Halogen-free flame-retardant thermoset polyolefin material, method for its production and use

Abstract

A halogen-free flame-retardant thermosetting polyolefin material, its preparation method, and its application are disclosed, relating to the field of wire and cable materials technology. The halogen-free flame-retardant thermosetting polyolefin material comprises: 5-20 parts of polyphenylene ether resin, 20-40 parts of styrene elastomer, 20-40 parts of polyethylene, 5-16 parts of maleic anhydride compatibilizer, 20-35 parts of halogen-free flame retardant, 5-10 parts of synergistic flame retardant, and 1-3 parts of crosslinking agent; wherein the halogen-free flame retardant is selected from ammonium polyphosphate and / or melamine cyanurate. The halogen-free flame-retardant thermosetting polyolefin material of this invention uses a specific ratio of polyphenylene ether resin / styrene elastomer / polyethylene system, and adds a specific type of halogen-free flame retardant to improve flame retardant performance without significantly damaging mechanical properties; simultaneously, the material is easily crosslinked after irradiation, meeting the 125℃ temperature resistance rating requirements specified in UL1581, and passing the VW-1 flame retardant test.

Description

Technical Field

[0001] This application relates to the field of wire and cable materials technology, and in particular to a halogen-free flame-retardant thermosetting polyolefin material, its preparation method, and its application. Background Technology

[0002] Polyolefin resins are widely used in cable materials due to their high stability, relatively wide processing range, and excellent insulation properties. However, these olefin resins have limitations in achieving the UL1581 125°C temperature resistance rating and VW-1 flame retardancy. Currently, materials on the market that meet the 125°C temperature resistance rating and VW-1 flame retardancy requirements generally use a synergistic flame retardant method of decabromodiphenyl ethane combined with antimony white and hydroxides. However, the EU REACH regulation explicitly includes decabromodiphenyl ethane as a prohibited substance. Therefore, it is necessary to design new resin flame retardant systems that can simultaneously meet the requirements of mechanical properties, UL1581 125°C temperature resistance rating, and VW-1 flame retardancy when used as cable materials. In addition, when preparing olefin resins as halogen-free flame-retardant high-temperature resistant cable materials, it is necessary to consider not only the temperature resistance of the cable material during the crosslinking process, but also the degree of crosslinking after crosslinking and its anti-aging performance under extreme conditions. When used for cables for internal electrical connections, the smoothness and absence of powder particles on the material surface must also be considered.

[0003] Patent CN102030978A describes a halogen-free flame-retardant PPE cable material composition and its preparation method. It uses a compound system of polyphenylene ether resin, elastomer and polyolefin combined with a flame-retardant system of magnesium hydroxide to achieve high flame retardancy and excellent mechanical properties. However, it is a thermoplastic material with poor temperature resistance and cannot meet the 125°C temperature resistance rating performance requirements specified by UL1581. Summary of the Invention

[0004] The purpose of this invention is to overcome the defects and shortcomings of the prior art and provide a halogen-free flame-retardant thermosetting polyolefin material that is easy to crosslink by radiation, has good anti-aging properties, and can meet the requirements of UL1581 for 125°C temperature resistance and VW-1 flame retardancy.

[0005] Another objective of this invention is to provide a method for preparing halogen-free flame-retardant thermosetting polyolefin materials.

[0006] Another objective of this invention is to provide a flame-retardant cable material.

[0007] The above-mentioned objective of this invention is achieved through the following technical solution: This invention protects a halogen-free flame-retardant thermosetting polyolefin material, comprising the following components in parts by weight: 5-20 parts of polyphenylene ether resin, 20-40 parts of styrene elastomer 20-40 parts of polyethylene 5-16 parts of maleic anhydride compatibilizer 20-35 parts of halogen-free flame retardant 5-10 parts of synergistic flame retardant 1-3 parts of crosslinking agent; The halogen-free flame retardant is selected from ammonium polyphosphate and / or melamine cyanurate.

[0008] In some embodiments, the polyethylene has a mass fraction of not less than 15 wt% in the halogen-free flame-retardant thermosetting polyolefin material.

[0009] In some embodiments, the polyphenylene ether resin content that enables the present invention to achieve its purpose can be any range between 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts, 19 parts, 20 parts or more of the component content.

[0010] In some embodiments, the styrene elastomer content that enables the achievement of the present invention can be any range between 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, 25 parts, 26 parts, 27 parts, 28 parts, 29 parts, 30 parts, 31 parts, 32 parts, 33 parts, 34 parts, 35 parts, 36 parts, 37 parts, 38 parts, 39 parts, 40 parts or more of the component content.

[0011] In some embodiments, the polyethylene content that enables the present invention to achieve its purpose can be any range between 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, 25 parts, 26 parts, 27 parts, 28 parts, 29 parts, 30 parts, 31 parts, 32 parts, 33 parts, 34 parts, 35 parts, 36 parts, 37 parts, 38 parts, 39 parts, 40 parts or more of the component content.

[0012] In some embodiments, the halogen-free flame retardant content that can achieve the purpose of the present invention can be any range between 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, 25 parts, 26 parts, 27 parts, 28 parts, 29 parts, 30 parts, 31 parts, 32 parts, 33 parts, 34 parts, 35 parts or more of the component content.

[0013] In some embodiments, the styrene-based elastomer is selected from styrene-ethylene-butene-styrene block copolymers; preferably, the styrene content in the styrene-based elastomer is 18-42 wt%. The styrene content is tested by infrared spectroscopy.

[0014] In some embodiments, the intrinsic viscosity of the polyphenylene ether resin is 32-45 cm⁻¹. 3 / g. The intrinsic viscosity was determined using method a of HG / T 2364-1992, with toluene as the solvent.

[0015] In some embodiments, the polyethylene is selected from LDPE and / or LLDPE; preferably, the polyethylene has a melt flow rate of 0.1-10 g / 10 min at 190°C and a load of 2.16 kg. The melt flow rate is tested according to ISO 1133-1:2011 under the conditions of 230°C / 2.16 kg. In some embodiments, the halogen-free flame retardant is selected from ammonium polyphosphate and melamine cyanurate in a mass ratio of 1:(0.5-4). Preferably, the mass ratio of ammonium polyphosphate to melamine cyanurate is 1:(0.8-2).

[0016] In some embodiments, the maleic anhydride compatibilizer is selected from maleic anhydride-grafted polyethylene; preferably, the grafting rate of the maleic anhydride-grafted polyethylene is 0.5-1%. The grafting rate is determined by acid-base titration.

[0017] In some embodiments, the synergistic flame retardant is selected from at least one of triazine bromide and brominated epoxy. Triazine bromide is preferred.

[0018] In some embodiments, the crosslinking agent is selected from at least one of triallyl isocyanurate, trimethylolpropane triacrylate, and trimethylolpropane trimethacrylate.

[0019] The present invention may also incorporate conventional additives in the art, including but not limited to antioxidants and lubricants. Preferably, the present invention further includes 1-5 parts of antioxidant.

[0020] Optionally, the antioxidant is a primary antioxidant, or a primary antioxidant and a secondary antioxidant; specifically, the primary antioxidant is selected from at least one of primary antioxidant 1098, antioxidant 1790, or antioxidant 1010; the secondary antioxidant is selected from at least one of antioxidant 168, antioxidant 626, and RIANOX DSTDP.

[0021] This invention protects a method for preparing a halogen-free flame-retardant thermosetting polyolefin material, comprising the following steps: mixing the raw materials of each component evenly, melt extruding, granulating, and obtaining the halogen-free flame-retardant thermosetting polyolefin material.

[0022] In some embodiments, the twin-screw extruder has a barrel temperature of 200-300°C, a feeding capacity of 300-600 kg / h, and a screw speed of 300-600 r / min.

[0023] This invention protects a flame-retardant cable material comprising the aforementioned halogen-free flame-retardant thermosetting polyolefin material.

[0024] Compared with the prior art, the beneficial effects of the present invention are: This invention provides a halogen-free flame-retardant thermosetting polyolefin material, which uses a specific ratio of polyphenylene ether resin / styrene elastomer / polyethylene system and adds a specific type of halogen-free flame retardant to improve flame retardant performance without significantly damaging mechanical properties; at the same time, the material is easy to crosslink after irradiation, can meet the 125°C temperature resistance performance requirements specified by UL1581, and can pass the VW-1 flame retardant test. Detailed Implementation

[0025] The present invention will be further described below with reference to specific embodiments, but the embodiments do not limit the present invention in any way. Unless otherwise stated, the raw materials and reagents used in the embodiments of the present invention are conventionally purchased raw materials and reagents.

[0026] The raw materials for the examples and comparative examples are as follows: Polyphenylene ether resin: PPO-1: Intrinsic viscosity is 44 cm⁻¹ 3 / g, PPE LXN045C, Nantong Xingchen Synthetic Materials Co., Ltd.

[0027] PPO-2: Intrinsic viscosity is 41 cm⁻¹ 3 / g, PPE LXN040C, Nantong Xingchen Synthetic Materials Co., Ltd.

[0028] Styrene-based elastomers: SEBS-1: Styrene-ethylene-butene-styrene block copolymer, styrene content 33%, Kraton (USA), G1651.

[0029] SEBS-2: Styrene-ethylene-butene-styrene block copolymer, styrene content 21%, Kraton, USA, G1642.

[0030] Polyethylene: LDPE: Melt mass flow rate of 2.6 g / 10 min at 190℃ and 2.16 kg load, 2426H, CNOOC Shell; LLDPE: Melt mass flow rate of 2.2 g / 10min at 190℃ and 2.16 Kg load, Maoming Petrochemical Company, LLDPE 7042.

[0031] Compatibilizer: Maleic anhydride-grafted polyethylene, grafting rate 0.65%, MC218, Nengzhiguang.

[0032] Crosslinking agent: Trimethylolpropane trimethacrylate (TMPTMA), Guangzhou Coulson Chemical Co., Ltd.

[0033] Flame retardant: APP: Ammonium polyphosphate, APP-3, Zhenjiang Xingxing Flame Retardant Co., Ltd.

[0034] MCA: Melamine cyanurate, Shouguang Weidong Chemical Co., Ltd.

[0035] Magnesium hydroxide: ZH-H2-1, Wuxi Zehui Chemical Co., Ltd.

[0036] Synergistic Flame Retardant-1: Triazine Bromide, FR-245, Israel Chemicals.

[0037] Synergistic Flame Retardant-2: Brominated Epoxy, EP-25K, Jiangsu Xingsheng Chemical Co., Ltd.

[0038] Antioxidants: Antioxidant 1010, DSTDP and RIANOX MD-1024 in a mass ratio of 1:0.5:0.5, Tianjin Lianlong Technology Co., Ltd.

[0039] The following examples and comparative methods for preparing halogen-free flame-retardant thermosetting polyolefin materials include the following steps: mixing the raw materials of each component evenly, melt extruding, granulating, and obtaining the halogen-free flame-retardant thermosetting polyolefin material.

[0040] The twin-screw extruder has a barrel temperature of 200-300℃, a feeding capacity of 450 kg / h, and a screw speed of 450 r / min.

[0041] Examples 1-14 This embodiment provides a series of halogen-free flame-retardant thermosetting polyolefin materials, the components of which are shown in Table 1 by mass.

[0042] Table 1

[0043] Comparative Examples 1-9 This comparative example provides a series of halogen-free flame-retardant thermosetting polyolefin materials, the components of which by mass are shown in Table 2.

[0044] Table 2

[0045] Performance testing The halogen-free flame-retardant thermosetting polyolefin materials of the above embodiments and comparative examples were used to make cables under an electron beam irradiation dose of 10Mrad. The performance of the finished cables was tested, and the results are shown in Tables 3-4.

[0046] 1. Thermal elongation: Tested according to GB / T 2951.21-2008 standard; finished cable wall thickness is 0.5mm; required to meet thermal elongation ≤175%.

[0047] 2. VW-1 Test: Tested according to UL 1581-2011, with a cable sample outer diameter of 1.6mm. If a 1.6mm outer diameter cable sample fails the VW-1 (1.6mm) test, a 2.2mm outer diameter cable will be used for the retest. If the 2.2mm outer diameter cable fails the VW-1 (2.2mm) test, it will be considered unqualified.

[0048] 3. Tensile strength and elongation at break: The tensile strength and elongation at break of the finished cable are tested according to standard GB / T 1040.3-2006.

[0049] 4. High temperature aging: Test conditions: 180℃, 7 days; the tensile strength and elongation at break retention rate after aging should be greater than 80% according to standard GB / T 1040.3-2006.

[0050] Table 3

[0051] Table 4

[0052] " / " indicates that no further testing is required if the thermal elongation test or VW-1 test is not passed, or if the test is not meaningful due to breakage after aging.

[0053] The results show that the present invention provides a halogen-free flame-retardant thermosetting polyolefin material, which adopts a specific ratio of polyphenylene ether resin / styrene elastomer / polyethylene system and adds a specific type of halogen-free flame retardant to improve flame retardant performance without significantly damaging mechanical properties; specifically, its thermal elongation is ≤60%, and it passes the VW-1 (1.6mm / 2.2mm) test, with a tensile strength ≥14.7MPa, an elongation at break ≥337%, an aging tensile strength retention rate ≥81%, and an aging elongation at break retention rate ≥82%.

[0054] Compared to Example 1, Comparative Example 1, lacking PPO, failed the VW-1 test; the excessive PPO in Comparative Example 2 resulted in excessively high thermal elongation. In Comparative Example 3, the low elastomer content led to poor elongation at break performance; in Comparative Example 4, the excessive LDPE content caused fracture during the thermal elongation test, indicating extremely poor thermal stability; and Comparative Example 5, lacking a compatibilizer, also resulted in fracture during the thermal elongation test.

[0055] In Comparative Example 6, the excessive amount of flame retardant led to a decrease in mechanical properties; in Comparative Example 7, when Mg(OH)2 was used as the flame retardant, it failed the VW-1 test. Similarly, in Comparative Example 8, when no synergistic flame retardant was used, it also failed the VW-1 test.

[0056] The above embodiments of the present invention are merely examples for clearly illustrating the present invention and are not intended to limit the implementation of the present invention. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively describe all possible implementations here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A halogen-free flame-retardant thermosetting polyolefin material, characterized in that, Includes the following components by mass: 5-20 parts of polyphenylene ether resin, 20-40 parts of styrene elastomer 20-40 parts of polyethylene 5-16 parts of maleic anhydride compatibilizer 20-35 parts of halogen-free flame retardant 5-10 parts of synergistic flame retardant 1-3 parts of crosslinking agent; The halogen-free flame retardant is selected from ammonium polyphosphate and / or melamine cyanurate.

2. The halogen-free flame-retardant thermosetting polyolefin material according to claim 1, characterized in that, The halogen-free flame retardant is selected from ammonium polyphosphate and melamine cyanurate in a mass ratio of 1:(0.5-4).

3. The halogen-free flame-retardant thermosetting polyolefin material according to claim 1, characterized in that, The styrene-based elastomer is selected from styrene-ethylene-butene-styrene block copolymers; preferably, the styrene content in the styrene-based elastomer is 18-42 wt%.

4. The halogen-free flame-retardant thermosetting polyolefin material according to claim 1, characterized in that, The intrinsic viscosity of the polyphenylene ether resin is 32-45 cm⁻¹. 3 / g.

5. The halogen-free flame-retardant thermosetting material according to claim 1, characterized in that, The polyethylene is selected from LDPE and / or LLDPE; preferably, the polyethylene has a melt mass flow rate of 0.1-10 g / 10 min at 190°C and 2.16 kg load.

6. The halogen-free flame-retardant thermosetting polyolefin material according to claim 1, characterized in that, The maleic anhydride compatibilizer is selected from maleic anhydride-grafted polyethylene; preferably, the grafting rate of maleic anhydride-grafted polyethylene is 0.5-1%.

7. The halogen-free flame-retardant thermosetting polyolefin material according to claim 1, characterized in that, The synergistic flame retardant is selected from at least one of triazine bromide and brominated epoxy; preferably triazine bromide.

8. The halogen-free flame-retardant thermosetting polyolefin material according to claim 1, characterized in that, The crosslinking agent is selected from at least one of triallyl isocyanurate, trimethylolpropane triacrylate, and trimethylolpropane trimethacrylate.

9. A method for preparing a halogen-free flame-retardant thermosetting polyolefin material according to any one of claims 1-8, characterized in that, The process includes the following steps: mixing the raw materials of each component evenly, melting and extruding, and granulating to obtain the halogen-free flame-retardant thermosetting polyolefin material.

10. A flame-retardant cable material, characterized in that, The material comprises the halogen-free flame-retardant thermosetting polyolefin material according to any one of claims 1-8.

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