CN113861546A

CN113861546A - Fireproof cable and preparation method thereof

Info

Publication number: CN113861546A
Application number: CN202111223944.1A
Authority: CN
Inventors: 李湘岳; 王立东
Original assignee: Rongweida Photoelectric Dongguan Co ltd
Current assignee: Rongweida Photoelectric Dongguan Co ltd
Priority date: 2021-10-20
Filing date: 2021-10-20
Publication date: 2021-12-31

Abstract

The application relates to the technical field of cables, and particularly discloses a fireproof cable and a preparation method thereof, wherein the fireproof cable comprises a conductive core layer and an outer sheath layer, and the outer sheath layer is prepared from the following raw materials in parts by weight: 80-90 parts of fluoroether rubber, 20-30 parts of hydrogenated nitrile rubber, 10-20 parts of superfine spherical alumina, 10-20 parts of polycarbonate polyurethane and 10-15 parts of pentabromoethyl benzene. The tensile strength change rates of oxalic acid resistance and sodium hydroxide resistance of the fireproof cable are-4.2% and-3.4% respectively at the lowest, and the elongation at break change rates are 13.2% and 12.5% respectively at the highest, so that the fireproof cable shows excellent corrosion resistance. Meanwhile, the elongation at break of the fireproof cable after aging is up to 162%, the oxygen index and the combustion performance level are up to 35.7% and B1 respectively, and the fireproof cable is a flame-retardant material and has excellent flame retardance.

Description

Fireproof cable and preparation method thereof

Technical Field

The application relates to the field of cables, in particular to a fireproof cable and a preparation method thereof.

Background

Cable, refers to materials used in power, communication and related transmission applications. According to different applications, cables are classified into power cables, shielded cables, high-temperature cables, computer cables, signal cables, and the like, which are composed of a conductive core layer and an insulating outer sheath layer for connecting circuits, electric appliances, and the like.

The fireproof cable is a cable with a flame retardant effect manufactured for ensuring data safety, can maintain enough time to return all data to a cage before the whole network is broken down after a fire occurs, and transfers the data to a safe place, so that the possibility of data loss is reduced to the minimum.

With the development of economy, the application of the fireproof cable is more and more extensive, and the use scenes are more and more. However, most fireproof cables are exposed outside for a long time and are extremely easy to be corroded by rainwater or air, and the insulating outer sheath layer of the fireproof cables is weak in corrosion resistance and easy to be corroded and broken, so that the conductive inner core cannot be protected, and the service life of the fireproof cables is relatively shortened.

Disclosure of Invention

In order to improve the corrosion resistance of the fireproof cable, the application provides the fireproof cable and the preparation method thereof.

In a first aspect, the present application provides a fireproof cable, which adopts the following technical scheme:

the fireproof cable comprises a conductive core layer and an outer sheath layer, wherein the outer sheath layer is prepared from the following raw materials in parts by weight: 90-100 parts of polyethylene resin, 80-90 parts of fluoroether rubber, 20-30 parts of hydrogenated nitrile rubber, 10-20 parts of superfine spherical alumina, 10-20 parts of polycarbonate polyurethane, 10-15 parts of pentabromoethyl benzene and 1.5-3 parts of peroxide crosslinking agent.

By adopting the technical scheme, the polyethylene resin and the peroxide crosslinking agent are added together, and carbon-carbon crosslinking is generated under the action of heat to form a net structure, so that the corrosion resistance of the polyethylene is improved, the insulativity of the fireproof cable is improved, the electric shock of a contact conductor is prevented, and the service life of the fireproof cable is prolonged. The fluoroether rubber has better corrosion resistance, can keep good low-temperature resistance, has good chemical corrosion resistance while having the characteristics of high strength, oil resistance and wear resistance, and is synergistic with the fluoroether rubber in the aspect of corrosion resistance to improve the comprehensive corrosion resistance of the fireproof cable. The superfine spherical alumina is a corrosion-resistant inert compound, can avoid caking in the processing and using process, and has higher dispersibility in the fireproof cable raw material, thereby enhancing the corrosion resistance of the superfine spherical alumina in the fireproof cable. On one hand, the polycarbonate polyurethane is added as a flame retardant, so that the fireproof cable has a flame retardant effect; on the other hand, the acid and alkali resistance of the fireproof cable can be improved. The pentabromoethyl benzene improves the intermiscibility of the raw materials of the fireproof cable and promotes the raw materials to be uniformly mixed.

Preferably, the method comprises the following steps: a fireproof cable is prepared from the following raw materials in parts by weight: 93-98 parts of polyethylene resin, 82-88 parts of fluoroether rubber, 23-28 parts of hydrogenated nitrile rubber, 12.5-17.5 parts of superfine spherical alumina, 14-18 parts of polycarbonate polyurethane, 10-15 parts of pentabromoethyl benzene and 1.5-3 parts of peroxide cross-linking agent.

Preferably, the method comprises the following steps: the outer sheath layer also comprises the following raw materials in parts by weight: 15-20 parts of nano barite, 20-45 parts of hydrated silicon dioxide and 8-10 parts of silane coupling agent.

By adopting the technical scheme, the nano barite has higher corrosion resistance, and the hydrated silicon dioxide can be used as a reinforcing agent of the fireproof cable and can also be subjected to oleophylic modification, so that the dispersibility of the nano barite in the raw materials of the fireproof cable is improved. The addition of the silane coupling agent improves the dispersibility of the raw materials of the fireproof cable in the system, thereby improving the corrosion resistance of the fireproof cable.

Preferably, the method comprises the following steps: the weight ratio of the nano barite to the hydrated silicon dioxide is 1: (1.5-2.5).

By adopting the technical scheme, the weight part ratio of the nano barite and the hydrated silicon dioxide has great influence on the dispersibility of the nano barite in a fireproof cable raw material system and the strength and wear resistance of the fireproof cable.

Preferably, the method comprises the following steps: the outer sheath layer also comprises the following raw materials in parts by weight: 3-12 parts of diethyl aluminum phosphate.

By adopting the technical scheme, diethyl aluminum phosphate is added as an auxiliary flame retardant to polycarbonate polyurethane, so that the flame retardant effect and the corrosion prevention effect of the polycarbonate polyurethane in the fireproof cable can be improved.

Preferably, the method comprises the following steps: the weight ratio of diethyl aluminum phosphate to polycarbonate polyurethane is 1: (2-4).

Preferably, the method comprises the following steps: the peroxide crosslinking agent is cumene hydroperoxide.

By adopting the technical scheme: when the cumene hydroperoxide is used as a cross-linking agent, a polyethylene product has higher elongation, tensile strength and wear resistance, the polyethylene product is decomposed to generate free radicals, and the free radicals initiate macromolecular radical chain reaction, so that carbon-carbon bond cross-linking of macromolecular compound chains is caused to form a net structure, and the wear resistance, flame retardance and corrosion resistance of the fireproof cable are improved.

Preferably, the method comprises the following steps: the weight ratio of the peroxide crosslinking agent to the polyethylene is 1: (40-50).

In a second aspect, the present application provides a method for preparing any one of the above fireproof cables, which is specifically implemented by the following technical scheme:

a preparation method of a fireproof cable comprises the following operation steps:

melting and mixing polyethylene resin, fluoroether rubber and hydrogenated nitrile rubber to obtain a mixture A;

adding the rest raw materials into the mixture A, and uniformly mixing the raw materials by ultrasonic treatment to obtain a mixture B;

and extruding and molding the mixture B, cooling to obtain an outer sheath layer, and wrapping the outer sheath layer on the periphery of the conductive core layer to obtain the fireproof cable.

In summary, the present application includes at least one of the following beneficial technical effects:

(1) the tensile strength change rates and the elongation at break change rates of the oxalic acid resistance and the sodium hydroxide resistance of the fireproof cables of examples 26 to 40 in the application are superior to those of the fireproof cables of comparative examples 1 to 4, the tensile strength change rates of the oxalic acid resistance and the sodium hydroxide resistance of examples 1 to 40 are respectively-4.2% and-3.4% at the lowest, and the elongation at break change rates of the oxalic acid resistance and the sodium hydroxide resistance of examples 1 to 40 are respectively 13.2% and 12.5% at the highest, so that the fireproof cables show excellent corrosion resistance.

(2) The elongation at break of the fireproof cables of examples 1 to 40 after aging is 162% at most, the oxygen index and the combustion performance are 35.7% at most and B1 at most, respectively, and the fireproof cables are flame-retardant materials and have excellent flame retardance.

Detailed Description

The present application will be described in further detail with reference to specific examples.

The following raw materials are all commercially available products, and are all fully disclosed, and should not be understood as limiting the sources of the raw materials, and specifically: the fluoroether rubber is selected from Vioho plastic factories of Yuyao city, and the content of effective substances is 99.9%; the hydrogenated nitrile rubber is selected from Dajia trade company, Inc. of Guangzhou city; the superfine spherical alumina is selected from New Material science and technology Limited company of hong Kong Wawa, Ling, with particle size of 5 μm; the polycarbonate polyurethane is selected from Youtou plastic science and technology limited of Dongguan city, and the model is 786S; the nano barite is selected from a Living county Hengxin mineral product processing factory, and the particle size is 800 meshes; the silane coupling agent is selected from Nanjing warp-weft chemical Co., Ltd, the content of active substances is 98%, and the type is KH-590.

Example 1

The fireproof cable is prepared by the following method:

according to the mixing amount shown in the table 1, the polyethylene resin, the fluoroether rubber and the hydrogenated nitrile rubber are melted and mixed at the temperature of 130 ℃ to obtain a mixture A;

adding superfine spherical alumina, polycarbonate polyurethane, pentabromoethylbenzene and cumene hydroperoxide into the mixture A, and treating the mixture A by ultrasonic waves to uniformly mix the mixture A and the polycarbonate polyurethane, the pentabromoethylbenzene and the cumene hydroperoxide to obtain a mixture B;

Examples 2 to 5

The fireproof cables of examples 2 to 5 were prepared in the same manner and using the same types of raw materials as those of example 1, except that the amounts of the raw materials were different, as shown in table 1.

TABLE 1 blending amounts (unit: kg) of respective materials of the fireproof cables of examples 1 to 5

Examples 6 to 10

The fireproof cables of examples 6 to 10 were prepared in the same manner and with the same types of raw materials as those of example 3, except that the amounts of the raw materials were different, as shown in table 2.

TABLE 2 blending amounts (unit: kg) of respective materials of the fireproof cables of examples 6 to 10

Raw materials	Example 6	Example 7	Example 8	Example 9	Example 10
						Polyethylene resin	96	96	96	96	96
Fluoroether rubber	80	82	86	88	90
						Hydrogenated nitrile rubber	26	26	26	26	26
Superfine spherical alumina	15	15	15	15	15
						Polycarbonate polyurethane	15	15	15	15	15
Pentabromoethyl benzene	13	13	13	13	13
						Cumene hydroperoxide	2	2	2	2	2

Examples 11 to 15

The fireproof cables of examples 11 to 15 were prepared in the same manner and using the same types of raw materials as those of example 8, except that the amounts of the raw materials were different, as shown in table 3.

TABLE 3 blending amounts (unit: kg) of respective materials of the fireproof cables of examples 11 to 15

Raw materials	Example 11	Example 12	Example 13	Example 14	Example 15
						Polyethylene resin	96	96	96	96	96
Fluoroether rubber	86	86	86	86	86
						Hydrogenated nitrile rubber	20	23	25	28	30
Superfine spherical alumina	15	15	15	15	15
						Polycarbonate polyurethane	15	15	15	15	15
Pentabromoethyl benzene	13	13	13	13	13
						Cumene hydroperoxide	2	2	2	2	2

Examples 16 to 20

The fireproof cables of examples 16 to 20 were prepared in the same manner and with the same types of raw materials as those of example 13, except that the amounts of the raw materials were different, as shown in table 4.

TABLE 4 blending amounts (unit: kg) of respective materials for the fireproof cables of examples 16 to 20

Raw materials	Example 16	Example 17	Example 18	Example 19	Example 20
						Polyethylene resin	90	93	95	98	100
Fluoroether rubber	86	86	86	86	86
						Hydrogenated nitrile rubber	25	25	25	25	25
Superfine spherical alumina	15	15	15	15	15
						Polycarbonate polyurethane	10	14	16	18	20
Pentabromoethyl benzene	10	11	12	14	15
						Cumene hydroperoxide	1.5	1.8	2.3	2.6	3.0

Example 21

The fireproof cable is prepared by the following method:

according to the mixing amount shown in the table 5, the polyethylene resin, the fluoroether rubber and the hydrogenated nitrile rubber are melted and mixed at the temperature of 130 ℃ to obtain a mixture A;

adding superfine spherical alumina, polycarbonate polyurethane, pentabromoethylbenzene, cumene hydroperoxide, nano-barite, hydrated silicon dioxide and a silane coupling agent into the mixture A, and treating by ultrasonic waves to uniformly mix the materials to obtain a mixture B;

Examples 22 to 25

The fireproof cables of examples 22 to 25 were prepared in the same manner and in the same types as those of example 21, except that the amounts of the respective raw materials were different, as shown in table 5.

TABLE 5 blending amounts (unit: kg) of respective materials for the fireproof cables of examples 21 to 25

Example 26

The fireproof cable is prepared by the following method:

according to the mixing amount shown in the table 6, the polyethylene resin, the fluoroether rubber and the hydrogenated nitrile rubber are melted and mixed at the temperature of 130 ℃ to obtain a mixture A;

adding superfine spherical alumina, polycarbonate polyurethane, pentabromoethylbenzene, cumene hydroperoxide, nano-barite, hydrated silicon dioxide, a silane coupling agent and diethyl aluminum phosphate into the mixture A, and treating by ultrasonic waves to uniformly mix the materials to obtain a mixture B;

Examples 27 to 30

The fireproof cables of examples 27 to 30 were prepared in the same manner and using the same types of raw materials as those of example 26, except that the amounts of the raw materials were different, as shown in table 6.

TABLE 6 blending amounts (unit: kg) of respective materials for the fireproof cables of examples 26 to 30

Raw materials	Example 26	Example 27	Example 28	Example 29	Example 30
						Polyethylene resin	95	95	95	95	95
Fluoroether rubber	86	86	86	86	86
						Hydrogenated nitrile rubber	25	25	25	25	25
Superfine spherical alumina	15	15	15	15	15
						Polycarbonate polyurethane	16	18	20	12	15
Pentabromoethyl benzene	12	12	12	12	12
						Cumene hydroperoxide	2.3	2.3	2.3	2.3	2.3
Nano barite	18	18	18	18	18
						Hydrated silica	35	35	35	35	35
Silane coupling agent	9	9	9	9	9
						Aluminium diethyl phosphate	8	6	5	12	3

Examples 31 to 35

The fireproof cables of examples 31 to 35 were prepared in the same manner and in the same types as those of example 27, except that the amounts of the respective raw materials were different, as shown in table 7.

TABLE 7 blending amounts (unit: kg) of respective materials for the flameproof cables of examples 31 to 35

Raw materials	Example 31	Example 32	Example 33	Example 34	Example 35
						Polyethylene resin	95	95	95	95	95
Fluoroether rubber	86	86	86	86	86
						Hydrogenated nitrile rubber	25	25	25	25	25
Superfine spherical alumina	15	15	15	15	15
						Polycarbonate polyurethane	18	18	18	18	18
Pentabromoethyl benzene	12	12	12	12	12
						Cumene hydroperoxide	2.3	2.3	2.3	2.3	2.3
Nano barite	20	19	17	20	15
						Hydrated silica	30	28.5	42.5	20	45
Silane coupling agent	9	9	9	9	9
						Aluminium diethyl phosphate	6	6	6	6	6

Examples 36 to 40

The fireproof cables of examples 36 to 40 were prepared in the same manner and using the same types of raw materials as those of example 32, except that the amounts of the raw materials were different, as shown in table 8.

TABLE 8 blending amounts (unit: kg) of respective materials for the fire-resistant cables of examples 36 to 40

Raw materials	Example 36	Example 37	Example 38	Example 39	Example 40
						Polyethylene resin	96	99	100	98	93.5
Fluoroether rubber	86	86	86	86	86
						Hydrogenated nitrile rubber	25	25	25	25	25
Superfine spherical alumina	15	15	15	15	15
						Polycarbonate polyurethane	18	18	18	18	18
Pentabromoethyl benzene	12	12	12	12	12
						Cumene hydroperoxide	2.4	2.2	2	2.8	1.7
Nano barite	19	19	19	19	19
						Hydrated silica	28.5	28.5	28.5	28.5	28.5
Silane coupling agent	8.8	8.8	8.8	8.8	8.8
						Aluminium diethyl phosphate	6	6	6	6	6

Comparative example 1

The fire-resistant cable of comparative example 1 was prepared exactly the same as in example 1, except that: the equivalent amount of the fluoroether rubber in the raw materials of the fireproof cable is replaced by butyl rubber, and the other raw materials and the mixing amount are the same as those in the example 1.

Comparative example 2

The fire-resistant cable of comparative example 2 was prepared exactly as in example 1, with the following differences: the hydrogenated nitrile rubber in the fireproof cable raw material is replaced by styrene butadiene rubber in an equivalent manner, and the rest raw materials and the mixing amount are the same as those in the example 1.

Comparative example 3

The fire-resistant cable of comparative example 3 was prepared exactly as in example 1, with the following differences: the superfine spherical alumina is not added in the fireproof cable raw materials, and the other raw materials and the mixing amount are the same as those in the embodiment 1.

Comparative example 4

The fire-resistant cable of comparative example 4 was prepared exactly the same as in example 26, except that: the nano barite is not added in the fireproof cable raw material, and the other raw materials and the mixing amount are the same as those in the example 26.

Performance detection

Corrosion resistance: referring to IEC60811, the fireproof cables of examples 1-40 and comparative examples 1-4 were immersed in oxalic acid solution and sodium hydroxide solution respectively for oxalic acid resistance and sodium hydroxide resistance tests, the effective concentrations of the oxalic acid solution and the sodium hydroxide solution were 45g/L and 40g/L respectively, the cables were immersed at 23 + -2 ℃ for 7d, and the tensile strength change rate and the elongation at break change rate were calculated, as shown in Table 9.

Elongation at break after aging: the fireproof cables of examples 1 to 40 and comparative examples 1 to 4 were tested with reference to GB/T2951 general test method for insulation and sheathing materials for electric wires and cables, and the elongation at break after aging was calculated, taking the minimum median value, and the calculation results are shown in Table 9.

Combustion performance: the outer sheath layer materials of the fireproof cables of examples 1-40 and comparative examples 1-4 were subjected to a combustion performance test with reference to GB 8624-1997 ' method for grading combustion performance of construction materials ' for flame performance of wire and cable sheath type plastic materials ' in 6.3, and the oxygen index and the combustion performance grade of the outer sheath layer were tested, and the test results are detailed in Table 9.

TABLE 9 Performance test results for different fireproof cables

The test results in table 9 show that the tensile strength change rates and elongation at break change rates of oxalic acid resistance and sodium hydroxide resistance of the fire-resistant cables of examples 26 to 40 in the present application are superior to those of the fire-resistant cables of comparative examples 1 to 4, and the tensile strength change rates of oxalic acid resistance and sodium hydroxide resistance of examples 1 to 40 are-4.2% and-3.4% at the lowest, and the elongation at break change rates of 13.2% and 12.5% at the highest, respectively, to exhibit superior corrosion resistance. Meanwhile, the elongation at break of the fireproof cables of examples 1 to 40 after aging was as high as 162%, and the oxygen index and flammability rating were 35.7% and B1, respectively, both of which are flame-retardant materials and have strong flame retardancy.

In examples 1-5, the tensile strength change rate and elongation at break of oxalic acid resistance of the fireproof cable of example 3 were-6.5% and 10.9%, respectively, and the tensile strength change rate and elongation at break of sodium hydroxide resistance were-5.7% and 10.4%, respectively, which are superior to those of the fireproof cables of examples 1-2 and examples 4-5; the elongation at break and the oxygen index of the fireproof cable in example 3 after aging are 145% and 33.2%, respectively, which are not lower than those of the fireproof cables in examples 1-2 and 4-5, which shows that the weight parts of the ultrafine spherical alumina in the raw materials of the fireproof cable in example 3 are more suitable, the fireproof cable shows better corrosion resistance and flame retardance, and the fireproof cable has obvious effect of improving the corrosion resistance.

In examples 6-10, the tensile strength change rate and elongation at break of oxalic acid resistance of the fireproof cable of example 8 were-6.2% and 11.2%, respectively, and the tensile strength change rate and elongation at break of sodium hydroxide resistance were-5.4% and 10.7%, respectively, which are superior to those of the fireproof cables of examples 6-7 and examples 9-10; the elongation at break and the oxygen index after aging of the fireproof cable in example 8 are 148% and 33.6%, respectively, which are higher than those of the fireproof cables in examples 6 to 7 and examples 9 to 10, indicating that the parts by weight of the fluoroether rubber in the raw materials of the fireproof cable in example 8 are more suitable, and the fireproof cable in example 8 has better corrosion resistance and flame retardance.

In examples 11-15, the tensile strength change and elongation at break of oxalic acid for the fire-resistant cable of example 13 were-5.9% and 11.5%, respectively, and the tensile strength change and elongation at break of sodium hydroxide were-5.1% and 11.0%, respectively, both superior to the fire-resistant cables of examples 11-12 and examples 14-15; the elongation at break and the oxygen index after aging of the fireproof cable in example 13 are 150% and 33.8% respectively, which are higher than those of the fireproof cables in examples 11 to 12 and examples 14 to 15, and show that the hydrogenated nitrile rubber in the raw materials of the fireproof cable in example 8 is more appropriate in parts by weight, shows better corrosion resistance and flame retardance, and is more obvious in improving the corrosion resistance of the fireproof cable.

In examples 16-20, the tensile strength change and elongation at break of oxalic acid for the fire-resistant cable of example 18 were-5.7% and 11.6%, respectively, and the tensile strength change and elongation at break of sodium hydroxide were-4.9% and 11.2%, respectively, both superior to the fire-resistant cables of examples 16-17 and examples 19-20; the elongation at break and the oxygen index after aging of the fireproof cable in example 18 are 152% and 34.1% respectively, which are higher than those of the fireproof cables in examples 16 to 17 and examples 19 to 20, indicating that the raw materials of the fireproof cable in example 18 are more suitable in parts by weight and show better corrosion resistance and flame retardance, but the corrosion resistance and flame retardance of the fireproof cable in example 18 are not much different from those of the fireproof cable in example 13, indicating that the corrosion resistance and flame retardance of the fireproof cable are less affected by the amount of other components.

In examples 21-25, the tensile strength change and elongation at break of oxalic acid for the fire-resistant cable of example 24 were-5.1% and 12.3%, respectively, and the tensile strength change and elongation at break for the sodium hydroxide were-4.4% and 11.6%, respectively, both superior to the fire-resistant cables of examples 21-23 and example 25; the elongation at break and the oxygen index after aging of the fireproof cable in example 24 are 154% and 34.2%, respectively, which are not lower than those of the fireproof cables in examples 21 to 23 and 25, which shows that the nano barite and the silane coupling agent in the raw materials of the fireproof cable in example 24 are more appropriate in parts by weight, show better corrosion resistance and flame retardance, and are more obvious in improving the corrosion resistance of the fireproof cable.

In examples 26-30, the tensile strength change and elongation at break of oxalic acid for the fire-resistant cable of example 27 were-4.9% and 12.5%, respectively, and the tensile strength change and elongation at break of sodium hydroxide were-4.1% and 11.8%, respectively, both superior to the fire-resistant cables of examples 26 and 28-29; the elongation at break and the oxygen index after aging of the fireproof cable in example 27 are 156% and 34.7%, respectively, which are higher than those of the fireproof cables in examples 26 and 28 to 29, and it is shown that the raw materials of the fireproof cable in example 27 are more suitable when the weight ratio of the diethyl aluminum phosphate to the polycarbonate polyurethane is 1:3, and show better corrosion resistance and flame retardancy, and are more obvious in improving the flame retardancy of the fireproof cable.

In examples 31-35, the tensile strength change and elongation at break of oxalic acid for the fire-resistant cable of example 32 were-4.4% and 13.0%, respectively, and the tensile strength change and elongation at break of sodium hydroxide were-3.6% and 12.3%, respectively, both superior to the fire-resistant cables of examples 31 and 33-34; the elongation at break and the oxygen index of the fireproof cable in example 32 after aging are 159% and 34.8%, respectively, which are not lower than those of the fireproof cables in examples 31 and 33-34, and the results show that the raw materials of the fireproof cable in example 32 are more suitable when the weight ratio of the nano barite to the hydrated silicon dioxide is 1:2, so that the fireproof cable has excellent corrosion resistance and flame retardance, and is obvious in improving the corrosion resistance of the fireproof cable.

In examples 36-40, the tensile strength change and elongation at break of oxalic acid for example 37 were-4.2% and 13.2%, respectively, and the tensile strength change and elongation at break for sodium hydroxide were-3.4% and 12.5%, respectively, which are superior to those of the fire-resistant cables of examples 36 and 38-39; the elongation at break and the oxygen index after aging of the fireproof cable in example 37 are 162% and 35.7%, respectively, which are higher than those of the fireproof cables in examples 36 and 38-39, and show that the raw materials of the fireproof cable in example 37 are more suitable when the weight ratio of the peroxide crosslinking agent to the polyethylene resin is 1:45, so that the fireproof cable has better corrosion resistance and flame retardance, and the fireproof cable has more remarkable improvement in flame retardance.

In addition, from the index data of comparative example 26 and comparative examples 1-4, it is found that the addition of fluoroether rubber, hydrogenated nitrile rubber, ultrafine spherical alumina and nano barite selected from the raw materials of the present application improves the corrosion resistance and flame retardancy of the fireproof cable to various degrees.

The present embodiment is only for explaining the present application, and it is not limited to the present application, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present application.

Claims

1. The fireproof cable is characterized by comprising a conductive core layer and an outer sheath layer, wherein the outer sheath layer is prepared from the following raw materials in parts by weight: 90-100 parts of polyethylene resin, 80-90 parts of fluoroether rubber, 20-30 parts of hydrogenated nitrile rubber, 10-20 parts of superfine spherical alumina, 10-20 parts of polycarbonate polyurethane, 10-15 parts of pentabromoethyl benzene and 1.5-3 parts of peroxide crosslinking agent.

2. The fireproof cable of claim 1, wherein the fireproof cable is prepared from the following raw materials in parts by weight: 93-98 parts of polyethylene resin, 82-88 parts of fluoroether rubber, 23-28 parts of hydrogenated nitrile rubber, 12.5-17.5 parts of superfine spherical alumina, 14-18 parts of polycarbonate polyurethane, 10-15 parts of pentabromoethyl benzene and 1.5-3 parts of peroxide cross-linking agent.

3. The fireproof cable of claim 1, wherein the outer jacket layer further comprises the following raw materials in parts by weight: 15-20 parts of nano barite, 20-45 parts of hydrated silicon dioxide and 8-10 parts of silane coupling agent.

4. A fire-resistant cable according to claim 3, wherein: the weight ratio of the nano barite to the hydrated silicon dioxide is 1: (1.5-2.5).

5. The fire-protected cable of claim 1, wherein: the outer sheath layer also comprises the following raw materials in parts by weight: 3-12 parts of diethyl aluminum phosphate.

6. The fire-protected cable of claim 5, wherein: the weight ratio of diethyl aluminum phosphate to polycarbonate polyurethane is 1: (2-4).

7. The fire-protected cable of claim 1, wherein: the peroxide crosslinking agent is cumene hydroperoxide.

8. The fire-protected cable of claim 1, wherein: the weight ratio of the peroxide crosslinking agent to the polyethylene resin is 1: (40-50).

9. A method for preparing a fire-resistant cable according to any one of claims 1 to 8, characterized in that it comprises the following operative steps: