Environment-friendly flame-retardant cable material

Abstract

The invention discloses an environment-friendly flame-retardant cable material. The environment-friendly flame-retardant cable material is prepared from the following components in parts by weight: 30 to 40 parts of polyethylene, 5 to 20 parts of ethylene-vinyl acetate copolymer, 5 to 10 parts of POE-g-GMA, 30 to 40 parts of inorganic flame retardant, 1 to 10 parts of synergistic flame retardant, 1 to 2 parts of antioxidant and 5 to 6 parts of auxiliary agent, carrying out vacuum drying on the polyethylene, the ethylene-vinyl acetate copolymer and the POE-g-GMA at 60 DEG C for 12 hours to remove moisture; fully mixing the dried polyethylene, ethylene-vinyl acetate copolymer and POE-g-GMA with an inorganic flame retardant, a synergistic flame retardant, an antioxidant and an auxiliary agent to form a mixture, placing the mixture on an open mill, and mixing at 100 DEG C; after mixing is completed, the mixture is placed in a vacuum press vulcanizer to be subjected to mold pressing for 10 min at the temperature of 150 DEG C and the pressure of 8 MPa, and the environment-friendly flame-retardant cable material is prepared. According to the environment-friendly flame-retardant cable material, the ethylene-vinyl acetate copolymer is introduced into the polyethylene base material, so that the thermal stability of the cable material can be obviously improved.

Description

Technical Field

[0001] The invention relates to the technical field of cable materials, and in particular to an environmentally friendly flame-retardant cable material. Background Art

[0002] The commonly used polymer matrices for low-smoke halogen-free flame-retardant cable materials are mainly polyethylene (PE), polypropylene (PP), polyolefin elastomer (POE), ethylene propylene diene monomer (EPDM), ethylene-vinyl acetate copolymer (EVA) and polyurethane elastomer (TPU). Among them, PE has excellent mechanical and electrical insulation, processing performance, the ability to induce cross-linking at higher temperatures, and excellent dielectric properties in a wide frequency range, making PE one of the most common materials for the insulation layer and sheath layer of low-smoke halogen-free flame-retardant cables. Due to the differences in molecular weight and molecular branching, PE can be divided into low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE) and high-density polyethylene (HDPE). Among them, due to the high flexibility and mechanical strength of LDPE and LLDPE, their use in the field of wire and cable manufacturing is significantly higher than that of HDPE.

[0003] Although PE material has good processing performance and mechanical properties, its high crystallinity leads to its high hardness and poor bending resistance. In addition, PE has poor flame retardant properties and cannot meet the requirements for direct use of low-smoke halogen-free flame retardant cables. Therefore, PE material needs to be modified to improve its actual use value. Summary of the invention

[0004] Based on this, it is necessary to provide an environmentally friendly flame-retardant cable material to address the technical problem that the existing PE material has insufficient flame-retardant properties.

[0005] An environmentally friendly flame-retardant cable material comprises the following components by weight: 30-40 parts of polyethylene, 5-20 parts of ethylene-vinyl acetate copolymer, 5-10 parts of POE-g-GMA, 30-40 parts of inorganic flame retardant, 1-10 parts of synergistic flame retardant, 1-2 parts of antioxidant and 5-6 parts of auxiliary agent.

[0006] Polyethylene, ethylene-vinyl acetate copolymer and POE-g-GMA are vacuum dried at 60°C for 12 hours to remove moisture; the dried polyethylene, ethylene-vinyl acetate copolymer, POE-g-GMA are fully mixed with inorganic flame retardants, synergistic flame retardants, antioxidants and additives to form a mixture, which is placed on an open mill and kneaded at 100°C; after kneading, it is placed on a vacuum flat vulcanizer and molded at 150°C and 8MPa pressure for 10 minutes to obtain an environmentally friendly flame retardant cable material.

[0007] In one embodiment, the above-mentioned environmentally friendly flame-retardant cable material further includes 1-3 parts of hydroxy silicone oil, which is added to the above-mentioned mixture, kneaded together and molded to obtain the environmentally friendly flame-retardant cable material.

[0008] In one embodiment, the inorganic flame retardant is a mixture of magnesium hydroxide and aluminum hydroxide.

[0009] In one embodiment, the synergistic flame retardant is a mixture of one or more of magnesium-rich silicate, nitrogen-based flame retardant and phosphorus-based flame retardant.

[0010] In one embodiment, the environmentally friendly flame-retardant cable material further includes 2.8wt% of trimethylolpropane trimethacrylate. After the above-mentioned mixture is melted for 15 minutes, a preset amount of trimethylolpropane trimethacrylate is added and the mixture is mixed for 5 minutes, followed by molding to obtain the cable material; the cable material is irradiated under cobalt-60 conditions, and the irradiation dose is 15-16kGy.

[0011] In one embodiment, the above-mentioned environmentally friendly flame-retardant cable material includes the following components by weight: 30 parts of polyethylene, 5 parts of ethylene-vinyl acetate copolymer, 5 parts of POE-g-GMA, 30 parts of a mixture of magnesium hydroxide and aluminum hydroxide, 1 part of magnesium-rich silicate, 1 part of antioxidant and 5 parts of additives; the environmentally friendly flame-retardant cable material also includes 1 part of hydroxyl silicone oil; the environmentally friendly flame-retardant cable material also includes 2.8wt% of trimethylolpropane trimethacrylate.

[0012] In one embodiment, the above-mentioned polyethylene, ethylene-vinyl acetate copolymer and POE-g-GMA are vacuum dried at 60°C for 12 hours to remove moisture; the dried polyethylene, ethylene-vinyl acetate copolymer, POE-g-GMA are fully mixed with a mixture of magnesium hydroxide and aluminum hydroxide, magnesium-rich silicate, antioxidant and additives to form a mixture and placed on an open mill, mixed at 100°C for 15 minutes, and then a preset amount of trimethylolpropane trimethacrylate is added and mixed for 5 minutes; after mixing, it is placed in a vacuum flat vulcanizer and molded at 150°C and 8MPa pressure for 10 minutes to obtain an environmentally friendly flame-retardant cable material; the cable material is irradiated under cobalt-60 conditions, and the irradiation dose is 15kGy.

[0013] In one embodiment, the above-mentioned environmentally friendly flame-retardant cable material includes the following components by weight: 40 parts of polyethylene, 20 parts of ethylene-vinyl acetate copolymer, 10 parts of POE-g-GMA, 40 parts of a mixture of magnesium hydroxide and aluminum hydroxide, 10 parts of magnesium-rich silicate, 2 parts of antioxidant and 6 parts of additives; the environmentally friendly flame-retardant cable material also includes 3 parts of hydroxy silicone oil; the environmentally friendly flame-retardant cable material also includes 2.8wt% of trimethylolpropane trimethacrylate.

[0014] In one embodiment, the above-mentioned polyethylene, ethylene-vinyl acetate copolymer and POE-g-GMA are vacuum dried at 60°C for 12 hours to remove moisture; the dried polyethylene, ethylene-vinyl acetate copolymer, POE-g-GMA are fully mixed with a mixture of magnesium hydroxide and aluminum hydroxide, magnesium-rich silicate, antioxidant and additives to form a mixture and placed on an open mill, mixed at 100°C for 15 minutes, and then a preset amount of trimethylolpropane trimethacrylate is added and mixed for 5 minutes; after mixing, it is placed in a vacuum flat vulcanizer and molded at 150°C and 8MPa pressure for 10 minutes to obtain an environmentally friendly flame-retardant cable material; the cable material is irradiated under cobalt-60 conditions, and the irradiation dose is 16kGy.

[0015] In one embodiment, the above-mentioned environmentally friendly flame-retardant cable material includes the following components by weight: 30 parts of polyethylene, 10 parts of ethylene-vinyl acetate copolymer, 5 parts of POE-g-GMA, 40 parts of a mixture of magnesium hydroxide and aluminum hydroxide, 5 parts of magnesium-rich silicate, 1 part of an antioxidant and 6 parts of an additive; the environmentally friendly flame-retardant cable material also includes 3 parts of hydroxy silicone oil; the environmentally friendly flame-retardant cable material also includes 2.8wt% of trimethylolpropane trimethacrylate.

[0016] In one embodiment, the above-mentioned polyethylene, ethylene-vinyl acetate copolymer and POE-g-GMA are vacuum dried at 60°C for 12 hours to remove moisture; the dried polyethylene, ethylene-vinyl acetate copolymer, POE-g-GMA are fully mixed with a mixture of magnesium hydroxide and aluminum hydroxide, magnesium-rich silicate, antioxidant and additives to form a mixture and placed on an open mill, mixed at 100°C for 15 minutes, and then a preset amount of trimethylolpropane trimethacrylate is added and mixed for 5 minutes; after mixing, it is placed in a vacuum flat vulcanizer and molded at 150°C and 8MPa pressure for 10 minutes to obtain an environmentally friendly flame-retardant cable material; the cable material is irradiated under cobalt-60 conditions, and the irradiation dose is 15.8kGy.

[0017] The above-mentioned environmentally friendly flame-retardant cable material can significantly improve the thermal stability of the cable material by introducing ethylene-vinyl acetate copolymer into the polyethylene substrate. The ethylene-vinyl acetate copolymer can improve the limiting oxygen index of the cable material, increase the continuity and density of the carbon layer, and reduce the number of drops of the cable material during combustion, thereby improving the graphitization degree of the carbon slag after combustion of the cable material, and the carbon layer structure after graphitization is more stable and dense; ethylene-vinyl acetate copolymer can improve the interaction between the inorganic particles inside the cable material and the polyethylene matrix, resulting in an increase in the storage modulus of the product in the low-frequency region; based on this, the introduction of ethylene-vinyl acetate copolymer can effectively improve the flame retardant properties of the cable material while ensuring environmental friendliness. DETAILED DESCRIPTION

[0018] In order to make the above-mentioned purpose, features and advantages of the present invention more obvious and easy to understand, the specific embodiments of the present invention are described in detail below. In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present invention, so the present invention is not limited by the specific embodiments disclosed below.

[0019] The invention discloses an environment-friendly flame-retardant cable material, which comprises the following components by weight: 30-40 parts of polyethylene, 5-20 parts of ethylene-vinyl acetate copolymer, 5-10 parts of POE-g-GMA, 30-40 parts of inorganic flame retardant, 1-10 parts of synergistic flame retardant, 1-2 parts of antioxidant and 5-6 parts of auxiliary agent. Specifically, polyethylene, ethylene-vinyl acetate copolymer and POE-g-GMA are vacuum dried at 60°C for 12 hours to remove moisture, so as to avoid volatilization of moisture during the molding process to generate bubbles and cause defects in the cable material; the dried polyethylene, ethylene-vinyl acetate copolymer, POE-g-GMA are fully mixed with inorganic flame retardants, synergistic flame retardants, antioxidants and additives to form a mixture, which is placed on an open mill and kneaded at 100°C; after kneading, it is placed on a vacuum flat vulcanizer and molded at 150°C and 8MPa pressure for 10 minutes to obtain an environmentally friendly flame retardant cable material. The environmentally friendly flame-retardant cable material of the present invention can significantly improve the thermal stability of the cable material by introducing ethylene-vinyl acetate copolymer into a polyethylene substrate. The ethylene-vinyl acetate copolymer can improve the limiting oxygen index of the cable material, increase the continuity and density of the carbon layer, and reduce the number of drops of the cable material during combustion, thereby improving the graphitization degree of the carbon slag after the cable material is burned, and the carbon layer structure after graphitization is more stable and dense; the ethylene-vinyl acetate copolymer can improve the interaction between the inorganic particles inside the cable material and the polyethylene matrix, resulting in an increase in the storage modulus of the product in the low-frequency region; based on this, the introduction of the ethylene-vinyl acetate copolymer can effectively improve the flame retardant performance of the cable material while ensuring environmental friendliness.

[0020] Furthermore, the environmentally friendly flame retardant cable material further comprises 1-3 parts of hydroxy silicone oil, which is added to the above-mentioned mixture, kneaded together and molded to obtain the environmentally friendly flame retardant cable material. The environmentally friendly flame retardant cable material of the present invention can improve the wear resistance of the cable material by adding hydroxy silicone oil.

[0021] Specifically, the above-mentioned inorganic flame retardant adopts a mixture of magnesium hydroxide and aluminum hydroxide. The introduction of ethylene-vinyl acetate copolymer can enhance the interaction between magnesium hydroxide and aluminum hydroxide and the polyethylene matrix, partially forming a binding glue to prevent the inorganic flame retardant from decomposing at low temperatures, thereby improving the heat resistance of the cable material.

[0022] Specifically, the above-mentioned synergistic flame retardant adopts a mixture of one or more of magnesium-rich silicate, nitrogen-based flame retardant and phosphorus-based flame retardant. In this embodiment, the above-mentioned synergistic flame retardant adopts magnesium-rich silicate, which can increase the initial decomposition temperature of the cable material, increase the carbonization rate and residual carbon content of the cable material, and at the same time reduce the cleanliness ability of the cable material; and the addition of magnesium-rich silicate can play a synergistic flame retardant role with the metal hydroxide flame retardant, forming an oxide barrier layer that can promote the carbonization of the cable material matrix, thereby improving the graphitization degree of the cable material, and the structural strength of the residual carbon of the cable material after combustion is relatively high, which solves the problem of dripping of the cable material during the combustion process.

[0023] Furthermore, the environmentally friendly flame-retardant cable material further includes 2.8wt% of trimethylolpropane trimethacrylate, and the above-mentioned mixed material is melted for 15 minutes, and a preset amount of trimethylolpropane trimethacrylate is added to continue mixing for 5 minutes, and then molded to obtain the cable material; the cable material is irradiated under cobalt-60 conditions, and the irradiation dose is 15-16kGy. The environmentally friendly flame-retardant cable material of the present invention can effectively improve the thermal stability of the cable material by adding an irradiation sensitizer and performing irradiation crosslinking, and the tensile strength of the cable material after crosslinking at a low irradiation dose is improved. Example

[0024] In this embodiment, the environmentally friendly flame-retardant cable material includes the following components by weight: 30 parts of polyethylene, 5 parts of ethylene-vinyl acetate copolymer, 5 parts of POE-g-GMA, 30 parts of a mixture of magnesium hydroxide and aluminum hydroxide, 1 part of magnesium-rich silicate, 1 part of antioxidant and 5 parts of additives; the environmentally friendly flame-retardant cable material also includes 1 part of hydroxy silicone oil; the environmentally friendly flame-retardant cable material also includes 2.8wt% of trimethylolpropane trimethacrylate.

[0025] Polyethylene, ethylene-vinyl acetate copolymer and POE-g-GMA were vacuum dried at 60°C for 12 hours to remove moisture; the dried polyethylene, ethylene-vinyl acetate copolymer, POE-g-GMA were fully mixed with a mixture of magnesium hydroxide and aluminum hydroxide, magnesium-rich silicate, antioxidant and additives to form a mixture, which was placed on an open mill, mixed at 100°C for 15 minutes, and then a preset amount of trimethylolpropane trimethacrylate was added and mixed for 5 minutes; after mixing, it was placed in a vacuum flat vulcanizer and molded at 150°C and 8MPa pressure for 10 minutes to obtain an environmentally friendly flame-retardant cable material; the cable material was irradiated under cobalt-60 conditions with an irradiation dose of 15kGy. Example

[0026] In this embodiment, the environmentally friendly flame-retardant cable material includes the following components by weight: 40 parts of polyethylene, 20 parts of ethylene-vinyl acetate copolymer, 10 parts of POE-g-GMA, 40 parts of a mixture of magnesium hydroxide and aluminum hydroxide, 10 parts of magnesium-rich silicate, 2 parts of antioxidant and 6 parts of additives; the environmentally friendly flame-retardant cable material also includes 3 parts of hydroxy silicone oil; the environmentally friendly flame-retardant cable material also includes 2.8wt% of trimethylolpropane trimethacrylate.

[0027] Polyethylene, ethylene-vinyl acetate copolymer and POE-g-GMA were vacuum dried at 60°C for 12 hours to remove moisture; the dried polyethylene, ethylene-vinyl acetate copolymer, POE-g-GMA were fully mixed with a mixture of magnesium hydroxide and aluminum hydroxide, magnesium-rich silicate, antioxidant and additives to form a mixture, which was placed on an open mill, mixed at 100°C for 15 minutes, and then a preset amount of trimethylolpropane trimethacrylate was added and mixed for 5 minutes; after mixing, it was placed in a vacuum flat vulcanizer and molded at 150°C and 8MPa pressure for 10 minutes to obtain an environmentally friendly flame-retardant cable material; the cable material was irradiated under cobalt-60 conditions with an irradiation dose of 16kGy. Example

[0028] In this embodiment, the environmentally friendly flame-retardant cable material includes the following components by weight: 30 parts of polyethylene, 10 parts of ethylene-vinyl acetate copolymer, 5 parts of POE-g-GMA, 40 parts of a mixture of magnesium hydroxide and aluminum hydroxide, 5 parts of magnesium-rich silicate, 1 part of an antioxidant and 6 parts of an auxiliary agent; the environmentally friendly flame-retardant cable material also includes 3 parts of hydroxy silicone oil; the environmentally friendly flame-retardant cable material also includes 2.8wt% of trimethylolpropane trimethacrylate.

[0029] Polyethylene, ethylene-vinyl acetate copolymer and POE-g-GMA were vacuum dried at 60°C for 12 hours to remove moisture; the dried polyethylene, ethylene-vinyl acetate copolymer, POE-g-GMA were fully mixed with a mixture of magnesium hydroxide and aluminum hydroxide, magnesium-rich silicate, antioxidant and additives to form a mixture, which was placed on an open mill, mixed at 100°C for 15 minutes, and then a preset amount of trimethylolpropane trimethacrylate was added and mixed for 5 minutes; after mixing, it was placed in a vacuum flat vulcanizer and molded at 150°C and 8MPa pressure for 10 minutes to obtain an environmentally friendly flame-retardant cable material; the cable material was irradiated under cobalt-60 conditions with an irradiation dose of 15.8kGy.

[0030] In summary, the environmentally friendly flame-retardant cable material disclosed in the present invention can significantly improve the thermal stability of the cable material by introducing ethylene-vinyl acetate copolymer into the polyethylene substrate. The ethylene-vinyl acetate copolymer can improve the limiting oxygen index of the cable material, increase the continuity and density of the carbon layer, and reduce the number of drops of the cable material during combustion, thereby improving the graphitization degree of the carbon slag after combustion of the cable material, and the carbon layer structure after graphitization is more stable and dense; the ethylene-vinyl acetate copolymer can improve the interaction between the inorganic particles inside the cable material and the polyethylene matrix, resulting in an increase in the storage modulus of the product in the low-frequency region; based on this, the introduction of the ethylene-vinyl acetate copolymer can effectively improve the flame retardant properties of the cable material while ensuring environmental friendliness.

[0031] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0032] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. An environmentally friendly flame-retardant cable material, characterized in that: The composition comprises the following components by weight: 30-40 parts of polyethylene, 5-20 parts of ethylene-vinyl acetate copolymer, 5-10 parts of POE-g-GMA, 30-40 parts of inorganic flame retardant, 1-10 parts of synergistic flame retardant, 1-2 parts of antioxidant and 5-6 parts of auxiliary agent; Polyethylene, ethylene-vinyl acetate copolymer and POE-g-GMA are vacuum dried at 60°C for 12 hours to remove moisture; the dried polyethylene, ethylene-vinyl acetate copolymer, POE-g-GMA are fully mixed with inorganic flame retardants, synergistic flame retardants, antioxidants and additives to form a mixture, which is placed on an open mill and kneaded at 100°C; after kneading, it is placed on a vacuum flat vulcanizer and molded at 150°C and 8MPa pressure for 10 minutes to obtain an environmentally friendly flame retardant cable material.

2. The environmentally friendly flame-retardant cable material according to claim 1, characterized in that: The environmentally friendly flame-retardant cable material also includes 1-3 parts of hydroxy silicone oil, which is added to the above-mentioned mixed material, kneaded together and molded to obtain the environmentally friendly flame-retardant cable material.

3. The environmentally friendly flame-retardant cable material according to claim 2, characterized in that: The inorganic flame retardant is a mixture of magnesium hydroxide and aluminum hydroxide.

4. The environmentally friendly flame-retardant cable material according to claim 3, characterized in that: The synergistic flame retardant is a mixture of one or more of magnesium-rich silicate, nitrogen-based flame retardant and phosphorus-based flame retardant.

5. The environmentally friendly flame-retardant cable material according to claim 4, characterized in that: The environmentally friendly flame-retardant cable material also includes 2.8wt% of trimethylolpropane trimethacrylate. After the mixed material is melted for 15 minutes, a preset amount of trimethylolpropane trimethacrylate is added and the mixing is continued for 5 minutes, and then the cable material is obtained by molding; the cable material is irradiated under cobalt-60 conditions, and the irradiation dose is 15-16kGy.

6. The environmentally friendly flame-retardant cable material according to claim 5, characterized in that: The environmentally friendly flame-retardant cable material includes the following components by weight: 30 parts of polyethylene, 5 parts of ethylene-vinyl acetate copolymer, 5 parts of POE-g-GMA, 30 parts of a mixture of magnesium hydroxide and aluminum hydroxide, 1 part of magnesium-rich silicate, 1 part of antioxidant and 5 parts of additives; the environmentally friendly flame-retardant cable material also includes 1 part of hydroxy silicone oil; The environmentally friendly flame retardant cable material also includes 2.8 wt % of trimethylolpropane trimethacrylate.

7. The environmentally friendly flame-retardant cable material according to claim 6, characterized in that: Polyethylene, ethylene-vinyl acetate copolymer and POE-g-GMA were vacuum dried at 60°C for 12 hours to remove moisture; the dried polyethylene, ethylene-vinyl acetate copolymer, POE-g-GMA were fully mixed with a mixture of magnesium hydroxide and aluminum hydroxide, magnesium-rich silicate, antioxidant and additives to form a mixture, which was placed on an open mill, mixed at 100°C for 15 minutes, and then a preset amount of trimethylolpropane trimethacrylate was added and mixed for 5 minutes; after mixing, it was placed in a vacuum flat vulcanizer and molded at 150°C and 8MPa pressure for 10 minutes to obtain an environmentally friendly flame-retardant cable material; the cable material was irradiated under cobalt-60 conditions with an irradiation dose of 15kGy.

8. The environmentally friendly flame-retardant cable material according to claim 5, characterized in that: The environmentally friendly flame-retardant cable material includes the following components by weight: 40 parts of polyethylene, 20 parts of ethylene-vinyl acetate copolymer, 10 parts of POE-g-GMA, 40 parts of a mixture of magnesium hydroxide and aluminum hydroxide, 10 parts of magnesium-rich silicate, 2 parts of antioxidant and 6 parts of additives; the environmentally friendly flame-retardant cable material also includes 3 parts of hydroxy silicone oil; the environmentally friendly flame-retardant cable material also includes 2.8wt% of trimethylolpropane trimethacrylate.

9. The environmentally friendly flame-retardant cable material according to claim 8, characterized in that: Polyethylene, ethylene-vinyl acetate copolymer and POE-g-GMA were vacuum dried at 60°C for 12 hours to remove moisture; the dried polyethylene, ethylene-vinyl acetate copolymer, POE-g-GMA were fully mixed with a mixture of magnesium hydroxide and aluminum hydroxide, magnesium-rich silicate, antioxidant and additives to form a mixture, which was placed on an open mill, mixed at 100°C for 15 minutes, and then a preset amount of trimethylolpropane trimethacrylate was added and mixed for 5 minutes; after mixing, it was placed in a vacuum flat vulcanizer and molded at 150°C and 8MPa pressure for 10 minutes to obtain an environmentally friendly flame-retardant cable material; the cable material was irradiated under cobalt-60 conditions with an irradiation dose of 16kGy.