Polyphenyl ether composition and application thereof

Abstract

The invention discloses a polyphenyl ether composition which comprises polyphenyl ether, modified aluminum nitride, a cyclic phosphazene flame retardant and a compatilizer. The cyclic phosphazene flame retardant disclosed by the invention not only can be used as a high-efficiency flame retardant, but also can be used as a bridging agent of a heat-conducting network, and is preferentially adsorbed on the surfaces and gaps of aluminum nitride particles through the molecular structure of the cyclic phosphazene flame retardant, so that a high-efficiency molecular bridge is constructed between aluminum nitride, the interface thermal resistance is reduced, and meanwhile, the flame-retardant efficiency is improved. Through the synergistic effect of the modified aluminum nitride and the cyclic phosphazene flame retardant, the heat-conducting property and flame-retardant property of the polyphenyl ether composition are remarkably improved under the condition of lower total filler amount, and meanwhile, better mechanical property is maintained.

Description

Technical Field

[0001] This invention relates to the field of polyphenylene ether compositions, and more particularly to a polyphenylene ether composition with high thermal conductivity and high flame retardancy. Background Technology

[0002] Polyphenylene oxide (PPO), also known as polyphenylene oxide, is chemically named poly(2,6-dimethyl-1,4-phenylene ether). It possesses high heat resistance, excellent dimensional stability, low water absorption, and superior dielectric properties, making it widely used in electronics, automotive, and communications industries. However, with the development of cutting-edge technologies such as 5G communication and new energy vehicles, more stringent requirements have been placed on material performance, especially in terms of thermal management and safety. Specifically, in components such as battery modules for electric vehicles, motor control housings, and power amplifiers for 5G base stations, materials are required not only to be lightweight and high-strength, but also to dissipate heat quickly (high thermal conductivity) and prevent flame spread in extreme conditions (high flame retardancy). PPO itself has an extremely low thermal conductivity of approximately 0.2 W / m·K, and although it possesses some flame retardancy, it is difficult to meet the highest flame retardancy rating of UL94 V-0.

[0003] Currently, common modification methods involve adding thermally conductive fillers or flame retardants separately to PPO. Thermally conductive fillers include aluminum nitride and boron nitride; flame retardants include phosphorus-based and bromide-based flame retardants. However, these two methods exhibit a significant "seesaw" effect: achieving high thermal conductivity requires a large amount of thermally conductive filler, which leads to deterioration of material processing fluidity, a sharp decline in mechanical properties, especially impact toughness, and high costs. Conversely, adding large amounts of flame retardants disrupts the continuity of the matrix, further deteriorating mechanical properties and thermal conductivity pathways. Summary of the Invention

[0004] The main objective of this invention is to provide a polyphenylene ether composition that solves the problem that existing polyphenylene ether compositions cannot simultaneously satisfy the requirements of good thermal conductivity, flame retardancy, and mechanical properties.

[0005] The above-mentioned objective of this invention is achieved through the following technical solution: In a first aspect, the present invention provides a polyphenylene ether composition comprising, by weight, the following components: Polyphenylene oxide: 40-70 parts; Modified aluminum nitride: 20-40 parts; Cyclic phosphazene flame retardant: 5-15 parts; Compatibilizer: 2-8 parts.

[0006] In some embodiments of this application, the polyphenylene ether is 40-60 parts.

[0007] In some embodiments of this application, the intrinsic viscosity of the polyphenylene ether is 35-50 dL / g, and the molecular weight ranges from 22,000 to 57,000.

[0008] In some embodiments of this application, the modifier of the modified aluminum nitride is a silane coupling agent or a titanate coupling agent, and the mass ratio of the modifier to the aluminum nitride is (0.5-2.5):100.

[0009] In some embodiments of this application, the silane coupling agent is selected from at least one of aminosilanes containing aromatic rings, long-chain alkylsilanes, epoxy-containing silanes, or aminosilanes. And / or, the titanate coupling agent is a chelating titanate coupling agent.

[0010] In some embodiments of this application, the cyclic phosphazene flame retardant is selected from at least one of hexaphenoxycyclotriphosphazene, hexa(4-aldehyde phenoxy)cyclotriphosphazene, hexa(4-carboxyphenoxy)cyclotriphosphazene, or hexa(3-aminophenoxy)cyclotriphosphazene.

[0011] In some embodiments of this application, the compatibilizer is a styrene-maleic anhydride copolymer with a maleic anhydride grafting rate of 6-10% and a melt index of 8-15 g / 10min (200℃, 5kg); And / or, by weight, the polyphenylene ether composition further comprises 0.5-2 parts of antioxidant; the antioxidant is selected from at least one of hindered phenolic antioxidants, phosphite antioxidants, and thioether antioxidants; And / or, by weight, the polyphenylene ether composition further comprises 0.5-2 parts of lubricant; the lubricant is selected from at least one of fatty acid amide lubricants or metal soap lubricants.

[0012] In a second aspect, the present invention provides the application of the above-described polyphenylene ether composition in circuit board substrates, thermally conductive supports, heat dissipation housings, and wire and cable insulation layers.

[0013] The polyphenylene ether composition of this invention comprises polyphenylene ether, modified aluminum nitride, a cyclic phosphazene flame retardant, and a compatibilizer. The cyclic phosphazene flame retardant of this invention not only serves as a highly efficient flame retardant but also as a "bridging agent" for the thermally conductive network. Through its molecular structure, it preferentially adsorbs onto the surface and interstices of aluminum nitride particles, constructing efficient molecular bridges between the aluminum nitride particles, reducing interfacial thermal resistance, and simultaneously improving flame retardant efficiency. Through the synergistic effect of the modified aluminum nitride and the cyclic phosphazene flame retardant, the thermal conductivity and flame retardant properties of the polyphenylene ether composition are significantly improved with a relatively low total amount of aluminum nitride, while maintaining good mechanical properties. Detailed Implementation

[0014] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0015] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0016] In this invention, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Furthermore, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. If the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0017] Polyphenylene oxide (PPO), also known as polyphenylene oxide, is chemically named poly(2,6-dimethyl-1,4-phenylene ether). It possesses high heat resistance, excellent dimensional stability, low water absorption, and superior dielectric properties, making it widely used in electronics, automotive, and communications industries. However, with the development of cutting-edge technologies such as 5G communication and new energy vehicles, more stringent requirements have been placed on material performance, especially in terms of thermal management and safety. Specifically, in components such as battery modules for electric vehicles, motor control housings, and power amplifiers for 5G base stations, materials are required not only to be lightweight and high-strength, but also to dissipate heat quickly (high thermal conductivity) and prevent flame spread in extreme conditions (high flame retardancy). PPO itself has an extremely low thermal conductivity of approximately 0.2 W / m·K, and although it possesses some flame retardancy, it is difficult to meet the highest flame retardancy rating of UL94 V-0.

[0018] Currently, common modification methods involve adding thermally conductive fillers or flame retardants separately to PPO. Thermal fillers include aluminum nitride and boron nitride; flame retardants include phosphorus-based and bromide-based flame retardants. However, these two methods exhibit a significant "seesaw" effect: achieving high thermal conductivity requires a large amount of thermally conductive filler, which leads to deterioration of material processing fluidity, a sharp decline in mechanical properties, especially impact toughness, and high costs. Conversely, adding large amounts of flame retardants disrupts the continuity of the matrix, further deteriorating mechanical properties and thermal conductivity pathways.

[0019] Based on this, in a first aspect, the present invention provides a polyphenylene ether composition, comprising the following components by weight: Polyphenylene oxide: 40-70 parts; Modified aluminum nitride: 20-40 parts; Cyclic phosphazene flame retardant: 5-15 parts; Compatibilizer: 2-8 parts.

[0020] Understandably, modified aluminum nitride significantly improves the interfacial bonding strength between aluminum nitride and polyphenylene ether (PPO), reduces interfacial thermal resistance, and improves the dispersion of the modified aluminum nitride thermally conductive filler in the matrix. Simultaneously, the modified aluminum nitride can better construct a thermally conductive network in the PPO matrix, improving the thermal conductivity of the PPO polymer while maintaining good mechanical properties. Cyclic phosphazene flame retardants are small molecule compounds with poor compatibility with PPO, easily migrating and precipitating during processing and use, leading to decreased flame retardant effect and blooming on the material surface. Through the action of compatibilizers, the thermally conductive filler and flame retardant form a more efficient thermally conductive network and flame retardant synergistic system in the PPO matrix, achieving simultaneous improvement in thermal conductivity and flame retardant properties. At the same time, compatibilizers can improve melt flowability and enhance the processing and molding properties of the material.

[0021] Understandably, polyphenylene ether can be in any number of parts between 40 and 70, such as 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, 60, 62, 64, 66, 68, and 70; modified aluminum nitride can be in any number of parts between 20 and 40, such as 20, 22, 24, 26, 28, 30, 32, 34, 36, and 40; cyclic phosphazene flame retardant can be in any number of parts between 5 and 15, such as 5, 7, 9, 11, 13, and 15; and compatibilizer can be in any number of parts between 2 and 8, such as 2, 3, 4, 5, 6, 7, and 8.

[0022] The polyphenylene ether composition of this invention comprises polyphenylene ether, modified aluminum nitride, a cyclic phosphazene flame retardant, and a compatibilizer. The cyclic phosphazene flame retardant of this invention not only serves as a highly efficient flame retardant but also as a "bridging agent" for the thermally conductive network. Through its molecular structure, it preferentially adsorbs onto the surface and interstices of aluminum nitride particles, constructing efficient molecular bridges between the aluminum nitride particles, reducing interfacial thermal resistance, and simultaneously improving flame retardant efficiency. Through the synergistic effect of the modified aluminum nitride and the cyclic phosphazene flame retardant, the thermal conductivity and flame retardant properties of the polyphenylene ether composition are significantly improved with a relatively low total filler content, while maintaining good mechanical properties.

[0023] In some embodiments, the polyphenylene ether is 40-60 parts.

[0024] Understandably, polyphenylene ether (PPE) can be present in any number of parts between 40 and 60, such as 40, 42, 44, 46, 48, 50, 52, 54, 56, 58, and 60 parts by weight. This 40-60 parts by weight of PPE ensures, on the one hand, sufficient to form a continuous matrix to provide good mechanical properties and processing flowability; on the other hand, it provides a better spatial distribution for a high proportion of aluminum nitride, enabling the construction of an efficient three-dimensional thermally conductive and flame-retardant network, thereby synergistically achieving good thermal conductivity and flame retardancy rating in the material.

[0025] In some embodiments, the polyphenylene ether has an intrinsic viscosity of 35-50 dL / g and a molecular weight range of 22,000-57,000.

[0026] Understandably, polyphenylene ether has an intrinsic viscosity of 35-50 dL / g and a molecular weight range of 22,000-57,000. This not only provides suitable shear force for the processing, ensuring its smoothness, but also guarantees the intrinsic strength, rigidity, and heat resistance of the polyphenylene ether composition.

[0027] In some embodiments, the modifier of the modified aluminum nitride is a silane coupling agent or a titanate coupling agent, and the mass ratio of the modifier to the aluminum nitride is (0.5-2.5):100.

[0028] In some embodiments, the silane coupling agent is selected from at least one of aminosilanes containing aromatic rings, long-chain alkylsilanes, epoxy-containing silanes, or aminosilanes. And / or, the titanate coupling agent is a chelating titanate coupling agent.

[0029] Understandably, aromatic ring-containing aminosilanes are N-phenyl-γ-aminopropyltrimethoxysilane; long-chain alkylsilanes are octadecyltrimethoxysilane and octyltriethoxysilane; epoxy-containing silanes are γ-(2,3-epoxypropoxy)propyltrimethoxysilane, abbreviated as KH-560; and aminosilanes are γ-aminopropyltriethoxysilane, abbreviated as KH-550. Specifically, taking KH-550 as an example of a silane coupling agent, the preparation process of modified aluminum nitride is as follows: Aluminum nitride powder pretreatment: Place aluminum nitride powder in a drying oven to remove surface adsorbed water and expose more active hydroxyl groups; Silane hydrolysis: Deionized water and anhydrous ethanol are mixed in a certain proportion, and the pH is adjusted to 4-5 with acetic acid. Hydrolysis produces silanol Si-OH. The hydrolyzed silanols react with the hydroxyl groups on the aluminum nitride surface to form Si-O-Al covalent bonds, and the silanols also undergo dehydration condensation. Thus, silanes are grafted onto the surface of the aluminum nitride filler. Filtration removes excess silane and byproducts.

[0030] Understandably, titanate coupling agents are chelating titanate coupling agents, containing groups in their molecules that form chelate rings with titanium atoms, such as oxyacetic acid groups, ethylene glycol groups, etc. Preferably, they are at least one of triisostearoyl titanate isopropyl or bis(dioctylpyrophosphate)oxyacetate titanium.

[0031] In some embodiments, the cyclic phosphazene flame retardant is selected from at least one of hexaphenoxycyclotriphosphazene, hexa(4-aldehyde phenoxy)cyclotriphosphazene, hexa(4-carboxyphenoxy)cyclotriphosphazene, or hexa(3-aminophenoxy)cyclotriphosphazene.

[0032] Understandably, cyclotriphosphazenes are a special class of compounds that fall between organic and inorganic compounds. Their main chain is a six-membered ring composed of alternating single and double bonds of phosphorus and nitrogen atoms. The difference between different cyclotriphosphazenes lies in the type and number of substituent side chains on the phosphorus atom. Hexaphenoxycyclotriphosphazenes have six phenoxy groups on the phosphorus atom as substituent side chains; hexa(4-aldehydephenoxy)cyclotriphosphazenes have six 4-aldehydephenoxy groups on the phosphorus atom as substituent side chains; hexa(4-carboxyphenoxy)cyclotriphosphazenes have six 4-carboxyphenoxy groups on the phosphorus atom as substituent side chains; and hexa(3-aminophenoxy)cyclotriphosphazenes have six 3-aminophenoxy groups on the phosphorus atom as substituent side chains.

[0033] Understandably, during combustion, cyclotriphosphazene decomposes upon heating to form oxyacids of phosphorus, such as phosphoric acid, metaphosphoric acid, and polyphosphoric acid, which coat the surface of the polymer material. This oxyacid acts as a flame retardant by isolating and diluting flammable and combustion-supporting gases in the air. Simultaneously, the gaseous products formed by thermal decomposition contain PO·, which inhibits the production of H· and OH·, thus achieving a flame-retardant effect. Furthermore, it decomposes to produce non-flammable gases such as NH3, CO2, and NO, diluting oxygen in the air and flammable gases produced by polymer decomposition. Moreover, the nitrogen oxides produced can capture free radicals, thereby inhibiting the combustion reaction. The oxyacids of phosphorus formed by thermal decomposition, together with the produced non-flammable gases, block air flow, terminating free radical chain reactions and exerting a synergistic effect of phosphorus and nitrogen. The phenoxy substituents on the cyclic phosphazene have benzene rings and ether bond oxygen atoms, which can interact with surface-modified aluminum nitride through π-π stacking, van der Waals forces, and hydrogen bonds, resulting in specific adsorption and bonding. This allows phosphazene molecules to preferentially and stably accumulate on the surface and interstices of aluminum nitride. At the same time, polar groups such as amino, aldehyde, and carboxyl groups can also enhance the binding with aluminum nitride through adsorption, thereby constructing efficient molecular bridges between aluminum nitride molecules and significantly reducing interfacial thermal resistance. Furthermore, during combustion, a stable barrier layer can be formed in situ on the thermally conductive network framework, achieving a deep synergy between thermal conductivity and flame retardancy.

[0034] In some embodiments, the compatibilizer is a styrene-maleic anhydride copolymer with a maleic anhydride grafting rate of 6-10% and a melt index of 8-15 g / 10min (200°C, 5 kg); And / or, by weight, the polyphenylene ether composition further comprises 0.5-2 parts of antioxidant; the antioxidant is selected from at least one of hindered phenolic antioxidants, phosphite antioxidants, and thioether antioxidants; And / or, by weight, the polyphenylene ether composition further comprises 0.5-2 parts of lubricant; the lubricant is selected from at least one of fatty acid amide lubricants or metal soap lubricants.

[0035] Understandably, styrene-maleic anhydride copolymer (SMA) can reduce the interfacial tension between the filler and the matrix, promote the uniform dispersion of aluminum nitride in the PPO matrix, reduce agglomeration, and improve thermal conductivity.

[0036] Understandably, antioxidants can interrupt the oxidation chain reaction by capturing free radicals and decomposing peroxides, thus effectively preventing the thermal and oxidative aging of PPO during processing and long-term use, and maintaining the material's mechanical properties, color stability, and service life.

[0037] Understandably, the main function of lubricants is to improve the processing flowability and demolding performance of polymers. In PPO extrusion, injection molding, and other processing, lubricants can reduce the coefficient of friction between the melt and the metal surface of the equipment, reduce melt viscosity, improve processing efficiency, and at the same time prevent the melt from adhering to the mold surface, ensuring smooth demolding of the product.

[0038] In a second aspect, the present invention provides the application of the above-described polyphenylene ether composition in circuit board substrates, thermally conductive supports, heat dissipation housings, and wire and cable insulation layers.

[0039] The present invention will be further described in detail below with reference to specific embodiments.

[0040] Example 1 Please refer to Tables 1 and 2. The polyphenylene ether composition of this embodiment includes the following components by weight: Polyphenylene ether 1:40 parts; N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride: 40 parts; Hexaphenoxycyclotriphosphazene: 15 parts; SMA: 8 copies Antioxidant 1010: 1 part; Zinc stearate: 1 part.

[0041] The preparation method of modified aluminum nitride is as follows: Preparation of ethanol solution: 150 parts anhydrous ethanol, 5 parts deionized water, and glacial acetic acid were used to adjust the pH value to 4-5 to obtain an ethanol solution.

[0042] Hydrolysis of N-phenyl-γ-aminopropyltrimethoxysilane: Dissolve 1 part of N-phenyl-γ-aminopropyltrimethoxysilane in the above ethanol solution to obtain a hydrolysate of the silane coupling agent; Preparation of modified aluminum nitride: The hydrolysate of the silane coupling agent obtained above was slowly added to 100 parts of pretreated aluminum nitride powder to obtain N-phenyl-γ-aminopropyltrimethoxysilane modified aluminum nitride.

[0043] The test strip preparation method is as follows: Initial mixing: Place the polyphenylene ether 1, N-phenyl-γ-aminopropyltrimethoxysilane modified aluminum nitride, hexaphenoxycyclotriphosphazene, SMA, antioxidant 1010 and zinc stearate in a high-speed mixer and mix for 15-30 minutes to obtain the premix. Melt blending: The above premixed material is fed into a twin-screw extruder for melt blending, extrusion, cooling, and granulation. The temperature of zones one through ten of the extruder is set at 240-290℃, and the screw speed is 100-200 rpm. Injection molding: The obtained granules are dried at 100℃ for 4-6 hours, and then injection molded into standard test strips by an injection molding machine.

[0044] Example 2 The formulation of the polyphenylene ether composition, the preparation method of N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride, and the preparation method of the test strips in this embodiment are basically the same as those in Example 1. The difference lies in the mass fractions of each component, as shown in Tables 1 and 2. The polyphenylene ether composition in this embodiment, by weight, includes the following components: Polyphenylene ether 1:50 parts; N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride: 30 parts; Hexaphenoxycyclotriphosphazene: 10 parts; SMA: 5 copies Antioxidant 1010: 1 part; Zinc stearate: 1 part.

[0045] Example 3 The formulation of the polyphenylene ether composition, the preparation method of N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride, and the preparation method of the test strips in this embodiment are basically the same as those in Example 1. The difference lies in the mass fractions of each component, as shown in Tables 1 and 2. The polyphenylene ether composition in this embodiment, by weight, includes the following components: Polyphenylene ether 1: 60 parts; N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride: 20 parts; Hexaphenoxycyclotriphosphazene: 5 parts; SMA: 2 copies Antioxidant 1010: 1 part; Zinc stearate: 1 part.

[0046] Example 4 The formulation of the polyphenylene ether composition, the preparation method of N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride, and the preparation method of the test strips in this embodiment are basically the same as those in Example 1. The difference lies in the mass fractions of each component, as shown in Tables 1 and 2. The polyphenylene ether composition in this embodiment, by weight, includes the following components: Polyphenylene ether 1: 70 parts; N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride: 30 parts; Hexaphenoxycyclotriphosphazene: 10 parts; SMA: 5 copies Antioxidant 1010: 1 part; Zinc stearate: 1 part.

[0047] Example 5 The formulation of the polyphenylene ether composition and the preparation method of the test strips in this embodiment are basically the same as those in Example 2, except that the aluminum nitride modified by N-phenyl-γ-aminopropyltrimethoxysilane is replaced by aluminum nitride modified by octyltriethoxysilane. Please refer to Tables 1 and 2. The polyphenylene ether composition in this embodiment includes the following components by weight: Polyphenylene ether 1:50 parts; 30 parts of aluminum nitride modified with octyltriethoxysilane; Hexaphenoxycyclotriphosphazene: 10 parts; SMA: 5 copies Antioxidant 1010: 1 part; Zinc stearate: 1 part.

[0048] The preparation method of modified aluminum nitride is as follows: Preparation of ethanol solution: 150 parts anhydrous ethanol, 5 parts deionized water, and glacial acetic acid were used to adjust the pH value to 4-5 to obtain an ethanol solution.

[0049] Hydrolysis of octyltriethoxysilane: 1.2 parts of octyltriethoxysilane were dissolved in the above ethanol solution to obtain the hydrolysate of the silane coupling agent; Preparation of modified aluminum nitride: The hydrolysate of the silane coupling agent obtained above was slowly added to 100 parts of pretreated aluminum nitride powder to obtain aluminum nitride with octyltriethoxysilane surface modification.

[0050] Example 6 The formulation of the polyphenylene ether composition, the preparation method of N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride, and the preparation method of the test strips in this embodiment are basically the same as those in Example 2, except that hexaphenoxycyclotriphosphazene is replaced with hexa(3-aminophenoxy)cyclotriphosphazene. Please refer to Tables 1 and 2. The polyphenylene ether composition in this embodiment includes the following components by weight: Polyphenylene ether 1:50 parts; N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride: 30 parts; Hexa(3-aminophenoxy)cyclotriphosphazene: 10 parts; SMA: 5 copies Antioxidant 1010: 1 part; Zinc stearate: 1 part.

[0051] Example 7 The formulation of the polyphenylene ether composition, the preparation method of N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride, and the preparation method of the test strips in this embodiment are basically the same as those in Example 2, except that polyphenylene ether 1 is replaced with polyphenylene ether 2. Please refer to Tables 1 and 2. The polyphenylene ether composition in this embodiment includes the following components by weight: Polyphenylene ether 2: 50 parts; N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride: 30 parts; Hexaphenoxycyclotriphosphazene: 10 parts; SMA: 5 copies Antioxidant 1010: 1 part; Zinc stearate: 1 part.

[0052] Comparative Example 1 The formulation of the polyphenylene ether composition in this comparative example and the preparation method of the test strips are basically the same as those in Example 2, except that N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride was not added. Please refer to Tables 1 and 2.

[0053] Comparative Example 2 The formulation of the polyphenylene ether composition, the preparation method of N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride, and the preparation method of the test strips in this comparative example are basically the same as those in Example 2, except that the amount of N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride is changed from 30 parts to 10 parts. Please refer to Tables 1 and 2. The polyphenylene ether composition of this example includes the following components by weight: Polyphenylene ether 1:50 parts; N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride: 10 parts; Hexaphenoxycyclotriphosphazene: 10 parts; SMA: 5 copies Antioxidant 1010: 1 part; Zinc stearate: 1 part.

[0054] Comparative Example 3 The formulation of the polyphenylene ether composition in this comparative example, the preparation method of the N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride, and the preparation method of the test strips are basically the same as those in Example 2, except that the amount of N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride is changed from 30 parts to 55 parts. Please refer to Tables 1 and 2. The polyphenylene ether composition in this example includes the following components by weight: Polyphenylene ether 1:50 parts; N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride: 55 parts; Hexaphenoxycyclotriphosphazene: 10 parts; SMA: 5 copies Antioxidant 1010: 1 part; Zinc stearate: 1 part.

[0055] Comparative Example 4 The formulation of the polyphenylene ether composition, the preparation method of N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride, and the preparation method of the test strips in this comparative example are basically the same as those in Example 2, except that hexaphenoxycyclotriphosphazene was not added. Please refer to Tables 1 and 2.

[0056] Comparative Example 5 The formulation of the polyphenylene ether composition in this comparative example, the preparation method of the N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride, and the preparation method of the test strip are basically the same as those in Example 2, except that the amount of hexaphenoxycyclotriphosphazene is changed from 10 parts to 3 parts. Please refer to Tables 1 and 2. The polyphenylene ether composition in this example includes the following components by weight: Polyphenylene ether 1:50 parts; N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride: 30 parts; Hexaphenoxycyclotriphosphazene: 3 parts; SMA: 5 copies Antioxidant 1010: 1 part; Zinc stearate: 1 part.

[0057] Comparative Example 6 The formulation of the polyphenylene ether composition, the preparation method of N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride, and the preparation method of the test strips in this comparative example are basically the same as those in Example 2, except that the number of hexaphenoxycyclotriphosphazene parts is changed from 10 parts to 22 parts. Please refer to Tables 1 and 2. The polyphenylene ether composition of this example includes the following components by weight: Polyphenylene ether 1:50 parts; N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride: 30 parts; Hexaphenoxycyclotriphosphazene: 22 parts; SMA: 5 copies Antioxidant 1010: 1 part; Zinc stearate: 1 part.

[0058] Comparative Example 7 The formulation and test strip preparation method of the polyphenylene ether composition in this comparative example are basically the same as those in Example 2, except that the aluminum nitride modified with N-phenyl-γ-aminopropyltrimethoxysilane is replaced with unmodified aluminum nitride. Please refer to Tables 1 and 2. The polyphenylene ether composition in this example includes the following components by weight: Polyphenylene ether 1:50 parts; Unmodified aluminum nitride: 30 parts; Hexaphenoxycyclotriphosphazene: 10 parts; SMA: 5 copies Antioxidant 1010: 1 part; Zinc stearate: 1 part.

[0059] Comparative Example 8 The formulation of the polyphenylene ether composition in this comparative example, the preparation method of the N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride, and the preparation method of the test strips are basically the same as those in Example 2, except that hexaphenoxycyclotriphosphazene is replaced with triphenyl phosphate. Please refer to Tables 1 and 2. The polyphenylene ether composition in this example includes the following components by weight: Polyphenylene ether 1:50 parts; N-phenyl-γ-aminopropyltrimethoxysilane-modified aluminum nitride: 30 parts; Triphenyl phosphate: 10 parts; SMA: 5 copies Antioxidant 1010: 1 part; Zinc stearate: 1 part.

[0060] The test specimens of the above embodiments and comparative examples were used to determine the thermal conductivity, flame retardancy rating, notched impact strength, tensile properties, and flexural properties, according to the following test standards: (1) Thermal conductivity: Refer to standard ASTM D5470-2017. Inject the material into flat plate specimens (circular or square plates with a diameter or side length large enough to cover the heating and cooling areas of the tester) with thicknesses of 1.0 mm, 2.0 mm, and 3.0 mm. Using an HFM 436 steady-state heat flux thermal conductivity meter, place the sample between two plates at different temperatures, start the loading system, apply pressure to ensure close contact between the sample and the plates. Set the average temperature to 50°C and the constant clamping pressure to 0.50 MPa. Start the heating and cooling systems to allow the system to reach thermal equilibrium. Monitor the heat flux sensor and temperature readings. When the heat flux and temperature change within ±1% for 10 consecutive minutes, the system is considered to be in a steady state. At this time, record the heat flux density, sample thickness, and temperature difference, and finally calculate the thermal conductivity based on the above data.

[0061] (2) Flame retardancy rating: Refer to standard UL94. The material is injection molded into a 1.6mm thick sample. The vertical burning method is used. The material is placed vertically above the flame and burned with a specific flame. The afterflame time and whether the dripping material ignites the cotton wool are recorded to determine the flame retardancy rating of the material.

[0062] (3) Notched impact strength: Refer to standard ASTM D256. Inject the material into a specimen with dimensions of 80 mm long × 10 mm wide × 4 mm thick. Make a U-shaped notch in the center of one side of the specimen along its length. Using an IT503 pendulum impact testing machine, fix the specimen with the standard U-shaped notch horizontally and impact it with a pendulum. After the specimen breaks, read the energy absorbed during fracture from the display screen of the testing machine. Observe and record the fracture type of the specimen. Repeat the test on at least 5 specimens and calculate the notched impact strength value.

[0063] (4) Tensile properties: Refer to standard ASTM D638. The material was injection molded into a type I dumbbell specimen (gauge length 50 mm, thickness 3.2 mm). The tensile strength, elongation at break and tensile modulus were obtained by using a GT-AI-7000S electronic universal testing machine at a tensile rate of 5 mm / min. The stress-strain curve was recorded simultaneously. The testing software automatically calculated and obtained the tensile strength, elongation at break and tensile modulus.

[0064] (5) Bending performance: Referring to standard ASTM D790, the three-point bending test method was used. The material was injection molded into a specimen with a length of 127 mm, a width of 12.7 mm, and a thickness of 3.2 mm. An Instron 3400 series universal testing machine was used, equipped with a 2810-400 type three-point bending fixture (support span 51 mm), and the test was conducted at room temperature. Method A (strain rate 0.01 min) was adopted. -1The test speed is approximately 1.4 mm / min. The deflection at the midpoint of the specimen is measured directly using a deflectometer conforming to ASTM E83 B-2 accuracy. The load-deflection curve is recorded, and the flexural strength and flexural modulus of the material are calculated. At least five specimens are tested for each material, and the results are averaged.

[0065] Table 1. Manufacturer's name and parameters of each raw material in the polyphenylene ether compositions of the examples and comparative examples.

[0066] Table 2. Composition and mass fractions of each raw material in the polyphenylene ether compositions of the examples and comparative examples.

[0067]

[0068] Table 3 Test results of test strips prepared in the examples and comparative examples

[0069] As shown in Tables 1, 2, and 3, the test specimens prepared in Examples 1 to 7 have a thermal conductivity of 1.5-2.8 W / m·K, a flame retardancy rating of V-0, a notched impact strength of 10-19 kJ / m², a tensile strength of 87-112 MPa, an elongation at break of 32.7-61.2%, a tensile modulus of 3.2-5.6 GPa, a flexural strength of 106-152 MPa, and a flexural modulus of 3.1-5.9 GPa. This indicates that the test specimens prepared in Examples 1 to 8 have good thermal conductivity, flame retardancy, and mechanical properties.

[0070] Compared with Example 2, Comparative Examples 1 and 4 show the following differences: Comparative Example 1, without the addition of modified aluminum nitride, has a thermal conductivity of 0.23 W / m·K, a flame retardancy rating of "burning," a notched impact strength of 15 kJ / m², a tensile strength of 73 MPa, an elongation at break of 77.8%, a tensile modulus of 2.4 GPa, a flexural strength of 87 MPa, and a flexural modulus of 2.7 GPa; Comparative Example 4, without the addition of cyclic phosphazene flame retardant, has a thermal conductivity of 1.6 W / m·K, a flame retardancy rating of "burning," a notched impact strength of 15 kJ / m², a tensile strength of 93 MPa, an elongation at break of 45.2%, a tensile modulus of 4.2 GPa, a flexural strength of 128 MPa, and a flexural modulus of 4.6 GPa; and Example 2, with the addition of both modified aluminum nitride and cyclic phosphazene flame retardant, has a thermal conductivity of 2.4 W / m·K. With a W / m·K ratio, a flame retardant rating of V-0, a notched impact strength of 16 kJ / m², a tensile strength of 97 MPa, an elongation at break of 53.3%, a tensile modulus of 4.3 GPa, a flexural strength of 132 MPa, and a flexural modulus of 4.9 GPa, it can be seen that the modified aluminum nitride and the cyclic phosphazene flame retardant have a synergistic effect on the thermal conductivity and flame retardant properties of the polyphenylene ether composition, significantly improving the thermal conductivity and flame retardant properties while maintaining good mechanical properties.

[0071] Compared with Example 2, Comparative Examples 1, 2, and 3 showed the following differences: Comparative Example 1, without the addition of modified aluminum nitride, had a thermal conductivity of 0.23 W / m·K, a flame retardancy rating of "burning," a notched impact strength of 15 kJ / m², a tensile strength of 73 MPa, an elongation at break of 77.8%, a tensile modulus of 2.4 GPa, a flexural strength of 87 MPa, and a flexural modulus of 2.7 GPa; Comparative Example 2, with the addition of 10 parts of modified aluminum nitride, had a thermal conductivity of 1.1 W / m·K, a flame retardancy rating of V-1, a notched impact strength of 17 kJ / m², a tensile strength of 88 MPa, an elongation at break of 79.4%, a tensile modulus of 3 GPa, a flexural strength of 114 MPa, and a flexural modulus of 3.6 GPa; and Comparative Example 3, with the addition of 55 parts of modified aluminum nitride, had a thermal conductivity of 2.7 W / m·K. The material exhibits the following characteristics: W / m·K, flame retardant rating V-0, notched impact strength 8 kJ / m², tensile strength 102 MPa, elongation at break 15.7%, tensile modulus 6.1 GPa, flexural strength 142 MPa, and flexural modulus 6.2 GPa. It is evident that a low modified aluminum nitride content reduces the amount of cyclic phosphazene flame retardants adsorbed onto the aluminum nitride, hindering the formation of efficient molecular bridges between aluminum nitride molecules. This results in a significant decrease in thermal conductivity and overall performance. Furthermore, the lack of a synergistic effect between modified aluminum nitride and cyclic phosphazene flame retardants also reduces the material's flame retardant properties. Conversely, a high modified aluminum nitride content increases the amount of cyclic phosphazene flame retardants adsorbed onto the aluminum nitride, leading to more molecular bridges and a significant reduction in interfacial thermal resistance, thus improving both thermal conductivity and flame retardant properties. However, excessive aluminum nitride content can worsen the material's processing fluidity and drastically decrease its mechanical properties.

[0072] Compared with Example 2, Comparative Examples 4, 5, and 6 showed the following differences: Comparative Example 4, without the addition of cyclic phosphazene flame retardant, had a thermal conductivity of 1.6 W / m·K, a flame retardancy rating of "burning," a notched impact strength of 15 kJ / m², a tensile strength of 93 MPa, an elongation at break of 45.2%, a tensile modulus of 4.2 GPa, a flexural strength of 128 MPa, and a flexural modulus of 4.6 GPa; Comparative Example 5, with the addition of 3 parts of cyclic phosphazene flame retardant, had a thermal conductivity of 1.9 W / m·K, a flame retardancy rating of V-1, a notched impact strength of 15 kJ / m², a tensile strength of 95 MPa, an elongation at break of 52.0%, a tensile modulus of 3.5 GPa, a flexural strength of 120 MPa, and a flexural modulus of 4.0 GPa; and Comparative Example 6, with the addition of 22 parts of cyclic phosphazene flame retardant, had a thermal conductivity of 1.8 W / m·K. The sample exhibits a W / m·K ratio, a flame retardant rating of V-0, a notched impact strength of 13 kJ / m², a tensile strength of 85 MPa, an elongation at break of 39.9%, a tensile modulus of 3.7 GPa, a flexural strength of 118 MPa, and a flexural modulus of 4.2 GPa. This demonstrates that neither excessively low nor excessively high levels of cyclic phosphazene flame retardant can achieve a synergistic effect with modified aluminum nitride, failing to simultaneously improve both the thermal conductivity and flame retardant properties of the test sample, resulting in a deterioration in both properties.

[0073] Compared to Example 2, the test specimen prepared using unmodified aluminum nitride instead of modified aluminum nitride in Comparative Example 7 had a thermal conductivity of 1.3 W / m·K, a flame retardancy rating of V-1, a notched impact strength of 12 kJ / m², a tensile strength of 87 MPa, an elongation at break of 31.3%, a tensile modulus of 3 GPa, a flexural strength of 99 MPa, and a flexural modulus of 3.8 GPa. This demonstrates that unmodified aluminum nitride exhibits poor dispersion in the polyphenylene ether matrix, failing to construct a suitable thermally conductive network, resulting in reduced thermal conductivity and mechanical properties of the polyphenylene ether polymer.

[0074] Compared to Example 2, the test specimen prepared using triphenyl phosphate instead of cyclic phosphazene flame retardant in Comparative Example 8 had a thermal conductivity of 1.4 W / m·K, a flame retardancy rating of V-1, a notched impact strength of 14 kJ / m², a tensile strength of 92 MPa, an elongation at break of 49.6%, a tensile modulus of 4.0 GPa, a flexural strength of 127 MPa, and a flexural modulus of 4.2 GPa. This demonstrates that ordinary phosphorus-containing flame retardants cannot specifically adsorb and bond with surface-modified aluminum nitride, cannot accumulate on the surface and in the gaps between aluminum nitride particles, and cannot build molecular bridges between aluminum nitride particles, resulting in a decrease in thermal conductivity.

[0075] The above are merely preferred embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A polyphenylene ether composition, characterized in that, By weight, it includes the following ingredients: Polyphenylene oxide: 40-70 parts; Modified aluminum nitride: 20-40 parts; Cyclic phosphazene flame retardant: 5-15 parts; Compatibilizer: 2-8 parts.

2. The polyphenylene ether composition according to claim 1, characterized in that, The polyphenylene ether is 40-60 parts.

3. The polyphenylene ether composition according to claim 1, characterized in that, The intrinsic viscosity of the polyphenylene ether is 35-50 dL / g, and the molecular weight ranges from 22,000 to 57,000.

4. The polyphenylene ether composition according to claim 1, characterized in that, The modifier of the modified aluminum nitride is a silane coupling agent or a titanate coupling agent, and the mass ratio of the modifier to the aluminum nitride is (0.5-2.5):

100.

5. The polyphenylene ether composition according to claim 4, characterized in that, The silane coupling agent is selected from at least one of aminosilanes containing aromatic rings, long-chain alkylsilanes, epoxy-containing silanes, or aminosilanes. And / or, the titanate coupling agent is a chelating titanate coupling agent.

6. The polyphenylene ether composition according to claim 1, characterized in that, The cyclic phosphazene flame retardant is selected from at least one of hexaphenoxycyclotriphosphazene, hexa(4-aldehyde phenoxy)cyclotriphosphazene, hexa(4-carboxyphenoxy)cyclotriphosphazene, or hexa(3-aminophenoxy)cyclotriphosphazene.

7. The polyphenylene ether composition according to claim 1, characterized in that, The compatibilizer is a styrene-maleic anhydride copolymer with a maleic anhydride grafting rate of 6-10% and a melt index of 8-15 g / 10min (200℃, 5kg); And / or, by weight, the polyphenylene ether composition further comprises 0.5-2 parts of antioxidant; the antioxidant is selected from at least one of hindered phenolic antioxidants, phosphite antioxidants, and thioether antioxidants; And / or, by weight, the polyphenylene ether composition further comprises 0.5-2 parts of lubricant; the lubricant is selected from at least one of fatty acid amide lubricants or metal soap lubricants.

8. The application of the polyphenylene ether composition according to claim 1 in circuit board substrates, thermally conductive supports, heat dissipation housings, and wire and cable insulation layers.

Images