A low dielectric constant glass fiber reinforced polyphenylene ether composition and its preparation method and application

Abstract

The present invention relates to a polyphenylene ether composition, and specifically to a low dielectric constant glass fiber reinforced polyphenylene ether composition and its preparation method and application, including the following components by mass content: polyphenylene ether 25-60%; low dielectric constant low loss glass fiber 10-40%; inorganic filler 0.1-50%; processing aid 0.1-10%; low dielectric constant low loss glass fiber under 1MHz conditions, the dielectric constant is less than 3.8 and the dielectric loss is less than 0.001; the surface of the low dielectric constant low loss glass fiber is covered with carbon-doped silicon oxide as a coupling agent. Compared with the prior art, the present invention solves the problems of high processing difficulty, insufficient batch stability and high hygroscopicity of polyphenylene sulfide resin compositions in the prior art. The glass fiber of this scheme has good bonding with polyphenylene ether, which can give full play to the performance advantages of polyphenylene ether itself and effectively reduce the water absorption rate of the composition, with high overall production efficiency and excellent product quality.

Description

Technical Field

[0001] The invention relates to a polyphenylene ether composition, in particular to a low dielectric constant glass fiber reinforced polyphenylene ether composition and a preparation method and application thereof. Background Art

[0002] With the advent of the 5G era, mankind has entered a new era of communication revolution. The main features of the 5G era are high speed, low power consumption and low latency; the most important feature is ultra-fast data processing and transmission. The 5G era is not limited to mobile phone communications. From smart cities to driverless cars, high speed, low power consumption and low latency are required. Therefore, the 5G era has put forward higher requirements for the new generation of printed circuit boards (PCBs), and the new generation of printed circuit boards should focus on high speed and high frequency characteristics. In order to meet this performance of printed circuit boards, materials with low dielectric constant and low dielectric loss are particularly important under high frequency conditions.

[0003] The reinforced materials of printed circuit board substrates are glass fiber and resin. Generally speaking, when AC current flows through glass material, the glass material absorbs the current flow in a heat-absorbing manner. The absorbed dielectric loss energy depends on the dielectric constant and dielectric tangent of the glass material used, and the dielectric loss energy is proportional to the dielectric constant and dielectric tangent, respectively, and is generally expressed by the following formula: W = KfV2 × εtanδ; where W is the dielectric loss energy, K is a constant, f is a frequency, V2 represents the potential gradient, ε represents the dielectric constant, and tanδ represents the dielectric tangent. As can be seen from the above formula, the higher the frequency, the greater the dielectric constant and dielectric tangent, and the greater the dielectric loss.

[0004] At present, the 4G communication circuit board substrate on the market uses a glass fiber reinforced epoxy resin board, while the 5G antenna vibrator uses a glass fiber reinforced polyphenylene sulfide composition. However, since polyphenylene sulfide resin itself is a semi-crystalline material with super high fluidity and great processing difficulty, most polyphenylene sulfide needs to be modified with glass fiber to greatly improve its temperature resistance. However, since the difficulty of injection molding is still very high, the molded products are prone to flash, requiring additional manual trimming, resulting in low production efficiency; and the 40% glass fiber reinforced polyphenylene sulfide composition currently supplied on the market has very unstable dielectric properties, and the dielectric constant varies with different batches of raw materials, making it difficult to guarantee product stability. E-glass fiber is currently commonly used in printed circuit boards. At room temperature, at a frequency of 1MHz, the dielectric constant is about 6.5-7.2, and the dielectric tangent is about 12×10 -4, it can be seen that E-glass fiber generally produces relatively high dielectric loss and cannot meet the high-frequency and high-speed printed circuit board requirements of the 5G era; and because different batches of glass fiber are very different, the 40% glass fiber reinforced polyphenylene sulfide composition cannot stably control the dielectric constant within a certain range, resulting in serious defects in the line impedance after the later circuit board assembly. After testing, the dielectric constant of the 40% glass fiber reinforced polyphenylene sulfide composition is greater than 4.2 at high frequencies, and the test values ​​of dielectric loss at high frequencies are greater than 0.006, which is very easy to cause signal delays and does not meet the needs of future high-frequency development of 5G; at the same time, the 40% glass fiber reinforced polyphenylene sulfide composition has high hygroscopicity, and long-term use in outdoor 5G base stations will cause the circuit to be damp, affecting electrical performance.

[0005] Polyphenylene ether resin is also a circuit board material suitable for high-frequency electronic devices because it has good high-frequency characteristics, such as low dielectric constant and low dielectric loss. However, the disadvantage of polyphenylene ether resin is poor moldability, so it cannot be used alone and can only be used in the form of a mixture with a fully compatible polystyrene-based resin or a plasticizer triphenyl phosphate. Although polystyrene-based resin can increase the fluidity of polyphenylene ether-based resin, its introduction reduces the flame retardancy and heat resistance of polyphenylene ether resin and cannot meet the processing requirements of flexible copper clad laminates; and although the mixture of plasticizer triphenyl phosphate can increase the fluidity and flame retardancy of polyphenylene ether resin, it has a greater loss in temperature resistance. Glass fiber is usually added to enhance heat resistance.

[0006] The low dielectric constant glass fibers currently available on the market are only suitable for PA, PBT and PPS, and there is no low dielectric constant glass fiber suitable for polyphenylene ether. After using the existing low dielectric constant glass fibers for the modification of polyphenylene ether, it was found that its dielectric properties were poor and its moisture absorption rate was very high, which was not conducive to the processing of the downstream PCB industry. For example, in the prior art CN113652074A, a polyphenylene ether substrate for high-frequency and high-speed copper-clad laminates and its preparation method and application were disclosed. The polyphenylene ether substrate includes, by mass percentage: 30-90% polyphenylene ether resin, 10-40% glass fiber, 0.1-50% inorganic filler, 0.01-0.5% antioxidant, 0.01-0.5% light stabilizer, 0.01-0.5% release agent, 0.1-10% processing aid, and 0-20% plasticizer. This solution uses the interaction between the processing aid (nano-siloxane) and polyphenylene ether to make polyphenylene ether form an orderly crystalline structure, thereby increasing fluidity to meet the needs of downstream production processes. However, as can be seen from its conclusion 3, the main improvement of this solution is only in fluidity, and has little effect on the dielectric properties directly related to the performance of the end product; and this solution does not consider the effect of ambient humidity on the dielectric properties of the material, resulting in a large change in the dielectric properties of its products in a high humidity environment due to insufficient bonding between polyphenylene ether and glass fiber, and ultimately unable to meet performance requirements and not in line with actual application environments.

[0007] Therefore, it is necessary to study the composition using polyphenylene ether resin as a high-frequency electronic substrate in order to propose a polyphenylene ether resin composition having a low dielectric constant, low dielectric loss, and being suitable for downstream PCB processing. Summary of the invention

[0008] The purpose of the present invention is to provide a low dielectric constant glass fiber reinforced polyphenylene ether composition and its preparation method and application in order to solve at least one of the above problems, so as to solve the problems of difficult processing, insufficient batch stability and high hygroscopicity of polyphenylene sulfide resin compositions in the prior art. The modified glass fiber and the polyphenylene ether resin of this scheme have good bonding, which can give full play to the performance advantages of polyphenylene ether itself and effectively reduce the water absorption rate of the composition. It is prepared by twin-screw extrusion, with high overall production efficiency and excellent product quality.

[0009] The purpose of the present invention is achieved through the following technical solutions:

[0010] The first aspect of the present invention discloses a low dielectric constant glass fiber reinforced polyphenylene ether composition, comprising the following components by mass:

[0011]

[0012] The low dielectric constant and low loss glass fiber has a dielectric constant of less than 3.8 and a dielectric loss of less than 0.001 under the condition of 1 MHz; the surface of the low dielectric constant and low loss glass fiber is covered with carbon-doped silicon oxide as a coupling agent.

[0013] Preferably, the low dielectric constant and low loss glass fiber comprises the following components by mass: 50-52% silicon dioxide, 13-15% aluminum oxide, 24-26% boron oxide, 3-5% calcium oxide, 3-5% magnesium oxide and 0.1-1.5% zirconium oxide.

[0014] Preferably, the low dielectric constant and low loss glass fiber is prepared by the following steps: mixing the components and melting them once, quenching to obtain cullet, and melting them twice to obtain glass fiber precursor; impregnating the glass fiber precursor in carbon-doped silicon oxide, then transferring it to a preheated oven to remove surface bubbles, then transferring it to a vacuum oven for drying and curing, and finally chopping it by a chopper.

[0015] Preferably, the temperature of the primary melting is 1300-1550°C, and the temperature is kept for 5-10 hours; the temperature of the secondary melting is 1300-1350°C, and the temperature is kept for 0.5-1h; the surface bubbles are removed in an oven at 50-80°C; and the drying and curing is carried out in three steps, namely: drying at 50°C for 1 hour, drying at 100°C for 2 hours, and drying at 120°C for 4 hours.

[0016] Preferably, the weight of the carbon-doped silicon oxide is 0.1-5% of the glass fiber.

[0017] Preferably, the inorganic filler includes one or more of titanium dioxide, aluminum oxide, kaolin and talc; the processing aid includes an antioxidant, a light stabilizer, a release agent, a UV stabilizer and a lubricant.

[0018] Preferably, the polyphenylene ether composition further comprises 0-30% by weight of polystyrene and / or 0-20% by weight of a plasticizer.

[0019] The second aspect of the present invention discloses a method for preparing any of the above-mentioned low dielectric constant glass fiber reinforced polyphenylene ether compositions, comprising the following steps:

[0020] Firstly, polyphenylene ether and a processing aid are premixed, and then an inorganic filler is added and mixed to obtain a premix;

[0021] The premix is ​​added from the main feeder of the twin-screw extruder, and the low dielectric constant and low loss glass fiber is added from the side feeder of the twin-screw extruder for extrusion granulation.

[0022] Preferably, the polyphenylene ether and the processing aid are premixed at 500-700 rpm for 8-10 min, and after the inorganic filler is added, they are mixed at 200-300 rpm for 30-45 s; the feeding zone temperature of the twin-screw extruder is 50-100°C, the melting zone temperature is 280-300°C, the mixing zone temperature is 280-310°C, the dispersion zone temperature is 280-320°C, the rotation speed is 280-350 rpm, and the total extrusion speed is 25-50 kg / h.

[0023] The third aspect of the present invention discloses the use of any of the above-mentioned low dielectric constant glass fiber reinforced polyphenylene ether compositions in high-frequency electronic devices.

[0024] The working principle of the present invention is:

[0025] Carbon-doped silicon oxide molecules easily form three open-ring silicon-oxygen bonds at high temperatures, and can then easily combine with the terminal hydroxyl groups of polyphenylene ether molecules in a twin-screw extruder to form grafts, thereby improving the bonding between glass fiber and polyphenylene ether, thereby enhancing the polymer's temperature resistance, impact resistance and rigidity, and reducing the water absorption of its molded products. According to existing research (Wang Jun, Wang Jianghua. Study on the influence of water absorption on dielectric constant and dielectric loss angle [J]. Printed Circuit Information, 2010 (11): 4. DOI: 10.3969 / j.issn.1009-0096.2010.11.005.), it can be seen that the water absorption of the material is proportional to the influence of the dielectric constant and dielectric loss. Therefore, the smaller the water absorption of the material, the smaller the dielectric constant and dielectric loss of the copper clad laminate made from it.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The present invention discloses a low dielectric constant glass fiber reinforced polyphenylene ether composition and a preparation method thereof, wherein the copper clad laminate prepared therefrom has the characteristics of low dielectric constant, extremely small high frequency dielectric loss performance, excellent temperature resistance and good processing performance. The circuit board made of the substrate material prepared by the present invention can be widely used in 5G base station antenna vibrators, vehicle information and communication systems, electronic non-stop toll collection systems, radar covers (including aircraft, ships, ground and vehicle-mounted radars), military antennas, etc.

[0028] 1. The biggest advantage of polyphenylene ether resin is that it can provide low dielectric constant, low dielectric loss, and conform to the processing characteristics of copper clad laminate materials. The circuit board made of it is not only suitable for the needs of existing high-frequency and high-speed circuit boards, but also because of its low density, high flame retardant performance, and environmentally friendly process routes, it brings possibilities for the development of more 5G products in the future.

[0029] 2. The low dielectric constant and low loss glass fiber reinforced polyphenylene ether resin composition and its preparation method disclosed in the present invention can improve the rigidity and temperature resistance of the polyphenylene ether resin so that it can pass the standard test in the downstream PCB manufacturing process.

[0030] 3. The selected inorganic phosphorus compounds (plasticizer triphenyl phosphate) can improve the flame retardancy, and inorganic fillers such as titanium dioxide, alumina, kaolin and talc can reduce the expansion coefficient and improve heat resistance.

[0031] 4. Carbon-doped silicon oxide (SiCO) is selected as a coupling agent, so that the prepared glass fiber with low dielectric constant and low loss can be grafted with the terminal hydroxyl group of the polyphenylene ether molecule, thereby improving the bonding degree of the glass fiber and greatly reducing the water absorption rate of its molded product.

[0032] 5. Use a twin-screw extruder to mix the formula evenly and then form and granulate it. The product has good moldability and is easy to process. It will not cause injection molding problems such as flash and has high production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a structural schematic diagram of the preparation process of a twin-screw extruder.

[0034] Figure 2 This is a schematic diagram of the structure of the glass fiber drawing test line. DETAILED DESCRIPTION

[0035] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] In the following description, unless otherwise specified, the reagents used are conventional commercially available products, and the methods used are well known in the art.

[0037] A low dielectric constant and low loss glass fiber reinforced polyphenylene ether composition. The composition comprises:

[0038]

[0039] The low dielectric constant and low loss glass fiber has a dielectric constant of less than 3.8, a dielectric loss of less than 0.001, a glass density of 2.28-2.32, and a thermal expansion coefficient of less than 3.5 when tested under 1MHz conditions. The borosilicate glass fiber contains 50-52% by mass of silicon dioxide, 13-15% by mass of aluminum oxide, 24-26% by mass of boron oxide, 3-5% by mass of calcium oxide, 3-5% by mass of magnesium oxide, and 0.1-1.5% by mass of zirconium oxide.

[0040] Weigh the components of the glass fiber in proportion, mix them evenly, and place them in a crucible. Melt them in an electric furnace at a high temperature of 1300-1550°C. Keep them warm for 5-10 hours, and quench them to obtain broken glass. Use a glass fiber drawing test line, and its core action part structure is as follows Figure 2 As shown, secondary melting for 0.5-1 hour under the condition of 1300-1350°C obtains low dielectric constant and low loss glass fiber precursor, whose fiber diameter is 4-15 microns. The glass fiber precursor is impregnated in a container, and carbon-doped silicon oxide (SiCO) produced by Hybrid Plastics Company of the United States is added as a coupling agent, and the mass ratio accounts for 0.1-5% of the coupling agent ratio. The impregnated glass fiber precursor is placed in a 50-80°C oven for preheating to remove surface bubbles. Then put it in a vacuum oven and set three stages of drying temperature, that is, drying at 50°C for 1 hour, drying at 100°C for 2 hours, and drying at 120°C for 4 hours to fully solidify it. The low dielectric constant and low loss glass fiber precursor obtained in this way has few surface defects and no bubbles. Then the glass fiber is prepared into chopped yarn through a short cutter, and the length is about 1-13mm.

[0041] Carbon-doped silicon oxide molecules tend to form three open-ring silicon-oxygen bonds at high temperatures, and combine with the hydroxyl end groups of polyphenylene ether molecules in a twin-screw extruder to form grafts, thereby increasing the bonding degree of glass fibers, enhancing the polymer's temperature resistance, impact resistance and rigidity, and reducing the water absorption of its molded products. Molded products include injection molded products, heated extruded sheets, films, wire drawing products, die-cast products, and hot-pressed sheets. Studies have shown that "Study on the Influence of Water Absorption on Dielectric Constant and Dielectric Loss Angle", Suzhou Shengyi Technology Co., Ltd., the water absorption of materials is proportional to the influence of dielectric constant and dielectric loss. The smaller the water absorption of the material, the smaller the dielectric constant and dielectric loss of the copper clad laminate made from it.

[0042] The inorganic filler includes one or more of titanium dioxide, aluminum oxide, kaolin, and talc.

[0043] Processing aids include antioxidants, light stabilizers, release agents, UV stabilizers, lubricants, etc., which are added in appropriate amounts as needed to improve or increase corresponding performance without affecting other properties of the composite resin.

[0044] The preparation method of the resin composition is to use a twin-screw extruder production line to premix the polyphenylene ether resin and the processing aid, set the blade speed to 500-700 rpm in the high-speed mixer, add inorganic fillers such as titanium dioxide, barium titanate, etc. after mixing for 8-10 minutes, set the slurry speed to 200-300 rpm, mix for 30-45 seconds, and obtain a premix. Place this premix in the main feeder, and place the low dielectric constant and low loss glass fiber in the side feeder. Set the feeding zone temperature of the twin-screw extruder to 50-100°C, the melting zone temperature to 280-300°C, the mixing zone temperature to 280-310°C, and the dispersion zone temperature to 280-320°C. Set the twin-screw extruder speed to 280-350RPM, and the total extrusion speed to 25-50kg / h. According to the following process ( Figure 1 ) is modified and granulated to obtain the product.

[0045] In the following examples, polyphenylene ether uses Bluestar's LXR series, glass fiber is purchased from Chongqing International Composite Materials CPIC, inorganic fillers are purchased from Chemours Chemical, processing aids are all products of Hybrid Plastics in the United States (the selected processing aids only need to meet the functional requirements, and there is no special restriction on the specific model), polystyrene is selected from Zhenjiang Chimei Chemical, and the plasticizer (triphenyl phosphate) comes from Zhejiang Wansheng.

[0046] Comparative Example 1

[0047] Weigh the components of the glass fiber according to the following proportions: 50% silica, 15% alumina, 25% boron oxide, 5% calcium oxide, 4% magnesium oxide, and 1% zirconium oxide. Mix well and place in a crucible, melt at high temperature in an electric furnace at 1350°C, keep warm for 8 hours, and obtain broken glass after quenching; use a glass fiber drawing test line, melt twice at 1350°C for 0.5 hours to obtain a low dielectric constant and low loss glass fiber precursor with a fiber diameter of about 13 microns. Impregnate the glass fiber precursor in a container and the impregnating agent for 30 minutes, preheat the impregnated glass fiber precursor in a 50°C oven to remove surface bubbles. Then put it in a vacuum oven and set three stages of drying temperature, i.e., drying at 50°C for 1 hour, drying at 100°C for 2 hours, and drying at 120°C for 4 hours to completely solidify it. The low dielectric constant and low loss glass fiber raw yarn obtained in this way has few surface defects and no bubbles. The glass fiber is then passed through a short cut machine to prepare short cut yarn A (surface unmodified) with a length of about 4 mm.

[0048] The chopped yarn A is used to modify the polyphenylene ether composition. The composition 1 is weighed according to the following ratio and plastic particles are obtained through a twin-screw extrusion production line.

[0049]

[0050] The specific preparation method is:

[0051] 1) Premixing polyphenylene ether resin and polystyrene, processing aid antioxidant and processing aid light stabilizer, in a high-speed mixer, controlling the blade speed to 500 rpm, mixing for 8 minutes, then adding inorganic filler talcum powder, controlling the slurry speed to 200 rpm, mixing for 30 seconds, to obtain a premix.

[0052] 2) Place the premix in the main feeder of the twin-screw extruder production line, and place the chopped yarn A in the side feeder of the twin-screw extruder production line. Control the temperature of the twin-screw extruder feeding zone at 50°C, the temperature of the melting zone at 280°C, the temperature of the mixing zone at 280°C, the temperature of the dispersion zone at 280°C, and the speed of the twin-screw extruder at 280RPM, with a total extrusion speed of 25kg / h. According to the following process ( Figure 1 ) is modified and granulated to obtain composition 1.

[0053] Comparative Example 2

[0054] Weigh the components of the glass fiber according to the following proportions: 50% silica, 15% alumina, 25% boron oxide, 5% calcium oxide, 4% magnesium oxide, and 1% zirconium oxide. Mix well and place in a crucible, melt at high temperature in an electric furnace at 1350°C, keep warm for 8 hours, and obtain broken glass after quenching; use a glass fiber drawing test line, melt twice at 1350°C for 0.5 hours to obtain a low dielectric constant and low loss glass fiber precursor with a fiber diameter of about 13 microns. Impregnate the glass fiber precursor in a container and the impregnating agent for 30 minutes, preheat the impregnated glass fiber precursor in a 50°C oven to remove surface bubbles. Then put it in a vacuum oven and set three stages of drying temperature, i.e., drying at 50°C for 1 hour, drying at 100°C for 2 hours, and drying at 120°C for 4 hours to completely solidify it. The low dielectric constant and low loss glass fiber raw yarn obtained in this way has few surface defects and no bubbles. The glass fiber is then passed through a short cut machine to prepare short cut yarn A (surface unmodified) with a length of about 4 mm.

[0055] The chopped yarn A is used to modify the polyphenylene ether composition, and the composition 2 is weighed according to the following ratio, and plastic particles are obtained through a twin-screw extrusion production line.

[0056]

[0057] The specific preparation method is:

[0058] 1) Premixing polyphenylene ether resin, plasticizer, processing aid antioxidant and processing aid light stabilizer, in a high-speed mixer, controlling the blade speed to 500 rpm, mixing for 8 minutes, then adding inorganic filler talcum powder, controlling the slurry speed to 200 rpm, mixing for 30 seconds, to obtain a premix.

[0059] 2) Place the premix in the main feeder of the twin-screw extruder production line, and place the chopped yarn A in the side feeder of the twin-screw extruder production line. Control the temperature of the twin-screw extruder feeding zone at 50°C, the temperature of the melting zone at 280°C, the temperature of the mixing zone at 280°C, the temperature of the dispersion zone at 280°C, and the speed of the twin-screw extruder at 280RPM, with a total extrusion speed of 25kg / h. According to the following process ( Figure 1 ) is modified and granulated to obtain composition 2.

[0060] Example 1

[0061] Weigh the components of the glass fiber according to the following proportions: 50% by mass of silicon dioxide, 15% by mass of aluminum oxide, 25% by mass of boron oxide, 5% by mass of calcium oxide, 4% by mass of magnesium oxide, and 1% by mass of zirconium oxide. Mix them evenly and place them in a crucible, and melt them in an electric furnace at a high temperature of 1350°C for 8 hours. After quenching, obtain broken glass; use a glass fiber drawing test line and melt it again at 1350°C for 0.5 hours to obtain a low dielectric constant and low loss glass fiber precursor with a fiber diameter of about 13 microns. Immerse the glass fiber precursor in a container and an impregnating agent for 30 minutes, and add carbon-doped silicon oxide (SiCO) produced by Hybrid Plastics Company of the United States as a coupling agent, with a mass ratio of 3% of the coupling agent ratio. Preheat the impregnated glass fiber precursor in a 50°C oven to remove surface bubbles. Then put it into a vacuum oven and set three stages of drying temperature, i.e. drying at 50°C for 1 hour, drying at 100°C for 2 hours, and drying at 120°C for 4 hours, to make it completely solidified. The low dielectric constant and low loss glass fiber raw yarn obtained in this way has few surface defects and no bubbles. Then the glass fiber is prepared into chopped yarn B (surface modified) through a short cutter, and the length is about 4 mm.

[0062] The chopped yarn B was used to modify the polyphenylene ether composition, and the composition 3 was weighed according to the following ratio, and plastic particles were obtained through a twin-screw extrusion production line.

[0063]

[0064] The specific preparation method is:

[0065] 1) Premixing polyphenylene ether resin, plasticizer, processing aid antioxidant and processing aid light stabilizer, in a high-speed mixer, controlling the blade speed to 500 rpm, mixing for 8 minutes, then adding inorganic filler talcum powder, controlling the slurry speed to 200 rpm, mixing for 30 seconds, to obtain a premix.

[0066] 2) Place the premix in the main feeder of the twin-screw extruder production line, and place the chopped yarn B in the side feeder of the twin-screw extruder production line. Control the temperature of the twin-screw extruder feeding zone at 50°C, the temperature of the melting zone at 280°C, the temperature of the mixing zone at 280°C, the temperature of the dispersion zone at 280°C, and the speed of the twin-screw extruder at 280RPM, with a total extrusion speed of 25kg / h. According to the following process ( Figure 1 ) was modified and granulated to obtain composition 3.

[0067] Example 2

[0068] Weigh the components of the glass fiber according to the following proportions: 50% by mass of silicon dioxide, 15% by mass of aluminum oxide, 25% by mass of boron oxide, 5% by mass of calcium oxide, 4% by mass of magnesium oxide, and 1% by mass of zirconium oxide. Mix them evenly and place them in a crucible, and melt them in an electric furnace at a high temperature of 1350°C for 8 hours. After quenching, obtain broken glass; use a glass fiber drawing test line and melt them again at 1350°C for 0.5 hours to obtain a low dielectric constant and low loss glass fiber precursor with a fiber diameter of about 13 microns. Immerse the glass fiber precursor in a container and an impregnating agent for 30 minutes, and add carbon-doped silicon oxide (SiCO) produced by Hybrid Plastics Company of the United States as a coupling agent, with a mass ratio of 3% of the coupling agent ratio. Preheat the impregnated glass fiber precursor in a 50°C oven to remove surface bubbles. Then put it into a vacuum oven and set three stages of drying temperature, i.e. drying at 50°C for 1 hour, drying at 100°C for 2 hours, and drying at 120°C for 4 hours, to make it completely solidified. The low dielectric constant and low loss glass fiber raw yarn obtained in this way has few surface defects and no bubbles. Then the glass fiber is prepared into chopped yarn B (surface modified) through a short cutter, and the length is about 4 mm.

[0069] The chopped yarn B was used to modify the polyphenylene ether composition, and the composition 4 was weighed according to the following ratio, and plastic particles were obtained through a twin-screw extrusion production line.

[0070]

[0071] The specific preparation method is:

[0072] 1) Premixing polyphenylene ether resin and polystyrene, processing aid antioxidant and processing aid light stabilizer, in a high-speed mixer, controlling the blade speed to 500 rpm, mixing for 8 minutes, then adding inorganic filler titanium dioxide, controlling the slurry speed to 200 rpm, mixing for 30 seconds, to obtain a premix.

[0073] 2) Place the premix in the main feeder of the twin-screw extruder production line, and place the chopped yarn B in the side feeder of the twin-screw extruder production line. Control the temperature of the twin-screw extruder feeding zone at 50°C, the temperature of the melting zone at 280°C, the temperature of the mixing zone at 280°C, the temperature of the dispersion zone at 280°C, and the speed of the twin-screw extruder at 280RPM, with a total extrusion speed of 25kg / h. According to the following process ( Figure 1 ) was modified and granulated to obtain composition 4.

[0074] Comparative Example 3

[0075] The low dielectric constant glass fiber ECS309-3-K / HL of Chongqing Composite International Co., Ltd. CPIC was purchased, and the fiber diameter was 13 microns, which was recorded as chopped yarn C. The chopped yarn C was used to modify the polyphenylene ether composition, and the composition 5 was weighed according to the following ratio, and plastic particles were obtained through a twin-screw extrusion production line.

[0076]

[0077] The specific preparation method is:

[0078] 1) Premixing polyphenylene ether resin and polystyrene, processing aid antioxidant and processing aid light stabilizer, in a high-speed mixer, controlling the blade speed to 500 rpm, mixing for 8 minutes, then adding inorganic filler titanium dioxide, controlling the slurry speed to 200 rpm, mixing for 30 seconds, to obtain a premix.

[0079] 2) Place the premix in the main feeder of the twin-screw extruder production line, and place the chopped yarn B in the side feeder of the twin-screw extruder production line. Control the temperature of the twin-screw extruder feeding zone at 50°C, the temperature of the melting zone at 280°C, the temperature of the mixing zone at 280°C, the temperature of the dispersion zone at 280°C, and the speed of the twin-screw extruder at 280RPM, with a total extrusion speed of 25kg / h. According to the following process ( Figure 1 ) was modified and granulated to obtain composition 5.

[0080] Comparative Example 4

[0081] The low dielectric constant glass fiber ECS301HP-3-K / HL of Chongqing Composite International Co., Ltd. CPIC was purchased, and the fiber diameter was 13 microns, which was recorded as chopped yarn D. The chopped yarn D was used to modify the polyphenylene ether composition, and the composition 6 was weighed according to the following ratio, and plastic particles were obtained through a twin-screw extrusion production line.

[0082]

[0083]

[0084] The specific preparation method is:

[0085] 1) Premixing polyphenylene ether resin, plasticizer, processing aid antioxidant and processing aid light stabilizer, in a high-speed mixer, controlling the blade speed to 500 rpm, mixing for 8 minutes, then adding inorganic filler titanium dioxide, controlling the slurry speed to 200 rpm, mixing for 30 seconds, to obtain a premix.

[0086] 2) Place the premix in the main feeder of the twin-screw extruder production line, and place the chopped yarn B in the side feeder of the twin-screw extruder production line. Control the temperature of the twin-screw extruder feeding zone at 50°C, the temperature of the melting zone at 280°C, the temperature of the mixing zone at 280°C, the temperature of the dispersion zone at 280°C, and the speed of the twin-screw extruder at 280RPM, with a total extrusion speed of 25kg / h. According to the following process ( Figure 1 ) was modified and granulated to obtain composition 5.

[0087] Comparative Example 5

[0088] This comparative example is a PPS composition, and the PPS composition is purchased from Celanese 1140L4.

[0089] The dielectric constant and dielectric loss of the composite plastic particles of the above embodiments and comparative examples were tested at different frequencies using the quasi-optical cavity method, the heat deformation temperature was tested using the ISO 75-2 / A method, and the water absorption was tested under different conditions using a constant temperature and humidity chamber. The test results are shown in Tables 1-3.

[0090] Table 1 Dielectric constant (DK) and dielectric loss (Df) of the resin compositions of Examples 1, 2 and Comparative Examples 1-5 at different frequencies

[0091]

[0092] Conclusion 1 can be drawn from Table 1: The dielectric loss of the polyphenylene ether resin composition is better than that of the polyphenylene sulfide resin composition. The dielectric constants of composition 4 and composition 5 are higher than those of composition 1, composition 2, composition 3 and composition 6. This is because their systems contain titanium dioxide, and the dielectric constant of apatite titanium dioxide is 48.

[0093] Table 2 Heat deformation temperature (°C) of the resin compositions of Examples 1, 2 and Comparative Examples 1-5

[0094]

[0095] Conclusion 2 can be drawn from Table 2: The heat deformation temperatures of polyphenylene ether compositions 1, 4 and 5 containing polystyrene groups are all lower than 170° C., which cannot meet the requirements of downstream PCB processing.

[0096] Table 3 Dielectric constants and dielectric losses of the resin compositions of Examples 1, 2 and Comparative Examples 1-5 at 20 GHz and different humidity

[0097]

[0098] Conclusion 3 is drawn from Table 3: The dielectric constant of the PPS composition drifts with the increase of relative humidity, which cannot meet the PCB industry requirement of dielectric constant drift within the range of ±0.1, and its dielectric loss also increases with the increase of relative humidity. Composition 3 shows the best performance, and the dielectric constant and dielectric loss remain almost unchanged with the change of relative humidity. Composition 1, Composition 2 and Composition 4 show acceptable performance. Composition 5 and Composition 6 are not suitable for the modification of polyphenylene ether because glass fiber is not suitable for the modification of polyphenylene ether, the bonding force between polyphenylene ether resin and glass fiber is very poor, and the surface of the test sample is uneven, which easily absorbs water molecules, so that its dielectric loss increases significantly with the increase of relative humidity.

[0099] According to the performance tests of Tables 1-3, the formulas of composition 3 (Example 1) and composition 4 (Example 2) have the best effect. They can have stable and excellent dielectric constant and dielectric loss at different frequencies or at different relative humidities, and their thermal deformation temperature can fully meet the downstream PCB processing requirements. In the formulas of composition 2 (Comparative Example 2) and composition 3 (Example 1), except for glass fiber, the rest are made of the same proportion and raw materials. By comparing the performance of the two groups, it can be seen that the modified glass fiber proposed in this scheme can still maintain excellent dielectric constant and dielectric loss under high humidity and high frequency, which fully demonstrates that the bonding degree between the modified glass fiber and polyphenylene ether is improved, so its water absorption is low, and the influence on dielectric constant and dielectric loss is small.

[0100] The above description of the embodiments is to facilitate the understanding and use of the invention by those skilled in the art. It is obvious that those skilled in the art can easily make various modifications to these embodiments and apply the general principles described herein to other embodiments without creative work. Therefore, the present invention is not limited to the above embodiments, and improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the present invention should be within the scope of protection of the present invention.

Claims

1. A low dielectric constant glass fiber reinforced polyphenylene ether composition, characterized in that: The composition includes the following mass contents: Polyphenylene oxide 25-60%; Low dielectric constant and low loss glass fiber 10-40%; Inorganic filler 0.1-50%; Processing aids 0.1-10%; The low dielectric constant and low loss glass fiber has a dielectric constant of less than 3.8 and a dielectric loss of less than 0.001 under the condition of 1 MHz; the surface of the low dielectric constant and low loss glass fiber is covered with carbon-doped silicon oxide as a coupling agent.

2. A low dielectric constant glass fiber reinforced polyphenylene ether composition according to claim 1, characterized in that: The low dielectric constant and low loss glass fiber comprises the following components by mass: 50-52% silicon dioxide, 13-15% aluminum oxide, 24-26% boron oxide, 3-5% calcium oxide, 3-5% magnesium oxide and 0.1-1.5% zirconium oxide.

3. A low dielectric constant glass fiber reinforced polyphenylene ether composition according to claim 2, characterized in that: The low dielectric constant and low loss glass fiber is prepared by the following steps: the components are mixed and melted once, quenched to obtain cullet, and melted twice to obtain glass fiber precursor; the glass fiber precursor is impregnated in carbon-doped silicon oxide, then transferred to a preheated oven to remove surface bubbles, then transferred to a vacuum oven for drying and curing, and finally chopped by a short cutter.

4. A low dielectric constant glass fiber reinforced polyphenylene ether composition according to claim 3, characterized in that: The temperature of the primary melting is 1300-1550°C, and the temperature is kept for 5-10 hours; the temperature of the secondary melting is 1300-1350°C, and the temperature is kept for 0.5-1 hour; the surface bubbles are removed in an oven at 50-80°C; the drying and curing is carried out in three steps, which are: drying at 50°C for 1 hour, drying at 100°C for 2 hours, and drying at 120°C for 4 hours.

5. The low dielectric constant glass fiber reinforced polyphenylene ether composition according to claim 1, characterized in that: The weight of the carbon-doped silicon oxide is 0.1-5% of the glass fiber.

6. The low dielectric constant glass fiber reinforced polyphenylene ether composition according to claim 1, characterized in that: The inorganic filler includes one or more of titanium dioxide, aluminum oxide, kaolin and talcum powder; the processing aid includes antioxidant, light stabilizer, mold release agent, UV stabilizer and lubricant.

7. The low dielectric constant glass fiber reinforced polyphenylene ether composition according to claim 1, characterized in that: The polyphenylene ether composition further comprises polystyrene in an amount of 0-30% by weight, and / or a plasticizer in an amount of 0-20% by weight.

8. A method for preparing a low dielectric constant glass fiber reinforced polyphenylene ether composition as claimed in any one of claims 1 to 7, characterized in that: The steps include: Firstly, polyphenylene ether and a processing aid are premixed, and then an inorganic filler is added and mixed to obtain a premix; The premix is ​​added from the main feeder of the twin-screw extruder, and the low dielectric constant and low loss glass fiber is added from the side feeder of the twin-screw extruder for extrusion granulation.

9. The method for preparing a low dielectric constant glass fiber reinforced polyphenylene ether composition according to claim 8, characterized in that: The polyphenylene ether and the processing aid are premixed at 500-700 rpm for 8-10 minutes, and after the inorganic filler is added, the mixture is mixed at 200-300 rpm for 30-45 seconds; the feeding zone temperature of the twin-screw extruder is 50-100°C, the melting zone temperature is 280-300°C, the mixing zone temperature is 280-310°C, the dispersion zone temperature is 280-320°C, the rotation speed is 280-350 rpm, and the total extrusion speed is 25-50 kg / h.

10. Use of the low dielectric constant glass fiber reinforced polyphenylene ether composition according to any one of claims 1 to 7 in high-frequency electronic equipment.

Images