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CN-121991615-A - Conductive adhesive for epoxy FOG-ACF, and preparation method and application thereof

CN121991615ACN 121991615 ACN121991615 ACN 121991615ACN-121991615-A

Abstract

The invention discloses a conductive adhesive for epoxy FOG-ACF, and a preparation method and application thereof, and belongs to the technical field of electronic packaging materials. The preparation method of the conductive adhesive comprises the steps of carrying out ultrasonic dispersion on conductive particles to form a suspension, carrying out high-speed shearing pretreatment on fumed silica to form slurry, carrying out planetary stirring mixing and dispersion on the suspension and the slurry and the polar modified crosslinked polymer, the epoxy resin, the silane coupling agent, the dispersing agent, the filler and the curing agent which are prepared by a specific method, and finally, carrying out defoaming filtration to obtain the finished product. The polar modified cross-linked polymer is synthesized by ring-opening esterification of acrylic acid monomer and polyfunctional epoxy compound to obtain polyhydroxy acrylate intermediate, and free radical copolymerization of polyhydroxy acrylate intermediate obtained by polyurethane esterification of hydroxyl-containing acrylate monomer and diisocyanate.

Inventors

  • ZHU LINGJIE
  • QU LIANGDUAN
  • ZHI WEIQIANG
  • CHEN MING

Assignees

  • 古泰(江苏)新材料有限公司

Dates

Publication Date
20260508
Application Date
20260202

Claims (10)

  1. 1. The preparation method of the conductive adhesive for the epoxy FOG-ACF is characterized by comprising the following steps of: s1, conducting particles are subjected to dispersion treatment to obtain a conducting particle suspension; s2, preprocessing the fumed silica to obtain fumed silica slurry; s3, mixing and dispersing the conductive particle suspension, the fumed silica slurry, the polar modified crosslinked polymer, the epoxy resin, the silane coupling agent, the dispersing agent, the filler, the solvent and the curing agent to obtain conductive adhesive slurry; S4, conducting glue sizing agent is defoamed and filtered to obtain the conducting glue for the epoxy FOG-ACF; the preparation method of the polar modified crosslinked polymer comprises the following steps: m1, carrying out ring-opening esterification reaction on an acrylic monomer and a multifunctional epoxy compound to obtain a polyhydroxy acrylic ester intermediate; M2, performing polyurethane reaction on acrylate monomer containing hydroxyl and diisocyanate to obtain a polyurethane acrylate intermediate; And M3, carrying out free radical copolymerization reaction on the polyhydroxy acrylic ester intermediate and the polyurethane acrylic ester intermediate to obtain the polar modified crosslinked polymer.
  2. 2. The method according to claim 1, wherein in the step M1, the acrylic monomer comprises one or more of acrylic acid and methacrylic acid in an amount of 10 to 50 parts by weight; The multifunctional epoxy compound comprises 5-60 parts by weight of one or more of trimethylolpropane triglycidyl ether, glycerol triglycidyl ether and pentaerythritol tetraglycidyl ether; the ring-opening esterification reaction is carried out in an organic solvent, the reaction temperature is 80-100 ℃, and the reaction time is 1.5-3h.
  3. 3. The preparation method according to claim 1, wherein in the step M2, the acrylate monomer comprises one or more of hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, and 4-hydroxybutyl acrylate, and the weight part is 10-50; the diisocyanate comprises one or more of isophorone diisocyanate, hexamethylene diisocyanate, toluene diisocyanate and diphenylmethane diisocyanate, and the weight part of the diisocyanate is 5-60 parts; The polyurethane reaction is carried out in the presence of an organotin catalyst and an organic solvent, the reaction temperature is 80-95 ℃, and the reaction time is 2.5-4h.
  4. 4. The preparation method according to claim 1, wherein in the step M3, 5 to 30 parts by weight of the polyhydroxyl acrylate intermediate, 3 to 40 parts by weight of the polyurethane acrylate intermediate and the organic peroxide thermal initiator are mixed, heated to 90 to 110 ℃, and then a mixed solution composed of 10 to 30 parts by weight of the multifunctional acrylate crosslinking agent and 5 to 25 parts by weight of the monofunctional acrylate reactive diluent is dropwise added, and the mixture is kept warm and continuously reacted for 2 to 4 hours after the completion of the dropwise addition, thereby obtaining the polar modified crosslinked polymer.
  5. 5. The method according to claim 1, wherein in step S1, 1 to 20 parts by weight of the conductive particles are dissolved in 5 to 15 parts by weight of a solvent to perform ultrasonic dispersion treatment, the ultrasonic power is 200 to 500W, and the ultrasonic treatment time is 2 to 4min.
  6. 6. The preparation method according to claim 1, wherein in step S2, 3 to 10 parts by weight of the hydrophobic fumed silica is dissolved in 5 to 15 parts by weight of the solvent, and the mixture is subjected to shearing dispersion at a rotation speed of 1000 to 3000rpm for a treatment time of 5 to 15 minutes.
  7. 7. The preparation method according to claim 1, wherein in step S3, each component comprises, by weight, 1-20 parts of conductive particles added as a conductive particle suspension, 3-10 parts of fumed silica added as a fumed silica slurry, 2-6 parts of a polar modified crosslinked polymer, 2-10 parts of an epoxy resin, 2-10 parts of a silane coupling agent, 1-10 parts of a dispersing agent, 30-70 parts of a filler, and 1-10 parts of a curing agent; The mixing and dispersing treatment adopts a planetary stirrer, firstly, stirring for 5-15min at a revolution speed of 100-300rpm and a rotation speed of 200-500rpm, then dispersing for 30-60min at a revolution speed of 500-800rpm and a rotation speed of 1000-1500rpm, finally, adding a curing agent when the temperature is lower than 50 ℃, and continuing stirring for 5-10min at a revolution speed of 200-400rpm and a rotation speed of 500-800 rpm.
  8. 8. The method according to claim 1, wherein in step S4, the conductive paste is subjected to defoaming treatment under a vacuum of less than-0.095 MPa for 10 to 30 minutes, and the defoamed paste is filtered by using a 100 to 400 mesh filter.
  9. 9. An electroconductive adhesive for epoxy FOG-ACF, characterized by being prepared by the preparation method of any one of claims 1 to 8.
  10. 10. Use of the conductive paste for epoxy FOG-ACF according to claim 9 in connection with electrodes of electronic components, wherein the conductive paste for epoxy FOG-ACF is cured by a thermo-compression process and an anisotropic conductive connection is formed between the electrodes.

Description

Conductive adhesive for epoxy FOG-ACF, and preparation method and application thereof Technical Field The invention belongs to the technical field of electronic packaging materials, and particularly relates to a conductive adhesive for epoxy FOG-ACF, and a preparation method and application thereof. Background The anisotropic conductive Adhesive (ACF) is used as a key electronic packaging material and is widely applied to electrode interconnection of precision devices such as a thin film transistor liquid crystal display, chip glass, a flexible circuit board and the like. Among them, epoxy resin becomes the most commonly used matrix resin in ACF system by virtue of its excellent adhesive property, mechanical strength and curing reliability. However, conventional ACFs based on epoxy resins still face challenges in practical applications. On the one hand, the limited physical adsorption of the epoxy resin itself to the surface of different substrates makes it difficult for the interface bond strength to meet the increasingly higher reliability requirements, especially under thermal cycling or mechanical stress, the interface may become a weak link to failure. On the other hand, in order to achieve stable anisotropic conduction, the conductive paste needs to form a reliable conductive path in the vertical direction while ensuring reliable insulation in the horizontal direction. This requires that the conductive particles be uniformly dispersed in the resin matrix and effectively trapped and pressed between the upper and lower electrodes during the hot pressing process. In the prior art, the content of conductive particles is increased or the curing process parameters are adjusted, but the former may damage the manufacturability and mechanical properties of the adhesive film, and the latter is limited by the temperature resistance limit of components. Therefore, how to further improve the interface bonding quality and optimize the formation of the conductive channels while maintaining the inherent advantages of the epoxy resin system is a technical problem of continued interest in the art. Disclosure of Invention The invention overcomes the defects of the prior art and provides a conductive adhesive for epoxy FOG-ACF, and a preparation method and application thereof. In order to achieve the purpose, the technical scheme adopted by the invention is that the preparation method of the conductive adhesive for the epoxy FOG-ACF comprises the following steps: s1, conducting particles are subjected to dispersion treatment to obtain a conducting particle suspension; s2, preprocessing the fumed silica to obtain fumed silica slurry; s3, mixing and dispersing the conductive particle suspension, the fumed silica slurry, the polar modified crosslinked polymer, the epoxy resin, the silane coupling agent, the dispersing agent, the filler, the solvent and the curing agent to obtain conductive adhesive slurry; and S4, conducting defoaming and filtering treatment on the conductive adhesive slurry to obtain the conductive adhesive for the epoxy FOG-ACF. The preparation method of the polar modified crosslinked polymer comprises the following steps: m1, carrying out ring-opening esterification reaction on an acrylic monomer and a multifunctional epoxy compound to obtain a polyhydroxy acrylic ester intermediate; M2, performing polyurethane reaction on acrylate monomers and diisocyanate to obtain a polyurethane acrylate intermediate; And M3, carrying out free radical copolymerization reaction on the polyhydroxy acrylic ester intermediate and the polyurethane acrylic ester intermediate to obtain the polar modified crosslinked polymer. Further, in the step M1, the acrylic acid monomer comprises one or more of acrylic acid and methacrylic acid, 10-50 parts by weight, the multifunctional epoxy compound comprises one or more of trimethylolpropane triglycidyl ether, glycerol triglycidyl ether and pentaerythritol tetraglycidyl ether, 5-60 parts by weight, the ring-opening esterification reaction is carried out in an organic solvent, the reaction temperature is 80-100 ℃, and the reaction time is 1.5-3 hours. Further, in the step M2, the acrylate monomer comprises 10-50 parts by weight of one or more of hydroxyethyl acrylate, hydroxypropyl acrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate and 4-hydroxybutyl acrylate, the diisocyanate comprises 5-60 parts by weight of one or more of isophorone diisocyanate, hexamethylene diisocyanate, toluene diisocyanate and diphenylmethane diisocyanate, and the urethanization reaction is performed in the presence of an organotin catalyst and an organic solvent, the reaction temperature is 80-95 ℃, and the reaction time is 2.5-4 hours. Further, in the step M3, 5-30 parts by weight of polyhydroxy acrylic ester intermediate and 3-40 parts by weight of polyurethane acrylic ester intermediate are mixed with an organic peroxide thermal initiator, heated to 90-110 ℃, and then mixed solution consisting