Fireproof polyvinyl chloride cable sheath, its preparation method and cable

Abstract

The application relates to the technical field of cables, and particularly discloses a fireproof polyvinyl chloride cable sheath, a preparation method thereof and a cable. The fireproof polyvinyl chloride cable sheath comprises the following raw materials in parts by weight: polyvinyl chloride resin 30-40 parts, methyl vinyl silicone rubber 10-20 parts, filler 3-6 parts, anti-aging agent 1-3 parts, antioxidant 1-5 parts, fireproof agent 9-12 parts and compound 6-15 parts; the preparation method is as follows: the polyvinyl chloride resin, the methyl vinyl silicone rubber and the compound are uniformly mixed, heated and melted to obtain a mixture; the filler, the anti-aging agent, the antioxidant and the fireproof agent are added into the mixture, uniformly stirred and extruded into a shape to obtain the fireproof polyvinyl chloride cable sheath. The fireproof polyvinyl chloride cable sheath has the advantages of improving the fireproof performance of the cable through the synergistic effect of the raw materials.

Description

TECHNICAL FIELD

[0001] The application relates to the cable technology field, in particular to a fireproof polyvinyl chloride cable sheath and a preparation method thereof and a cable. BACKGROUND

[0002] The wire and cable industry is an important supporting industry of China's economic construction, is widely used in various fields of the national economy, accounts for one fourth of the Chinese electrical industry, and is the second largest industry in the mechanical industry next to the automobile industry. Among them, the wire used for indoor decoration is mainly polyvinyl chloride cable with a rated voltage of 450 / 750V and below.

[0003] With the development of cities in China, the demand for cables is gradually increasing, but if the cables are not used properly, burning will occur, which will have a great impact on the surrounding environment and pose a serious safety threat to on-site personnel, so fireproof cables have entered people's field of vision. The sheath in the fireproof cable plays a crucial role, and the cable sheath is the outermost layer of the cable and is the most important barrier to protect the safety of the internal structure of the cable.

[0004] At present, although the cable has certain fireproof performance, when a fire occurs, the cable sheath will be burned for a long time and will also be burned off, which is very easy to cause the situation of electric leakage, and the fire rescue work has a great safety hazard. SUMMARY

[0005] In order to improve the fireproof property of the cable, the application provides a fireproof polyvinyl chloride cable sheath and a preparation method thereof and a cable.

[0006] In the first aspect, the application provides a fireproof polyvinyl chloride cable sheath, which adopts the following technical scheme:

[0007] A fireproof polyvinyl chloride cable sheath comprises the following raw materials by weight: polyvinyl chloride resin 30-40 parts, methyl vinyl silicone rubber 10-20 parts, filler 3-6 parts, anti-aging agent 1-3 parts, antioxidant 1-5 parts, fire retardant 9-12 parts, and composite 6-15 parts; wherein the composite is modified organic montmorillonite loaded with 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo-octane.

[0008] Through the above technical scheme, the fireproof polyvinyl chloride cable sheath of the application has the synergistic effect of the raw materials, not only maintains the optimal tensile strength of the sheath, but also improves the fireproof property of the cable, wherein the tensile strength of the sheath is 12.5-12.8 MPa, the oxygen index is 37.1-43.5%, and the burning degree of the cable is 1.5-5.4%.

[0009] The polyvinyl chloride resin is a basic raw material, and a certain amount of methyl vinyl silicone rubber can improve the anti-aging property of the sheath, and can also improve the compatibility with the filler. The filler can not only maintain the relatively optimal mechanical strength of the sheath, but also can play a certain flame-retardant and fireproof role. The anti-aging agent can prevent the sheath from aging and prolong the service life. The antioxidant can reduce the contact with oxygen when the sheath is on fire, and prevent the fire trend from expanding. The fire retardant added to the raw material of the sheath can further improve the fireproof performance of the sheath.

[0010] The composite is 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo-octane loaded on modified organic montmorillonite. First, the chemical structure of the modified organic montmorillonite is composed of a layered silicate mineral, and water molecules are sandwiched in the layered structure. This structure also makes it have strong adsorption performance, which can adsorb surrounding water molecules and organic molecules. When high temperature is encountered, water molecules will be evaporated, and organic molecules will be decomposed, thereby releasing a large amount of water vapor and organic gas, which will absorb the surrounding heat, thereby forming a heat insulation layer to prevent the spread of the flame; at the same time, the layered structure of the montmorillonite will change, forming a structure similar to foam, further enhancing the heat insulation performance. The modified organic montmorillonite has a special structure, which makes it have a loading property. By loading 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo-octane, 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo-octane can be inserted into the pores of the modified organic montmorillonite. 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo-octane has high temperature resistance and water resistance, and has a hydroxyl group at the end. It is a reactive intumescent flame retardant with strong flame-retardant and heat-insulating effect. Loading on the modified organic montmorillonite can not only improve the compatibility of the modified organic montmorillonite with other materials of the sheath, but also through the synergistic effect between the two, can further improve the fireproof performance of the sheath.

[0011] As preferred: the composite is prepared by the following method:

[0012] A1: Put the modified organic montmorillonite into water, ultrasonic dispersion, heating and warming to get solution A;

[0013] A2: Put 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo-octane into dimethyl sulfoxide, ultrasonic dispersion to get solution B;

[0014] A3: Keep the temperature of solution A, and drop solution B into solution A, constant temperature stirring, centrifugation, take the solid, wash, dry to get the composite.

[0015] Further, the composite is prepared by the following method:

[0016] A1: Put the modified organic montmorillonite into water, ultrasonic dispersion for 20-40 min, heat to 50-60℃, to obtain solution A; A2: Put 1-oxo-4-hydroxymethyl-2, 6, 7-trioxy-1-phosphabicyclo-octane into dimethyl sulfoxide, ultrasonic dispersion for 20-40 min, to obtain solution B;

[0017] A3: Keep 50-60℃, and drop solution B into solution A at a speed of 3-5 mL / min, constant temperature stirring, centrifugation, take the solid, wash with methanol solution for 5-7 times, and dry to obtain the composite.

[0018] In the above, the amount of water added in step A1 is 4-6 mL per 1 g of modified organic montmorillonite, the amount of dimethyl sulfoxide added in step A2 is 2-4 mL per 1 g of 1-oxo-4-hydroxymethyl-2, 6, 7-trioxy-1-phosphabicyclo-octane, and the mass fraction of the methanol solution in step A3 is 47%.

[0019] By using the above technical solution, the 1-oxo-4-hydroxymethyl-2, 6, 7-trioxy-1-phosphabicyclo-octane is better intercalated in the modified organic montmorillonite, which facilitates the better play of the two and improves the fire resistance of the sheath.

[0020] As a preferred, the weight ratio of the modified organic montmorillonite and 1-oxo-4-hydroxymethyl-2, 6, 7-trioxy-1-phosphabicyclo-octane is 1:(3-5).

[0021] If the amount of 1-oxo-4-hydroxymethyl-2, 6, 7-trioxy-1-phosphabicyclo-octane is too small, the fire resistance of the composite compounded with the modified organic montmorillonite cannot reach the optimum; if the amount of 1-oxo-4-hydroxymethyl-2, 6, 7-trioxy-1-phosphabicyclo-octane is too much, when the modified organic montmorillonite reaches saturation, it will not load 1-oxo-4-hydroxymethyl-2, 6, 7-trioxy-1-phosphabicyclo-octane, which will cause waste of raw materials. By using the above technical solution, when the amount of 1-oxo-4-hydroxymethyl-2, 6, 7-trioxy-1-phosphabicyclo-octane and modified organic montmorillonite is in the above range, the composite compounded by the two can reach a better fire resistance.

[0022] As a preferred, the modified organic montmorillonite is prepared by the following method: put the organic montmorillonite into acetic acid solution, mix uniformly, stand, filter, take out the solid, wash, and dry to obtain the modified organic montmorillonite.

[0023] Further, the modified organic montmorillonite is prepared by the following method: the organic montmorillonite is put into acetic acid solution, mixed uniformly, and then left for 10-14 hours, filtered, and the solid is taken out and washed with water for 5-7 times, and then dried to obtain the modified organic montmorillonite; wherein the addition amount of acetic acid solution is 2-4 mL per 1 g of the organic montmorillonite, and the mass fraction of the acetic acid solution is 60%.

[0024] By using the above technical solution, the organic montmorillonite is treated by the acetic acid solution, which can reduce the metal oxides or inorganic salts and other impurities between the layers of the organic montmorillonite, and make the pore structure unblocked; meanwhile, the potassium ions, sodium ions, calcium ions and other ions between the layers of the organic montmorillonite can be ion-exchanged with the hydrogen ions in the acetic acid solution to become soluble acid salts, and the hydrogen ions have a smaller radius than the replaced ions, so that the crystal lattice between the layers of the organic montmorillonite is broken and the interlayer distance is expanded, thereby increasing the specific surface area and improving the adsorption capacity, which is convenient for loading 1-oxo-4-hydroxymethyl-2, 6, 7-trioxy-1-phosphabicyclo-octane, and helps to further improve the fire resistance of the composite, thereby improving the fire resistance of the sheath.

[0025] As a preferred, the filler is a mixture of micro-fine talc powder, mica powder and mullite powder, and the weight ratio of the micro-fine talc powder, the mica powder and the mullite powder is 1:1:1.

[0026] By using the above technical solution, the micro-fine talc powder can release a large amount of water vapor at high temperature, absorb heat and reduce the temperature in the combustion process, thereby slowing down the speed of fire spread and playing a role in flame retardation. The mica powder has good self-extinguishing performance, and can also release water vapor to cool the heating area when combustion occurs, thereby playing a role in controlling combustion. The mullite powder has the characteristics of high temperature resistance and oxidation resistance, and can also play a role in flame retardation. In addition, the three can also improve the strength of the sheath and improve the comprehensive performance of the sheath when added to the raw materials of the sheath.

[0027] As a preferred, the fire retardant includes magnesium hydroxide, decabromobiphenyl ethane and antimony trioxide, and the weight ratio of the magnesium hydroxide, the decabromobiphenyl ethane and the antimony trioxide is 1:1:1.

[0028] By using the above technical solution, the magnesium hydroxide can release combined water when heated to absorb a large amount of heat, thereby reducing the surface temperature of the flame and achieving the effect of slowing down the spread of fire. The decabromobiphenyl ethane and the antimony trioxide can also absorb a large amount of heat around them, and use their pyrolysis to achieve the purpose of flame retardation. Through the synergistic effect of the three, the fire resistance of the sheath can be further improved.

[0029] Preferably, the magnesium hydroxide is pretreated by the following method before use: the magnesium hydroxide is put into water, urea is added, ultrasonic dispersion is performed, heating is performed to increase the temperature, and well-dispersed magnesium hydroxide is obtained; the tin chloride, zinc oxide and potassium hydroxide are put into water, heating is performed to increase the temperature, and the well-dispersed magnesium hydroxide is added, heating is performed again to increase the temperature, constant temperature stirring is performed, reaction is performed, suction filtration is performed, washing is performed, and drying is performed to obtain pretreated magnesium hydroxide.

[0030] Further, the magnesium hydroxide is pretreated by the following method before use: the magnesium hydroxide is put into water, urea is added, ultrasonic dispersion is performed for 20-40 min, heating is performed to increase the temperature to 40-60℃, and well-dispersed magnesium hydroxide is obtained; the tin chloride, zinc oxide and potassium hydroxide are put into water, heating is performed to increase the temperature to 40-60℃, and the well-dispersed magnesium hydroxide is added, heating is performed again to increase the temperature to 80-90℃, constant temperature stirring is performed for 5-7 h, reaction is performed, suction filtration is performed, washing is performed with water for 5-7 times, and drying is performed to obtain pretreated magnesium hydroxide.

[0031] In the method, the amount of water added twice is 4-6 mL per 1 g of magnesium hydroxide, the weight ratio of the magnesium hydroxide to the urea is 1:(0.6-0.8), the weight ratio of the magnesium hydroxide to the tin chloride is 1:(0.4-0.6), the weight ratio of the magnesium hydroxide to the zinc oxide is 1:(0.2-0.4), and the weight ratio of the magnesium hydroxide to the potassium hydroxide is 1:(0.2-0.4).

[0032] By using the above technical solution, the magnesium hydroxide is treated by the above method, which can not only improve the compatibility of the magnesium hydroxide with other raw materials of the sheath, but also greatly improve the oxygen index of the magnesium hydroxide and the smoke suppression property, thereby further improving the fireproof property of the sheath.

[0033] In a second aspect, the application provides a preparation method of a fireproof polyvinyl chloride cable sheath, which adopts the following technical solution:

[0034] The preparation method of the fireproof polyvinyl chloride cable sheath comprises the following steps:

[0035] S1: uniformly mixing polyvinyl chloride resin, methyl vinyl silicone rubber and a compound, and heating and melting to obtain a mixture;

[0036] S2: adding fillers, anti-aging agents, antioxidants and fireproof agents into the mixture, uniformly stirring, and extruding to form a fireproof polyvinyl chloride cable sheath.

[0037] Further, the preparation method of the fireproof polyvinyl chloride cable sheath comprises the following steps:

[0038] S1: uniformly mixing polyvinyl chloride resin, methyl vinyl silicone rubber and a compound, and heating and melting at a temperature of 260-280℃ to obtain a mixture;

[0039] S2: adding the filler, the antioxidant, the antioxygen, and the fireproof agent into the mixture, stirring uniformly, and extruding to form a fireproof polyvinyl chloride cable sheath.

[0040] By using the above technical scheme, the sheath is prepared by using the above method, so that the mixing of the raw materials is more uniform, and the fireproof property of the sheath is improved.

[0041] In a third aspect, the application provides a fireproof polyvinyl chloride cable, which adopts the following technical scheme:

[0042] A fireproof polyvinyl chloride cable, which comprises the fireproof polyvinyl chloride cable sheath according to any one of claims 1-6.

[0043] By using the above technical scheme, the cable made of the sheath has better fireproof property.

[0044] In summary, the application has at least one of the following beneficial technical effects:

[0045] 1. In the application, the composite is prepared by using modified organic montmorillonite loaded with 1-oxo-4-hydroxymethyl-2, 6, 7-trioxy-1-phosphabicyclo-octane, both of which have fire-retardant and fireproof effects, and through the synergistic effect between them, the fireproof property of the cable sheath is further improved while the mechanical properties of the cable are maintained, the tensile strength of the sheath can reach 12.8 MPa, the oxygen index can reach 43.5%, and the burning loss of the cable can be reduced to 1.5%.

[0046] 2. In the application, the magnesium hydroxide is preferably pretreated before use, which can not only improve the compatibility of the magnesium hydroxide with other raw materials of the sheath, but also greatly improve the oxygen index of the magnesium hydroxide and the smoke suppression property, thereby further improving the fireproof property of the sheath. DETAILED DESCRIPTION

[0047] The application will be further described in detail below in combination with specific contents.

[0048] Raw materials

[0049] The raw materials of the application can be obtained on the market.

[0050] The polyvinyl chloride resin has a CAS number of 9002-86-2, is an industrial grade, and has a molecular weight of 62.49822; the methyl vinyl silicone rubber has a CAS number of 68037-87-6, a molecular weight of 118.2819, and a density of 0.98 g / cm 3 , a specific gravity of 0.96, a melting point of <-20℃, a boiling point of >200℃, and a flash point of >110℃; and the fine talc powder has an average particle size of 0.6 g / cm 3Mica powder average particle size is 30 μm; mullite powder average particle size is 600 μm; anti-aging agent is anti-aging agent 264; antioxidant is antioxidant 1010.

[0051] Preparation Example

[0052] Preparation Example 1

[0053] A modified organic montmorillonite is prepared by the following method:

[0054] 2 kg of organic montmorillonite is put into 6 L of 60% by mass acetic acid solution, mixed uniformly, left to stand for 12 h, filtered, the solid is taken out, washed with water for 6 times, and dried to obtain the modified organic montmorillonite.

[0055] Preparation Example 2

[0056] A composite is prepared by the following method:

[0057] A1: 2 kg of the modified organic montmorillonite prepared by the preparation example 1 is put into 10 L of water, ultrasonic dispersed for 30 min, heated to 55 °C to obtain solution A;

[0058] A2: 6 kg of 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo-octane is put into dimethyl sulfoxide, ultrasonic dispersed for 30 min to obtain solution B;

[0059] A3: keep 55 °C, and drop solution B into solution A at a speed of 4 mL / min, constant temperature stirring, centrifugal, take the solid, wash with 47% by mass methanol solution for 6 times, and dry to obtain the composite;

[0060] In step A2, the addition amount of dimethyl sulfoxide is 3 mL per 1 g of 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo-octane.

[0061] Preparation Example 3

[0062] A composite, which is different from the preparation example 1 in that the addition amount of 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo-octane is different, the addition amount of 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo-octane in the preparation example 3 is 8 kg.

[0063] Preparation Example 4

[0064] A composite, which is different from the preparation example 1 in that the addition amount of 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo-octane is different, the addition amount of 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo-octane in the preparation example 4 is 10 kg.

[0065] Preparation Example 5

[0066] A composite, which is different from Preparation Example 1 in that the amount of 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo-octane added is different, the amount of 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo-octane added in Preparation Example 5 is 2 kg.

[0067] Preparation Example 6

[0068] A composite, which is different from Preparation Example 1 in that the amount of 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo-octane added is different, the amount of 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo-octane added in Preparation Example 6 is 15 kg.

[0069] Example

[0070] Example 1

[0071] A fireproof polyvinyl chloride cable sheath, the raw material ratio of which is shown in Table 1.

[0072] A preparation method of a fireproof polyvinyl chloride cable sheath, comprising the following steps:

[0073] S1: uniformly mixing polyvinyl chloride resin, methyl vinyl silicone rubber and the composite prepared by Preparation Example 2, and heating and melting at a temperature of 270 DEG C to obtain a mixture;

[0074] S2: adding fillers, anti-aging agents, antioxidants and fireproof agents into the mixture, uniformly stirring, and extruding to form a fireproof polyvinyl chloride cable sheath.

[0075] Examples 2-5

[0076] A fireproof polyvinyl chloride cable sheath, which is different from Example 1 in that the raw material ratio of the sheath is different, the raw material ratio of which is shown in Table 1.

[0077] Table 1: the amount of each raw material in the sheath of Examples 1-5 (unit: kg)

[0078]

[0079] Example 6

[0080] A fireproof polyvinyl chloride cable sheath, which is different from Example 4 in that the source of the composite in the sheath is different, the composite in Example 6 being prepared by Preparation Example 3.

[0081] Example 7

[0082] A fireproof polyvinyl chloride cable sheath, which is different from example 4 in that the source of the compound in the sheath is different, and the compound in example 7 is prepared by preparation example 4.

[0083] Example 8

[0084] A fireproof polyvinyl chloride cable sheath, which is different from example 4 in that the source of the compound in the sheath is different, and the compound in example 8 is prepared by preparation example 5.

[0085] Example 9

[0086] A fireproof polyvinyl chloride cable sheath, which is different from example 4 in that the source of the compound in the sheath is different, and the compound in example 9 is prepared by preparation example 6.

[0087] Example 10

[0088] A fireproof polyvinyl chloride cable sheath, which is different from example 6 in that the magnesium hydroxide in the sheath raw material is pretreated before use by the following method: the magnesium hydroxide is put into water, urea is added, ultrasonic dispersion is carried out for 30 min, heating is carried out to 50℃, and the dispersed magnesium hydroxide is obtained; tin chloride, zinc oxide, potassium hydroxide are put into water, heating is carried out to 50℃, and the dispersed magnesium hydroxide is added, heating is carried out to 85℃ again, constant temperature stirring is carried out for 6h, reaction is carried out, suction filtration is carried out, water washing is carried out for 6 times, and drying is carried out, and the pretreated magnesium hydroxide is obtained.

[0089] Among them, the adding amount of water is 5mL twice for every 1g of magnesium hydroxide, the weight ratio of magnesium hydroxide and urea is 1:0.7, the weight ratio of magnesium hydroxide and tin chloride is 1:0.5, the weight ratio of magnesium hydroxide and zinc oxide is 1:0.3, and the weight ratio of magnesium hydroxide and potassium hydroxide is 1:0.3.

[0090] Comparative example

[0091] Comparative example 1

[0092] A fireproof polyvinyl chloride cable sheath, which is different from example 1 in that the compound is not added in the sheath raw material.

[0093] Comparative example 2

[0094] A fireproof polyvinyl chloride cable sheath, which is different from example 1 in that the compound in the sheath raw material is replaced by an equal amount of modified organic montmorillonite.

[0095] Comparative example 3

[0096] A fireproof polyvinyl chloride cable sheath, which is different from example 1 in that the complex in the sheath raw material is replaced by 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo-octane in equal amount.

[0097] Comparative example 4

[0098] A fireproof polyvinyl chloride cable sheath, which is different from example 1 in that the modified organic montmorillonite in the sheath raw material complex is replaced by organic montmorillonite in equal amount.

[0099] Application example

[0100] Application example 1

[0101] A fireproof polyvinyl chloride cable, which is prepared by winding the sheath prepared in example 1 around the conductor wire to obtain the fireproof polyvinyl chloride cable.

[0102] Application examples 2-10

[0103] A fireproof polyvinyl chloride cable, which is different from application example 1 in that the sheath in application examples 2-10 is prepared by using examples 2-10 respectively.

[0104] Application comparative examples 1-4

[0105] A fireproof polyvinyl chloride cable, which is different from application example 1 in that the sheath in application comparative examples 1-4 is prepared by using comparative examples 1-4 respectively.

[0106] Performance detection test

[0107] The fireproof polyvinyl chloride cable sheaths in examples 1-10 and comparative examples 1-4 are subjected to the following performance detection:

[0108] Tensile strength: the tensile strength of the sheath is determined according to GB / T1040.3-2006 "Determination of tensile properties of plastics-Part 3: test conditions for films and sheets", and the detection results are shown in Table 2.

[0109] Oxygen index: the oxygen index of the sheath is determined according to GB / T2406.2-2009 "Determination of the flammability of plastics-Part 2: burning behaviour of small specimens in testings using a 50 W horizontal specimen", and the detection results are shown in Table 2.

[0110] The fireproof polyvinyl chloride cables in application examples 1-10 and application comparative examples 1-4 are subjected to the following performance detection:

[0111] Fire resistance test: According to GB-T 19216.21-2003 "Test methods for resistance to flame of cables or optical cables", the fire resistance of the fireproof PVC cable sheath was tested, the supply fire temperature was 1200℃ and 1400℃ respectively, and the duration was 120min. The test results are shown in Table 3.

[0112] Burn-off degree: the cable was cut into 15cm length, then vertically placed, and burned by a burner with a heat power of 500W for 15s, the flame height was 125mm, then stopped for 15s, repeated for five times, the flame burning time was recorded, and the cable burn-off degree was calculated, burn-off degree=(weight before burning-weight after burning) / weight before burning x 100%, the test results are shown in Table 3.

[0113] Table 2 test results

[0114]

[0115] Table 3 test results

[0116]

[0117] From Table 2 and Table 3, it can be seen that the fireproof PVC cable sheath of the present application, through the synergistic effect between the raw materials, not only makes the sheath maintain a relatively good tensile strength, but also improves the fire resistance of the cable, wherein the tensile strength of the sheath is 12.5-12.8MPa, the oxygen index is 37.1-43.5%, and the burn-off degree of the cable is 1.5-5.4%.

[0118] From Example 1 and Comparative Examples 1-4, it can be seen that the tensile strength of the sheath in Example 1 is 12.5MPa, and the oxygen index is 37.4%, which is better than Comparative Examples 1-4. In combination with Application Example 1 and Application Comparative Examples 1-4, it can be seen that the cable in Application Example 1 has no obvious damage to the line at 1200℃, and the line is obviously damaged at 1400℃, and the burn-off degree is 3.1%, which is better than Application Comparative Examples 1-4, indicating that the use of modified organic montmorillonite loaded with 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo-octane in the raw materials of the cable sheath is more suitable, and can more improve the fire resistance of the cable.

[0119] It can be seen from the combination of Example 1 and Examples 8-9 that the tensile strength of the sheath in Example 1 is 12.5 MPa, and the oxygen index is 37.4%, which is superior to other examples, and it can be seen from the combination of Application Example 1 and Application Examples 8-9 that the cable in Application Example 1 has no obvious damage to the line at 1200℃, and the line is obviously damaged at 1400℃, and the burning loss degree is 3.1%, which is superior to Application Examples 8-9, indicating that the addition amount of modified organic montmorillonite and 1-oxo-4-hydroxymethyl-2, 6, 7-trioxy-1-phosphabicyclo-octane in the range specified in the present application is more appropriate, and can more improve the fire resistance of the cable.

[0120] It can be seen from the combination of Example 4, Example 6-7 that the tensile strength of the sheath in Example 6 is 12.7 MPa, and the oxygen index is 43.3%, which is superior to other examples, and it can be seen from the combination of Application Example 4 and Application Examples 6-7 that the cable in Application Example 6 has no obvious damage to the line at 1200℃, and the line has no obvious damage at 1400℃, and the burning loss degree is 1.7%, which is superior to other application examples, indicating that the use of the compound prepared in Preparation Example 3 is more appropriate, not only can the sheath maintain a relatively optimal tensile strength, but also can improve the fire resistance of the cable.

[0121] It can be seen from the combination of Example 6 and Example 10 that the tensile strength of the sheath in Example 10 is 12.8 MPa, and the oxygen index is 43.5%, which is superior to Example 6, and it can be seen from the combination of Application Example 6 and Application Example 10 that the cable in Application Example 10 has no obvious damage to the line at 1200℃, and the line has no obvious damage at 1400℃, and the burning loss degree is 1.5%, which is superior to Application Example 6, indicating that the pretreatment of magnesium hydroxide before use is more appropriate, and can more improve the fire resistance of the cable.

[0122] The examples of the above specific embodiments are the preferred embodiments of the present application, but do not limit the protection scope of the present application, so: any equivalent changes made according to the structure, shape, principle of the present application should be covered within the protection scope of the present application.

Claims

1. A fire resistant polyvinyl chloride cable jacket characterized by: It includes the following raw materials by weight: polyvinyl chloride resin 30-40 parts, methyl vinyl silicone rubber 10-20 parts, filler 3-6 parts, antioxidant 1-3 parts, antioxidant 1-5 parts, fire retardant 9-12 parts, compound 6-15 parts; wherein the compound is modified organic montmorillonite loaded 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo-octane; the filler is a mixture of fine talc powder, mica powder and mullite powder, and the weight ratio of fine talc powder, mica powder and mullite powder is 1:1:1; the fire retardant includes magnesium hydroxide, decabromodiphenyl ethane and antimony trioxide, and the weight ratio of magnesium hydroxide, decabromodiphenyl ethane and antimony trioxide is 1:1:1; the magnesium hydroxide is pretreated before use by the following method: put the magnesium hydroxide into water, add urea, ultrasonic dispersion, heat and warm up, get well dispersed magnesium hydroxide; put tin chloride, zinc oxide and potassium hydroxide into water, heat and warm up, and add well dispersed magnesium hydroxide, heat and warm up again, constant temperature stirring, reaction, suction filtration, washing, drying, get pretreated magnesium hydroxide; The compound is prepared by the following method: A1: Put the modified organic montmorillonite into water, ultrasonic dispersion, heat and warm up, get solution A; A2: Put 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo-octane into dimethyl sulfoxide, ultrasonic dispersion, get solution B; A3: Keep the temperature of solution A, and add solution B dropwise into solution A, constant temperature stirring, centrifugation, take the solid, washing, drying, get the compound; The modified organic montmorillonite is prepared by the following method: put the organic montmorillonite into acetic acid solution, mix evenly, stand, filter, take out the solid, washing, drying, get the modified organic montmorillonite.

2. A fire resistant polyvinyl chloride cable jacket according to claim 1, characterized in that: The weight ratio of the modified organic montmorillonite and 1-oxo-4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclo-octane is 1:(3-5).

3. A process for the production of a fire resistant polyvinyl chloride cable sheath as claimed in any one of claims 1-2, characterized in that, Including the following steps: S1: Mix polyvinyl chloride resin, methyl vinyl silicone rubber and compound evenly, heat and melt, get the mixture; S2: Add filler, antioxidant, antioxidant and fire retardant into the mixture, stir evenly, extrude into shape, get fireproof polyvinyl chloride cable sheath.

4. A fire resistant polyvinyl chloride cable, characterized by: It includes the fireproof polyvinyl chloride cable sheath as claimed in any one of claims 1-2. It includes the fireproof polyvinyl chloride cable sheath as claimed in any one of claims 1-2.

Images