Two-component insulating potting composition and preparation method thereof

Abstract

The invention discloses a bi-component insulating potting composition and a preparation method thereof, and relates to the technical field of electronic component packaging. The bi-component insulating potting composition prepared by the invention is prepared by blending the modified epoxy resin and the hyperbranched epoxy resin, the modified epoxy resin is prepared by adding dihydroxy tetramethyldisiloxane when bisphenol A and epoxy chloropropane are condensed under an alkaline condition, and the hyperbranched epoxy resin is prepared by adding dihydroxy tetramethyldisiloxane when the bisphenol A and the epoxy chloropropane are condensed under the alkaline condition. The dihydroxy tetramethyldisiloxane is prepared by reacting tetramethylsiloxane with methanol, and the hyperbranched epoxy resin is prepared by reacting 1, 1, 3, 3-tetramethyldisiloxane with allyl glycidyl ether and then reacting with vinyl organic silicon resin and modified hydroxybenzene. And the modified hydroxybenzene is prepared by reacting terephthalic acid, 2-hydroxy-1-naphthaldehyde, thionyl chloride and hydrazine hydrate, so that the flame retardance and the heat dissipation property of the potting composition are enhanced.

Description

Technical Field

[0001] The invention relates to the technical field of electronic element packaging, in particular to a two-component insulating potting composition and a preparation method thereof. Background Art

[0002] Potting is the process of mechanically or manually pouring a liquid compound into a device equipped with electronic components and circuits, and solidifying it at room temperature or under heating conditions to become a thermosetting polymer insulating material with excellent performance. The liquid compound used in this process is the potting glue; the potting glue is in a liquid state before it is solidified and has fluidity. The viscosity of the glue varies according to the material, performance, and production process of the product. The potting glue can only realize its use value after it is completely solidified. After solidification, it can play the role of waterproof, moisture-proof, dust-proof, insulating, thermally conductive, confidential, anti-corrosion, temperature-resistant, and shock-proof. There are many types of electronic potting glue. From the type of material, the most common ones are mainly three types, namely epoxy resin potting glue, silicone resin potting glue, and polyurethane potting glue. These three types of potting glue can be subdivided into hundreds of different products.

[0003] With the rapid development of microelectronic integration technology, the assembly density has increased rapidly, the operating frequency of electronic components has increased dramatically, and the heat generated has also increased. Therefore, heat dissipation has become an important factor affecting the service life of electronic components. High thermal conductivity insulating potting composite materials can not only provide a safe and reliable heat dissipation path for electronic components, but also play the role of insulation, shock absorption, moisture resistance and corrosion resistance. The thermal conductive path formed by the thermal conductive filler in the thermal conductive potting composite material greatly affects the thermal conductivity of the composite material. Therefore, the present invention studies and prepares a two-component insulating potting composition to solve the above problems. Summary of the invention

[0004] The object of the present invention is to provide a two-component insulating potting composition and a preparation method thereof, so as to solve the problems raised in the above background technology.

[0005] In order to solve the above technical problems, the present invention provides the following technical solution: a two-component insulating potting composition, wherein the two-component insulating potting composition is prepared by blending a modified epoxy resin and a hyperbranched epoxy resin.

[0006] Preferably, the modified epoxy resin is prepared by adding bishydroxytetramethyldisiloxane to the condensation of bisphenol A and epichlorohydrin under alkaline conditions; the bishydroxytetramethyldisiloxane is prepared by the reaction of tetramethylsiloxane and methanol.

[0007] Preferably, the hyperbranched epoxy resin is prepared by reacting 1,1,3,3-tetramethyldisiloxane with allyl glycidyl ether, and then reacting with vinyl silicone resin and modified hydroxybenzene.

[0008] Preferably, the modified hydroxybenzene is prepared by reacting terephthalic acid, 2-hydroxy-1-naphthaldehyde, thionyl chloride and hydrazine hydrate.

[0009] Preferably, the two-component insulating potting composition and the preparation method thereof include the following specific steps:

[0010] S1. Under an argon atmosphere, tetramethylsiloxane and methanol are mixed in a mass ratio of 1:4 to 8, and after stirring evenly, 0.02 to 0.04 times the mass of tetramethylsiloxane trifluoromethylsulfonic acid is added, the temperature is raised to 63 to 65°C, and after reflux reaction for 8 to 10 hours, atmospheric distillation and pressure distillation are performed in sequence, and the fraction at 220 to 230°C is collected to obtain bishydroxytetramethyldisiloxane;

[0011] S2. Mix bisphenol A, epichlorohydrin and bishydroxytetramethyldisiloxane in a mass ratio of 1:5-8:0.1-0.3, heat and dissolve, add 0.02-0.04 times the mass of bisphenol A as a catalyst benzyltrimethylammonium bromide, heat to 90-100°C, react for 4-6 hours, rotary evaporate, add 2-4 times the mass of bisphenol A and a mass fraction of 8-12% sodium hydroxide solution, cool to 68-72°C, react for 6-8 hours, add 0.1-0.2 times the mass of bisphenol A in methyl isobutyl ketone at a rate of 1-3 ml / min, stir evenly and filter, wash the filtrate with deionized water for 8-10 times, rotary evaporate again, add 0.02-0.06 times the mass of bisphenol A in ethyl acetate, stir evenly and filter again, rotary evaporate, and finally dry to obtain a modified epoxy resin;

[0012] S3. 1,1,3,3,-tetramethyldisiloxane, allyl glycidyl ether and catalyst are heated to 68-72°C in a mass ratio of 20-21:6:6, react for 10-12h, then add 0.3-0.4 times the mass of the catalyst of vinyl silicone resin and 2-3 times the mass of the catalyst of tetrahydrofuran, continue to react for 10-12h, filter and heat to 125-135°C, adjust the vacuum degree to 600-700Pa, and rotary evaporate to obtain a hyperbranched epoxy resin;

[0013] S4. Combine the modified epoxy resin, hyperbranched epoxy resin and triethylamine in a mass ratio of 8-10:1:0.01-0.03, stir evenly and transfer to a mold, heat to 92-96° C., and cure for 2-4 hours to obtain a two-component insulating potting composition.

[0014] Preferably, in the above step S1., the preparation method of tetramethylsiloxane is: under an argon atmosphere, allyl glycidyl ether and toluene are mixed in a mass ratio of 4 to 6:1, stirred evenly, hexachloroplatinic acid in an amount of 0.002 to 0.004 times the mass of toluene is added, the temperature is raised to 63 to 65°C, and tetramethyldisiloxane in an amount of 0.3 to 0.6 times the mass of toluene is added dropwise at a rate of 1 to 3 ml / min. After the reaction is kept warm for 20 to 40 minutes, the temperature is raised to 100 to 110°C, the reaction is continued for 6 to 8 hours, and the distillation is performed under reduced pressure, and the fraction at 190 to 200°C is collected to obtain tetramethylsiloxane.

[0015] Preferably, in the above step S3., the preparation method of the catalyst is: halloysite, chloroplatinic acid, isopropanol and anhydrous ethanol are mixed in a mass ratio of 15:0.1:0.2-0.3:50, stirred evenly, sonicated with 800-1000W ultrasound for 8-10 minutes, added with 0.02-0.04 times the mass of halloysite sodium bicarbonate, continued sonication for 8-10 minutes, stood for 24 hours, then heated to 70-80ml / min and rotary evaporated, dried to obtain the catalyst.

[0016] Preferably, in the above step S3., the preparation method of modified hydroxybenzene is: terephthalic acid and dichlorothionyl are mixed in a mass ratio of 2 to 3:10, heated to 70 to 80°C, refluxed for reaction for 2 to 4 hours, transferred to an ice bath, and methanol 1 to 3 times the mass of terephthalic acid is added dropwise at a rate of 1 to 3 ml / min, heated to 50 to 60°C, kept warm for reaction for 40 to 60 minutes, allowed to stand for precipitation, filtered, and the filter residue was mixed with methanol in a mass ratio of 1:10 to 12, hydrazine hydrate 2 to 3 times the mass of the filter residue was added, heated to 50 to 60°C, kept warm for reaction for 10 to 20 minutes, 2-hydroxy-1-naphthaldehyde of the same mass as the filter residue was added, the reaction was continued for 2 to 3 hours, cooled to room temperature and filtered to obtain modified hydroxybenzene.

[0017] Compared with the prior art, the beneficial effects achieved by the present invention are:

[0018] When preparing the two-component insulating potting composition of the present invention, the modified epoxy resin and the hyperbranched epoxy resin are mixed to obtain the composition;

[0019] The modified epoxy resin is prepared by adding bishydroxytetramethyldisiloxane when bisphenol A and epichlorohydrin are condensed under alkaline conditions. The bishydroxytetramethyldisiloxane is prepared by reacting tetramethylsiloxane with methanol. Long-chain disiloxane with hydroxyl groups is introduced into the epoxy resin to form a modified epoxy resin with a higher crosslinking degree, thereby enhancing the flame retardancy of the potting composition.

[0020] The hyperbranched epoxy resin is prepared by reacting 1,1,3,3-tetramethyldisiloxane with allyl glycidyl ether, and then reacting with vinyl silicone resin and modified hydroxybenzene. The modified hydroxybenzene is prepared by reacting terephthalic acid, 2-hydroxy-1-naphthaldehyde, dichlorothionyl and hydrazine hydrate. 2-Hydroxy-1-naphthaldehyde is grafted onto the carboxyl group of terephthalic acid to form a benzene ring structure and a dihydroxy structure, which is introduced into the hyperbranched epoxy resin containing a silicon skeleton. The modified hydroxybenzene enters the dendritic structure to enhance the heat dissipation of the hyperbranched epoxy resin. DETAILED DESCRIPTION

[0021] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0022] In order to more clearly illustrate the method provided by the present invention, the following examples are used to describe in detail the index testing methods of the two-component insulating potting compositions prepared in the examples and comparative examples as follows:

[0023] Flame retardancy: The two-component insulating potting compositions prepared in the same embodiment and comparative example were subjected to flame retardancy test according to GB / T2408.

[0024] Heat dissipation: The thermal conductivity of the two-component insulating potting composition prepared in the same embodiment and comparative example was tested according to GB / T10297.

[0025] Example 1

[0026] The preparation method of the two-component insulating potting composition in this embodiment is as follows:

[0027] S1. The preparation method of tetramethylsiloxane is as follows: in an argon atmosphere, allyl glycidyl ether and toluene are mixed in a mass ratio of 4:1, stirred evenly, hexachloroplatinic acid (0.002 times the mass of toluene) is added, the temperature is raised to 63°C, tetramethyldisiloxane (0.3 times the mass of toluene) is added dropwise at a rate of 1 ml / min, the temperature is kept for reaction for 20 minutes, the temperature is raised to 100°C, the temperature is kept for reaction for 6 hours, and the reduced pressure distillation is performed to collect the fraction of 190-200°C to obtain tetramethylsiloxane; in an argon atmosphere, tetramethylsiloxane and methanol are mixed in a mass ratio of 1:4, stirred evenly, trifluoromethylsulfonic acid (0.02 times the mass of tetramethylsiloxane) is added, the temperature is raised to 63°C, the temperature is refluxed for reaction for 8 hours, and the distillation is performed at normal pressure and pressure, and the fraction of 220-230°C is collected to obtain bishydroxytetramethyldisiloxane;

[0028] S2. Mix bisphenol A, epichlorohydrin and bishydroxytetramethyldisiloxane in a mass ratio of 1:5:0.1, heat and dissolve, add 0.02 times the mass of bisphenol A as a catalyst benzyltrimethylammonium bromide, heat to 90°C, react for 4 hours, rotary evaporate, add 8% sodium hydroxide solution twice the mass of bisphenol A, cool to 68°C, react for 6 hours, add 0.1 times the mass of bisphenol A in methyl isobutyl ketone at a rate of 1 ml / min, stir evenly and filter, wash the filtrate with deionized water 8 times, rotary evaporate again, add 0.02 times the mass of bisphenol A in ethyl acetate, stir evenly and filter again, rotary evaporate, and finally dry to obtain a modified epoxy resin;

[0029] S3. A 3% mass fraction of allyl magnesium bromide solution was mixed with phenyltrichlorosilane in a mass ratio of 30:1, transferred to an ice bath for reaction for 24 hours, a saturated sodium chloride solution of 5 times the mass of phenyltrichlorosilane was added, stirred evenly and filtered, and the temperature was raised to 68°C, the vacuum degree was adjusted to 600Pa, and the vinyl silicone resin was obtained by rotary evaporation; terephthalic acid and thionyl chloride were mixed in a mass ratio of 2:10, heated to 70°C and refluxed for 2 hours, transferred to an ice bath, and methanol of 1 times the mass of terephthalic acid was added dropwise at a rate of 1 ml / min, heated to 50°C, kept warm for reaction for 40 minutes, allowed to settle, filtered, and the residue was mixed with methanol in a mass ratio of 1:10, hydrazine hydrate of 2 times the mass of the residue was added, heated to 50°C, kept warm for reaction for 10 minutes, and 2-hydroxy-1-naphthaldehyde of the same mass was added for filtration, The reaction was continued for 2 hours, and the mixture was cooled to room temperature and filtered to obtain modified hydroxybenzene; halloysite, chloroplatinic acid, isopropanol and anhydrous ethanol were mixed in a mass ratio of 15:0.1:0.2:50, and then ultrasonicated for 8 minutes with an 800W ultrasonic wave, and sodium bicarbonate 0.02 times the mass of halloysite was added, and the ultrasonic wave was continued for 8 minutes. After standing for 24 hours, the temperature was raised to 70 ml / min and rotary evaporated, and dried to obtain a catalyst; 1,1,3,3,-tetramethyldisiloxane, allyl glycidyl ether and catalyst were heated to 68°C in a mass ratio of 20:6:6, and reacted for 10 hours, and then 0.3 times the mass of the catalyst and tetrahydrofuran 2 times the mass of the catalyst were added, and the reaction was continued for 10 hours, and the mixture was filtered and heated to 125°C, and the vacuum degree was adjusted to 600 Pa, and rotary evaporated to obtain a hyperbranched epoxy resin;

[0030] S4. The modified epoxy resin, hyperbranched epoxy resin and triethylamine were mixed in a mass ratio of 8:1:0.01, stirred evenly and transferred to a mold, heated to 92° C., and cured for 2 hours to obtain a two-component insulating potting composition.

[0031] Example 2

[0032] The preparation method of the two-component insulating potting composition in this embodiment is as follows:

[0033] S1. The preparation method of tetramethylsiloxane is as follows: in an argon atmosphere, allyl glycidyl ether and toluene are mixed in a mass ratio of 5:1, stirred evenly, hexachloroplatinic acid (0.003 times the mass of toluene) is added, the temperature is raised to 64°C, tetramethyldisiloxane (0.45 times the mass of toluene) is added dropwise at a rate of 2 ml / min, the temperature is kept to react for 30 minutes, the temperature is raised to 105°C, the temperature is kept to react for 7 hours, and the reduced pressure distillation is performed to collect the fraction of 190-200°C to obtain tetramethylsiloxane; in an argon atmosphere, tetramethylsiloxane and methanol are mixed in a mass ratio of 1:6, stirred evenly, trifluoromethylsulfonic acid (0.03 times the mass of tetramethylsiloxane) is added, the temperature is raised to 64°C, the temperature is refluxed for 9 hours, and the distillation is performed at normal pressure and pressure, and the fraction of 220-230°C is collected to obtain bishydroxytetramethyldisiloxane;

[0034] S2. Mix bisphenol A, epichlorohydrin and bishydroxytetramethyldisiloxane in a mass ratio of 1:6:0.2, heat and dissolve, add 0.03 times the mass of bisphenol A as a catalyst benzyltrimethylammonium bromide, heat to 95°C, react for 5 hours, rotary evaporate, add 3 times the mass of bisphenol A as a sodium hydroxide solution with a mass fraction of 10%, cool to 70°C, react for 7 hours, add 0.15 times the mass of bisphenol A as methyl isobutyl ketone at a rate of 2 ml / min, stir evenly and filter, wash the filtrate with deionized water 9 times, rotary evaporate again, add 0.04 times the mass of bisphenol A as a catalyst ethyl acetate, stir evenly and filter again, rotary evaporate, and finally dry to obtain a modified epoxy resin;

[0035] S3. Mix a 5% mass fraction of allyl magnesium bromide solution with phenyltrichlorosilane in a mass ratio of 40:2, transfer to an ice bath for reaction for 24 hours, add a saturated sodium chloride solution of 6 times the mass of phenyltrichlorosilane, stir evenly and filter, and heat to 70°C, adjust the vacuum degree to 650Pa, and rotary evaporate to obtain a vinyl silicone resin; mix terephthalic acid and dichlorothionyl in a mass ratio of 2.5:10, heat to 75°C and reflux for 3 hours, transfer to an ice bath, add methanol twice the mass of terephthalic acid at a rate of 2 ml / min, heat to 55°C, keep warm for 50 minutes, let stand and precipitate, filter and mix the residue with methanol in a mass ratio of 1:11, add hydrazine hydrate 2.5 times the mass of the residue, heat to 55°C, keep warm for 15 minutes, add 2-hydroxy-1-naphthaldehyde of the same mass as the filtration, and continue React for 2.5 hours, cool to room temperature and filter to obtain modified hydroxybenzene; halloysite, chloroplatinic acid, isopropanol and anhydrous ethanol are mixed in a mass ratio of 15:0.1:0.25:50, and then ultrasonicated with 900W ultrasound for 9 minutes, and sodium bicarbonate 0.03 times the mass of halloysite is added, and ultrasonication is continued for 9 minutes. After standing for 24 hours, the temperature is raised to 75ml / min and rotary evaporated, and dried to obtain a catalyst; 1,1,3,3,-tetramethyldisiloxane, allyl glycidyl ether and catalyst are heated to 70°C in a mass ratio of 20.5:6:6, and react for 11 hours, and then 0.35 times the mass of the catalyst The vinyl silicone resin and 2.5 times the mass of the catalyst The tetrahydrofuran is added, and the reaction is continued for 11 hours, and the suction is filtered and the temperature is raised to 130°C, and the vacuum degree is adjusted to 650Pa, and rotary evaporated to obtain a hyperbranched epoxy resin;

[0036] S4. The modified epoxy resin, hyperbranched epoxy resin and triethylamine were mixed in a mass ratio of 9:1:0.02, stirred evenly and transferred to a mold, heated to 94° C., and cured for 3 hours to obtain a two-component insulating potting composition.

[0037] Example 3

[0038] The preparation method of the two-component insulating potting composition in this embodiment is as follows:

[0039] S1. The preparation method of tetramethylsiloxane is as follows: in an argon atmosphere, allyl glycidyl ether and toluene are mixed in a mass ratio of 6:1, stirred evenly, hexachloroplatinic acid (0.004 times the mass of toluene) is added, the temperature is raised to 65°C, tetramethyldisiloxane (0.6 times the mass of toluene) is added dropwise at a rate of 3 ml / min, the temperature is kept for reaction for 40 minutes, the temperature is raised to 110°C, the temperature is kept for reaction for 8 hours, and the reduced pressure distillation is performed to collect the fraction of 190-200°C to obtain tetramethylsiloxane; in an argon atmosphere, tetramethylsiloxane and methanol are mixed in a mass ratio of 1:8, stirred evenly, trifluoromethylsulfonic acid (0.04 times the mass of tetramethylsiloxane) is added, the temperature is raised to 65°C, the temperature is refluxed for reaction for 10 hours, and the distillation is performed at normal pressure and pressure, and the fraction of 220-230°C is collected to obtain bishydroxytetramethyldisiloxane;

[0040] S2. Mix bisphenol A, epichlorohydrin and bishydroxytetramethyldisiloxane in a mass ratio of 1:8:0.3, heat and dissolve, add 0.04 times the mass of bisphenol A as a catalyst benzyltrimethylammonium bromide, heat to 100°C, react for 6 hours, rotary evaporate, add 12% sodium hydroxide solution with a mass fraction of 4 times the mass of bisphenol A, cool to 72°C, react for 8 hours, add 0.2 times the mass of bisphenol A in methyl isobutyl ketone at a rate of 3 ml / min, stir evenly and filter, wash the filtrate with deionized water 10 times, rotary evaporate again, add 0.06 times the mass of bisphenol A in ethyl acetate, stir evenly and filter again, rotary evaporate, and finally dry to obtain a modified epoxy resin;

[0041] S3. Mix 8% allyl magnesium bromide solution with phenyltrichlorosilane in a mass ratio of 50:3, transfer to an ice bath for reaction for 24 hours, add 7 times the mass of phenyltrichlorosilane saturated sodium chloride solution, stir evenly and filter, heat to 72°C, adjust the vacuum degree to 700Pa, and rotary evaporate to obtain a vinyl silicone resin; mix terephthalic acid and thionyl chloride in a mass ratio of 3:10, heat to 80°C and reflux for 4 hours, transfer to an ice bath, add methanol 3 times the mass of terephthalic acid at a rate of 3 ml / min, heat to 60°C, keep warm for 60 minutes, let stand for precipitation, filter and mix the residue with methanol in a mass ratio of 1:12, add hydrazine hydrate 3 times the mass of the residue, heat to 60°C, keep warm for 20 minutes, add 2-hydroxy-1-naphthaldehyde of the same mass as the filtration residue, and continue The reaction was continued for 3 hours, and the mixture was cooled to room temperature and filtered to obtain modified hydroxybenzene; halloysite, chloroplatinic acid, isopropanol and anhydrous ethanol were mixed in a mass ratio of 15:0.1:0.3:50, and then ultrasonicated for 10 minutes with a 1000W ultrasonic wave, and sodium bicarbonate 0.04 times the mass of halloysite was added, and the ultrasonic wave was continued for 10 minutes. After standing for 24 hours, the temperature was raised to 80ml / min and rotary evaporated, and dried to obtain a catalyst; 1,1,3,3,-tetramethyldisiloxane, allyl glycidyl ether and catalyst were heated to 72°C in a mass ratio of 21:6:6, and reacted for 12 hours, and then 0.4 times the mass of the catalyst The vinyl silicone resin and the catalyst mass of 3 tetrahydrofuran were added, and the reaction was continued for 12 hours, and the mixture was filtered and heated to 135°C, and the vacuum degree was adjusted to 700Pa, and rotary evaporated to obtain a hyperbranched epoxy resin;

[0042] S4. The modified epoxy resin, hyperbranched epoxy resin and triethylamine were mixed in a mass ratio of 10:1:0.03, stirred evenly and transferred to a mold, heated to 96° C., and cured for 4 hours to obtain a two-component insulating potting composition.

[0043] Comparative Example 1

[0044] The composition of Comparative Example 1 is the same as that of Example 2. The difference between the preparation method of the two-component insulating potting composition and that of Example 2 is that the modified epoxy resin is prepared by adding tetramethylsiloxane to the condensation of bisphenol A and epichlorohydrin under alkaline conditions.

[0045] Comparative Example 2

[0046] The composition of Comparative Example 2 is the same as that of Example 2. The difference between the preparation method of the two-component insulating potting composition and that of Example 2 is that the two-component insulating potting composition is prepared by blending bisphenol A epoxy resin and hyperbranched epoxy resin.

[0047] Comparative Example 3

[0048] The composition of Comparative Example 3 is the same as that of Example 2. The difference between the preparation method of the two-component insulating potting composition and that of Example 2 is that the hyperbranched epoxy resin is prepared by reacting 1,1,3,3-tetramethyldisiloxane with allyl glycidyl ether and then with vinyl silicone resin.

[0049] Comparative Example 4

[0050] The composition of Comparative Example 4 is the same as that of Example 2. The difference between the preparation method of the two-component insulating potting composition and that of Example 2 is that the hyperbranched epoxy resin is prepared by reacting 1,1,3,3-tetramethyldisiloxane with allyl glycidyl ether and then with modified hydroxybenzene.

[0051] Effect example

[0052] Table 1 below shows the performance analysis results of the two-component insulating potting compositions prepared using Examples 1 to 3 of the present invention and Comparative Examples 1 to 4:

[0053] Table 1

[0054]

[0055]

[0056] By comparing the experimental data of the examples and the comparative examples in Table 1, it can be clearly found that the two-component insulating potting compositions prepared using Examples 1, 2 and 3 have excellent peel strength and thermal stability.

[0057] From the comparison of the experimental data of Example 1, Example 2, Example 3 and Comparative Example 1, Comparative Example 2, it can be found that the modified epoxy resin is obtained by adding bishydroxytetramethyldisiloxane when bisphenol A and epichlorohydrin are condensed under alkaline conditions, and introducing long-chain disiloxane with hydroxyl groups into the epoxy resin to form a modified epoxy resin with a higher degree of crosslinking, thereby enhancing the flame retardancy of the potting composition.

[0058] From the comparison of the experimental data of Example 1, Example 2, Example 3 and Comparative Example 3, Comparative Example 4, it can be found that the hyperbranched epoxy resin is prepared by reacting 1,1,3,3-tetramethyldisiloxane with allyl glycidyl ether, and then reacting with a vinyl silicone resin and modified hydroxybenzene. 2-hydroxy-1-naphthaldehyde is grafted onto the carboxyl group of terephthalic acid to form a modified hydroxybenzene having a benzene ring structure and a dihydroxy structure and having a hydroxyl group, which is introduced into the hyperbranched epoxy resin containing a silicon skeleton. The modified hydroxybenzene enters the dendritic structure, thereby enhancing the heat dissipation of the hyperbranched epoxy resin.

[0059] Obviously, the above embodiments are merely examples for clearly illustrating the embodiments of the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. However, these obvious changes or modifications derived from the spirit of the present invention are still within the scope of protection of the present invention.

Claims

1. A two-component insulating potting composition, characterized in that: The two-component insulating potting composition is prepared by blending a modified epoxy resin and a hyperbranched epoxy resin.

2. A two-component insulating potting composition according to claim 1, characterized in that: The modified epoxy resin is prepared by adding bishydroxytetramethyldisiloxane to condense bisphenol A and epichlorohydrin under alkaline conditions; the bishydroxytetramethyldisiloxane is prepared by reacting tetramethylsiloxane with methanol.

3. A two-component insulating potting composition according to claim 1, characterized in that: The hyperbranched epoxy resin is prepared by reacting 1,1,3,3-tetramethyldisiloxane with allyl glycidyl ether, and then reacting with vinyl silicone resin and modified hydroxybenzene.

4. A two-component insulating potting composition according to claim 1, characterized in that: The modified hydroxybenzene is prepared by reacting terephthalic acid, 2-hydroxy-1-naphthaldehyde, thionyl chloride and hydrazine hydrate.

5. A method for preparing a two-component insulating potting composition as claimed in claim 1, characterized in that: The specific steps include: S1. Under an argon atmosphere, tetramethylsiloxane and methanol are mixed in a mass ratio of 1:4 to 8, and after stirring evenly, 0.02 to 0.04 times the mass of tetramethylsiloxane trifluoromethylsulfonic acid is added, the temperature is raised to 63 to 65°C, and after reflux reaction for 8 to 10 hours, atmospheric distillation and pressure distillation are performed in sequence, and the fraction at 220 to 230°C is collected to obtain bishydroxytetramethyldisiloxane; S2. Mix bisphenol A, epichlorohydrin and bishydroxytetramethyldisiloxane in a mass ratio of 1:5-8:0.1-0.3, heat and dissolve, add 0.02-0.04 times the mass of bisphenol A as a catalyst benzyltrimethylammonium bromide, heat to 90-100°C, react for 4-6 hours, rotary evaporate, add 2-4 times the mass of bisphenol A and a mass fraction of 8-12% sodium hydroxide solution, cool to 68-72°C, react for 6-8 hours, add 0.1-0.2 times the mass of bisphenol A in methyl isobutyl ketone at a rate of 1-3 ml / min, stir evenly and filter, wash the filtrate with deionized water for 8-10 times, rotary evaporate again, add 0.02-0.06 times the mass of bisphenol A in ethyl acetate, stir evenly and filter again, rotary evaporate, and finally dry to obtain a modified epoxy resin; S3. 1,1,3,3,-tetramethyldisiloxane, allyl glycidyl ether and catalyst are heated to 68-72°C in a mass ratio of 20-21:6:6, react for 10-12h, then add 0.3-0.4 times the mass of the catalyst of vinyl silicone resin and 2-3 times the mass of the catalyst of tetrahydrofuran, continue to react for 10-12h, filter and heat to 125-135°C, adjust the vacuum degree to 600-700Pa, and rotary evaporate to obtain a hyperbranched epoxy resin; S4. Combine the modified epoxy resin, hyperbranched epoxy resin and triethylamine in a mass ratio of 8-10:1:0.01-0.03, stir evenly and transfer to a mold, heat to 92-96° C., and cure for 2-4 hours to obtain a two-component insulating potting composition.

6. The method for preparing a two-component insulating potting composition according to claim 5, characterized in that: In the above step S1., the preparation method of tetramethylsiloxane is: under an argon atmosphere, allyl glycidyl ether and toluene are mixed in a mass ratio of 4 to 6:1, and hexachloroplatinic acid is added evenly with stirring at a mass ratio of 0.002 to 0.004 times the mass of toluene, and the temperature is raised to 63 to 65°C, and tetramethyldisiloxane is added dropwise at a rate of 1 to 3 ml / min at a mass ratio of 0.3 to 0.6 times the mass of toluene. After the reaction is kept warm for 20 to 40 minutes, the temperature is raised to 100 to 110°C, and the reaction is continued for 6 to 8 hours. The distillation is carried out under reduced pressure, and the fraction at 190 to 200°C is collected to obtain tetramethylsiloxane.

7. The method for preparing a two-component insulating potting composition according to claim 5, characterized in that: In the above step S3., the preparation method of the catalyst is: halloysite, chloroplatinic acid, isopropanol and anhydrous ethanol are mixed in a mass ratio of 15:0.1:0.2-0.3:50, stirred evenly, ultrasonicated with 800-1000W ultrasound for 8-10 minutes, added with 0.02-0.04 times the mass of halloysite sodium bicarbonate, continued ultrasonication for 8-10 minutes, stood for 24 hours, then heated to 70-80ml / min and rotary evaporated, dried to obtain the catalyst.

8. The method for preparing a two-component insulating potting composition according to claim 5, characterized in that: In the above step S3., the preparation method of the vinyl silicone resin is: mixing a 3-8% mass fraction of allyl magnesium bromide solution and phenyltrichlorosilane in a mass ratio of 30-50:1-3, transferring to an ice bath for reaction for 24 hours, adding a saturated sodium chloride solution 5-7 times the mass of phenyltrichlorosilane, stirring evenly and then filtering, and heating to 68-72°C, adjusting the vacuum degree to 600-700Pa, and rotary evaporating to obtain the vinyl silicone resin.

9. The method for preparing a two-component insulating potting composition according to claim 5, characterized in that: In the above step S3., the preparation method of modified hydroxybenzene is: terephthalic acid and dichlorothionyl are mixed in a mass ratio of 2 to 3:10, heated to 70 to 80°C, refluxed for reaction for 2 to 4 hours, transferred to an ice bath, and methanol 1 to 3 times the mass of terephthalic acid is added dropwise at a rate of 1 to 3 ml / min, heated to 50 to 60°C, kept warm for reaction for 40 to 60 minutes, allowed to stand for precipitation, filtered, and the filter residue was mixed with methanol in a mass ratio of 1:10 to 12, hydrazine hydrate 2 to 3 times the mass of the filter residue was added, heated to 50 to 60°C, kept warm for reaction for 10 to 20 minutes, 2-hydroxy-1-naphthaldehyde of the same mass as the filter residue was added, the reaction was continued for 2 to 3 hours, cooled to room temperature and filtered to obtain modified hydroxybenzene.

Images