An epoxy resin composition with low dielectric loss and its preparation method

Abstract

This invention provides an epoxy resin composition with low dielectric loss and its preparation method, belonging to the field of encapsulation materials technology. This invention uses low-dielectric-loss SiO2 micropowder as a filler, which has a lower dielectric constant compared to other types of fillers, thereby reducing dielectric loss. Simultaneously, it introduces a low-dielectric-loss resin and reduces the number of polar groups by increasing the degree of crosslinking, thus achieving the goal of low dielectric loss. While meeting other application requirements, it also reduces dielectric loss to 0.002 ohms or below at mid-to-high frequencies, effectively reducing the ineffective power consumption of devices and increasing the integrity of signal transmission.

Description

Technical Field

[0001] This invention relates to the field of encapsulation materials technology, and in particular to an epoxy resin composition with low dielectric loss and its preparation method. Background Technology

[0002] Dielectric loss refers to the phenomenon where some electrical energy is converted into heat and dissipated in a dielectric material under an alternating electric field (AC field). It is mainly caused by dipole polarization loss, interfacial polarization loss, ionic conductivity loss, and electronic polarization loss. Therefore, the key to reducing dielectric loss is to reduce the accumulation of polar groups. In power devices, high dielectric loss means more electrical energy will be converted into heat, leading to increased wasted energy consumption, and excessively high temperatures will also significantly reduce the device's lifespan. For signal transmission devices, high dielectric loss leads to signal attenuation and distortion. For example, in millimeter-wave radar used in automobiles, high dielectric loss reduces the signal-to-noise ratio (SNR) of the echo signal, resulting in reduced detection accuracy and an increased risk of misjudgment in autonomous driving. Therefore, reducing dielectric loss can effectively reduce energy loss and heat generation, greatly extending the chip's lifespan. Furthermore, reducing dielectric loss can also reduce signal delay and distortion, ensuring stable signal transmission. Epoxy molding compound (EMC) is currently the most widely used semiconductor packaging material, and reducing its dielectric loss is of great significance. Currently, methods for reducing dielectric loss in epoxy molding compounds include: 1. Selecting low-polarity resins and curing agents; 2. Using high-purity, low-Dk fillers; 3. Reducing water absorption and impurities through process optimization. However, due to inherent limitations in resin systems, replacing resins with low-polarity ones can lead to reduced mechanical strength and adhesion, while using high-purity fillers and improving processes can significantly increase costs, resulting in the overall performance of the dielectric material failing to meet market requirements. Therefore, reducing the dielectric loss of epoxy molding compounds has become a pressing technical problem to be solved in this field. Summary of the Invention

[0003] The purpose of this invention is to provide an epoxy resin composition with low dielectric loss and its preparation method. The epoxy resin composition provided by this invention can reduce the dielectric loss to 0.002 or below at medium and high frequencies while meeting other application requirements, effectively reducing the ineffective power consumption of the device and increasing the integrity of signal transmission.

[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0005] This invention provides an epoxy resin composition with low dielectric loss, comprising the following components by mass percentage: 85-95% filler, 1-10% epoxy resin, 1-10% phenolic resin, ≤5% low dielectric loss resin, 0.1-0.8% curing accelerator, 0.1-1% release agent, 0.1-0.8% coupling agent, and 0.2-1% additives;

[0006] The low dielectric loss resin includes any one or more of benzocyclobutene resin, modified polyurethane resin, polyphenylene ether, modified epoxy resin composition, polysiloxane hybrid resin, polyimide resin, maleimide resin, benzoxazine and fluorinated epoxy resin.

[0007] Preferably, the filler is SiO2 micro powder or low dielectric loss SiO2 micro powder;

[0008] The standards for the low dielectric loss SiO2 micro powder are as follows:

[0009]

[0010] Preferably, the epoxy resin includes any one or more of BP epoxy resin, MAR epoxy resin, EOCN epoxy resin, DCPD epoxy resin and MFN epoxy resin.

[0011] Preferably, the phenolic resin includes any one or more of MAR phenolic resin, XYLOK phenolic resin, PN phenolic resin, and MFN phenolic resin.

[0012] Preferably, the curing accelerator comprises any one or more of 4,5-di(hydroxymethyl)-2-phenyl-1H-imidazolium, 4-hydroxymethyl-5-methyl-2-phenylimidazolium, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-S-triazine, N,N-dimethylbenzylamine, phenyl dimethylamine, triphenylphosphine, and triphenylphosphine-1,4-benzoquinone adducts.

[0013] Preferably, the release agent comprises any one or more of polyethylene wax, oxidized polyethylene wax, montmorillonite E wax, Fischer-Tropsch synthetic wax, plant wax, fatty acid glyceride wax, and maleic anhydride grafted modified wax.

[0014] Preferably, the coupling agent is a silane coupling agent; the silane coupling agent includes any one or more of 3-(2,3-epoxypropoxy)propyltrimethoxysilane, 3-(phenylamino)propyltrimethoxysilane and mercaptopropyltrimethoxysilane.

[0015] Preferably, the additive includes any one or more of methyltrimethoxysilane, epoxysilane epoxy resin, and epoxidized 1,3-butadiene.

[0016] Preferably, the epoxy resin composition with low dielectric loss further includes ≤1% colorant by mass percentage; the colorant includes any one or more of iron oxide yellow, carbon black, black spheres, titanium dioxide, ZnO and zinc barium white.

[0017] This invention provides a method for preparing the epoxy resin composition with low dielectric loss described in the above technical solution, comprising the following steps:

[0018] (1) Mix the filler, epoxy resin, phenolic resin, low dielectric loss resin, curing accelerator, release agent, coupling agent and additives evenly to obtain a premix;

[0019] (2) The premixed mixture obtained in step (1) is compounded and extruded, and then cooled and pulverized to obtain an epoxy resin composition with low dielectric loss.

[0020] This invention provides an epoxy resin composition with low dielectric loss, comprising, by weight percentage: 85-95% filler, 1-10% epoxy resin, 1-10% phenolic resin, ≤5% low dielectric loss resin, 0.1-0.8% curing accelerator, 0.1-1% release agent, 0.1-0.8% coupling agent, and 0.2-1% additives; the low dielectric loss resin includes any one or more of benzocyclobutene resin, modified polyurethane resin, polyphenylene ether, modified epoxy resin composition, polysiloxane hybrid resin, polyimide resin, maleimide resin, benzoxazine, and fluorinated epoxy resin. This invention utilizes low dielectric loss SiO2...

[0021] Micropowder, as a filler, has a lower dielectric constant compared to other types of fillers, thereby reducing dielectric loss. Simultaneously, the introduction of low-dielectric-loss resin and the reduction of polar groups by increasing the degree of crosslinking further achieve the goal of low dielectric loss. While meeting other application requirements, it also reduces dielectric loss to 0.002 or below at mid-to-high frequencies, effectively reducing ineffective power consumption and increasing signal transmission integrity. The results of the embodiments show that the epoxy resin composition provided by this invention has a long gelation time and helical flow constant, indicating good processability; the dielectric loss can reach below 0.002 (2.5 GHz), and it has a relatively low water absorption rate, a high glass transition temperature, and a low coefficient of thermal expansion. Attached Figure Description

[0022] Figure 1 Here is a photograph of the epoxy resin composition prepared in Example 3;

[0023] Figure 2 This is a photograph of the epoxy resin composition prepared in Example 8. Detailed Implementation

[0024] This invention provides an epoxy resin composition with low dielectric loss, comprising the following components by mass percentage: 85-95% filler, 1-10% epoxy resin, 1-10% phenolic resin, ≤5% low dielectric loss resin, 0.1-0.8% curing accelerator, 0.1-1% release agent, 0.1-0.8% coupling agent, and 0.2-1% additives;

[0025] The low dielectric loss resin includes any one or more of benzocyclobutene resin, modified polyurethane resin, polyphenylene ether, modified epoxy resin composition, polysiloxane hybrid resin, polyimide resin, maleimide resin, benzoxazine and fluorinated epoxy resin.

[0026] Unless otherwise specified, all raw materials used in this invention are commercially available products well known to those skilled in the art.

[0027] The epoxy resin composition with low dielectric loss provided by the present invention comprises 85-95% filler by weight percentage; the filler is preferably SiO2 micro powder or low dielectric loss SiO2 micro powder; the particle size of the SiO2 micro powder or low dielectric loss SiO2 micro powder is preferably 0.1-75 μm.

[0028] In this invention, the preferred standard for the low dielectric loss SiO2 micro powder is as follows:

[0029]

[0030] In one embodiment of the present invention, the mass percentage of the filler can be 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, or 95%. The present invention reduces the dielectric loss of the entire composition by adding SiO2 micropowder or low-dielectric-loss SiO2 micropowder to the epoxy resin composition. The low-dielectric-loss SiO2 micropowder is obtained by surface treatment of conventional SiO2 micropowder and has even lower dielectric loss, further reducing the dielectric loss of the epoxy resin composition.

[0031] The epoxy resin composition with low dielectric loss provided by the present invention comprises 1-10% epoxy resin by weight percentage; the epoxy resin preferably includes any one or more of BP epoxy resin, MAR epoxy resin, EOCN epoxy resin, DCPD epoxy resin, and MFN epoxy resin; the average molecular weight of the epoxy resin is preferably 180-620; the epoxy equivalent of the BP epoxy resin is preferably 180-210; the epoxy equivalent of the MAR epoxy resin is preferably 260-290; the epoxy equivalent of the EOCN epoxy resin is preferably 194-204; the epoxy equivalent of the DCPD epoxy resin is preferably 250-280; and the epoxy equivalent of the MFN epoxy resin is preferably 156-168. As one embodiment of the present invention, the weight percentage of the epoxy resin can be 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, or 10%. As a component of the present invention, the epoxy resin, as a bonding material, enables a strong bond between the components.

[0032] As one embodiment of the present invention, the chemical formulas of the BP epoxy resin, MAR epoxy resin, EOCN epoxy resin, DCPD epoxy resin, and MFN epoxy resin can be as follows:

[0033] .

[0034] The epoxy resin composition with low dielectric loss provided by the present invention comprises 1-10% phenolic resin by weight percentage; the phenolic resin preferably includes any one or more of MAR phenolic resin, XYLOK phenolic resin, PN phenolic resin, and MFN phenolic resin; the average molecular weight of the phenolic resin is preferably 100-400. As one embodiment of the present invention, the weight percentage of the phenolic resin can be 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, or 10%. In the present invention, the phenolic resin acts as a curing agent and undergoes a crosslinking reaction with the epoxy resin under the action of a catalyst.

[0035] As one embodiment of the present invention, the chemical formulas of the MAR phenolic resin, XYLOK phenolic resin, PN phenolic resin, and MFN phenolic resin can be as follows:

[0036] .

[0037] The epoxy resin composition with low dielectric loss provided by this invention, by mass percentage, comprises ≤5% low dielectric loss resin, preferably 1-5%; the low dielectric loss resin includes any one or more of benzocyclobutene resin, modified polyurethane resin, polyphenylene ether, modified epoxy resin composition, polysiloxane hybrid resin, polyimide resin, maleimide resin, benzoxazine, and fluorinated epoxy resin; the average molecular weight of the low dielectric loss resin is preferably 500-6500. In this invention, when the mass percentage of the low dielectric loss resin is 0, the filler is preferably low dielectric loss SiO2 micro powder. As one embodiment of this invention, the mass percentage of the low dielectric loss resin can be 1%, 2%, 3%, 4%, or 5%. By adding a certain amount of low dielectric loss resin, this invention can significantly reduce the dielectric loss of the composition.

[0038] The epoxy resin composition with low dielectric loss provided by the present invention comprises 0.1-0.8% (by weight percentage) a curing accelerator; the curing accelerator preferably comprises any one or more of 4,5-di(hydroxymethyl)-2-phenyl-1H-imidazolium, 4-hydroxymethyl-5-methyl-2-phenylimidazolium, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-S-triazine, N,N-dimethylbenzylamine, phenyldimethylamine, triphenylphosphine, and triphenylphosphine-1,4-benzoquinone adducts. As one embodiment of the present invention, the weight percentage of the curing accelerator may be 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, or 0.8%. By adding a curing accelerator to the epoxy resin composition, the present invention can accelerate the curing speed of the composition, thereby improving its processing performance.

[0039] The epoxy resin composition with low dielectric loss provided by this invention comprises 0.1-1% mold release agent by weight percentage; the mold release agent preferably includes any one or more of polyethylene wax, oxidized polyethylene wax, montmorillonite E wax, Fischer-Tropsch synthetic wax, plant wax, fatty acid glyceride wax, and maleic anhydride grafted modified wax. As one embodiment of this invention, the weight percentage of the mold release agent can be 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, or 1%. By adding a mold release agent to the epoxy resin composition, this invention facilitates easier demolding after curing, avoids damage during demolding, improves yield, and thus enhances its market competitiveness.

[0040] The epoxy resin composition with low dielectric loss provided by the present invention comprises 0.1-0.8% coupling agent by mass percentage; the coupling agent is preferably a silane coupling agent; the silane coupling agent preferably includes any one or more of 3-(2,3-epoxypropoxy)propyltrimethoxysilane, 3-(phenylamino)propyltrimethoxysilane, and mercaptopropyltrimethoxysilane. As one embodiment of the present invention, the mass percentage of the coupling agent can be 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, or 0.8%. The present invention allows for surface treatment of the filler by adding a coupling agent.

[0041] The epoxy resin composition with low dielectric loss provided by the present invention comprises 0.2-1% additives by weight percentage; the additives preferably include any one or more of methyltrimethoxysilane, epoxysilane epoxy resin, and epoxidized cyclized 1,3-butadiene. As one embodiment of the present invention, the weight percentage of the additives can be 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, or 1%. The present invention uses the above-mentioned additives to achieve defoaming and toughening effects.

[0042] The epoxy resin composition with low dielectric loss provided by the present invention preferably further includes ≤1% colorant by mass percentage, more preferably 0.1-1%; the colorant preferably includes any one or more of iron oxide yellow, carbon black, black spheres, titanium dioxide, ZnO, and zinc barium white; the particle size of the carbon black is preferably 10-100 nm, more preferably 10-50 nm; the particle size of the black spheres is preferably 1-20 μm, more preferably 1-10 μm. As one embodiment of the present invention, the mass percentage of the colorant can be 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, or 1%. By adding colorant to the epoxy resin composition, the present invention can produce different colors as needed, thereby improving the market competitiveness of the product.

[0043] This invention uses low-dielectric-loss SiO2 micro powder as a filler, which has a lower dielectric constant than other types of fillers, thereby reducing dielectric loss. At the same time, it introduces low-dielectric-loss resin and reduces the number of polar groups by increasing the degree of crosslinking to achieve the goal of low dielectric loss. While meeting other application requirements, it reduces dielectric loss to 0.002 and below at medium and high frequencies, effectively reducing the ineffective power consumption of the device and increasing the integrity of signal transmission.

[0044] The present invention also provides a method for preparing the epoxy resin composition with low dielectric loss described in the above technical solution, comprising the following steps:

[0045] (1) Mix the filler, epoxy resin, phenolic resin, low dielectric loss resin, curing accelerator, release agent, coupling agent and additives evenly to obtain a premix;

[0046] (2) The premixed mixture obtained in step (1) is compounded and extruded, and then cooled and pulverized to obtain an epoxy resin composition with low dielectric loss.

[0047] The present invention involves uniformly mixing fillers, epoxy resin, phenolic resin, low dielectric loss resin, curing accelerator, release agent, coupling agent and additives to obtain a premix.

[0048] The present invention does not have any special limitations on the specific operation of the uniform mixing, and stirring and mixing well known to those skilled in the art can be used.

[0049] In this invention, when the epoxy resin composition with low dielectric loss includes a colorant, the colorant is preferably mixed uniformly with filler, epoxy resin, phenolic resin, low dielectric loss resin, curing accelerator, release agent, coupling agent and additives to obtain a premix.

[0050] After obtaining the premix, the present invention performs compounding and extrusion of the premix, followed by cooling and pulverizing to obtain an epoxy resin composition with low dielectric loss.

[0051] In this invention, the preferred temperatures for the compounding extrusion are: 40°C in the first zone, 60°C in the second zone, 140°C in the third zone, 100°C in the fourth zone, and 70°C in the fifth zone; the preferred main engine speed during the compounding extrusion is 220 rpm; and the preferred feeding speed during the compounding extrusion is 105 rpm.

[0052] The present invention does not impose any special limitations on the specific operation of the cooling process; natural cooling or other conventional cooling methods can be used to cool the material to room temperature.

[0053] The present invention does not have any special limitations on the specific operation of the pulverization, as long as the particle size of the epoxy resin composition is suitable for caking.

[0054] In this invention, the epoxy resin composition with low dielectric loss is preferably stored in a low-temperature environment; the temperature of the low-temperature environment is preferably -20~5℃, more preferably -15~-20℃, and even more preferably -18℃.

[0055] The preparation method provided by this invention is simple. It only requires mixing the components evenly, then kneading and extruding to obtain the desired epoxy resin composition with low dielectric loss. No other equipment is needed, which is conducive to large-scale industrial application.

[0056] The technical solutions of this invention will be clearly and completely described below with reference to the embodiments thereof. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0057] Examples 1-8 and Comparative Examples 1-5

[0058] The compositions of the epoxy resin compositions provided in Examples 1-8 and Comparative Examples 1-5 are shown in Tables 1 and 2.

[0059] In Tables 1 and 2, the particle size of both low dielectric loss SiO2 micro powder and SiO2 micro powder is 0.1~75μm.

[0060] The standards for the low dielectric loss SiO2 micro powder are as follows:

[0061]

[0062] The particle size of carbon black is 10~50nm;

[0063] The particle size of the black spheres is 1~10μm;

[0064] The average molecular weight of epoxy resin BP and epoxy resin MAR is 326; the epoxy equivalent of epoxy resin BP is 184; and the epoxy equivalent of MAR epoxy resin is 275.

[0065] The average molecular weights of phenolic resin XYLOK, phenolic resin PN, and phenolic resin MFN are all 200.

[0066] The average molecular weight of the polysiloxane hybrid resin is 1275;

[0067] The preparation method of the epoxy resin composition with low dielectric loss includes the following steps:

[0068] (1) Mix filler, epoxy resin, phenolic resin, low dielectric loss resin, curing accelerator, release agent, coupling agent, colorant and additive evenly to obtain a premix;

[0069] (2) The premixed mixture obtained in step (1) is compounded and extruded, then cooled and pulverized to obtain an epoxy resin composition with low dielectric loss; the compounding and extrusion temperature is: 40°C in the first zone, 60°C in the second zone, 140°C in the third zone, 100°C in the fourth zone, and 70°C in the fifth zone; the main machine speed during compounding and extrusion is 220 rpm, and the feeding speed is 105 rpm;

[0070] Table 1. Composition of the epoxy resin compositions provided in Examples 1-8

[0071]

[0072] Table 2 Composition of the epoxy resin compositions provided in Comparative Examples 1-5

[0073]

[0074] The properties of the epoxy resin compositions provided in Examples 1-8 and Comparative Examples 1-5 were tested, and the results are shown in Tables 3 and 4:

[0075] Table 3 Properties of the epoxy resin compositions provided in Examples 1-8

[0076]

[0077] Table 4. Properties of the epoxy resin compositions provided in Comparative Examples 1-5

[0078]

[0079] In Tables 3 and 4, the test method for gelation time is as follows: The temperature of the hot plate is raised to 175℃, and the temperature setting is adjusted so that the thermometer reading remains at 175℃ ± 1℃. A 1.5g sample is placed on the hot plate and pressed into a 10cm diameter using a flat spatula. 2 For thin slices, when the sample melts and the surface of the melt becomes glossy, start timing with a stopwatch. Use a flat spatula to continuously scrape the sample and observe, or use a needle-shaped stirring rod to continuously stir the sample and observe. The endpoint is when the sample changes from a molten state to a gel state, at which point stop timing and read the required time, which is the gelation time of the sample. Repeat the same operation three times and take the average value. Round the result to the nearest integer.

[0080] The test method for spiral flow length is as follows: When the mold temperature is constant at 175℃, weigh 20g of powdered sample and pour it into the mold cavity for injection molding. Turn on the machine and start timing. After the mold opens automatically, remove the mold and open it. When the thickness of the remaining material in the center block is 4mm, read the length of the longest continuous point. Clean the residual sample from the mold, mold cavity, upper template and injection head. Put the mold back on the press for heat preservation in preparation for the next test. Perform the same operation three times and take the average value. The result is rounded to the nearest integer.

[0081] Dielectric constant and dielectric loss: as specified in GB / T 1409-2006;

[0082] The water absorption rate test method is as follows: Weigh 65±5g of powdered sample and pour it into the mold cavity for injection molding to make a sample block with a thickness of 3mm±0.2mm and a diameter of 50mm±1mm. Place the sample block in a hot air circulating oven at 125℃ and bake for 24h. After the time is up, take the sample block out of the hot air circulating oven and place it in a desiccator to cool to room temperature. Weigh the sample as m1. Then place the sample in a constant temperature and humidity chamber at 85℃ and 85% for 168h to absorb moisture. After the time is up, weigh the sample as m2. According to the formula, the water absorption rate is equal to (m2-m1) / m1.

[0083] Glass transition temperature (T) g The test method is as follows: Weigh 25±5g of powdered sample and pour it into the mold cavity to form a sample block with a diameter of 5mm±0.1mm and a height of 5mm±0.1mm. Install the sample block on the TMA sample stage, ensuring close contact between the probe, the sample, and the sample stage. Apply pressure along the sample axis, starting at 20℃ with a heating rate of 10℃ / min. The recommended termination temperature is 220℃. For materials with high glass transition temperatures, the termination temperature should be set above 300℃. After scanning, obtain the TMA test curve. Plot tangents at both the temperatures above and below the transition temperature. The temperature at the intersection of the two tangents is the glass transition temperature T. g ;

[0084] The test method for linear thermal expansion coefficients (α1 and α2) is as follows: Weigh 25±5g of powdered sample and pour it into the mold cavity to form a sample block with a thickness of 5mm±0.1mm and a height of 5mm±0.1mm. Mount the sample block on the TMA sample stage, ensuring close contact between the probe, the sample, and the sample stage, and apply pressure along the sample axis. Start at 20℃, with a heating rate of 10℃ / min, and begin scanning at 220℃. After scanning, obtain the thickness versus temperature test curve. Within the specified temperature range, in the relatively linear portion, such as the pre-glass transition and post-glass transition sections, calculate the respective linear thermal expansion coefficients α1 and α2 according to the formulas. The calculation formula for α1 is shown in Equation I, and the calculation formula for α2 is shown in Equation II.

[0085] Formula I

[0086] In Equation I, α1 is the linear expansion coefficient before the glass transition temperature; H A H represents the sample thickness at point A on the curve, in mm. B T represents the sample thickness at point B on the curve, in mm. A T represents the temperature at point A on the curve, in degrees Celsius (°C). B The temperature at point B on the curve is expressed in °C.

[0087] Formula II

[0088] In Equation II, α2 is the linear expansion coefficient after the glass transition temperature; H C H represents the sample thickness at point C on the curve, in mm. D T represents the sample thickness at point D on the curve, in mm. C T represents the temperature at point C on the curve, in degrees Celsius (°C). D The temperature at point D on the curve is expressed in °C.

[0089] As shown in Tables 3 and 4, even with high filler content, the epoxy resin composition provided by this invention still exhibits a long gelation time and helical flow constant, indicating that the epoxy resin composition still possesses good processing performance. The dielectric constant of the epoxy resin composition provided by this invention remains at a conventional level, and the dielectric loss can reach below 0.002 (2.5 GHz), which is extremely beneficial for the signal reception of devices. At the same time, the epoxy resin composition provided by this invention has a relatively low water absorption rate, which allows the product to have better reliability and better adapt to high-humidity working environments. The epoxy resin composition provided by this invention has a high glass transition temperature, which is beneficial for passing some tests involving high temperatures and for its use in high-temperature working environments. The epoxy resin composition provided by this application has a low coefficient of thermal expansion, which can better protect internal devices and allow the molding compound to have good delamination performance and better reliability.

[0090] A physical image of the epoxy resin composition prepared in Example 3 of this invention is shown below. Figure 1 As shown; a physical image of the epoxy resin composition prepared in Example 8 is shown. Figure 2 As shown. By Figures 1-2 As can be seen, the present invention can prepare epoxy resin compositions of different colors as needed, and the epoxy resin compositions obtained have no defects such as pores, indicating that they have good processability.

[0091] Based on the above analysis, it can be seen that by using high-dosage low-dielectric-loss SiO2 micro powder as filler, and modifying it with epoxy resin, phenolic resin and low-dielectric-loss resin, the present invention can achieve the target of 0.002 dielectric loss of epoxy resin composition at 2.5GHz. At the same time, if there is a requirement for the appearance color of the product, a specific colorant can be used without affecting the dielectric loss of epoxy resin composition.

[0092] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. An epoxy resin composition with low dielectric loss, comprising the following components in mass percentage: filler 85~95%, epoxy resin 1~10%, phenolic resin 1~10%, low dielectric loss resin ≤5%, curing accelerator 0.1~0.8%, release agent 0.1~1%, coupling agent 0.1~0.8% and additive 0.2~1%; The low dielectric loss resin comprises any one or several of benzocyclobutene resin, modified polyurethane resin, polyphenyl ether, modified epoxy resin composition, polysiloxane hybrid resin, polyimide resin, maleimide resin, benzoxazine and fluorine-containing epoxy resin; The filler is low dielectric loss SiO2 micro powder; the standard of the low dielectric loss SiO2 micro powder is as follows: ； The preparation method of the epoxy resin composition with low dielectric loss comprises the following steps: (1) uniformly mixing the filler, epoxy resin, phenolic resin, low dielectric loss resin, curing accelerator, release agent, coupling agent and additive to obtain a premix; (2) mixing and extruding the premix obtained in step (1), and then cooling and crushing to obtain the epoxy resin composition with low dielectric loss; The temperature of the mixing and extruding is: first zone 40℃, second zone 60℃, third zone 140℃, fourth zone 100℃, fifth zone 70℃; The additive comprises any one or several of methyltrimethoxysilane, epoxy silane epoxy resin and epoxidized cyclized 1,3-butadiene.

2. The dielectric loss low epoxy resin composition according to claim 1, characterized by, The epoxy resin comprises any one or more of BP epoxy resin, MAR epoxy resin, EOCN epoxy resin, DCPD epoxy resin and MFN epoxy resin.

3. The dielectric loss low epoxy resin composition according to claim 1, characterized by, The phenolic resin comprises any one or more of MAR phenolic resin, XYLOK phenolic resin, PN phenolic resin and MFN phenolic resin.

4. The dielectric loss low epoxy resin composition according to claim 1, characterized by, The curing accelerator comprises any one or several of 4,5-bis(hydroxymethyl)-2-phenyl-1H-imidazole, 4-hydroxymethyl-5-methyl-2-phenylimidazole, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-S-triazine, N,N-dimethylbenzylamine, phenyldimethylamine, triphenylphosphine and triphenylphosphine-1,4-benzoquinone adduct.

5. The dielectric loss low epoxy resin composition according to claim 1, characterized by, The release agent comprises any one or several of polyethylene wax, oxidized polyethylene wax, montan E wax, Fischer-Tropsch synthesis wax, vegetable wax, fatty acid glyceride wax and maleic anhydride grafted modified wax.

6. The dielectric loss low epoxy resin composition according to claim 1, characterized by, The coupling agent is a silane coupling agent; the silane coupling agent comprises any one or several of 3-(2,3-epoxypropoxy)propyltrimethoxysilane, 3-(phenylamino)propyltrimethoxysilane and mercaptopropyltrimethoxysilane.

7. The dielectric loss low epoxy resin composition according to claim 1, characterized by, The epoxy resin composition with low dielectric loss further comprises ≤1% colorant in mass percentage; the colorant comprises any one or several of iron yellow, carbon black, black sphere, titanium dioxide, ZnO and zinc white.

8. The method of producing the epoxy resin composition having low dielectric loss according to any one of claims 1 to 7, characterized by, The preparation method comprises the following steps: (1) uniformly mixing the filler, epoxy resin, phenolic resin, low dielectric loss resin, curing accelerator, release agent, coupling agent and additive to obtain a premix; (2) The premixture obtained in the step (1) is subjected to mixing and extrusion, and then cooled and pulverized to obtain an epoxy resin composition having a low dielectric loss.

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