for 3-4 times, and dried at 80° C. for 24 h to obtain modified halloysite; (5) The following raw materials are weighed by mass: 100 parts of polyvinyl chloride resin, 5-7 parts of modified porphyrin, 15 parts of dioctyl terephthalate, 15-25 parts of modified polyurethane, 5 parts of epoxy soybean oil, 10 parts of aluminum hydroxide, 5 parts of magnesium hydroxide, 5 parts of calcium zinc stabilizer, 10 parts of calcium chloride, and 5-7 parts of modified halloysite. The above raw materials are dried in a vacuum drying oven at 60° C. for 12 h, and then mixed in an internal mixer. After mixing, the material is discharged and sent to a twin-screw extruder granulator for extrusion molding; after extrusion, it is pressed and molded under the action of a flat vulcanizer to obtain a sheath layer material.

2. A cold-resistant and frost-resistant cable according to claim 1, characterized in that: The column chromatography used in step (1) is a silica gel chloroform column; the first eluent is a mixture of chloroform and methanol in a mass ratio of 10:1; the second eluent is a mixture of chloroform and methanol in a mass ratio of 5:

1.

3. A cold-resistant and frost-resistant cable according to claim 1, characterized in that: The preparation method of the silane coupling agent modified halloysite in step (3) is as follows: halloysite and 4 mol / L sodium hydroxide solution are mixed in a mass ratio of 1:40, stirred at 80°C for 3h, filtered after stirring and washed with pure water 6 times, dried at 80°C for 24h, ground through a 200-mesh sieve, and the sieved halloysite and silane coupling agent solution are mixed in a mass ratio of 1:40, ultrasonicated for 10min, reacted at 60°C for 4h, filtered after reacting for 4h, washed with pure water 6 times, and dried at 80°C for 24h to obtain silane coupling agent modified halloysite.

4. A cold-resistant and frost-resistant cable according to claim 1, characterized in that: In step (5), the temperature of the internal mixer is 100-120° C., the time is 20-30 min, the speed is 100-200 rpm, and the vulcanizing temperature of the flat vulcanizing press is 160-170° C., the pressure is 10 MPa, and the time is 12 min.

5. The cold-resistant and frost-resistant cable according to claim 1, characterized in that: The polyvinyl chloride resin in step (5) is of S-70 grade; the calcium zinc stabilizer is of 9876 grade.

6. A cold-resistant and frost-resistant cable according to claim 3, characterized in that: The preparation method of the silane coupling agent solution is as follows: using 90 wt % ethanol solution as a solvent, preparing vinyl trimethoxysilane into a 2 wt % solution to obtain the silane coupling agent solution.