Hot-pressing magnetic powder connecting adhesive and preparation method thereof

Abstract

The invention discloses hot-pressing magnetic powder connecting glue and a preparation method thereof, and belongs to the technical field of connecting glue, the hot-pressing magnetic powder connecting glue comprises the following components by weight: 45-65% of fluorine-containing modified epoxy resin, 15-20% of a curing agent, 20-30% of a filler, 5-8% of a flexibilizer, and 0.5-1.5% of an auxiliary agent; the fluorine-containing modified epoxy resin is obtained through a reaction of bisphenol A type epoxy resin and perfluorooctyltriethoxysilane, and the mass ratio of the bisphenol A type epoxy resin to the perfluorooctyltriethoxysilane is (8-5): 1. The hot-pressing magnetic powder connecting adhesive has extremely high Tg and Td, can stably work at 280 DEG C for a long time, is obviously superior to existing products (such as DM-6997), and meets the requirements of magnetic powder connection and insulation in high-temperature scenes such as oil drilling and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of connection adhesives, and particularly relates to a hot-pressing magnetic powder connection adhesive and a preparation method thereof. Background Art

[0002] The manufacture of integrally formed piezoelectric inductors relies on a hot-pressing magnetic powder connection adhesive to insulate and coat magnetic powder particles and assemble them with coils for hot pressing. Taking the conventional DM-6997 adhesive on the market as an example, DM-6997 is a two-component epoxy resin-based adhesive (component A is a transparent epoxy resin solution, and component B is an off-white curing agent), which has excellent insulation and adhesiveness. The mixing mass ratio is 30:1, and the curing condition is 1 hour at 150°C. Its main properties include: glass transition temperature (Tg) 110°C, cracking temperature (Td, 5% weight loss) 275°C, and tensile shear strength greater than 8.0 MPa. However, the Tg of this adhesive is relatively low (110°C), and the long-term working temperature is limited to below 125°C, which cannot meet the requirements of extreme high-temperature environments such as oil drilling (220 - 260°C or even higher). In addition, its reliability test only covers the range of -55 to 125°C, and the stability has not been verified at higher temperatures.

[0003] With the increasing requirements of special industries for the temperature resistance performance of inductors, the existing hot-pressing magnetic powder connection insulating adhesives are prone to cracking or splitting at high temperatures, resulting in the failure of inductors.

[0004] In view of this, this application is proposed. Summary of the Invention

[0005] The purpose of the present invention is to overcome the deficiencies of the existing technology and provide a hot-pressing magnetic powder connection adhesive and a preparation method thereof. The hot-pressing magnetic powder connection adhesive of the present invention has extremely high Tg and Td, can work stably at 280°C for a long time, is significantly superior to existing products (such as DM-6997), and meets the magnetic powder connection and insulation requirements in high-temperature scenarios such as oil drilling.

[0006] To achieve the above purpose, the technical solution adopted by the present invention is as follows: A hot-pressing magnetic powder connection adhesive, comprising the following components in weight percentage: 45 - 65% fluorine-modified epoxy resin, 15 - 20% curing agent, 20 - 30% filler, 5 - 8% toughening agent, 0.5 - 1.5% auxiliary agent; The fluorine-modified epoxy resin is obtained by reacting bisphenol A epoxy resin with perfluorooctyltriethoxysilane, and the mass ratio of bisphenol A epoxy resin to perfluorooctyltriethoxysilane is (8 - 5):1 The curing agent comprises 4,4'-diaminodiphenyl sulfone and cashew shell oil phenolic amine with a mass ratio of 1:(0.5 - 2); The filler includes wollastonite fiber and flaky carbonyl iron powder with a mass ratio of 1:(0.5 - 2).

[0007] As a preferred embodiment of the present invention, the viscosity of the cashew shell oil phenolic amine at 25°C is 2300 - 2500 cPs, and the amine value is 340 - 390 mgKOH / g.

[0008] As a preferred embodiment of the present invention, the aspect ratio of the flaky carbonyl iron powder is (8 - 10):1.

[0009] As a preferred embodiment of the present invention, the aspect ratio of the wollastonite fiber is (12 - 15):1.

[0010] As a preferred embodiment of the present invention, the epoxy equivalent of the bisphenol A epoxy resin is 625 - 675 g / eq.

[0011] As a preferred embodiment of the present invention, the preparation method of the fluorine-containing modified epoxy resin is: mixing bisphenol A epoxy resin and perfluorooctyltriethoxysilane uniformly, adding a catalyst, and reacting to obtain the fluorine-containing modified epoxy resin.

[0012] As a preferred embodiment of the present invention, the catalyst is tetrabutyl titanate, and the mass ratio of the bisphenol A epoxy resin to the catalyst is 100:(0.1 - 1); The temperature of the reaction is 75 - 95°C, and the reaction time is 2 - 8 h.

[0013] As a preferred embodiment of the present invention, the toughening agent is polyetheramine.

[0014] As a preferred embodiment of the present invention, the auxiliary agent includes at least one of a defoaming agent and a leveling agent.

[0015] The present invention also provides a preparation method of a hot-pressed magnetic powder connecting adhesive, comprising the following steps: Mixing the fluorine-containing modified epoxy resin, curing agent, filler, toughening agent, and auxiliary agent uniformly to obtain the hot-pressed magnetic powder connecting adhesive.

[0016] The beneficial effects of the present invention are as follows: (1) By using the fluorine-modified epoxy resin obtained by reacting bisphenol A epoxy resin with perfluorooctyltriethoxysilane as the main resin, the thermal stability and chemical resistance of the fluorine-modified epoxy resin are significantly improved. (2) By optimizing bisphenol A epoxy resin and curing agent, the crosslinking density and thermal stability are further improved, so that the hot-pressed magnetic powder connecting adhesive has extremely high Tg and Td, can work stably at 280 °C for a long time, is significantly superior to existing products (such as DM-6997), and meets the magnetic powder connection and insulation requirements in high-temperature scenarios such as oil drilling; (3) Wollastonite fiber and flaky carbonyl iron powder with a mass ratio of 1: (0.5~2) are used as fillers. The wollastonite fiber and flaky carbonyl iron powder are interlaced with each other, can form a dense filling network structure in the system, and have certain magnetism, restrict the movement of polymer segments, effectively improve the thermal stability of the system, effectively improve Tg and Td, and improve the bonding performance. Detailed Embodiments

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below. Apparently, the described embodiments are some, but not all, of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0018] In the present application, among the technically characterized descriptions in an open-ended manner, it includes a closed technical solution composed of the listed features, and also includes an open technical solution containing the listed features.

[0019] In the present application, regarding the numerical range, unless otherwise specified, the above numerical range is considered continuous, and includes the minimum and maximum values of this range, as well as each value between such minimum and maximum values. Further, when the range refers to an integer, it includes each integer between the minimum and maximum values of this range. In addition, when multiple ranges are provided to describe features or characteristics, these ranges can be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all sub-ranges subsumed therein.

[0020] In the present application, there is no particular limitation on the specific dispersion and stirring treatment methods.

[0021] Unless otherwise specified, the component raw materials or instruments used in the embodiments and comparative examples of the present invention are all commercially available raw materials or instruments, and the component raw materials used in each parallel experiment are the same.

[0022] Among them, the raw materials of the examples and comparative examples are as follows: Bisphenol A epoxy resin - 1: Epoxy equivalent is 625 - 675 g / eq, Shanghai Kayin Chemical Industry, product number epoxy resin KD - 242GHF.

[0023] Bisphenol A epoxy resin - 2: Epoxy equivalent is 875 - 975 g / eq, Shanghai Kayin Chemical Industry, product number epoxy resin KD - 214C.

[0024] Bisphenol A epoxy resin - 3, Epoxy equivalent is 405 - 450 g / eq, Shanghai Kayin Chemical Industry, product number epoxy resin KD - 211SW.

[0025] Cardanol novolac amine - 1: Viscosity at 25°C is 2500 cPs, amine value is 390 mgKOH / g. Cardolite, product number NX - 5352.

[0026] Cardanol novolac amine - 2: Viscosity at 25°C is 2300 cPs, amine value is 340 mgKOH / g. Cardolite, product number NX - 541LV.

[0027] Cardanol novolac amine - 3: Viscosity at 25°C is 770 cPs, amine value is 561 mgKOH / g. Cardolite, product number NX - 5567.

[0028] Cardanol novolac amine - 4: Viscosity at 25°C is 25000 cPs, amine value is 130 mgKOH / g. Cardolite, product number NC - 641.

[0029] Flaky carbonyl iron powder - 1: Aspect ratio (thickness to diameter) is 10:1, Xinxiang Sanyi New Materials, product number PF - 01.

[0030] Flaky carbonyl iron powder - 2: Aspect ratio (thickness to diameter) is 8:1, Xinxiang Sanyi New Materials, product number PF - 02.

[0031] Flaky carbonyl iron powder - 3: Aspect ratio (thickness to diameter) is 20:1, Xinxiang Sanyi New Materials, product number PF - 04.

[0032] Flaky carbonyl iron powder - 4: Aspect ratio (thickness to diameter) is 5:1, Xinxiang Sanyi New Materials, product number PF - 03.

[0033] Wollastonite fiber - 1: Aspect ratio (length to diameter) is 12:1, Fengjiashan Wollastonite Fiber Co., Ltd., product number WFA50.

[0034] Wollastonite fiber - 2: Aspect ratio (length to diameter) is 15:1, Fengjiashan Wollastonite Fiber Co., Ltd., product number WFA60.

[0035] Wollastonite fiber - 3: Aspect ratio (length to diameter) is 20:1, Fengjiashan Wollastonite Fiber Co., Ltd., product number WFA80.

[0036] Wollastonite fiber - 4: Aspect ratio 9:1, Fengjiashan Silicon Fiber Co., Ltd., grade WFB5.

[0037] Polyetheramine: Macklin reagent, D - 230.

[0038] Defoamer: BYK028 from BYK.

[0039] The following examples are provided to facilitate the understanding of the present invention. These examples are not provided to limit the scope of the claims.

[0040] Example 1 A hot - press magnetic powder connecting adhesive, comprising the following components by weight percentage: 51% fluorine - modified epoxy resin, 18% curing agent, 24% filler, 6% polyetheramine, 1% defoamer.

[0041] The filler includes wollastonite fiber - 1 and flaky carbonyl iron powder - 1 with a mass ratio of 1:0.5.

[0042] The preparation method of the fluorine - modified epoxy resin is as follows: Mix 100 g of bisphenol A epoxy resin - 1 and 15 g of perfluorooctyltriethoxysilane evenly, add 0.5 g of tetrabutyl titanate, and stir - react at 90 °C for 5 hours to obtain the fluorine - modified epoxy resin.

[0043] The curing agent includes 4,4’ - diaminodiphenyl sulfone and cashew shell oil phenolic amine - 1 with a mass ratio of 1:2.

[0044] The preparation method of the hot - press magnetic powder connecting adhesive includes the following steps: Mix the fluorine - modified epoxy resin, curing agent, filler, polyetheramine, and defoamer evenly to obtain the hot - press magnetic powder connecting adhesive.

[0045] Example 2 A hot - press magnetic powder connecting adhesive, comprising the following components by weight percentage: 48.5% fluorine - modified epoxy resin, 15% curing agent, 28% filler, 8% polyetheramine, 0.5% defoamer.

[0046] The filler includes wollastonite fiber - 1 and flaky carbonyl iron powder - 1 with a mass ratio of 1:0.5.

[0047] The preparation method of the fluorine - modified epoxy resin is as follows: Mix 100 g of bisphenol A epoxy resin - 1 and 15 g of perfluorooctyltriethoxysilane evenly, add 0.5 g of tetrabutyl titanate, and stir - react at 90 °C for 5 hours to obtain the fluorine - modified epoxy resin.

[0048] The curing agent includes 4,4’ - diaminodiphenyl sulfone and cashew shell oil phenolic amine - 1 with a mass ratio of 1:2.

[0049] The preparation method of the hot-pressing magnetic powder connecting adhesive comprises the following steps: Mix the fluorine-modified epoxy resin, curing agent, filler, polyetheramine and defoamer evenly to obtain the hot-pressing magnetic powder connecting adhesive.

[0050] Example 3 A hot-pressing magnetic powder connecting adhesive comprises the following components in percentage by weight: 51% fluorine-modified epoxy resin, 18% curing agent, 24% filler, 6% polyetheramine and 1% defoamer.

[0051] The filler comprises wollastonite fiber-1 and flaky carbonyl iron powder-1 with a mass ratio of 1:0.5.

[0052] The preparation method of the fluorine-modified epoxy resin is as follows: Mix 100 g of bisphenol A epoxy resin-2 and 15 g of perfluorooctyltriethoxysilane evenly, add 0.5 g of tetrabutyl titanate, and stir and react at 90 °C for 5 hours to obtain the fluorine-modified epoxy resin.

[0053] The curing agent comprises 4,4'-diaminodiphenyl sulfone and cashew shell oil phenolic amine-1 with a mass ratio of 1:2.

[0054] The preparation method of the hot-pressing magnetic powder connecting adhesive comprises the following steps: Mix the fluorine-modified epoxy resin, curing agent, filler, polyetheramine and defoamer evenly to obtain the hot-pressing magnetic powder connecting adhesive.

[0055] Example 4 A hot-pressing magnetic powder connecting adhesive comprises the following components in percentage by weight: 51% fluorine-modified epoxy resin, 18% curing agent, 24% filler, 6% polyetheramine and 1% defoamer.

[0056] The filler comprises wollastonite fiber-1 and flaky carbonyl iron powder-1 with a mass ratio of 1:0.5.

[0057] The preparation method of the fluorine-modified epoxy resin is as follows: Mix 100 g of bisphenol A epoxy resin-3 and 15 g of perfluorooctyltriethoxysilane evenly, add 0.5 g of tetrabutyl titanate, and stir and react at 90 °C for 5 hours to obtain the fluorine-modified epoxy resin.

[0058] The curing agent comprises 4,4'-diaminodiphenyl sulfone and cashew shell oil phenolic amine-1 with a mass ratio of 1:2.

[0059] The preparation method of the hot-pressing magnetic powder connecting adhesive comprises the following steps: Mix the fluorine-modified epoxy resin, curing agent, filler, polyetheramine and defoamer evenly to obtain the hot-pressing magnetic powder connecting adhesive.

[0060] Example 5 A hot-pressing magnetic powder connecting adhesive, comprising components in the following weight percentages: 51% fluorine-modified epoxy resin, 18% curing agent, 24% filler, 6% polyetheramine, and 1% defoaming agent.

[0061] The filler includes wollastonite fiber-1 and flaky carbonyl iron powder-1 with a mass ratio of 1:2.

[0062] The preparation method of the fluorine-modified epoxy resin is as follows: Mix 100 g of bisphenol A epoxy resin-1 and 15 g of perfluorooctyltriethoxysilane evenly, add 0.5 g of tetrabutyl titanate, and stir and react at 90 °C for 5 hours to obtain the fluorine-modified epoxy resin.

[0063] The curing agent includes 4,4'-diaminodiphenyl sulfone and cashew shell oil phenolic amine-1 with a mass ratio of 1:0.5.

[0064] The preparation method of the hot-pressing magnetic powder connecting adhesive includes the following steps: Mix the fluorine-modified epoxy resin, curing agent, filler, polyetheramine, and defoaming agent evenly to obtain the hot-pressing magnetic powder connecting adhesive.

[0065] Example 6 A hot-pressing magnetic powder connecting adhesive, comprising components in the following weight percentages: 51% fluorine-modified epoxy resin, 18% curing agent, 24% filler, 6% polyetheramine, and 1% defoaming agent.

[0066] The filler includes wollastonite fiber-1 and flaky carbonyl iron powder-1 with a mass ratio of 1:0.5.

[0067] The preparation method of the fluorine-modified epoxy resin is as follows: Mix 100 g of bisphenol A epoxy resin-1 and 15 g of perfluorooctyltriethoxysilane evenly, add 0.5 g of tetrabutyl titanate, and stir and react at 90 °C for 5 hours to obtain the fluorine-modified epoxy resin.

[0068] The curing agent includes 4,4'-diaminodiphenyl sulfone and cashew shell oil phenolic amine-2 with a mass ratio of 1:2.

[0069] The preparation method of the hot-pressing magnetic powder connecting adhesive includes the following steps: Mix the fluorine-modified epoxy resin, curing agent, filler, polyetheramine, and defoaming agent evenly to obtain the hot-pressing magnetic powder connecting adhesive.

[0070] Example 7 A hot-pressing magnetic powder connecting adhesive, comprising components in the following weight percentages: 51% fluorine-modified epoxy resin, 18% curing agent, 24% filler, 6% polyetheramine, and 1% defoaming agent.

[0071] The filler includes wollastonite fiber-1 and flaky carbonyl iron powder-1 with a mass ratio of 1:0.5.

[0072] The preparation method of the fluorine-containing modified epoxy resin is as follows: 100 g of bisphenol A epoxy resin-1 and 15 g of perfluorooctyltriethoxysilane are mixed evenly, 0.5 g of tetrabutyl titanate is added, and the mixture is stirred and reacted at 90 °C for 5 hours to obtain the fluorine-containing modified epoxy resin.

[0073] The curing agent includes 4,4'-diaminodiphenyl sulfone and cashew shell oil phenolic amine-3 with a mass ratio of 1:2.

[0074] The preparation method of the hot-pressed magnetic powder connecting adhesive includes the following steps: The fluorine-containing modified epoxy resin, curing agent, filler, polyetheramine, and defoaming agent are mixed evenly to obtain the hot-pressed magnetic powder connecting adhesive.

[0075] Example 8 A hot-pressed magnetic powder connecting adhesive includes the following components by weight percentage: 51% fluorine-containing modified epoxy resin, 18% curing agent, 24% filler, 6% polyetheramine, and 1% defoaming agent.

[0076] The filler includes wollastonite fiber-1 and flaky carbonyl iron powder-1 with a mass ratio of 1:0.5.

[0077] The preparation method of the fluorine-containing modified epoxy resin is as follows: 100 g of bisphenol A epoxy resin-1 and 15 g of perfluorooctyltriethoxysilane are mixed evenly, 0.5 g of tetrabutyl titanate is added, and the mixture is stirred and reacted at 90 °C for 5 hours to obtain the fluorine-containing modified epoxy resin.

[0078] The curing agent includes 4,4'-diaminodiphenyl sulfone and cashew shell oil phenolic amine-4 with a mass ratio of 1:2.

[0079] The preparation method of the hot-pressed magnetic powder connecting adhesive includes the following steps: The fluorine-containing modified epoxy resin, curing agent, filler, polyetheramine, and defoaming agent are mixed evenly to obtain the hot-pressed magnetic powder connecting adhesive.

[0080] Example 9 A hot-pressed magnetic powder connecting adhesive includes the following components by weight percentage: 51% fluorine-containing modified epoxy resin, 18% curing agent, 24% filler, 6% polyetheramine, and 1% defoaming agent.

[0081] The filler includes wollastonite fiber-2 and flaky carbonyl iron powder-1 with a mass ratio of 1:0.5.

[0082] The preparation method of the fluorine-modified epoxy resin is as follows: 100 g of bisphenol A epoxy resin-1 and 15 g of perfluorooctyltriethoxysilane are mixed evenly, 0.5 g of tetrabutyl titanate is added, and the mixture is stirred and reacted at 90 °C for 5 hours to obtain the fluorine-modified epoxy resin.

[0083] The curing agent includes 4,4'-diaminodiphenyl sulfone and cashew shell oil phenolic amine-1 with a mass ratio of 1:2.

[0084] The preparation method of the hot pressing magnetic powder connecting adhesive includes the following steps: The fluorine-modified epoxy resin, the curing agent, the filler, the polyetheramine, and the defoaming agent are mixed evenly to obtain the hot pressing magnetic powder connecting adhesive.

[0085] Example 10 A hot pressing magnetic powder connecting adhesive includes the following components in weight percentage: 51% of fluorine-modified epoxy resin, 18% of curing agent, 24% of filler, 6% of polyetheramine, and 1% of defoaming agent.

[0086] The filler includes wollastonite fiber-3 and flaky carbonyl iron powder-1 with a mass ratio of 1:0.5.

[0087] The preparation method of the fluorine-modified epoxy resin is as follows: 100 g of bisphenol A epoxy resin-1 and 15 g of perfluorooctyltriethoxysilane are mixed evenly, 0.5 g of tetrabutyl titanate is added, and the mixture is stirred and reacted at 90 °C for 5 hours to obtain the fluorine-modified epoxy resin.

[0088] The curing agent includes 4,4'-diaminodiphenyl sulfone and cashew shell oil phenolic amine-1 with a mass ratio of 1:2.

[0089] The preparation method of the hot pressing magnetic powder connecting adhesive includes the following steps: The fluorine-modified epoxy resin, the curing agent, the filler, the polyetheramine, and the defoaming agent are mixed evenly to obtain the hot pressing magnetic powder connecting adhesive.

[0090] Example 11 A hot pressing magnetic powder connecting adhesive includes the following components in weight percentage: 51% of fluorine-modified epoxy resin, 18% of curing agent, 24% of filler, 6% of polyetheramine, and 1% of defoaming agent.

[0091] The filler includes wollastonite fiber-4 and flaky carbonyl iron powder-1 with a mass ratio of 1:0.5.

[0092] The preparation method of the fluorine-modified epoxy resin is as follows: 100 g of bisphenol A epoxy resin-1 and 15 g of perfluorooctyltriethoxysilane are mixed evenly, 0.5 g of tetrabutyl titanate is added, and the mixture is stirred and reacted at 90 °C for 5 hours to obtain the fluorine-modified epoxy resin.

[0093] The curing agent includes 4,4'-diaminodiphenyl sulfone and cardanol phenolic aldehyde amine-1 with a mass ratio of 1:2.

[0094] The preparation method of the hot pressing magnetic powder connecting adhesive includes the following steps: Mix the fluorine-containing modified epoxy resin, curing agent, filler, polyether amine, and defoaming agent evenly to obtain the hot pressing magnetic powder connecting adhesive.

[0095] Example 12 A hot pressing magnetic powder connecting adhesive includes the following components in weight percentage: 51% fluorine-containing modified epoxy resin, 18% curing agent, 24% filler, 6% polyether amine, and 1% defoaming agent.

[0096] The filler includes wollastonite fiber-1 and flaky carbonyl iron powder-2 with a mass ratio of 1:0.5.

[0097] The preparation method of the fluorine-containing modified epoxy resin is as follows: Mix 100 g of bisphenol A epoxy resin-1 and 15 g of perfluorooctyltriethoxysilane evenly, add 0.5 g of tetrabutyl titanate, and stir and react at 90 °C for 5 hours to obtain the fluorine-containing modified epoxy resin.

[0098] The curing agent includes 4,4'-diaminodiphenyl sulfone and cardanol phenolic aldehyde amine-1 with a mass ratio of 1:2.

[0099] The preparation method of the hot pressing magnetic powder connecting adhesive includes the following steps: Mix the fluorine-containing modified epoxy resin, curing agent, filler, polyether amine, and defoaming agent evenly to obtain the hot pressing magnetic powder connecting adhesive.

[0100] Example 13 A hot pressing magnetic powder connecting adhesive includes the following components in weight percentage: 51% fluorine-containing modified epoxy resin, 18% curing agent, 24% filler, 6% polyether amine, and 1% defoaming agent.

[0101] The filler includes wollastonite fiber-1 and flaky carbonyl iron powder-3 with a mass ratio of 1:0.5.

[0102] The preparation method of the fluorine-containing modified epoxy resin is as follows: Mix 100 g of bisphenol A epoxy resin-1 and 15 g of perfluorooctyltriethoxysilane evenly, add 0.5 g of tetrabutyl titanate, and stir and react at 90 °C for 5 hours to obtain the fluorine-containing modified epoxy resin.

[0103] The curing agent includes 4,4'-diaminodiphenyl sulfone and cardanol phenolic aldehyde amine-1 with a mass ratio of 1:2.

[0104] The preparation method of the hot pressing magnetic powder connecting adhesive includes the following steps: Mix the fluorine-modified epoxy resin, curing agent, filler, polyetheramine, and defoamer evenly to obtain the hot-pressing magnetic powder connecting adhesive.

[0105] Example 14 A hot-pressing magnetic powder connecting adhesive, comprising the following components in weight percentages: 51% fluorine-modified epoxy resin, 18% curing agent, 24% filler, 6% polyetheramine, and 1% defoamer.

[0106] The filler includes wollastonite fiber-1 and flaky carbonyl iron powder-4 with a mass ratio of 1:0.5.

[0107] The preparation method of the fluorine-modified epoxy resin is as follows: Mix 100 g of bisphenol A epoxy resin-1 and 15 g of perfluorooctyltriethoxysilane evenly, add 0.5 g of tetrabutyl titanate, and stir and react at 90 °C for 5 hours to obtain the fluorine-modified epoxy resin.

[0108] The curing agent includes 4,4'-diaminodiphenyl sulfone and cashew shell oil phenolic amine-1 with a mass ratio of 1:2.

[0109] The preparation method of the hot-pressing magnetic powder connecting adhesive includes the following steps: Mix the fluorine-modified epoxy resin, curing agent, filler, polyetheramine, and defoamer evenly to obtain the hot-pressing magnetic powder connecting adhesive.

[0110] Comparative Example 1 A hot-pressing magnetic powder connecting adhesive, comprising the following components in weight percentages: 51% bisphenol A epoxy resin-1, 18% curing agent, 24% filler, 6% polyetheramine, and 1% defoamer.

[0111] The filler includes wollastonite fiber-1 and flaky carbonyl iron powder-1 with a mass ratio of 1:0.5.

[0112] The curing agent includes 4,4'-diaminodiphenyl sulfone and cashew shell oil phenolic amine-1 with a mass ratio of 1:2.

[0113] The preparation method of the hot-pressing magnetic powder connecting adhesive includes the following steps: Mix bisphenol A epoxy resin-1, curing agent, filler, polyetheramine, and defoamer evenly to obtain the hot-pressing magnetic powder connecting adhesive.

[0114] Comparative Example 2 A hot-pressing magnetic powder connecting adhesive, comprising the following components in weight percentages: 51% fluorine-modified epoxy resin, 18% curing agent, 24% filler, 6% polyetheramine, and 1% defoamer.

[0115] The filler includes wollastonite fiber-1 and flaky carbonyl iron powder-1 with a mass ratio of 1:0.5.

[0116] The preparation method of the fluorine-modified epoxy resin is as follows: 100 g of bisphenol A epoxy resin-1 and 15 g of perfluorooctyltriethoxysilane are mixed evenly, 0.5 g of tetrabutyl titanate is added, and the mixture is stirred and reacted at 90 °C for 5 hours to obtain the fluorine-modified epoxy resin.

[0117] The curing agent is 4,4'-diaminodiphenyl sulfone.

[0118] The preparation method of the hot-pressing magnetic powder connecting adhesive includes the following steps: The fluorine-modified epoxy resin, the curing agent, the filler, the polyetheramine, and the defoaming agent are mixed evenly to obtain the hot-pressing magnetic powder connecting adhesive.

[0119] Comparative Example 3 A hot-pressing magnetic powder connecting adhesive includes the following components in weight percentage: 51% of fluorine-modified epoxy resin, 18% of curing agent, 24% of filler, 6% of polyetheramine, and 1% of defoaming agent.

[0120] The filler includes wollastonite fiber-1 and flaky carbonyl iron powder-1 with a mass ratio of 1:0.5.

[0121] The preparation method of the fluorine-modified epoxy resin is as follows: 100 g of bisphenol A epoxy resin-1 and 15 g of perfluorooctyltriethoxysilane are mixed evenly, 0.5 g of tetrabutyl titanate is added, and the mixture is stirred and reacted at 90 °C for 5 hours to obtain the fluorine-modified epoxy resin.

[0122] The curing agent is cashew shell oil phenolic amine-1.

[0123] The preparation method of the hot-pressing magnetic powder connecting adhesive includes the following steps: The fluorine-modified epoxy resin, the curing agent, the filler, the polyetheramine, and the defoaming agent are mixed evenly to obtain the hot-pressing magnetic powder connecting adhesive.

[0124] Comparative Example 4 A hot-pressing magnetic powder connecting adhesive includes the following components in weight percentage: 51% of fluorine-modified epoxy resin, 18% of curing agent, 25% of filler, 6% of polyetheramine, and 1% of defoaming agent.

[0125] The filler includes wollastonite fiber-1 and flaky carbonyl iron powder-1 with a mass ratio of 1:0.5.

[0126] The preparation method of the fluorine-modified epoxy resin is as follows: 100 g of bisphenol A epoxy resin-1 and 15 g of perfluorooctyltriethoxysilane are mixed evenly, 0.5 g of tetrabutyl titanate is added, and the mixture is stirred and reacted at 90 °C for 5 hours to obtain the fluorine-modified epoxy resin.

[0127] The curing agent includes 4,4'-diaminodiphenyl sulfone and cardanol phenolic aldehyde amine-1 with a mass ratio of 1:0.25.

[0128] The preparation method of the hot-pressing magnetic powder connecting adhesive includes the following steps: Mix the fluorine-containing modified epoxy resin, curing agent, filler, polyetheramine, and defoaming agent evenly to obtain the hot-pressing magnetic powder connecting adhesive.

[0129] Comparative Example 5 A hot-pressing magnetic powder connecting adhesive includes the following components in weight percentages: 51% fluorine-containing modified epoxy resin, 18% curing agent, 24% filler, 6% polyetheramine, and 1% defoaming agent.

[0130] The filler includes wollastonite fiber-1 and flaky carbonyl iron powder-1 with a mass ratio of 1:0.5.

[0131] The preparation method of the fluorine-containing modified epoxy resin is as follows: Mix 100 g of bisphenol A epoxy resin-1 and 15 g of perfluorooctyltriethoxysilane evenly, add 0.5 g of tetrabutyl titanate, and stir and react at 90 °C for 5 hours to obtain the fluorine-containing modified epoxy resin.

[0132] The curing agent includes 4,4'-diaminodiphenyl sulfone and cardanol phenolic aldehyde amine-1 with a mass ratio of 1:4.

[0133] The preparation method of the hot-pressing magnetic powder connecting adhesive includes the following steps: Mix the fluorine-containing modified epoxy resin, curing agent, filler, polyetheramine, and defoaming agent evenly to obtain the hot-pressing magnetic powder connecting adhesive.

[0134] Comparative Example 6 A hot-pressing magnetic powder connecting adhesive includes the following components in weight percentages: 51% fluorine-containing modified epoxy resin, 18% curing agent, 24% filler, 6% polyetheramine, and 1% defoaming agent.

[0135] The filler includes wollastonite fiber-1.

[0136] The preparation method of the fluorine-containing modified epoxy resin is as follows: Mix 100 g of bisphenol A epoxy resin-1 and 15 g of perfluorooctyltriethoxysilane evenly, add 0.5 g of tetrabutyl titanate, and stir and react at 90 °C for 5 hours to obtain the fluorine-containing modified epoxy resin.

[0137] The curing agent includes 4,4'-diaminodiphenyl sulfone and cardanol phenolic aldehyde amine-1 with a mass ratio of 1:2.

[0138] The preparation method of the hot-pressing magnetic powder connecting adhesive includes the following steps: Mix the fluorine-modified epoxy resin, curing agent, alumina, polyetheramine, and defoamer evenly to obtain the hot-pressing magnetic powder connecting adhesive described above.

[0139] Comparative Example 7 A hot-pressing magnetic powder connecting adhesive, comprising the following components in weight percentages: 51% fluorine-modified epoxy resin, 18% curing agent, 24% filler, 6% polyetheramine, 1% defoamer.

[0140] The filler includes flaky carbonyl iron powder-1.

[0141] The preparation method of the fluorine-modified epoxy resin is as follows: Mix 100 g of bisphenol A epoxy resin-1 and 15 g of perfluorooctyltriethoxysilane evenly, add 0.5 g of tetrabutyl titanate, and stir and react at 90 °C for 5 hours to obtain the fluorine-modified epoxy resin.

[0142] The curing agent includes 4,4'-diaminodiphenyl sulfone and cashew shell oil phenolic amine-1 with a mass ratio of 1:2.

[0143] The preparation method of the hot-pressing magnetic powder connecting adhesive includes the following steps: Mix the fluorine-modified epoxy resin, curing agent, alumina, polyetheramine, and defoamer evenly to obtain the hot-pressing magnetic powder connecting adhesive described above.

[0144] Test Example 1. Use the DSC method to test Tg and the TGA method to test Td.

[0145] 2. After placing the connecting adhesives of the examples and comparative examples at 200 °C for 1000 h respectively, test the shear strength.

[0146] Table 1 As can be seen from Table 1, the hot-pressing magnetic powder connecting adhesive described in the present invention has extremely high Tg and Td, can work stably at 280 °C for a long time, is significantly superior to existing products (such as DM-6997), and meets the magnetic powder connection and insulation requirements in high-temperature scenarios such as oil drilling.

[0147] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A hot-pressed magnetic powder connecting adhesive, characterized in that, It comprises components in the following weight percentages: 45 - 65% fluorine - modified epoxy resin, 15 - 20% curing agent, 20 - 30% filler, 5 - 8% toughening agent, 0.5 - 1.5% additive; The fluorine - modified epoxy resin is obtained by reacting bisphenol A epoxy resin with perfluorooctyltriethoxysilane, and the mass ratio of bisphenol A epoxy resin to perfluorooctyltriethoxysilane is (8 - 5):1; The curing agent comprises 4,4'-diaminodiphenyl sulfone and cardanol - aldehyde amine with a mass ratio of 1:(0.5 - 2); The filler comprises wollastonite fiber and flaky carbonyl iron powder with a mass ratio of 1:(0.5 - 2).

2. The hot-pressing magnetic powder connecting adhesive according to claim 1, wherein The viscosity of the cardanol - aldehyde amine at 25 °C is 2300 - 2500 cPs, and the amine value is 340 - 390 mgKOH / g.

3. The hot-pressing magnetic powder connecting glue according to claim 1, wherein The thickness - diameter ratio of the flaky carbonyl iron powder is (8 - 10):

1.

4. The hot-pressing magnetic powder connecting adhesive according to claim 1, wherein The length - diameter ratio of the wollastonite fiber is (12 - 15):

1.

5. The hot-pressing magnetic powder connecting glue according to claim 1, characterized in that The epoxy equivalent of the bisphenol A epoxy resin is 625 - 675 g / eq.

6. The hot-pressing magnetic powder connecting glue according to claim 1, characterized in that, The preparation method of the fluorine - modified epoxy resin is: mixing bisphenol A epoxy resin and perfluorooctyltriethoxysilane evenly, adding a catalyst, and reacting to obtain the fluorine - modified epoxy resin.

7. The hot-pressing magnetic powder connecting adhesive according to claim 6, characterized in that The catalyst is tetrabutyl titanate, and the mass ratio of bisphenol A epoxy resin to the catalyst is 100:(0.1 - 1).

8. The hot-pressing magnetic powder connecting adhesive according to claim 6, wherein The temperature of the reaction is 75 - 95 °C, and the reaction time is 2 - 8 h.

9. The hot-pressing magnetic powder connecting adhesive according to claim 1, characterized in that The toughening agent is polyetheramine; the additive comprises at least one of defoamer and leveling agent.

10. The preparation method of the hot-pressed magnetic powder connecting glue according to any one of claims 1 to 9, characterized in that, It comprises the following steps: Mixing the fluorine - modified epoxy resin, curing agent, filler, toughening agent, and additive evenly to obtain the hot - press magnetic powder connecting adhesive.

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