WO2021129217A1 - Low-smoke and halogen-free building wire and cable material, and preparation method therefor - Google Patents

Abstract

Disclosed are a building wire and cable material, and a preparation method therefor. Raw materials for preparing the building wire and cable material comprise, by weight percentage, 10-30% of a linear low-density polyethylene, 5-20% of a thermoplastic elastomer, 0.5-10% of ethylene-propylene-diene monomer, 5-10% of a maleic-anhydride-grafted EVA, 30-40% of aluminum hydroxide and 2-10% of a modified aluminum hypophosphite. The preparation method comprises the following steps: (1) weighing formulation amounts of the above-mentioned raw materials, performing mixing, and then performing internal mixing, melt blending and extrustion to obtain blended particles; and (2) manufacturing the blended particles into a wire, and then subjecting the wire to irradiation crosslinking to obtain a building wire and cable material.

Description

Low-smoke halogen-free building wire cable material and preparation method thereof Technical field

The application belongs to the field of cable insulation materials, and relates to a building wire cable material and a preparation method thereof, and in particular to a high-elasticity, low-smoke, halogen-free building wire cable material and a preparation method thereof.

Background technique

With the rapid development of my country's economy, all walks of life are developing rapidly, and all aspects of industry, agriculture, and life involve the use of electricity, so wires and cables are indispensable. Traditional cloth wires are inexpensive, but over time, whether it is PVC wiring or polyethylene (PE) wiring, the materials will become hard and brittle, and aging wires can easily cause sudden circuit short circuits. Cause a lot of fire accidents.

Around the 1970s, a series of serious fire accidents occurred in the United States, Japan, and Western European countries, the establishment of Suzihe nuclear power plants, the large-scale modern factories, the high-rise and densification of urban buildings, and the popularization of electronic computing control centers and household appliances. , The increasing number of electrical fire accidents has aroused the attention of countries all over the world. In 1975, the Brown Ferry nuclear power plant in the United States caught fire due to the interlayer through which the cables passed. The bundles of cables were laid on fire, which caused a fire. 1,700 cables were burned, and the loss amounted to 100 million US dollars. Taiwan telephone exchange was scrapped and lost 59 million US dollars. According to Japanese statistics, there were an average of 199 fire accidents per day in 1975, with a loss of 250 million yuan.

The working temperature of the existing ordinary cloth wires in China is usually between 70-90°C. Although the maximum working temperature of cross-linked polyolefin insulated wires can reach 150°C, they have no good fire resistance or fire resistance. The indoor cloth wires currently used in my country's construction industry are mainly polyvinyl chloride insulated wires. Its advantages are: light weight, low price, good electrical insulation and certain flame retardancy, so it is welcomed by consumers. However, there are hidden safety hazards in the use of PVC insulated wires. When a fire accident occurs, a large amount of smoke generated by the burning of the wire and the released halogen acid gas will seriously affect the firefighting of firefighters and endanger their lives. , Resulting in the so-called "second disaster", at the same time, the corrosive halogen acid gas will also corrode furniture and household appliances.

Compared with indoor wiring, construction wire cables are installed outdoors most of the time, and there is more friction with buildings. Therefore, the mechanical properties and flame retardant properties of construction wire cables are more stringent. Today, people's awareness of environmental protection is increasing, high-rise buildings and densely populated public places have banned the use of PVC insulated wires. Instead, they will be flame-retardant and halogen-free environmentally friendly cables.

In addition to formulating and modifying safety and fire protection regulations, improving flame retardant requirements and establishing corresponding flame retardant fire protection measures, the prevention of fires must also focus on solving the following problems: how to improve the flame retardancy of cables under compound conditions, and how to improve The flame retardancy of cables laid in bundles in tunnels and how to limit the amount of smoke generated by the cables and the release of harmful gases such as hydrogen chloride during a fire.

CN106832610A discloses a low-cost tear-resistant high-rise building power cable rubber compound. Its raw materials include, by weight, 40-80 parts of EPDM, 15-35 parts of nitrile rubber, and 20-40 parts of styrene butadiene rubber. 5-15 parts of carbon fiber, 10-20 parts of fly ash, 4-16 parts of medical stone, 20-30 parts of zeolite powder, 2-4 parts of sulfur, 2-5 parts of compound plasticizer, 1-1.8 parts of accelerator , 1-2 parts of antioxidant, 1-2 parts of anti-aging agent, 1-2 parts of lubricant, etc. This application has good tear resistance, excellent waterproof and aging resistance, and does not contain halogen. It is suitable for the requirements of high-rise buildings for power cables. However, the power cables made of this rubber material have poor flame retardancy.

Therefore, it is of great significance to increase the research and development of building wire cables, and to develop and produce a low-smoke, halogen-free, environmentally friendly building wire cable with high physical properties and high flame retardancy.

Summary of the invention

The purpose of this application is to provide a building wire cable material and a preparation method thereof. The building wire and cable material has high elongation, good elasticity, and good flame retardancy, which meets the requirements of the building wire and cable for physical properties and flame retardancy. At the same time, the material does not contain halogen and emits smoke when burned. The amount is small. To achieve this goal, this application adopts the following technical solutions:

In the first aspect, the present application provides a construction wire and cable material, the preparation raw materials of the construction wire and cable material include the following components by weight percentage:

In this application, aluminum hypophosphite has the advantages of halogen-free, non-toxic, low-smoke, etc. It can be used in conjunction with aluminum hydroxide to improve the flame retardancy of the material; at the same time, during the heating process, a carbon foam layer can be formed to protect the polymer Function, heat insulation and oxygen insulation, the smoke density and toxic gas during combustion can be greatly reduced, and no hydrogen halide gas is generated; aluminum hydroxide is low in cost, and can produce a lot of water vapor when heated and decomposed, and has a certain flame retardant effect, but when added in large amounts Will reduce the mechanical properties of the material.

In this application, linear low-density polyethylene and thermoplastic elastomer are used as matrix materials, aluminum hydroxide and modified aluminum hypophosphite are added, and the amount of aluminum hydroxide is small, the elongation of the obtained material is higher, and the mechanical properties are better. At the same time, the flame retardancy of the material has not been reduced due to the decrease in the amount of aluminum hydroxide. Therefore, the reasonable ratio of aluminum hydroxide and modified aluminum hypophosphite in the present application results in a higher elongation and flame retardancy. Better high-elasticity, low-smoke, halogen-free building wire and cable material.

Wherein, the content of the linear low-density polyethylene can be 10%, 12%, 15%, 18%, 20%, 22%, 25%, 26%, 28%, 30%, etc., by weight percentage. The content of elastomer can be 5%, 6%, 8%, 10%, 11%, 12%, 14%, 15%, 18% or 20%, etc. The content of EPDM can be 0.5%, 1 %, 2%, 3%, 5%, 6%, 7%, 8%, 9% or 10%, etc., the content of maleic anhydride grafted EVA (ethylene-vinyl acetate copolymer) can be 5%, 5.5% , 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9% or 10%, etc. The content of aluminum hydroxide can be 30%, 31%, 32%, 33%, 34%, 35% , 36%, 37%, 38%, 39% or 40%, etc. The content of modified aluminum hypophosphite can be 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% or 10% etc.

As an optional technical solution of the present application, the particle size of the aluminum hydroxide is 1-2 μm, for example, it can be 1 μm, 1.2 μm, 1.4 μm, 1.5 μm, 1.6 μm, 1.8 μm, 1.9 μm, or 2 μm.

Optionally, the modified aluminum hypophosphite is aluminum hypophosphite modified with a silane coupling agent.

Optionally, the mass ratio of aluminum hydroxide to aluminum hypophosphite is (5-20):1, for example, 5:1, 6:1, 8:1, 10:1, 12:1, and 14: 1, 16:1, 18:1 or 20:1, etc.

Optionally, the linear low-density polyethylene has a molecular weight of 100,000 to 150,000, for example, 100,000, 105,000, 110,000, 115,000, 120,000, 130,000, 140,000, or 150,000, etc., and the melt index It is 1-5 g/10min, for example, it may be 1g/10min, 1.5g/10min, 2g/10min, 2.5g/10min, 3g/10min, 3.5g/10min, 4g/10min, 5g/10min, or the like.

Optionally, the thermoplastic elastomer is an ethylene-octene copolymer.

Optionally, the Shore A hardness of the ethylene-octene copolymer is 80-90, for example, it can be 80, 82, 84, 86, 88, or 90, etc., and the melt index is 2-4g/10min, for example, it can be 2g/10min, 2.2g/10min, 2.3g/10min, 2.5g/10min, 3g/10min, 3.2g/10min, 3.6g/10min or 4g/10min, etc.

As an optional technical solution of this application, the grafting rate of the maleic anhydride grafted EVA is 1-3%, for example, it can be 1%, 1.2%, 1.3%, 1.5%, 1.8%, 2%, 2.2% , 2.4%, 2.6% or 3%, etc.

Optionally, the mass percentage of vinyl acetate in the maleic anhydride grafted EVA is 30-35%, for example, it can be 30%, 30.5%, 31%, 31.5%, 32%, 32.5%, 33%. , 33.5%, 34%, 34.5% or 35% etc.

Maleic anhydride grafted EVA is used for halogen-free flame-retardant filler-filled composite cable materials such as aluminum hydroxide and magnesium hydroxide, which can improve the compatibility and adhesion between the polyolefin matrix and the inorganic flame-retardant interface, thereby maximizing The flame retardancy of the cable material can reduce the smoke index, smoke generation, heat generation and carbon monoxide production, increase the oxygen index, improve the dripping performance, etc., and significantly improve the mechanical and thermal properties of the material.

Optionally, the synthetic monomers of the EPDM rubber are ethylene, propylene and ethylidene norbornene. In the production of EPDM rubber, its characteristics can be adjusted by changing the number of monomers, the ratio of ethylene to propylene, the molecular weight and its distribution, and the method of vulcanization.

Optionally, the mass percentage of ethylidene norbornene in the synthetic monomer of the EPDM rubber is 1-3%, for example, it can be 1%, 1.2%, 1.3%, 1.5%, 1.8%, 2%, 2.2%, 2.4%, 2.6% or 3% etc.

Optionally, the molecular weight of the EPDM rubber is 50,000 to 150,000, for example, it can be 50,000, 60,000, 70,000, 80,000, 100,000, 120,000, 140,000 or 150,000, etc., Shore A The hardness is 20-50, for example, it can be 20, 25, 30, 35, 40, 45, or 50.

Optionally, the preparation raw materials of the building wire and cable material also include a weight percentage of 1-3% (for example, it can be 1%, 1.2%, 1.5%, 1.8%, 2%, 2.2%, 2.5%, 2.6% or 3% etc.) of the stabilizer.

Optionally, the stabilizer comprises 30-55% (for example, 30%, 35%, 40%, 45%, 50% or 55%, etc.) of calcium stearate, 5-35% by weight. (For example, it can be 5%, 10%, 15%, 20%, 25%, 30% or 35%, etc.) of zinc stearate and 30-60% (for example, it can be 30%, 35%, 40%, 45 %, 50%, 55%, 60%, etc.) tetra[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] pentaerythritol ester.

As an optional technical solution of the present application, the raw materials for the preparation of the building wire and cable material also include a weight percentage of 1-3% (for example, it can be 1%, 1.2%, 1.5%, 1.8%, 2%, 2.2%, 2.5%). %, 2.6% or 3% etc.) of silicone masterbatch.

Optionally, the preparation raw materials of the building wire and cable material also include a weight percentage of 1-2% (for example, it can be 1%, 1.1%, 1.2%, 1.3%, 1.5%, 1.6%, 1.7%, 1.8% or 2% etc.) of antioxidants.

As an optional technical solution of the present application, the preparation raw materials of the building wire and cable material include the following components in terms of weight percentage:

In the second aspect, the present application also provides a method for preparing the building wire and cable material as described in the first aspect, and the preparation method includes the following steps:

(1) Weigh the linear low-density polyethylene, thermoplastic elastomer, EPDM rubber, maleic anhydride grafted EVA, aluminum hydroxide and modified aluminum hypophosphite to mix, and then banbury and melt blend. Extrusion to obtain blended particles;

(2) The blended particles are made into a wire, and then the wire is irradiated and crosslinked to obtain the building wire and cable material.

As an optional technical solution of the present application, the internal mixing and melting in step (1) is performed by an internal mixer.

Optionally, the melting temperature of the internal mixer in step (1) is 160-175°C, for example, it can be 160°C, 162°C, 165°C, 170°C, 172°C or 175°C, etc., and the time is 15-25 min For example, it can be 15min, 16min, 17min, 20min, 21min, 22min, 24min or 25min.

Optionally, the extrusion in step (1) is performed by a single screw extruder.

Optionally, the single-screw extruder includes a first zone, a second zone, a third zone, a fourth zone, a fifth zone, a sixth zone, and a seventh zone connected in sequence.

Optionally, the working temperature of the first zone is 110-115°C (for example, it can be 110°C, 111°C, 112°C, 113°C, 114°C, or 115°C, etc.), and the working temperature of the second zone is 115-115°C. 120°C (for example, 115°C, 116°C, 117°C, 118°C, 119°C or 120°C, etc.), the working temperature of the third zone is 115-120°C (for example, 115°C, 116°C, 117°C, 118°C, 119°C or 120°C, etc.), the working temperature of the fourth zone is 120-125°C (for example, it can be 120°C, 121°C, 122°C, 123°C, 124°C or 125°C, etc.), the fifth zone's working temperature The working temperature is 120-125°C (for example, it can be 120°C, 121°C, 122°C, 123°C, 124°C, or 125°C, etc.). The working temperature of the sixth zone is 120-130°C (for example, it can be 120°C, 122°C, etc.). ℃, 124℃, 126℃, 128℃ or 130℃ etc.), the working temperature of the seventh zone is 125-130℃ (for example, it can be 125℃, 126℃, 127℃, 128℃, 129℃ or 130℃ etc.) .

Optionally, the wire made in step (2) is performed by a wire extruder.

As an optional technical solution of the present application, the wire extruder in step (2) includes a zone A, a zone B, a zone C, and a zone D connected in sequence.

Optionally, the working temperature of the A zone is 110-120°C (for example, it can be 110°C, 112°C, 114°C, 116°C, 118°C or 120°C, etc.), and the working temperature of the B zone is 135-145°C (For example, it can be 135°C, 137°C, 139°C, 140°C, 142°C or 145°C, etc.), the working temperature of zone C is 145-155°C (for example, it can be 145°C, 147°C, 150°C, 151°C, 152°C or 155°C, etc.), the working temperature of zone D is 150-160°C (for example, it can be 150°C, 152°C, 154°C, 156°C, 158°C or 160°C, etc.).

Optionally, the radiation crosslinking is performed by an electron accelerator, and the radiation dose is 8-12 Mrad, for example, it can be 8 Mrad, 8.5 Mrad, 9 Mrad, 9.5 Mrad, 10 Mrad, 11 Mrad or 12 Mrad.

In the third aspect, the present application also provides an application of the building wire cable material as described in the first aspect in the preparation of cables.

The numerical range described in this application not only includes the above-mentioned exemplified point values, but also includes any point value between the above-mentioned numerical ranges that are not exemplified. Due to the limitation of space and for the sake of brevity, this application will not exhaustively list all the points. The specific point value included in the stated range.

Compared with the prior art, the beneficial effects of this application are:

(1) The building wire and cable material provided by this application is a halogen-free and low-smoke environmentally friendly material with high elongation, good mechanical properties, and good flame retardancy, which improves the safety of the cable during use , Which can meet the requirements of high elongation and high flame retardant properties of building wires and cables;

(2) The building wire and cable materials provided by this application can all pass the single vertical burning test, and the tensile strength is ≥11.9MPa, the elongation at break is ≥225%, the smoke density and light transmittance are ≥69%, and the thermal elongation is ≤25%. , 90 degree insulation resistance is higher.

Detailed ways

The technical solutions of the present application will be further explained through specific implementations below. It should be understood by those skilled in the art that the described embodiments are merely to help understand the application and should not be regarded as specific limitations to the application.

The reagents or materials used in the following examples can be purchased from conventional manufacturers, and the specific manufacturers and models are shown in Table 1:

Table 1

name	manufacturer	model
Linear Low Density Polyethylene	ExxonMobil Chemical	3518CB
Thermoplastic elastomer	Hangzhou Jusheng Cable Material Co., Ltd.	TPE404
EPDM rubber	Dow Chemical	EPDM855
Maleic anhydride grafted EVA	Shanghai Jiuju Chemical Technology Co., Ltd.	TM169
Silicone masterbatch	Zhejiang Jiahua Essence Co., Ltd.	GT500
Modified aluminum hypophosphite	Suzhou Lianxiong Fine Chemical Co., Ltd.	HT220
Antioxidant	Hangzhou Jusheng Cable Material Co., Ltd.	AD125
Aluminium hydroxide with a particle size of 2μm	Luoyang Zhongchao New Materials Co., Ltd.	AH-01DG
Aluminium hydroxide with a particle size of 1μm	Luoyang Zhongchao New Materials Co., Ltd.	AH-01

Example 1

To provide a high-elasticity, low-smoke, and halogen-free building wire and cable material, which includes by weight percentage:

28% linear low density polyethylene, 20% thermoplastic elastomer, 8% EPDM rubber, 8% maleic anhydride grafted EVA, 30% aluminum hydroxide and 6% modified aluminum hypophosphite.

Wherein, the linear low-density polyethylene has a molecular weight of 130,000 and a melt index of 3g/10min; the thermoplastic elastomer is an ethylene-octene copolymer with a Shore A hardness of 87 and a melt index of 3.5g/10min; The graft rate of EVA grafted with acid anhydride is 2.1%; the particle size of aluminum hydroxide is 2μm, and the modified aluminum hypophosphite is aluminum hypophosphite modified with silane coupling agent KH-550, and its particle size is 10μm;

The preparation method is:

(1) Weigh the components of the formula, and the mixed materials are melt blended at 160°C for 25 minutes in an internal mixer, and then pelletized by a single-screw extruder. The single-screw extruder includes the first zone, In the second zone, third zone, fourth zone, fifth zone, sixth zone and seventh zone, the material passes through each zone in sequence, and the working temperature of the first zone is set to 110℃, and the working temperature of the second zone is 115℃. The operating temperature in the third zone is 115°C, the operating temperature in the fourth zone is 120°C, the operating temperature in the fifth zone is 120°C, the operating temperature in the sixth zone is 120°C, and the operating temperature in the seventh zone is 125°C;

(2) The pellets prepared by the single-screw extruder are added to the wire extruder, the wire extruder includes the A zone, the B zone, the C zone and the D zone connected in sequence, and the pellets pass through each zone in turn, Set the working temperature of zone A to 110°C, the working temperature of zone B to 135°C, the working temperature of zone C to 145°C, and the working temperature of zone D to 150°C. After the wire is obtained, an electron accelerator is used for irradiation crosslinking. The irradiation dose is 8 Mrad to obtain the high-elasticity, low-smoke, and halogen-free building wire and cable material.

Example 2

To provide a high-elasticity, low-smoke, and halogen-free building wire and cable material, which includes by weight percentage:

25% linear low density polyethylene, 20% thermoplastic elastomer, 8% EPDM rubber, 8% maleic anhydride grafted EVA, 30% aluminum hydroxide, 6% modified aluminum hypophosphite, 1% stabilizer, 1% silicone masterbatch and 1% antioxidant;

The linear low-density polyethylene has a molecular weight of 130,000 and a melt index of 3g/10min; the thermoplastic elastomer is an ethylene-octene copolymer with a Shore A hardness of 87 and a melt index of 3.5g/10min; maleic anhydride The grafting rate of grafted EVA is 2.1%; the particle size of aluminum hydroxide is 1μm, and the modified aluminum hypophosphite is aluminum hypophosphite modified with silane coupling agent KH-550, and its particle size is 10μm;

The stabilizer in this embodiment consists of 50 parts by weight calcium stearate, 10 parts by weight zinc stearate and 40 parts by weight tetra[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] Composition of pentaerythritol ester.

The preparation method is:

(1) Weigh the components of the formula, and the mixed materials are melt-blended at 170°C for 20 minutes in an internal mixer, and then pelletized by a single-screw extruder. The single-screw extruder includes the first connected in sequence. Zone, second zone, third zone, fourth zone, fifth zone, sixth zone and seventh zone, the material passes through each zone in turn, set the working temperature of the first zone to 112℃, and the working temperature of the second zone to 118 ℃, the working temperature of the third zone is 118℃, the working temperature of the fourth zone is 123℃, the working temperature of the fifth zone is 123℃, the working temperature of the sixth zone is 125℃, and the working temperature of the seventh zone is 128 ℃;

(2) The pellets prepared by the single-screw extruder are added to the wire extruder, the wire extruder includes the A zone, the B zone, the C zone and the D zone connected in sequence, and the pellets pass through each zone in turn, Set the working temperature of zone A to 115°C, the working temperature of zone B to 140°C, the working temperature of zone C to 150°C, and the working temperature of zone D to 155°C. After the wire is obtained, an electron accelerator is used for irradiation crosslinking. The irradiation dose is 9 Mrad to obtain the high-elasticity, low-smoke, and halogen-free building wire and cable material.

Example 3

To provide a high-elasticity, low-smoke, and halogen-free building wire and cable material, which includes by weight percentage:

30% linear low density polyethylene, 10% thermoplastic elastomer, 0.5% EPDM rubber, 5.5% maleic anhydride grafted EVA, 38% aluminum hydroxide, 10% modified aluminum hypophosphite, 2% stabilizer, 2% silicone masterbatch and 2% antioxidant;

The preparation method is:

(1) Weigh the components of the formula, and the mixed materials are melt blended at 175°C for 15 minutes in an internal mixer, and then pelletized by a single-screw extruder. The single-screw extruder includes the first Zone, second zone, third zone, fourth zone, fifth zone, sixth zone and seventh zone, the material passes through each zone in turn, set the working temperature of the first zone to 115℃, and the working temperature of the second zone to 120 ℃, the working temperature of the third zone is 120℃, the working temperature of the fourth zone is 125℃, the working temperature of the fifth zone is 125℃, the working temperature of the sixth zone is 130℃, and the working temperature of the seventh zone is 130 ℃;

(2) The pellets prepared by the single-screw extruder are added to the wire extruder, the wire extruder includes the A zone, the B zone, the C zone and the D zone connected in sequence, and the pellets pass through each zone in turn, Set the working temperature of zone A to 120°C, the working temperature of zone B to 145°C, the working temperature of zone C to 155°C, and the working temperature of zone D to 160°C. After the wire is obtained, an electron accelerator is used for irradiation crosslinking. The irradiation dose is 10 Mrad to obtain the high-elasticity, low-smoke, and halogen-free building wire and cable material.

Example 4

To provide a high-elasticity, low-smoke, and halogen-free building wire and cable material, which includes by weight percentage:

15% linear low density polyethylene, 7% thermoplastic elastomer, 10% EPDM rubber, 10% maleic anhydride grafted EVA, 40% aluminum hydroxide, 10% modified aluminum hypophosphite, 3% stabilizer, 2% silicone masterbatch and 2% antioxidant; its preparation method is the same as in Example 2.

Example 5

To provide a high-elasticity, low-smoke, and halogen-free building wire and cable material, which includes by weight percentage:

20% linear low density polyethylene, 20% thermoplastic elastomer, 5% EPDM, 5% maleic anhydride grafted EVA, 40% aluminum hydroxide, 2% modified aluminum hypophosphite, 3% stabilizer, 3% silicone masterbatch and 2% antioxidant; its preparation method is the same as in Example 2.

Comparative example 1

Compared with Example 2, the difference is that this comparative example does not contain modified aluminum hypophosphite, the weight percentage of aluminum hydroxide is increased to 36%, and the remaining components and preparation methods are the same as in Example 2.

Comparative example 2

Compared with Example 2, the difference is that the comparative example does not contain aluminum hydroxide, the weight percentage of modified aluminum hypophosphite is increased to 36%, and the remaining components and preparation methods are the same as in Example 2.

Comparative example 3

Compared with Example 2, the difference is that in this comparative example, aluminum hydroxide is replaced with magnesium hydroxide, and the remaining components and preparation methods are the same as in Example 2.

Comparative example 4

Compared with Example 2, the difference is that in this comparative example, the amount of aluminum hydroxide is increased to 56%, and the contents of the remaining components are 15% linear low-density polyethylene, 10% thermoplastic elastomer, and 5% ternary. Ethylene propylene rubber, 5% maleic anhydride grafted EVA, 6% modified aluminum hypophosphite, 1% stabilizer, 1% silicone masterbatch and 1% antioxidant.

Comparative example 5

Compared with Example 2, the difference is that in this comparative example, the amount of aluminum hydroxide is reduced to 20%, and the contents of the remaining components are 35% linear low-density polyethylene, 26% thermoplastic elastomer, and 5% ternary. Ethylene propylene rubber, 5% maleic anhydride grafted EVA, 6% modified aluminum hypophosphite, 1% stabilizer, 1% silicone masterbatch and 1% antioxidant.

Comparative example 6

In this comparative example, the mass ratio of aluminum hydroxide to modified aluminum hypophosphite is 30:1, and the content of each component in the raw materials is 26% linear low-density polyethylene, 20% thermoplastic elastomer, and 10% ternary. Ethylene propylene rubber, 10% maleic anhydride grafted EVA, 30% aluminum hydroxide, 1% modified aluminum hypophosphite, 1% stabilizer, 1% silicone masterbatch and 1% antioxidant.

Comparative example 7

In this comparative example, the mass ratio of aluminum hydroxide to modified aluminum hypophosphite is 1:1, and the content of each component in the raw materials is 17% linear low-density polyethylene, 10% thermoplastic elastomer, and 10% ternary. Ethylene propylene rubber, 10% maleic anhydride grafted EVA, 25% aluminum hydroxide, 25% modified aluminum hypophosphite, 1% stabilizer, 1% silicone masterbatch and 1% antioxidant.

Performance Testing

The performance of the cable materials provided in the foregoing Examples 1-5 and Comparative Examples 1-7 were tested. The test standards include: (1) Tensile strength and elongation at break: GB/T2951;

(2) Smoke density and light transmittance: GB/T19651-1998;

(3) Thermal extension: GB/T2951.11-2008;

(4) Oxygen index: ISO 4586;

(5) Single vertical burning: GB/T18380-2008;

(6) 90 degree insulation resistance: GB/T12706-2008.

Other properties of the cable materials provided by Examples 1-5 and Comparative Examples 1-7 are shown in Table 2 below:

Table 2

It can be seen from Table 2 that the building wire and cable material provided by the present application has both good flame retardancy and physical properties, and both can pass the single vertical burning test, and the elongation at break is above 225%. The smoke of the obtained material With high density and light transmittance, it is a high-elasticity, low-smoke, and halogen-free cable material suitable for construction lines.

Among them, from the comparison of Example 2, Comparative Examples 1 and 2, it can be seen that if modified aluminum hypophosphite or aluminum hydroxide is not added to the material, the resulting material cannot pass the single vertical burning test, that is, the flame retardancy is poor; 2 Compared with Comparative Example 3, it can be seen that there is a synergistic coordination effect between aluminum hydroxide and modified aluminum hypophosphite. If aluminum hydroxide is replaced with other flame retardants, such as the obtained magnesium hydroxide, the obtained material cannot pass through a single vertical Combustion test, and magnesium hydroxide as a flame retardant will make the material difficult to be processed and affect the product yield; comparison of Example 2 with Comparative Examples 4 and 5 shows that if the content of aluminum hydroxide in the material is higher, the material obtained Although it can pass the single vertical burning test, its physical performance parameters such as tensile strength and elongation at break are poor. If the content of aluminum hydroxide in the material is small, the resulting material has poor flame retardancy; from Example 2 Compared with Comparative Examples 6 and 7, it can be seen that when the ratio of aluminum hydroxide to modified aluminum hypophosphite is 30:1 and 1:1, the flame retardant performance and physical properties cannot meet the standards for building wire materials at the same time, indicating that hydrogen The coordination and synergy between alumina and modified aluminum hypophosphite is not ideal.

In summary, this application adopts a reasonable ratio of aluminum hydroxide and modified aluminum hypophosphite, and the resulting material has better flame retardancy and higher mechanical properties, which meets the market’s requirements for high elasticity and high flame retardancy of building cables Requirements.

The applicant declares that the above are only specific implementations of this application, but the protection scope of this application is not limited to this.

Claims (12)

1. A construction wire and cable material, wherein the preparation raw materials of the construction wire and cable material include the following components in terms of weight percentage:

   
2. The building wire and cable material according to claim 1, wherein the particle size of the aluminum hydroxide is 1-2 μm.
3. The building wire and cable material according to claim 1 or 2, wherein the modified aluminum hypophosphite is aluminum hypophosphite modified with a silane coupling agent.
4. The building wire and cable material according to any one of claims 1 to 3, wherein the mass ratio of the aluminum hydroxide to the modified aluminum hypophosphite is (5-20):1.
5. The building wire and cable material according to any one of claims 1 to 4, wherein the linear low density polyethylene has a molecular weight of 100,000 to 150,000 and a melt index of 1-5 g/10min;

   Optionally, the thermoplastic elastomer is an ethylene-octene copolymer;

   Optionally, the Shore A hardness of the ethylene-octene copolymer is 80-90, and the melt index is 2-4 g/10 min.
6. The building wire and cable material according to any one of claims 1-5, wherein the grafting rate of the maleic anhydride grafted EVA is 1-3%;

   Optionally, the mass percentage of vinyl acetate in the maleic anhydride grafted EVA is 30-35%;

   Optionally, the synthetic monomers of the EPDM rubber are ethylene, propylene and ethylidene norbornene;

   Optionally, the mass percentage of ethylidene norbornene in the synthetic monomer of the ethylene propylene diene rubber is 1-3%;

   Optionally, the molecular weight of the EPDM rubber is 50,000-150,000, and the Shore A hardness is 20-50.
7. The building wire and cable material according to any one of claims 1-6, wherein the raw material for preparing the building wire and cable material further comprises a stabilizer with a weight percentage of 1-3%;

   Optionally, the stabilizer comprises 30-55% calcium stearate, 5-35% zinc stearate and 30-60% four [β-(3,5-di-tert-butyl 4-hydroxyphenyl)propionate] pentaerythritol ester.
8. The building wire and cable material according to any one of claims 1-7, wherein the raw material for preparing the building wire and cable material further comprises 1-3% by weight of silicone masterbatch;

   Optionally, the raw materials for preparing the building wire and cable material further include an antioxidant in a weight percentage of 1-2%.
9. The building wire and cable material according to any one of claims 1-8, wherein the raw materials for preparing the building wire and cable material include the following components in terms of weight percentage:

   

   
10. A method for preparing the building wire and cable material according to any one of claims 1-9, which comprises the following steps:

    (1) Weigh the linear low-density polyethylene, thermoplastic elastomer, EPDM rubber, maleic anhydride grafted EVA, aluminum hydroxide and modified aluminum hypophosphite to mix, and then banbury and melt blend. Extrusion to obtain blended particles;

    (2) The blended particles are made into a wire, and then the wire is irradiated and crosslinked to obtain the building wire and cable material.
11. The preparation method according to claim 10, wherein the banbury melting in step (1) is performed by an internal mixer;

    Optionally, the temperature of the banbury melting in step (1) is 160-175°C, and the time is 15-25 min;

    Optionally, the extrusion in step (1) is performed by a single screw extruder;

    Optionally, the single-screw extruder includes a first zone, a second zone, a third zone, a fourth zone, a fifth zone, a sixth zone, and a seventh zone connected in sequence;

    Optionally, the working temperature in the first zone is 110-115°C, the working temperature in the second zone is 115-120°C, the working temperature in the third zone is 115-120°C, and the working temperature in the fourth zone is 120°C. -125℃, the working temperature of the fifth zone is 120-125℃, the working temperature of the sixth zone is 120-130℃, and the working temperature of the seventh zone is 125-130℃;

    Optionally, the wire made in step (2) is performed by a wire extruder;

    Optionally, in step (2), the wire extruder includes a zone A, a zone B, a zone C, and a zone D that are sequentially connected;

    Optionally, the working temperature of the A zone is 110-120°C, the working temperature of the B zone is 135-145°C, the working temperature of the C zone is 145-155°C, and the working temperature of the D zone is 150-160°C;

    Optionally, the radiation crosslinking is performed by an electron accelerator, and the radiation dose is 8-12 Mrad.
12. The application of the building wire cable material according to any one of claims 1-9 in the preparation of cables.