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CN-121991619-A - Adhesive, bonded permanent magnet and preparation method thereof

CN121991619ACN 121991619 ACN121991619 ACN 121991619ACN-121991619-A

Abstract

The invention discloses an adhesive, a bonded permanent magnet, a preparation method and application thereof. The adhesive is prepared from the following raw materials, by weight, 35-60 parts of a first curing resin, 10-40 parts of a second curing resin, 2-5 parts of a photoinitiator, 0.1-0.5 part of a photosensitizer, 2-8 parts of a nitrogenous organic curing agent, 5-20 parts of a reactive diluent, 0.1-0.5 part of a defoaming agent, 0.02-0.1 part of a polymerization inhibitor and 0.2-0.5 part of an antioxidant. The adhesive can enable the raw materials of the bonded permanent magnet to be rapidly cured under the irradiation of infrared light and ultraviolet light, so that the preparation time is obviously shortened, and the prepared bonded permanent magnet has higher dimensional accuracy, excellent deformation resistance and better magnetic property.

Inventors

  • LIAO YIJUN
  • YUAN WENJIE
  • DONG YI
  • ZHOU MINGCHEN
  • WU SHUJIE
  • WU ZHIMIN
  • SONG JINGJING
  • HAN FEI
  • YUAN YI
  • CHEN YA

Assignees

  • 包头天和磁材科技股份有限公司

Dates

Publication Date
20260508
Application Date
20260212

Claims (10)

  1. 1. The adhesive is characterized by being prepared from the following raw materials in parts by weight: 35-60 parts by weight of a first curing resin, 10-40 parts by weight of a second curing resin, 2-5 parts by weight of a photoinitiator, 0.1-0.5 part by weight of a photosensitizer, 2-8 parts by weight of a nitrogen-containing organic curing agent, 5-20 parts by weight of a reactive diluent, 0.1-0.5 part by weight of a defoaming agent, 0.02-0.1 part by weight of a polymerization inhibitor and 0.2-0.5 part by weight of an antioxidant; The first curing resin consists of at least one of epoxy acrylate resin and phenolic epoxy acrylate resin according to a weight ratio of 2-3:1, wherein the resin A is at least one of polyurethane acrylate resin and polyether acrylate resin, the second curing resin is at least one of bisphenol A epoxy resin and cycloaliphatic epoxy resin, the photoinitiator is at least one of acylphosphine oxide with an absorption wavelength of 320-405 nm, the light sensitizer is at least one of tin antimony oxide, indium tin oxide, titanium dioxide and zinc oxide, the nitrogen-containing organic curing agent is at least one of dicyandiamide, substituted dicyandiamide and dicarboxylic dihydrazide, the active diluent is at least one of trimethylolpropane triacrylate and pentaerythritol triacrylate according to a weight ratio of 0.5-2:1, the diluent B is at least one of tripropylene glycol diacrylate and 1, 6-hexanediol diacrylate, the antioxidant is at least one of p-phenylene diamine, and the antioxidant is at least one of p-phenylene diamine.
  2. 2. The adhesive of claim 1, wherein: The bisphenol A type epoxy resin is at least one selected from E20, E44, E51 and F48 type epoxy resins, and the cycloaliphatic epoxy resin is at least one selected from CY179, CY184, ERL-4201, ERL-4206 and ERL-4221 type epoxy resins; The acyl phosphine oxide with the absorption wavelength of 320-405 nm is at least one selected from a photoinitiator 819, a photoinitiator TPO-L and a photoinitiator TMO; The substituted dicyandiamide is at least one of 3, 5-disubstituted aniline modified dicyandiamide and epoxypropane modified dicyandiamide; The organic silicon defoamer is at least one selected from polydimethylsiloxane, polyether modified siloxane, fluorine modified siloxane and ethylene glycol siloxane, and the non-silicon polymer defoamer is at least one selected from GP, GPE, GPES type polyether defoamer; The hindered phenol antioxidant is at least one selected from the group consisting of antioxidant 1076, antioxidant 264, antioxidant 1010 and antioxidant 330, and the phosphite antioxidant is at least one selected from the group consisting of antioxidant 168, antioxidant 2103, antioxidant 3010 and TNPP.
  3. 3. A method of preparing the adhesive according to claim 1 or 2, comprising the steps of: A) Preparing a first curing resin, a second curing resin, a photoinitiator, a photosensitizing agent, a nitrogenous organic curing agent, a reactive diluent, a defoaming agent, a polymerization inhibitor and an antioxidant raw material; b) And C), mixing the raw materials prepared in the step A) at 15-40 ℃ under the condition of shielding gas to obtain the adhesive.
  4. 4. The method according to claim 3, wherein in the step B), the mixing time is 30 to 180 minutes.
  5. 5. Use of the adhesive according to claim 1 or 2 for reducing the curing time during the preparation of bonded permanent magnets and/or for improving the dimensional accuracy, deformation resistance and magnetic properties of the resulting bonded permanent magnets.
  6. 6. A bonded permanent magnet, characterized in that the bonded permanent magnet is made of a raw material comprising a permanent magnet alloy powder and the binder of claim 1 or 2.
  7. 7. The bonded permanent magnet of claim 6, wherein the bonded permanent magnet is made from raw materials comprising, by weight: 94-99 parts by weight of permanent magnet alloy powder, 1-4 parts by weight of the binder of claim 1 or 2, 0.2-1 part by weight of a silane coupling agent and 0.1-0.3 part by weight of a lubricant; the permanent magnet alloy powder is selected from powder of at least one of neodymium iron boron, samarium cobalt, alnico, ferrite and samarium iron nitrogen, the silane coupling agent is selected from at least one of KH550, KH560, KH570 and DL602, and the lubricant is selected from at least one of zinc stearate, aluminum stearate, calcium stearate, polyvinyl butyral, N' -ethylene bis stearamide and silicone oil.
  8. 8. A method of producing a bonded permanent magnet according to claim 7, comprising the steps of: 1) Mixing, grinding and sieving permanent magnet alloy powder, the binder, the silane coupling agent and the lubricant according to claim 1 or 2, and taking undersize powder to obtain a mixture; 2) Filling the mixture into a die, and pressing the mixture at 15-50 ℃ to obtain a permanent magnet green body; 3) The method comprises the steps of firstly heating a permanent magnet green body under the conditions of irradiation of infrared light with the wavelength of 800-1200 nm and control of the irradiation temperature to 60-120 ℃ to obtain a preheated permanent magnet green body, secondly performing ultraviolet irradiation on the preheated permanent magnet green body under the conditions of ultraviolet light with the wavelength of 320-405 nm and the intensity of 100-300 mW/cm < 2 >, obtaining an ultraviolet cured permanent magnet green body, secondly performing secondary heating on the ultraviolet cured permanent magnet green body under the conditions of irradiation of infrared light with the wavelength of 800-1200 nm and control of the irradiation temperature to obtain a cured permanent magnet, and cooling the cured permanent magnet to obtain the bonded permanent magnet.
  9. 9. The method of manufacturing according to claim 8, wherein: In the step 1), the mesh number of the sieving is 30-2500 meshes; in the step 2), the ambient humidity of the pressing is less than or equal to 40% RH.
  10. 10. The method according to claim 8, wherein in step 3): The time of the first heating is 1-15 min; the ultraviolet irradiation is performed within 3min after the first heating is finished, or the ultraviolet irradiation is performed under the conditions that the wavelength is 800-1200 nm of infrared light irradiation and the irradiation temperature is controlled to be 60-100 ℃, and the ultraviolet irradiation time is 10-120 s; the second heating time is 2-60 min.

Description

Adhesive, bonded permanent magnet and preparation method thereof Technical Field The invention relates to an adhesive, an adhesive permanent magnet and a preparation method thereof. Background The bonded permanent magnet has the advantages of large shape freedom, high dimensional accuracy, no need of secondary processing, flexible magnetizing mode and the like, and is widely applied to the fields of new energy automobiles, household appliances, consumer electronics, industrial automation and the like. The existing preparation method of the bonded permanent magnet mainly comprises the steps of mixing permanent magnet alloy magnetic powder and thermosetting epoxy resin binders to form a premix, pressing and forming, and then placing a green body into a baking oven at 150-180 ℃ for curing treatment, wherein the curing time is regulated according to the specification of the product, and is usually 15-120 min. The existing preparation method has longer production period and larger energy consumption. The magnetic powder is easy to oxidize in a long-time high-temperature environment, and has adverse effects on magnetic performance, subsequent surface treatment and other procedures, and particularly for permanent magnet products with thin walls and large length-diameter ratio, the magnetic powder is easy to deform at high temperature and has difficult control of dimensional tolerance. Therefore, how to shorten the high-temperature curing time and simultaneously ensure the dimensional accuracy, the deformation resistance and the magnetic performance of the bonded permanent magnet becomes a problem to be solved in the art. CN102969116a discloses a UV cured bonded magnet. The raw material formula of the UV cured bonded magnet comprises, by mass, 90-98.5% of bonded NdFeB magnetic powder, sr ferrite magnetic powder or Ba ferrite magnetic powder, 1-8% of a UV cured resin mixture, 0.1-1% of a coupling agent and 0.05-0.4% of a stearate lubricant. The UV curing bonding magnet can be rapidly cured under ultraviolet irradiation, but the curing degree is lower because the internal adhesive of the magnet is difficult to be irradiated by ultraviolet, the crushing strength of the magnet is required to be improved, and the deformation resistance is not ideal. CN109712798a discloses a method for preparing bonded neodymium-iron-boron magnet by 3D printing. According to the method, liquid photosensitive resin is adopted to prepare printing slurry of neodymium iron boron, printing of high-solid-content slurry is realized through an ultrasonic vibration control system, so that the formability of the slurry, the precision and the high density of a printed magnet are ensured, the printing orientation molding of the magnet is selectively realized through an orientation magnetizing system, and finally, the high-performance bonded neodymium iron boron part with a complex shape is obtained. The liquid photosensitive resin is adopted to prepare the 3D printed neodymium iron boron slurry, so that the photocuring rapid forming is realized. The method requires a 3D printing device with an ultrasonic vibration and orientation magnetizing system, cannot be realized in existing industrial equipment, and is too high in preparation cost. In addition, the method does not disclose the magnetic properties and deformation resistance of the bonded NdFeB magnet. Disclosure of Invention In view of the above, an object of the present invention is to provide an adhesive, by which a bonded permanent magnet can be rapidly cured and which has high dimensional accuracy, excellent deformation resistance and good magnetic properties. Another object of the present invention is to provide a method for preparing the above binder. It is a further object of the present invention to provide the use of the above-described adhesive. It is yet another object of the present invention to provide a bonded permanent magnet. Still another object of the present invention is to provide a method for manufacturing the bonded permanent magnet described above. The invention adopts the following technical scheme to realize the aim. In one aspect, the invention provides a binder which is prepared from the following raw materials in parts by weight: 35-60 parts by weight of a first curing resin, 10-40 parts by weight of a second curing resin, 2-5 parts by weight of a photoinitiator, 0.1-0.5 part by weight of a photosensitizer, 2-8 parts by weight of a nitrogen-containing organic curing agent, 5-20 parts by weight of a reactive diluent, 0.1-0.5 part by weight of a defoaming agent, 0.02-0.1 part by weight of a polymerization inhibitor and 0.2-0.5 part by weight of an antioxidant; The first curing resin consists of at least one of epoxy acrylate resin and phenolic epoxy acrylate resin according to a weight ratio of 2-3:1, wherein the resin A is at least one of polyurethane acrylate resin and polyether acrylate resin, the second curing resin is at least one of bisphenol A epoxy resin and cy