Low-smoke flame-retardant cold-resistant wear-resistant TPE (thermoplastic elastomer) cable composite material as well as preparation method and application thereof

Abstract

The invention discloses a low-smoke flame-retardant cold-resistant wear-resistant TPE (thermoplastic elastomer) cable composite material as well as a preparation method and application thereof, and relates to the technical field of cable materials. The TPE cable composite material comprises the following components: SEBS, polypropylene, an ethylene-vinyl acetate copolymer, a compatilizer, a composite flame retardant, an inorganic filler and an irradiation crosslinking auxiliary agent, and the composite flame retardant comprises a hydroxide flame retardant and a carbon-forming flame retardant; the inorganic filler comprises silane modified glass flakes and borate whiskers. The TPE cable composite material disclosed by the invention has high dielectric strength, high tear resistance and high flexibility, and the specific inorganic filler and the composite halogen-free flame retardant are added, so that the material can balance the cold resistance, wear resistance and low smoke density.

Description

Technical Field

[0001] The present invention belongs to the technical field of cable materials, and in particular relates to a low-smoke flame-retardant, cold-resistant, and wear-resistant TPE cable composite material, a manufacturing method thereof, and applications thereof. Background Art

[0002] Traditional bromine-containing flame-retardant wires and cables produce large amounts of toxic smoke and corrosive gases during combustion, which will accelerate the asphyxiation of people at the fire scene and increase the difficulty of rescue workers; and the released corrosive gases will corrode and destroy electrical appliances at and near the fire scene; the market demand for low-smoke halogen-free flame-retardant cable materials is gradually increasing.

[0003] TPE (thermoplastic elastomer) materials, with their high elasticity, strength, and resilience, are ideal for wire and cable applications. TPE wire and cable materials are typically formulated with a thermoplastic elastomer (HSEBS) triblock copolymer and polypropylene (PP), offering a good balance between toughness and mechanical strength. While radiation crosslinking can significantly improve wear resistance and mechanical strength, the PP molecular chain structure is susceptible to degradation at high radiation doses, leading to structural changes in the material, reduced flame retardancy, and compromised dielectric strength. Low-smoke flame-retardant TPE materials typically require a large amount (over 40%) of halogen-free flame retardants to meet flame retardancy and low smoke density requirements. However, high levels of halogen-free flame retardants can lead to a decrease in wear resistance and mechanical properties, particularly at low temperatures, making them brittle, limiting their application in cold or high-altitude environments. Therefore, there is a need to develop a halogen-free flame-retardant TPE material that balances cold resistance, wear resistance, and low smoke density while ensuring the performance characteristics of cable materials. Summary of the Invention

[0004] The purpose of the present invention is to provide a TPE cable composite material which is halogen-free and heat-resistant and has the characteristics of high cold resistance, high wear resistance and low smoke density.

[0005] Another object of the present invention is to provide a method for manufacturing a TPE cable composite material.

[0006] Another object of the present invention is to provide an application of a TPE cable composite material in the preparation of a cable.

[0007] Another object of the present invention is to provide a cable product.

[0008] The above-mentioned purpose of the present invention is achieved through the following technical solutions:

[0009] The present invention protects a TPE cable composite material, comprising the following components in parts by weight:

[0010]

[0011] The composite flame retardant comprises a hydroxide flame retardant and a carbon-forming flame retardant in a mass ratio of (2-6):1;

[0012] The inorganic filler comprises silane-modified glass flakes and borate whiskers in a mass ratio of (1-4):1.

[0013] The TPE cable composite material of the present invention uses SEBS as a matrix and is compounded with specific contents of PP and EVA. It has high dielectric strength, high tear resistance and high flexibility. At the same time, specific inorganic fillers and composite halogen-free flame retardants are added to enable the material to balance its cold resistance, wear resistance and low smoke density.

[0014] The composite flame retardant is primarily a low-smoke-density hydroxide flame retardant, and the compounded carbon-forming flame retardant can synergize with glass flakes and borate whiskers to form a strong barrier layer in the carbonized structure after combustion, inhibiting the emission of smoke and reducing smoke density. Furthermore, the specific inorganic filler of the present invention can improve the strength and toughness of the TPE material and improve its wear resistance. At the same time, the specific amount of radiation cross-linking efficiency can improve the radiation cross-linking efficiency and reduce the radiation dose required for radiation cross-linking, thereby enabling the TPE material to meet the mechanical strength, wear resistance, and dielectric strength requirements of cable materials at low radiation doses, while avoiding the problems of decreased tensile strength of the material caused by high radiation doses and brittleness at low temperatures.

[0015] Preferably, the weight percentage of the SEBS is a range value of one or any two of 35 parts, 36 parts, 37 parts, 38 parts, 39 parts, 40 parts, 41 parts, 42 parts, 43 parts, 44 parts, 45 parts, 46 parts, 47 parts, 48 ​​parts, 49 parts and 50 parts.

[0016] Preferably, the styrene content of the SEBS is 25-40 wt %; more preferably 28-35 wt %.

[0017] Preferably, the SEBS has a melt flow rate at 230° C. and 5 kg of 1-30 g / 10 min, more preferably 5-25 g / 10 min.

[0018] Preferably, the weight percentage of the polypropylene is in the range of one or any two of 15 parts, 16 parts, 17 parts, 18 parts, 19 parts, 20 parts, 21 parts, 22 parts, 23 parts, 24 parts and 25 parts.

[0019] Furthermore, the polypropylene is at least one of random copolymer polypropylene (PP-R), homopolymer polypropylene (PP-H) and block copolymer polypropylene (PP-B), preferably random copolymer polypropylene.

[0020] Preferably, the polypropylene has a melt flow rate at 230° C. and 2.16 kg of 5-20 g / 10 min, more preferably 8-11 g / 10 min.

[0021] Preferably, the weight percentage of the ethylene-vinyl acetate copolymer (EVA) is in the range of one or any two of 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts and 15 parts.

[0022] Furthermore, the VA content in the ethylene-vinyl acetate copolymer is 28-42 wt%.

[0023] Furthermore, the compatibilizer is a SEBS grafted maleic anhydride copolymer, and the maleic anhydride grafting rate is 1-2.5%, preferably 1.4-2.0%.

[0024] Furthermore, the carbon-forming flame retardant is at least one of resorcinol bis(diphenyl phosphate), bisphenol A-bis(diphenyl phosphate) and melamine cyanurate.

[0025] Furthermore, the hydroxide flame retardant is magnesium hydroxide and / or aluminum hydroxide; preferably, the content of magnesium hydroxide in the hydroxide flame retardant is not less than 60 wt %.

[0026] Furthermore, the silane-modified glass flakes are formed by modifying the surface of the glass flakes with a silane coupling agent containing unsaturated bonds.

[0027] Preferably, the silane coupling agent containing an unsaturated bond is any one of γ-methacryloxypropyltrimethoxysilane, vinyltrimethoxysilane and vinyltriethoxysilane.

[0028] Furthermore, the average thickness of the glass flakes is 0.5 to 6 μm.

[0029] Furthermore, the average particle size of the glass flakes is 100 to 600 μm.

[0030] Furthermore, the borate whiskers are magnesium borate whiskers with an average length of 10-40 μm.

[0031] Furthermore, the aspect ratio of the borate whiskers is ≥10, preferably 10-30.

[0032] Furthermore, the radiation cross-linking auxiliary agent is at least one of triallyl isocyanurate (TAIC), trimethylolpropane trimethacrylate (TMPTMA) and triallyl cyanurate (TAC).

[0033] Furthermore, the initiator is dicumyl peroxide.

[0034] Conventional additives in the art may also be added to the TPE cable composite material of the present invention, including but not limited to at least one of an antioxidant, a lubricant, a plasticizer, and a processing aid. The content of the additive may be 1-15 wt%.

[0035] Preferably, the TPE cable composite material of the present invention further comprises 8-15 parts of a plasticizer, 1-5 parts of an antioxidant, and 1-5 parts of a lubricant.

[0036] Optionally, the plasticizer is white oil.

[0037] Optionally, the antioxidant is antioxidant 1010 and / or antioxidant 168.

[0038] Optionally, the lubricant is PE wax.

[0039] The present invention protects a method for manufacturing a TPE cable composite material, comprising the following steps: uniformly mixing raw material components in a prescribed amount, melt-extruding and granulating to obtain the TPE cable composite material.

[0040] The present invention protects the use of a TPE cable composite material in preparing a cable.

[0041] The present invention protects a cable product, which is obtained by extruding the TPE cable composite material into a wire and then irradiating and cross-linking it, with an irradiation dose of 3-6 Mrad.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] The present invention discloses a TPE cable composite material, based on SEBS and compounded with specific amounts of PP and EVA. The composite material exhibits high dielectric strength, high tear resistance, and high flexibility. The addition of a specific inorganic filler and a composite halogen-free flame retardant ensures a balanced performance among cold resistance, wear resistance, and low smoke density. These inorganic fillers and composite halogen-free flame retardants increase the reaction point of the radiation cross-linking reaction, reduce the radiation dose required for cross-linking, and enhance mechanical strength and low-temperature toughness. Furthermore, the composite material forms a barrier layer during combustion, controlling smoke density and achieving a balanced performance among cold resistance, wear resistance, and low smoke density. DETAILED DESCRIPTION

[0044] The present invention will be further described below with reference to specific embodiments, but the examples do not limit the present invention in any form.

[0045] The following examples and comparative examples use the following raw materials:

[0046] SEBS-1: hydrogenated styrene-butadiene block copolymer, styrene content 30 wt%; G1650, Kraton Corporation, USA.

[0047] SEBS-2: hydrogenated styrene-butadiene block copolymer, styrene content 33 wt%; G1651, Kraton Corporation, USA.

[0048] PP-1: Polypropylene random copolymer (PP-R), K8003, Sinopec.

[0049] PP-2: Homopolymer polypropylene (PP-H), 1105K, ExxonMobil, USA.

[0050] EVA-1: ethylene-vinyl acetate copolymer, VA content is 40wt%; 40L-03, DuPont Company, USA.

[0051] EVA-2: ethylene-vinyl acetate copolymer, VA content of 33 wt%; EVA150, Mitsui Chemicals, Japan.

[0052] SEBS-g-MAH: SEBS grafted maleic anhydride copolymer; FG1901GT, Kraton, USA.

[0053] Flame retardant A1: magnesium hydroxide, Mitsui Chemicals, Japan.

[0054] Flame retardant A2: aluminum hydroxide, Huber Company, USA.

[0055] Flame retardant B1: resorcinol bis(diphenyl phosphate) (RDP), Daihachi Chemical Co., Ltd., Japan.

[0056] Flame retardant B2: bisphenol A-bis(diphenyl phosphate) (BDP), Albemarle, USA.

[0057] Flame retardant B3: melamine cyanurate (MCA), BASF, Germany.

[0058] Magnesium borate whiskers: Shanghai Kaishefeng Industrial Co., Ltd.

[0059] Basic magnesium sulfate whiskers: Qinghai Western Magnesium Industry Co., Ltd.

[0060] Radiation cross-linking aid: triacrylic isocyanurate (TAIC), Wuhan Lanabai Pharmaceutical Chemical Company.

[0061] White oil: PW-90, Idemitsu Kosan Co., Ltd., Japan.

[0062] Initiator: dicumyl peroxide, Shandong Ruihuang Chemical Company.

[0063] Antioxidant: Antioxidant 1010 and Antioxidant 168 in a mass ratio of 2:1.

[0064] Lubricant: PE wax, CS-12N, Korean COSCHEM.

[0065] Glass flake A1: Nippon Glass Co., Ltd., FLWKAREFG-600.

[0066] Modified glass flake B1: Nippon Sheet Glass Co., Ltd., FLWKAREFG-600, modified with silane coupling agent.

[0067] Modified glass flake B2: Nippon Sheet Glass Co., Ltd., FINEFLAKE MEG160FY, modified with silane coupling agent.

[0068] The preparation method of the above modified glass flakes (B1, B2) is as follows: dilute γ-methacryloxypropyltrimethoxysilane (KH-570 silane coupling agent) in anhydrous ethanol to a volume concentration of 2%; then add 1 mol / L oxalic acid solution to adjust the pH to 3, add glass flakes at 50°C and stir for 4 hours. The amount of glass flakes added is 2 g / mL. After drying at 60°C for 24 hours, modified glass flakes are obtained.

[0069] Examples 1-18 and Comparative Examples 1-8

[0070] This embodiment provides a series of TPE cable composite materials, the difference between which is only the type and amount of each component. In parts by weight, Examples 1-18 and Comparative Examples 1-8 include the components shown in Table 1-3.

[0071] The preparation method of the TPE cable composite material of each embodiment and comparative example comprises the following steps:

[0072] SEBS, PP and EVA were put into a high-speed mixer and mixed uniformly at a speed of 1000 rpm, and then the remaining raw material components were added and mixed uniformly; the mixture was put into an internal mixer, and after internal mixing in the internal mixer, it was extruded into granules through a twin-screw extruder. The temperature of the internal mixer was controlled at 150±5°C, and the temperatures of each section of the twin-screw extruder were 155°C-160°C, 160°C-170°C, 170°C-180°C, 180°C-185°C, 185°C-190°C, and 190°C-195°C.

[0073] Table 1 Components of TPE cable composite materials of Examples 1-10 (parts by mass)

[0074]

[0075]

[0076] Table 2 Components of TPE cable composite materials of Examples 11-18 (parts by mass)

[0077]

[0078]

[0079] Table 3 TPE cable composite material components of comparative examples 1-8 (parts by mass)

[0080]

[0081]

[0082] Performance Testing

[0083] The materials of each embodiment and comparative example were injection molded into experimental samples and extruded into wire samples, and then irradiated with a high-energy electron beam (EB) at a dose of 7 Mrad. The following tests were then performed, and the structures are shown in Table 4.

[0084] Tensile strength: Refer to the test method of standard GB / T1040.1-2018.

[0085] Elongation at break: Refer to the test method of standard GB / T1040.1-2018.

[0086] Dielectric strength: Refer to the test method of standard GB / T 1408.1-2006, test temperature 20℃.

[0087] Gel content after irradiation: The test method is to weigh the irradiated sample as W1, soak the sample in a Soxhlet extractor, and extract it with boiling xylene under reflux for 48 hours. The insoluble matter after soaking is removed and the weight of the insoluble matter is weighed after drying. Gel content = W2 / W1*100%.

[0088] Smoke density: Refer to the method of IEC 61034-2 (2013) with the minimum transmittance T min express.

[0089] Low temperature winding test: refer to the method of standard GB / T 2951.14-2008, the test temperature is -40℃.

[0090] Flame retardancy: Tested according to ASTM D3801 to UL 94 vertical burning rating with a thickness of 1.6 mm.

[0091] Abrasion resistance: Refer to the method of IEC 60811-501-2018. If the material is not damaged after 700 frictions, it passes; otherwise, it fails.

[0092] Table 4

[0093]

[0094]

[0095] As can be seen from Table 3, the present invention has high dielectric strength, high tear resistance and high flexibility by adding specific amounts of PP and EVA to SEBS as a matrix, and adding specific inorganic fillers and composite halogen-free flame retardants to enable the material to balance its cold resistance, wear resistance and low smoke density. On the other hand, it can also reduce the irradiation dose required for irradiation cross-linking, improve mechanical strength and low-temperature toughness; at the same time, it can form a barrier layer during combustion to control the smoke density, so that the material can balance its cold resistance, wear resistance and low smoke density. The TPE cable composite material of the present invention has a tensile strength of more than 13.8MPa, an elongation at break of more than 376%, a dielectric strength of more than 31MV / m, a gel content of more than 81% at an irradiation dose of 7Mrad, and a minimum transmittance T min The flame retardant grade reaches V-0, and the material is not damaged after 700 times of friction.

[0096] The above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the embodiments of the present invention. Those skilled in the art will appreciate that other variations or modifications may be made based on the above description. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention are intended to be included within the scope of protection of the claims of the present invention.

Claims

1. A TPE cable composite material, characterized in that: The composition includes the following components in parts by mass: The composite flame retardant comprises a hydroxide flame retardant and a carbon-forming flame retardant in a mass ratio of (2-6):1; The inorganic filler includes silane-modified glass flakes and borate whiskers in a mass ratio of (1-4):

1.

2. The TPE cable composite material according to claim 1, characterized in that: The carbon-forming flame retardant is at least one of resorcinol bis(diphenyl phosphate), bisphenol A-bis(diphenyl phosphate) and melamine cyanurate.

3. The TPE cable composite material according to claim 1, characterized in that: The hydroxide flame retardant is magnesium hydroxide and / or aluminum hydroxide.

4. The TPE cable composite material according to claim 1, characterized in that: The compatibilizer is a SEBS grafted maleic anhydride copolymer, and the maleic anhydride grafting rate is 1% to 2.5%.

5. The TPE cable composite material according to claim 1, characterized in that: The VA content in the ethylene-vinyl acetate copolymer is 28-42 wt%.

6. The TPE cable composite material according to claim 1, characterized in that: The silane-modified glass flakes are formed by modifying the surface of the glass flakes with a silane coupling agent containing unsaturated bonds.

7. The TPE cable composite material according to claim 1, characterized in that: Include at least one of the following (1)-(4): (1) The average thickness of the glass flakes is 0.5 to 6 μm, (2) The average particle size of the glass flakes is 100 to 600 μm, (3) The average length of the borate whiskers is 10-50 μm, (4) The aspect ratio of the borate whiskers is ≥10.

8. A method for manufacturing the TPE cable composite material according to any one of claims 1 to 7, characterized in that: The method comprises the following steps: uniformly mixing the raw material components in the formula amount, melting, extruding and granulating to obtain the TPE cable composite material.

9. Use of the TPE cable composite material according to any one of claims 1 to 7 in the preparation of a cable.

10. A cable product, characterized in that: The TPE cable composite material according to any one of claims 1 to 7 is extruded into a wire and then irradiated and cross-linked with an irradiation dose of 4-8 Mrad to obtain the composite material.

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