Single-component low-viscosity glue-overflow-free epoxy resin electronic glue and preparation method thereof

Abstract

The invention discloses a single-component low-viscosity glue-overflow-free epoxy resin electronic glue which is characterized by comprising the following components in parts by weight: 25-40 parts of epoxy resin, 0.5-2.5 parts of thermoplastic resin, 20-35 parts of a curing agent, 1-10 parts of an auxiliary agent, 15-40 parts of filler and 0.5-5 parts of an accelerant. According to the single-component low-viscosity glue-overflow-free epoxy resin electronic glue and the preparation method thereof provided by the invention, the thermoplastic resin is added into a system, so that the problems that a chip is polluted due to glue overflow in glue dispensing, wire drawing and heating curing processes, and the periphery of the chip is cracked due to large shrinkage rate after the overflowing glue is cured in a severe case can be effectively solved. Meanwhile, the system does not contain an organic solvent, volatile organic compounds are hardly released in the dispensing and curing processes, the problem of solvent residue is avoided, and the content of ion impurities is extremely low. The prepared epoxy resin electronic glue system has the advantages of low viscosity, no glue overflow after curing, no solvent addition and no VOC (volatile organic compound) addition.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of epoxy resin electronic adhesive, and particularly relates to a single-component low-viscosity non-glue-overflowing epoxy resin electronic adhesive and a preparation method thereof. BACKGROUND

[0002] The epoxy resin electronic adhesive has good adhesion, small shrinkage and excellent temperature resistance, and can maintain stable bonding effect in various harsh environments. In addition, the epoxy resin electronic adhesive also has the characteristics of insulation, moisture resistance, shock resistance and the like, and can effectively protect electronic components from interference and damage from external factors. At present, the single-component epoxy resin electronic adhesive applied to electronic components requires to realize rapid dispensing at room temperature and cannot appear the phenomenon of wire drawing during the dispensing process, and the glue cannot overflow after curing. This puts higher requirements on the normal temperature viscosity and high temperature viscosity of the epoxy resin electronic adhesive. On the one hand, it is required to have a lower dynamic viscosity at room temperature, which is beneficial to the flow of glue and rapid filling. When the viscosity of the adhesive exceeds a certain range, not only the dispensing efficiency is reduced, but also the needle head is easily blocked. On the other hand, it is required to ensure that the viscosity of the adhesive decreases too fast under the curing condition, otherwise the glue overflow is easily caused by the rapid decrease of the viscosity of the glue during the heating process, which causes pollution to the chip, and the chip is cracked around due to the large shrinkage of the overflowed glue after solidification. In addition, some brands of epoxy resin electronic adhesives also have the problems of high curing temperature and long time, insufficient adhesive strength after long-term aging test of the glue, and solvent residue affecting the quality and safety of the final product. These problems may cause the electronic components to be separated from the substrate under the action of thermal cycle or mechanical stress, resulting in packaging failure.

[0003] In the prior art, patent CN116606619A discloses a preparation method of a single-component epoxy resin electronic encapsulating adhesive. The curing agent system is obtained by reacting 4,4'-stilbene dicarboxylic acid, exo-3,6-epoxy-1,2,3,6-tetrahydrobenzene dicarboxylic acid, and 2,3-benzene dicarboxylic acid with vanadyl sulfate, respectively, to obtain an organic vanadium metal complex mixture. N-vinylimidazole is polymerized with the organic vanadium metal complex of 4,4'-stilbene dicarboxylic acid, and the solvent DMF needs to be removed subsequently. The preparation process is complex, and there is no mention of using a thermoplastic polymer to improve the high-temperature viscosity change of the adhesive. Patent CN106928892A discloses a single-component epoxy resin electronic adhesive, a preparation method and application thereof. The method mentions using a thermoplastic acrylic resin to improve the bonding performance of the adhesive in combination with the epoxy resin. Although it is a single component, it does not have low viscosity. Patent CN117603642A discloses a preparation method of a modified epoxy resin electronic adhesive. Although the modified electronic adhesive prepared by the method has excellent self-repairing performance and flame retardant performance, the preparation process involves multiple solvents such as cyclohexanone, acetone and N,N-dimethylformamide, which cannot be avoided during the curing process of the adhesive. SUMMARY

[0004] An object of the present application is to solve at least the above problems and / or defects, and to provide at least the advantages to be described later.

[0005] To achieve these objects and other advantages according to the present application, a single-component low-viscosity non-overflow epoxy resin electronic adhesive is provided, which comprises the following components by weight: epoxy resin 25-40 parts, thermoplastic resin 0.5-2.5 parts, curing agent 20-35 parts, additive 1-10 parts, filler 15-40 parts, and accelerator 0.5-5 parts.

[0006] Preferably, the epoxy resin is one of bisphenol A type epoxy resin, bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, alicyclic epoxy resin, multifunctional epoxy resin, or a combination of at least two of them.

[0007] Preferably, the thermoplastic resin is one of polyvinyl butyral ester, phenoxy resin, thermoplastic polyurethane, acrylic resin, polyolefin, polyester resin, or a combination of at least two of them.

[0008] Preferably, the curing agent is one of dicyandiamide, phthalic anhydride, methyl tetrahydrophthalic anhydride, tetrahydrophthalic anhydride, methyl hexahydrophthalic anhydride, hexahydrophthalic anhydride, or a combination of at least two of them.

[0009] Preferably, the additive is one of silane coupling agent, titanate coupling agent, aluminate coupling agent, defoaming agent, leveling agent, or a combination of at least two of them.

[0010] Preferably, the filler is one or a combination of at least two of nano calcium carbonate, diatomite, montmorillonite, silicon powder, and carbon black.

[0011] Preferably, the accelerator is a quaternary ammonium salt organic compound or an imidazole adduct.

[0012] The application also provides a preparation method of the single-component low-viscosity non-glue-overflowing epoxy resin electronic adhesive, comprising the following steps: Step one, the epoxy resin and the thermoplastic resin are added into a reaction kettle and stirred for 30 minutes at a stirring speed of 5-15 rpm, and the temperature in the kettle is controlled at 50℃±1℃ by opening the condensate water; the additives and the curing agent are added into the above components and stirred for 30 minutes at a stirring speed of 5-15 rpm, and the temperature in the kettle is controlled at 50℃±1℃; Step two, the filler is added into the reaction kettle and dispersed at a high speed for 30 minutes at a stirring speed of 5-15 rpm and a dispersion speed of 1500-2000 rpm, and the temperature in the kettle is controlled at 50℃±1℃; the accelerator is added into the reaction kettle and dispersed at a high speed for 30 minutes at a stirring speed of 5-15 rpm and a dispersion speed of 1500-2000 rpm, and the temperature in the kettle is monitored and controlled at 50℃±1℃; Step three, after the reaction is completed, the cooling water is turned off, and the material is filtered, then vacuum degassing is carried out at room temperature for 20 minutes at a vacuum degree of ≥-0.8 MPa, and finally the final product is packaged.

[0013] The application at least has the following beneficial effects: the single-component low-viscosity non-glue-overflowing epoxy resin electronic adhesive and the preparation method thereof provided by the application can effectively solve the problems of glue overflow during dispensing and curing, which causes contamination of the chip and even cracks around the chip due to the large shrinkage rate of the cured glue, by adding the thermoplastic resin in the system, and the system does not contain organic solvents, almost no volatile organic compounds are released during dispensing and curing, there is no solvent residue problem, and the ion impurity content is extremely low. The prepared epoxy resin electronic adhesive system has the advantages of low viscosity, no glue overflow after curing, no solvent addition, and no VOC addition.

[0014] Other advantages, objects, and features of the application will be apparent from the following description, and will be understood by those skilled in the art through practice of the application. DETAILED DESCRIPTION

[0015] The application will be further described in detail below, so that those skilled in the art can implement it according to the description.

[0016] Example 1 Step one, according to the weight parts, 35 parts of bisphenol A type epoxy resin and 0.5 parts of polyvinyl butyral ester are added into the reaction kettle and stirred for 30 minutes, the stirring speed is 10 rpm, and the condensate water is opened to control the temperature in the kettle at 50℃±1℃; 1 part of silane coupling agent, 25 parts of tetrahydrophthalic anhydride are added into the above components and stirred for 30 minutes, the stirring speed is 10 rpm, and the temperature in the kettle is controlled at 50℃±1℃; Step two, 3 parts of calcium carbonate, 32 parts of silicon powder, and 0.5 parts of carbon black are added into the reaction kettle and dispersed by high-speed stirring for 30 minutes, the stirring speed is 10 rpm, and the dispersion speed is 1800 rpm, the temperature in the kettle is controlled at 50℃±1℃; 2 parts of benzyl triethyl ammonium chloride are added into the reaction kettle and dispersed by high-speed stirring for 30 minutes, the stirring speed is 10 rpm, and the dispersion speed is 1800 rpm, the temperature in the kettle is controlled at 50℃±1℃; Step three, after the reaction is completed, the cooling water is turned off and the material is filtered, then vacuum degassing at room temperature is carried out for 20 minutes, the vacuum degree is ≥-0.8MPa, and finally the final product is packaged.

[0017] Example 2 Step one, according to the weight parts, 35 parts of bisphenol A type epoxy resin and 1 part of polyvinyl butyral ester are added into the reaction kettle and stirred for 30 minutes, the stirring speed is 10 rpm, and the condensate water is opened to control the temperature in the kettle at 50℃±1℃; 1 part of silane coupling agent, 25 parts of tetrahydrophthalic anhydride are added into the above components and stirred for 30 minutes, the stirring speed is 10 rpm, and the temperature in the kettle is controlled at 50℃±1℃; Step two, 3 parts of calcium carbonate, 32 parts of silicon powder, and 0.5 parts of carbon black are added into the reaction kettle and dispersed by high-speed stirring for 30 minutes, the stirring speed is 10 rpm, and the dispersion speed is 1800 rpm, the temperature in the kettle is controlled at 50℃±1℃; 2 parts of benzyl triethyl ammonium chloride are added into the reaction kettle and dispersed by high-speed stirring for 30 minutes, the stirring speed is 10 rpm, and the dispersion speed is 1800 rpm, the temperature in the kettle is controlled at 50℃±1℃; Step three, after the reaction is completed, the cooling water is turned off and the material is filtered, then vacuum degassing at room temperature is carried out for 20 minutes, the vacuum degree is ≥-0.8MPa, and finally the final product is packaged.

[0018] Example 3 Step one, according to the weight parts, 35 parts of bisphenol A type epoxy resin and 2.5 parts of polyvinyl butyral ester are added into the reaction kettle and stirred for 30 minutes, the stirring speed is 10 rpm, and the condensate water is opened to control the temperature in the kettle at 50℃±1℃; 1 part of silane coupling agent, 25 parts of tetrahydrophthalic anhydride are added into the above components and stirred for 30 minutes, the stirring speed is 10 rpm, and the temperature in the kettle is controlled at 50℃±1℃; Step two, 3 parts of calcium carbonate, 32 parts of silica powder, 0.5 parts of carbon black are added into the reaction kettle for high speed stirring dispersion for 30 minutes, the stirring speed is 10 rpm, the dispersion speed is 1800 rpm, the kettle temperature is controlled at 50℃±1℃; 2 parts of benzyl triethyl ammonium chloride are added into the reaction kettle for high speed stirring dispersion for 30 minutes, the stirring speed is 10 rpm, the dispersion speed is 1800 rpm, the kettle temperature is controlled at 50℃±1℃; Step three, after the reaction is completed, the cooling water is turned off and the material is filtered, then vacuum degassing is carried out at room temperature for 20 minutes, the vacuum degree is ≥-0.8MPa, and finally the final product is packaged.

[0019] Example 4 Step one, according to the weight parts, 35 parts of bisphenol A type epoxy resin and 0.5 parts of phenoxy resin are added into the reaction kettle for fully stirring for 30 minutes, the stirring speed is 10 rpm, and the condensate water is opened at the same time to control the kettle temperature at 50℃±1℃; 1 part of silane coupling agent, 25 parts of tetrahydrophthalic anhydride are added into the above components for stirring for 30 minutes, the stirring speed is 10 rpm, and the kettle temperature is controlled at 50℃±1℃; Step two, 3 parts of calcium carbonate, 32 parts of silica powder, 0.5 parts of carbon black are added into the reaction kettle for high speed stirring dispersion for 30 minutes, the stirring speed is 10 rpm, the dispersion speed is 1800 rpm, the kettle temperature is controlled at 50℃±1℃; 2 parts of benzyl triethyl ammonium chloride are added into the reaction kettle for high speed stirring dispersion for 30 minutes, the stirring speed is 10 rpm, the dispersion speed is 1800 rpm, the kettle temperature is controlled at 50℃±1℃; Step three, after the reaction is completed, the cooling water is turned off and the material is filtered, then vacuum degassing is carried out at room temperature for 20 minutes, the vacuum degree is ≥-0.8MPa, and finally the final product is packaged.

[0020] Example 5 Step one, according to the weight parts, 35 parts of bisphenol A type epoxy resin and 2.5 parts of phenoxy resin are added into the reaction kettle for fully stirring for 30 minutes, the stirring speed is 10 rpm, and the condensate water is opened at the same time to control the kettle temperature at 50℃±1℃; 1 part of silane coupling agent, 25 parts of tetrahydrophthalic anhydride are added into the above components for stirring for 30 minutes, the stirring speed is 10 rpm, and the kettle temperature is controlled at 50℃±1℃; Step two, 3 parts of calcium carbonate, 32 parts of silica powder, 0.5 parts of carbon black were added into the reaction kettle for high-speed stirring dispersion for 30 minutes, the stirring speed was 10 rpm, the dispersion speed was 1800 rpm, the kettle temperature was controlled at 50℃±1℃; 2 parts of benzyl triethyl ammonium chloride were added into the reaction kettle for high-speed stirring dispersion for 30 minutes, the stirring speed was 10 rpm, the dispersion speed was 1800 rpm, and the kettle temperature was monitored and controlled at 50℃±1℃; Step three, after the reaction was completed, the cooling water was turned off and the material was filtered, then vacuum degassing was carried out at room temperature for 20 minutes, the vacuum degree was ≥-0.8MPa, and finally the final product was packaged.

[0021] Comparative example 1 Step one, according to weight parts, 35 parts of bisphenol A type epoxy resin, 1 part of silane coupling agent, 25 parts of tetrahydrophthalic anhydride were added into the reaction kettle for fully stirring for 30 minutes, the stirring speed was 10 rpm, and the condensate water was opened at the same time to control the kettle temperature at 50℃±1℃; Step two, 3 parts of calcium carbonate, 32 parts of silica powder, 0.5 parts of carbon black were added into the reaction kettle for high-speed stirring dispersion for 30 minutes, the stirring speed was 10 rpm, the dispersion speed was 1800 rpm, the kettle temperature was controlled at 50℃±1℃; 2 parts of benzyl triethyl ammonium chloride were added into the reaction kettle for high-speed stirring dispersion for 30 minutes, the stirring speed was 10 rpm, the dispersion speed was 1800 rpm, and the kettle temperature was monitored and controlled at 50℃±1℃; Step three, after the reaction was completed, the cooling water was turned off and the material was filtered, then vacuum degassing was carried out at room temperature for 20 minutes, the vacuum degree was ≥-0.8MPa, and finally the final product was packaged.

[0022] Comparative example 2 Step one, according to weight parts, 35 parts of bisphenol A type epoxy resin and 0.5 parts of methyl phenol type phenolic epoxy resin (thermosetting resin) were added into the reaction kettle for fully stirring for 30 minutes, the stirring speed was 10 rpm, and the condensate water was opened at the same time to control the kettle temperature at 50℃±1℃; Step two, 1 part of silane coupling agent, 25 parts of tetrahydrophthalic anhydride were added into the above components for stirring for 30 minutes, the stirring speed was 10 rpm, and the kettle temperature was controlled at 50℃±1℃; 3 parts of calcium carbonate, 32 parts of silica powder, 0.5 parts of carbon black were added into the reaction kettle for high-speed stirring dispersion for 30 minutes, the stirring speed was 10 rpm, the dispersion speed was 1800 rpm, the kettle temperature was controlled at 50℃±1℃; 2 parts of benzyl triethyl ammonium chloride were added into the reaction kettle for high-speed stirring dispersion for 30 minutes, the stirring speed was 10 rpm, the dispersion speed was 1800 rpm, and the kettle temperature was monitored and controlled at 50℃±1℃; Step three, after the reaction is completed, the cooling water is closed and the material is filtered, then vacuum degassing at room temperature for 20 minutes, vacuum degree≥-0.8MPa, finally packaging to get the final product.

[0023] Comparative Example 4 Step one, according to the weight parts, 35 parts of bisphenol A type epoxy resin and 1 part of methyl phenol type phenolic epoxy resin (thermosetting resin) are added into the reaction kettle for fully stirring for 30 minutes, the stirring speed is 10 rpm, and the condensate water is opened to control the temperature in the kettle at 50℃±1℃; Step two, 1 part of silane coupling agent, 25 parts of tetrahydrophthalic anhydride are added into the above components for stirring for 30 minutes, the stirring speed is 10 rpm, and the temperature in the kettle is controlled at 50℃±1℃; 3 parts of calcium carbonate, 32 parts of silicon powder, and 0.5 parts of carbon black are added into the reaction kettle for high-speed stirring and dispersion for 30 minutes, the stirring speed is 10 rpm, the dispersion speed is 1800 rpm, and the temperature in the kettle is controlled at 50℃±1℃; 2 parts of benzyl triethyl ammonium chloride are added into the reaction kettle for high-speed stirring and dispersion for 30 minutes, the stirring speed is 10 rpm, the dispersion speed is 1800 rpm, and the temperature in the kettle is controlled at 50℃±1℃; Step three, after the reaction is completed, the cooling water is closed and the material is filtered, then vacuum degassing at room temperature for 20 minutes, vacuum degree≥-0.8MPa, finally packaging to get the final product.

[0024] Comparative Example 4 Step one, according to the weight parts, 35 parts of bisphenol A type epoxy resin and 1 part of methyl phenol type phenolic epoxy resin (thermosetting resin) are added into the reaction kettle for fully stirring for 30 minutes, the stirring speed is 10 rpm, and the condensate water is opened to control the temperature in the kettle at 50℃±1℃; Step two, 1 part of silane coupling agent, 25 parts of tetrahydrophthalic anhydride are added into the above components for stirring for 30 minutes, the stirring speed is 10 rpm, and the temperature in the kettle is controlled at 50℃±1℃; 3 parts of calcium carbonate, 32 parts of silicon powder, and 0.5 parts of carbon black are added into the reaction kettle for high-speed stirring and dispersion for 30 minutes, the stirring speed is 10 rpm, the dispersion speed is 1800 rpm, and the temperature in the kettle is controlled at 50℃±1℃; 2 parts of benzyl triethyl ammonium chloride are added into the reaction kettle for high-speed stirring and dispersion for 30 minutes, the stirring speed is 10 rpm, the dispersion speed is 1800 rpm, and the temperature in the kettle is controlled at 50℃±1℃; Step three, after the reaction is completed, the cooling water is closed and the material is filtered, then vacuum degassing at room temperature for 20 minutes, vacuum degree≥-0.8MPa, finally packaging to get the final product.

[0025] The component and proportion of each component in Example 1-5 and Comparative Example 1-4 are shown in Table 1.

[0026] Table 1 Viscosity test was performed on Example 1-5 and Comparative Example 1-4, and the occurrence of stringing during dispensing was observed, and overflow was observed by electron microscope after curing. The test results are shown in Table 2.

[0027] Table 2 As can be seen from the test results of Example 1-5 and Comparative Example 1-4, Comparative Example 1 did not add thermoplastic resin, and the viscosity decreased too fast at high temperature, and overflow occurred; Comparative Example 2-3 changed the thermoplastic resin to an equal amount of thermosetting resin, compared with the thermosetting resin, the thermoplastic resin formed a physical network of entanglement due to its long-chain structure melting at high temperature, which hindered the overall movement of the thermosetting molecular chain, so that the viscosity of the glue solution decreased slowly, and no overflow occurred, reducing the pollution to the chip; Comparative Example 4 compared with Example 3, when the content of thermoplastic resin was higher than 2.5 parts, the viscosity at low temperature was too high, and dispensing stringing occurred, and the preferred range of thermoplastic resin was 0.5-2.5 parts.

[0028] Although the embodiments of the present application have been disclosed as above, it is not limited to the application listed in the specification and the embodiments, and can be fully applied to various fields suitable for the present application, and additional modifications can be easily realized by those skilled in the art, and therefore the present application is not limited to specific details, without departing from the general concept defined by the claims and the equivalent scope.

Claims

1. A one-component low-viscosity, non-overflow epoxy resin electronic adhesive, characterized in that: The invention comprises the following components in parts by weight: 25 to 40 parts of epoxy resin, 0.5 to 2.5 parts of thermoplastic resin, 20 to 35 parts of curing agent, 1 to 10 parts of auxiliary agent, 15 to 40 parts of filler and 0.5 to 5 parts of accelerator.

2. The one-component low-viscosity, non-overflow epoxy resin electronic adhesive as claimed in claim 1, characterized in that: The epoxy resin is one or a combination of at least two of bisphenol A epoxy resin, bisphenol F epoxy resin, hydrogenated bisphenol A epoxy resin, alicyclic epoxy resin, and multifunctional epoxy resin.

3. The one-component low-viscosity, non-overflow epoxy resin electronic adhesive as claimed in claim 1, characterized in that: The thermoplastic resin is one or a combination of at least two of polyvinyl butyral, phenoxy resin, thermoplastic polyurethane, acrylic resin, polyolefin, and polyester resin.

4. The one-component low-viscosity, non-overflow epoxy resin electronic adhesive as claimed in claim 1, characterized in that: The curing agent is one or a combination of at least two of dicyandiamide, phthalic anhydride, methyltetrahydrophthalic anhydride, tetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, and hexahydrophthalic anhydride.

5. The one-component low-viscosity, non-overflow epoxy resin electronic adhesive as claimed in claim 1, characterized in that: The auxiliary agent is one or a combination of at least two of a silane coupling agent, a titanate coupling agent, an aluminate coupling agent, a defoaming agent, and a leveling agent.

6. The one-component low-viscosity, non-overflow epoxy resin electronic adhesive as claimed in claim 1, characterized in that: The filler is one of nano calcium carbonate, diatomaceous earth, montmorillonite, silica powder, and carbon black, or a combination of at least two of them.

7. The one-component low-viscosity, non-overflow epoxy resin electronic adhesive as claimed in claim 1, characterized in that: The accelerator is a quaternary ammonium salt organic compound or an imidazole adduct.

8. A method for preparing the one-component low-viscosity, non-overflow epoxy resin electronic adhesive according to any one of claims 1 to 7, characterized in that: The following steps are involved: Step 1: Add epoxy resin and thermoplastic resin into the reaction kettle and stir thoroughly for 30 minutes at a stirring speed of 5-15 rpm. At the same time, turn on the condensation water to control the temperature in the kettle at 50°C ± 1°C. Add auxiliary agent and curing agent to the above components and stir thoroughly for 30 minutes at a stirring speed of 5-15 rpm. Control the temperature in the kettle at 50°C ± 1°C. Step 2: Add the filler into the reactor and stir and disperse it at high speed for 30 minutes at a stirring speed of 5 to 15 rpm and a dispersion speed of 1500 to 2000 rpm, and control the temperature in the reactor at 50°C ± 1°C; add the accelerator into the reactor and stir and disperse it at high speed for 30 minutes at a stirring speed of 5 to 15 rpm and a dispersion speed of 1500 to 2000 rpm, and monitor the temperature in the reactor at 50°C ± 1°C; Step 3: After the reaction is completed, turn off the cooling water and filter the material, then perform vacuum degassing at room temperature for 20 minutes, with a vacuum degree of ≥-0.8MPa, and finally package to obtain the final product.

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