Silicon-molybdenum co-modified epoxy resin, microwave-absorbing coating and microwave-absorbing honeycomb and preparation method and application thereof

Abstract

The present invention discloses a silicon-molybdenum co-modified epoxy resin, a microwave-absorbing coating and a microwave-absorbing honeycomb and a preparation method and application thereof. The silicon-molybdenum co-modified epoxy resin is synthesized by using hydrogen-terminated silicone oil, a glycidyl ether containing a carbon-carbon double bond and ammonium molybdate as raw materials, and Si-O-Si bonds and O-Mo-O bonds are introduced into the epoxy resin to obtain the silicon-molybdenum co-modified epoxy resin. The synergistic effect of the two significantly improves the bond energy in the silicon-molybdenum co-modified epoxy resin, and the formed cross-linked network is more solid. Therefore, the above-mentioned silicon-molybdenum co-modified epoxy resin further improves the glass transition temperature and significantly improves its mechanical properties at high temperatures. By using a microwave-absorbing coating containing silicon-molybdenum co-modified epoxy resin, the mechanical properties of the microwave-absorbing honeycomb at high temperatures can be guaranteed, thereby ensuring its microwave-absorbing performance.

Description

Technical Field

[0001] The invention relates to the field of chemical materials, and in particular to a silicon-molybdenum co-modified epoxy resin, a microwave-absorbing coating and a microwave-absorbing honeycomb, and a preparation method and application thereof. Background Art

[0002] With the widespread popularity of electronic devices, electromagnetic pollution and electromagnetic interference are becoming more and more common, and the impact of electromagnetic radiation on the environment is increasing. Electromagnetic radiation can cause direct and indirect harm to the human body through thermal effects, non-thermal effects, and cumulative effects. Absorbing materials can absorb or greatly reduce the electromagnetic wave energy received on their surface, thereby reducing electromagnetic interference. In engineering applications, absorbing honeycombs are favored by designers as a lightweight absorbing material with excellent mechanical and electromagnetic properties.

[0003] Traditional absorbing honeycomb materials have good mechanical properties due to the mesh structure of the honeycomb core material. However, at high temperatures, the mechanical properties of traditional absorbing honeycomb materials decrease significantly, the honeycomb structure will be destroyed, and its absorbing performance will be reduced. Summary of the invention

[0004] Based on this, the present invention provides a silicon-molybdenum co-modified epoxy resin, an absorbing coating and an absorbing honeycomb, and a preparation method and application thereof. When the silicon-molybdenum co-modified epoxy resin is used to prepare the absorbing coating, the absorbing coating also has certain mechanical properties. Therefore, by using the absorbing coating containing the silicon-molybdenum co-modified epoxy resin, the mechanical properties of the absorbing honeycomb at high temperature can be guaranteed, thereby ensuring its absorbing performance.

[0005] The silicon-molybdenum co-modified epoxy resin, microwave-absorbing coating and microwave-absorbing honeycomb and the preparation method and application thereof of the present invention are achieved through the following technical scheme.

[0006] The present invention provides a silicon-molybdenum co-modified epoxy resin, the structural formula of which is shown in Formula I:

[0007] I;

[0008] Wherein, n and m are each independently selected from integers of 1 to 10,

[0009] R 5 , R 6 Each is independently selected from -H, C1-C4 substituted or unsubstituted straight-chain alkyl, or C1-C4 substituted or unsubstituted branched-chain alkyl.

[0010] The present invention also provides a method for preparing the above silicon-molybdenum co-modified epoxy resin, comprising the following steps:

[0011] S11: preparing a first mixed solution, wherein the first mixed solution comprises hydrogen-terminated silicone oil, a catalyst and a first solvent;

[0012] S12: heating the first mixed solution to 70° C. to 90° C., adding glycidyl ether containing a carbon-carbon double bond, and reacting for 20 min to 40 min to obtain a first reactant, wherein the glycidyl ether containing a carbon-carbon double bond has the following structural formula: , where R 5 , R 6 Each is independently selected from -H, C1~C4 substituted or unsubstituted straight-chain alkyl, or C1~C4 substituted or unsubstituted branched-chain alkyl;

[0013] S13: preparing a second mixed solution, wherein the second mixed solution comprises the first reactant, a strong inorganic acid, a second solvent and ammonium molybdate, reacting for 30 minutes to 60 minutes to obtain a second reactant, and removing volatile substances from the second reactant.

[0014] In one embodiment, in step S11, the first mixed solution contains 20 to 30 parts of the terminal hydrogenated silicone oil, 2 to 3 parts of the catalyst, 0.2 to 0.3 parts of the inhibitor and 200 to 300 parts of the first solvent, in parts by weight, wherein the first solvent is tetrahydrofuran, the catalyst is chloroplatinic acid, the inhibitor is p-hydroxyanisole, and the relative molecular mass of the terminal hydrogenated silicone oil is 500 to 600.

[0015] In one embodiment, in step S13, the second mixed solution is prepared from the following raw materials in parts by weight: 50 to 80 parts of the first reactant, 1 to 2 parts of ammonium molybdate, 1 to 2 parts of a strong inorganic acid, and 50 to 60 parts of the second solvent, wherein the second solvent comprises tetrahydrofuran and deionized water in a mass ratio of 1:1.

[0016] The present invention also provides a silicon-molybdenum co-modified epoxy resin, which is prepared by the above-mentioned preparation method of the silicon-molybdenum co-modified epoxy resin.

[0017] The present invention further provides an absorbing coating, which is prepared from the following raw materials in parts by weight: 50 to 90 parts of the above-mentioned silicon-molybdenum co-modified epoxy resin, 3 to 10 parts of a curing agent, 10 to 40 parts of a filler, 3 to 7 parts of a dispersant, 0.5 to 2 parts of a leveling agent, 0.8 to 1.2 parts of an accelerator and 1 to 3 parts of a defoaming agent.

[0018] In one embodiment, the curing agent is selected from at least one of anhydride latent curing agents, dicyandiamide latent curing agents and imidazole latent curing agents, and the latent period of the curing agent is more than one month; and / or

[0019] The filler is selected from at least one of graphene, carbon nanotubes, conductive graphite and carbon black; and / or

[0020] The dispersant is selected from at least one of BYK108 and 904S; and / or

[0021] The leveling agent is selected from at least one of BYK320, BYK333 and BYK358N; and / or

[0022] The accelerator is triphenylphosphine; and / or

[0023] The defoamer is a silicone defoamer.

[0024] The present invention also provides a method for preparing a wave-absorbing honeycomb, comprising the following steps:

[0025] S21: preparing materials according to the raw material formula of the radar absorbing coating as described above;

[0026] S22: drying the honeycomb core material, and immersing the dried honeycomb core material in the radar absorbing coating;

[0027] S23: drying the impregnated honeycomb core material to obtain an impregnated honeycomb core material, and drying and curing the impregnated honeycomb core material.

[0028] In one embodiment, in step S22, the honeycomb core material is dried at 100° C. to 140° C. for 1 h to 2 h, and the dried honeycomb core material is immersed in the radar absorbing coating by completely immersing the dried honeycomb core material for 5 min to 10 min; and / or

[0029] In step S23, drying and curing the impregnated honeycomb core material includes a pre-curing step and a secondary drying and curing step, wherein the pre-curing step includes heating the impregnated honeycomb core material to 100°C~140°C, maintaining for 25min~35min, and then cooling to 40°C~80°C to obtain the pre-cured impregnated honeycomb core material; the secondary drying and curing step includes heating the pre-cured impregnated honeycomb core material to 100°C~140°C, maintaining for 25min~35min, then heating to 160°C~200°C, maintaining for 1h~2h, and then cooling to 40°C~80°C.

[0030] The present invention also provides a wave-absorbing honeycomb, which is made by the preparation method of the wave-absorbing honeycomb.

[0031] The present invention further provides the use of the above-mentioned wave-absorbing honeycomb in the preparation of a thermal radiation detector, a thermal radiation imager or a non-destructive detector.

[0032] Compared with the prior art, the silicon-molybdenum co-modified epoxy resin of the present invention has the following beneficial effects:

[0033] By introducing Si-O-Si bonds and O-Mo-O bonds into epoxy resin, silicon-molybdenum co-modified epoxy resin is obtained. The synergistic effect of the two significantly improves the bond energy in the silicon-molybdenum co-modified epoxy resin, and the formed cross-linked network is more solid. Therefore, the silicon-molybdenum co-modified epoxy resin further increases the glass transition temperature and significantly improves its mechanical properties at high temperatures. By using the microwave-absorbing coating containing silicon-molybdenum co-modified epoxy resin, the mechanical properties of the microwave-absorbing honeycomb at high temperatures can be guaranteed, thereby ensuring its microwave-absorbing performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 The NMR of Example 3 1 H result graph.

[0035] Figure 2 The NMR of Example 3 13 C result graph. DETAILED DESCRIPTION

[0036] The present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present invention more thoroughly understood. Of course, they are only examples, and the purpose is not to limit the present invention. In addition, the present invention can repeat reference numbers and / or letters in different examples. This repetition is for the purpose of simplicity and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed.

[0037] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the invention, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. In the description of the present invention, the meaning of "several" is at least one, such as one, two, etc., unless otherwise clearly and specifically defined.

[0038] In the present invention, "alkyl" may represent a linear, branched and / or cyclic alkyl group. The carbon number of the alkyl group may be 1 to 50, 1 to 30, 1 to 20, 1 to 10 or 1 to 6. A phrase containing this term, for example, "C1-9 alkyl" refers to an alkyl group containing 1 to 9 carbon atoms, and each occurrence may be independently C1 alkyl, C2 alkyl, C3 alkyl, C4 alkyl, C5 alkyl, C6 alkyl, C7 alkyl, C8 alkyl or C9 alkyl. Non-limiting examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, isobutyl, 2-ethylbutyl, 3,3-dimethylbutyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, cyclopentyl, 1-methylpentyl, 3-methylpentyl, 2-ethylpentyl, 4-methyl-2-pentyl, n-hexyl, 1-methylhexyl, 2-ethylhexyl, 2-butylhexyl, cyclohexyl, 4-methylcyclohexyl, 4-tert-butylcyclohexyl, n-heptyl, 1-methylheptyl, 2,2-dimethylheptyl, 2-ethylheptyl, 2-butylheptyl, n-octyl, tert-octyl, 2-ethyloctyl, 2-butyloctyl, 2-hexyloctyl, 3 ,7-dimethyloctyl, cyclooctyl, n-nonyl, n-decyl, adamantyl, 2-ethyldecyl, 2-butyldecyl, 2-hexyldecyl, 2-octyldecyl, n-undecyl, n-dodecyl, 2-ethyldodecyl, 2-butyldodecyl, 2-hexyldodecyl, 2-octyldodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, 2-ethylhexadecyl, 2-butylhexadecyl, 2-hexylhexadecyl, 2-octylhexadecyl, n-heptadecyl, n-octadecyl, n-nonadecyl, n-eicosyl, 2-ethyleicosyl, 2-butyleicosyl, 2-hexyleicosyl, 2-octyleicosyl, n-heneicosyl, n-docosyl, n-tricosyl, n-tetracosyl, n-pentacosyl, n-hexacosyl, n-heptacosyl, n-octacosyl, n-nonacosyl, n-triacontyl, adamantane, etc.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0040] The present invention provides a silicon-molybdenum co-modified epoxy resin, the structural formula of which is shown in Formula I:

[0041] I;

[0042] Wherein, n and m are each independently selected from integers of 1 to 10,

[0043] R5 , R 6 Each is independently selected from -H, C1~C4 substituted or unsubstituted straight-chain alkyl, or C1~C4 substituted or unsubstituted branched-chain alkyl.

[0044] The present invention also provides a method for preparing the above-mentioned silicon-molybdenum co-modified epoxy resin, comprising the following steps S11 to S13.

[0045] Step S11: preparing a first mixed solution, wherein the first mixed solution comprises terminal hydrogen silicone oil, a catalyst, a polymerization inhibitor and a first solvent.

[0046] In a specific example, in parts by weight, the first mixed solution contains 20 to 30 parts of end-hydrogen silicone oil, 2 to 3 parts of catalyst, 0.2 to 0.3 parts of inhibitor and 200 to 300 parts of the first solvent, wherein the first solvent is tetrahydrofuran, the catalyst is chloroplatinic acid, and the inhibitor is p-hydroxyanisole.

[0047] Specifically, the relative molecular mass of the above-mentioned hydrogen-terminated silicone oil is 500-600.

[0048] Step S12: heating the first mixed solution to 70° C. to 90° C., adding glycidyl ether containing a carbon-carbon double bond, and reacting for 20 min to 40 min to obtain a first reactant.

[0049] In a specific example, the structural formula of the glycidyl ether containing a carbon-carbon double bond is as follows: , where R 5 , R 6 Each is independently selected from -H, C1~C4 substituted or unsubstituted straight-chain alkyl, or C1~C4 substituted or unsubstituted branched-chain alkyl.

[0050] Specifically, the heating temperature may be, for example, 75°C to 85°C, such as 75°C, 76°C, 77°C, 78°C, 79°C, 80°C, 81°C, 82°C, 83°C, 84°C or 85°C.

[0051] Furthermore, the reaction time can be, for example, 25 min to 35 min, for example, 25 min, 26 min, 27 min, 28 min, 29 min, 30 min, 31 min, 32 min, 33 min, 34 min or 35 min.

[0052] Step S13: preparing a second mixed solution, the second mixed solution comprising the first reactant, an inorganic strong acid, a second solvent and ammonium molybdate, reacting for 30 minutes to 60 minutes to obtain a second reactant, and removing volatile substances in the second reactant.

[0053] Furthermore, the reaction time can be, for example, 30 min, 32 min, 34 min, 36 min, 38 min, 40 min, 42 min, 44 min, 46 min, 48 min, 50 min, 52 min, 54 min, 56 min, 58 min or 60 min.

[0054] The second mixed solution comprises the following raw materials in parts by weight: 50-80 parts of the first reactant, 1-2 parts of ammonium molybdate, 1-2 parts of a strong inorganic acid and 50-60 parts of a second solvent, wherein the second solvent comprises tetrahydrofuran and deionized water in a mass ratio of 1:1.

[0055] Specifically, the method of removing the volatile substances in the second reactant may be, but is not limited to, a reduced pressure distillation method.

[0056] The silicon-molybdenum co-modified epoxy resin obtained by the preparation method significantly improves the bond energy in the silicon-molybdenum co-modified epoxy resin by introducing the synergistic effect of Si-O-Si bonds and O-Mo-O bonds, and the formed cross-linked network is more solid. Therefore, the silicon-molybdenum co-modified epoxy resin further increases the glass transition temperature and significantly improves its mechanical properties at high temperatures.

[0057] The present invention further provides an absorbing coating, which is prepared from the following raw materials in parts by weight: 50 to 90 parts of the above-mentioned silicon-molybdenum co-modified epoxy resin, 3 to 10 parts of a curing agent, 10 to 40 parts of a filler, 3 to 7 parts of a dispersant, 0.5 to 2 parts of a leveling agent, 0.8 to 1.2 parts of an accelerator and 1 to 3 parts of a defoaming agent.

[0058] The above-mentioned absorbing coating also includes 150-250 parts of a solvent, and the solvent is selected from at least one of tetrahydrofuran, toluene, chloroform, carbon tetrachloride, trimethylbenzene, xylene and toluene.

[0059] In a specific example, the curing agent is selected from at least one of anhydride latent curing agents, dicyandiamide latent curing agents and imidazole latent curing agents. In order to achieve a better curing effect, the latent period of the curing agent is more than one month.

[0060] The filler is selected from at least one of graphene, carbon nanotubes, conductive graphite and carbon black.

[0061] In a specific example, the dispersant is selected from at least one of BYK108 and Deqian 904S.

[0062] Furthermore, the leveling agent is selected from at least one of BYK320, BYK333 and BYK358N.

[0063] The above-mentioned accelerator is triphenylphosphine.

[0064] Furthermore, the defoaming agent is a silicone-based defoaming agent, and preferably the defoaming agent is 6800.

[0065] Due to the synergistic effect of the silicon-molybdenum co-modified epoxy resin, dispersant, leveling agent, filler, curing agent and defoaming agent, the absorbing coating has high dispersibility and can maintain a suspended state for a long time. When coated on a substrate, it reduces the generation of voids and improves the high-temperature resistant compressive strength retention rate, the low-temperature resistant compressive strength retention rate, the low-water resistant compressive strength retention rate and the high-temperature resistant shear strength retention rate.

[0066] The present invention also provides a method for preparing a wave-absorbing honeycomb, comprising the following steps S21 to S23.

[0067] Step S21: preparing materials according to the raw material formula of the radar absorbing coating as described above;

[0068] Step S22: Dry the honeycomb core material, and immerse the dried honeycomb core material in the radar absorbing coating.

[0069] In a specific example, in step S22, the honeycomb core material is dried at 100°C to 140°C for 1 hour to 2 hours, and the dried honeycomb core material is immersed in the radar absorbing coating by completely immersing the material for 5 minutes to 10 minutes.

[0070] Specifically, the drying temperature is preferably 115°C to 125°C, for example, 115°C, 118°C, 119°C, 120°C, 121°C, 122°C, 123°C or 125°C.

[0071] Furthermore, the drying time may be, for example, 1 h, 1.1 h, 1.2 h, 1.3 h, 1.4 h, 1.5 h, 1.6 h, 1.7 h, 1.8 h, 1.9 h or 2 h.

[0072] Furthermore, the immersion time may be, but is not limited to, 5 min, 6 min, 7 min, 8 min, 9 min or 10 min.

[0073] In order to have better contact with the radar absorbing coating, the honeycomb core material can be impregnated multiple times until the density of the honeycomb core material after impregnation increases to 52kg / m 3 The impregnation can be completed.

[0074] In order to achieve a better impregnation effect, dust on the surface of the honeycomb core material may be removed after step S21 and before step S22.

[0075] Step S23: drying the impregnated honeycomb core material to obtain an impregnated honeycomb core material, and drying and curing the impregnated honeycomb core material.

[0076] The drying and curing of the impregnated honeycomb core material includes a pre-curing step and a secondary drying and curing step.

[0077] Furthermore, the pre-curing step includes heating the impregnated honeycomb core material to 100° C. to 140° C., maintaining the temperature for 25 min to 35 min, and then cooling the temperature to 40° C. to 80° C. to obtain the pre-cured impregnated honeycomb core material.

[0078] Specifically, the impregnated honeycomb core material is heated to 110°C-130°C, for example, 110°C, 112°C, 114°C, 116°C, 118°C, 120°C, 122°C, 124°C, 126°C, 128°C or 130°C.

[0079] The holding time after the heating may be, but is not limited to, 25 min, 26 min, 27 min, 28 min, 29 min, 30 min, 31 min, 32 min, 33 min, 34 min or 35 min.

[0080] Furthermore, the re-drying and curing step includes heating the pre-cured impregnated honeycomb core material to 100°C~140°C, maintaining it for 25min~35min, then heating it to 160°C~200°C, maintaining it for 1h~2h, and finally cooling it to 40°C~80°C.

[0081] In a specific example, the pre-cured impregnated honeycomb core material is preferably heated to 110°C-130°C, maintained for 25min-35min, then heated to 170°C-190°C, maintained for 1h-2h, and then cooled to 40°C-60°C.

[0082] The absorbing honeycomb obtained by impregnating the honeycomb core material with the above-mentioned absorbing material can significantly improve the structure of the absorbing coating formed on the surface of the coated absorbing honeycomb, making it more solid, and improve the high-temperature compression strength retention rate, water-resistant compression strength retention rate, low-temperature compression strength retention rate and high-temperature shear strength retention rate of the absorbing honeycomb, that is, ensure the mechanical properties of the absorbing honeycomb at high temperature and thus ensure its absorbing performance.

[0083] The following specific examples are provided to further illustrate the silicon-molybdenum co-modified epoxy resin, the absorbing coating and the absorbing honeycomb and the preparation method thereof. The raw materials of the following examples are mid-end hydrogen silicone oil purchased from Shanghai Sili Industry and Trade Co., Ltd., the dispersant is BYK108, the leveling agent is BYK320, the defoamer is purchased from Shanghai Tiger Polymer Technology Co., Ltd. with a brand of 6800, and the honeycomb core material is NRH type aramid paper honeycomb core material. Example 1

[0084] This embodiment provides a silicon-molybdenum co-modified epoxy resin, and the preparation method thereof is as follows.

[0085] 100g of terminal hydrogen silicone oil, 1g of polymerization inhibitor p-hydroxyanisole and 10g of 1% by mass chloroplatinic acid in tetrahydrofuran were added to a 1000ml four-necked flask equipped with a stirrer, a dropping funnel, a thermometer and a reflux condenser, and the above substances were heated to 80°C under stirring. At this temperature, 30g of allyl glycidyl ether was added dropwise using a separating funnel, and the reaction was continued under stirring.

[0086] After 30 minutes of reaction, 10 g of a mixed solution of ammonium molybdate and dilute hydrochloric acid was added, wherein the mass ratio of ammonium molybdate, HCl and distilled water in the mixed solution was 196:73:1960. At the end of the reaction, the reaction mixture was distilled under reduced pressure to remove volatile products. Example 2

[0087] This embodiment provides a silicon-molybdenum co-modified epoxy resin, and the preparation method thereof is as follows.

[0088] 100g of terminal hydrogen silicone oil, 1g of inhibitor p-hydroxyanisole and 10g of tetrahydrofuran solution of 1% chloroplatinic acid were added to a 1000ml four-necked flask equipped with a stirrer, a dropping funnel, a thermometer and a reflux condenser, and the above substances were heated to 80°C under stirring. At this temperature, 30g of allyl glycidyl ether was added dropwise with a separatory funnel within a certain period of time, and the stirring reaction was continued. After 30 minutes of reaction, a mixed solution of 15g of ammonium molybdate and dilute hydrochloric acid was added, wherein the mass ratio of ammonium molybdate, HCl and distilled water in the mixed solution was 196:73:1960. At the end of the reaction, the reaction mixture was distilled under reduced pressure to remove volatile products. Example 3

[0089] This embodiment provides a silicon-molybdenum co-modified epoxy resin, and the preparation method thereof is as follows.

[0090] 100g of terminal hydrogen silicone oil, 1g of inhibitor p-hydroxyanisole and 10g of tetrahydrofuran solution of 1% chloroplatinic acid were added to a 1000ml four-necked flask equipped with a stirrer, a dropping funnel, a thermometer and a reflux condenser, and the above substances were heated to 80°C under stirring. At this temperature, 30g of allyl glycidyl ether was added dropwise with a separatory funnel within a certain period of time, and the stirring reaction was continued. After 30 minutes of reaction, a mixed solution of 20g of ammonium molybdate and dilute hydrochloric acid was added, wherein the mass ratio of ammonium molybdate, HCl and distilled water in the mixed solution was 196:73:1960. At the end of the reaction, the reaction mixture was distilled under reduced pressure to remove volatile products. Example 4

[0091] This embodiment provides a silicon-molybdenum co-modified epoxy resin, and the preparation method thereof is as follows.

[0092] 100g of terminal hydrogen silicone oil, 1g of inhibitor p-hydroxyanisole and 10g of tetrahydrofuran solution of 1% chloroplatinic acid were added to a 1000ml four-necked flask equipped with a stirrer, a dropping funnel, a thermometer and a reflux condenser, and the above substances were heated to 80°C under stirring. At this temperature, 40g of allyl glycidyl ether was added dropwise with a separatory funnel within a certain period of time, and the stirring reaction was continued. After 30 minutes of reaction, a mixed solution of 10g of ammonium molybdate and dilute hydrochloric acid was added, wherein the mass ratio of ammonium molybdate, HCl and distilled water was 196:73:1960. At the end of the reaction, the reaction mixture was distilled under reduced pressure to remove volatile products. Example 5

[0093] This embodiment provides a silicon-molybdenum co-modified epoxy resin, and the preparation method thereof is as follows.

[0094] 100g of terminal hydrogen silicone oil, 1g of inhibitor p-hydroxyanisole and 10g of tetrahydrofuran solution of 1% chloroplatinic acid were added to a 1000ml four-necked flask equipped with a stirrer, a dropping funnel, a thermometer and a reflux condenser, and the above substances were heated to 80°C under stirring. At this temperature, 40g of allyl glycidyl ether was added dropwise with a separatory funnel within a certain period of time, and the stirring reaction was continued. After 30 minutes of reaction, a mixed solution of 15g of ammonium molybdate and dilute hydrochloric acid was added, wherein the mass ratio of ammonium molybdate, HCl and distilled water was 196:73:1960. At the end of the reaction, the reaction mixture was distilled under reduced pressure to remove volatile products. Example 6

[0095] This embodiment provides a silicon-molybdenum co-modified epoxy resin, and the preparation method thereof is as follows.

[0096] 100g of terminal hydrogen silicone oil, 1g of inhibitor p-hydroxyanisole and 10g of 1% tetrahydrofuran solution of chloroplatinic acid were added to a 1000ml four-necked flask equipped with a stirrer, a dropping funnel, a thermometer and a reflux condenser, and the above substances were heated to 80°C under stirring. At this temperature, 40g of allyl glycidyl ether was added dropwise with a separatory funnel within a certain period of time, and the stirring reaction was continued. After 30 minutes of reaction, a mixed solution of 20g of ammonium molybdate and dilute hydrochloric acid was added, wherein the mass ratio of ammonium molybdate, HCl and distilled water was 196:73:1960. At the end of the reaction, the reaction mixture was distilled under reduced pressure to remove volatile products. Example 7

[0097] This embodiment provides an absorbing coating and an absorbing honeycomb, wherein the absorbing coating comprises the following raw materials, measured in parts by weight: 60 parts of the silicon-molybdenum co-modified epoxy resin of Example 3, 3 parts of a curing agent dicyandiamide, 40 parts of filler carbon black, 5 parts of a dispersant BYK108, 1 part of a leveling agent BYK320, 2 parts of a defoaming agent 6800, 1 part of an accelerator, and 250 parts of a solvent toluene.

[0098] The preparation method of the microwave-absorbing honeycomb is as follows: the dust of the honeycomb core material is removed by an air sprayer, and the honeycomb core material is placed in a blast drying oven at 120°C for 1 hour. The honeycomb core material is immersed in the above-mentioned microwave-absorbing coating for multiple immersions, and each immersion is completely immersed for 5 minutes. After each immersion, it is hung to dry and pre-cured for 30 minutes before the next immersion, until the density of the honeycomb core material after immersion increases to 52kg / m 3 ; The honeycomb absorbing material that has been impregnated and aired for the last time is cured. The pre-curing procedure is: the room temperature is raised to 120°C within 1 hour, maintained for 30 minutes, and naturally cooled to below 60°C; the drying and curing procedure is: the room temperature is raised to 120°C within 1 hour; 120°C is kept for 0.5 hours, then raised to 180°C within 1 hour, 180°C is kept for 1.5 hours, and naturally cooled to below 60°C. Example 8

[0099] This embodiment provides an absorbing coating and an absorbing honeycomb, wherein the absorbing coating comprises the following raw materials, measured in parts by weight: 70 parts of the silicon-molybdenum co-modified epoxy resin of Example 3, 3 parts of a curing agent dicyandiamide, 10 parts of a filler carbon black, 5 parts of a dispersant BYK108, 1 part of a leveling agent BYK320, 2 parts of a defoaming agent 6800, 1 part of an accelerator, and 250 parts of a solvent toluene.

[0100] The preparation method of the microwave-absorbing honeycomb is as follows: the dust of the honeycomb core material is removed by an air sprayer, and the honeycomb core material is placed in a blast drying oven at 120°C for 1 hour. The honeycomb core material is immersed in the above-mentioned microwave-absorbing coating for multiple immersions, and each immersion is completely immersed for 5 minutes. After each immersion, it is hung to dry and pre-cured for 30 minutes before the next immersion, until the density of the honeycomb core material after immersion increases to 52kg / m 3 ; The honeycomb absorbing material that has been impregnated and aired for the last time is cured. The pre-curing procedure is: the room temperature is raised to 120°C within 1 hour, maintained for 30 minutes, and naturally cooled to below 60°C; the drying and curing procedure is: the room temperature is raised to 120°C within 1 hour; 120°C is kept for 0.5 hours, then raised to 180°C within 1 hour, 180°C is kept for 1.5 hours, and naturally cooled to below 60°C. Example 9

[0101] This embodiment provides an absorbing coating and an absorbing honeycomb, wherein the absorbing coating comprises the following raw materials, measured in parts by weight: 55 parts of the silicon-molybdenum co-modified epoxy resin of Example 3, 3 parts of a curing agent dicyandiamide, 40 parts of filler carbon black, 5 parts of a dispersant BYK108, 1 part of a leveling agent BYK320, 2 parts of a defoaming agent 6800, 1 part of an accelerator, and 250 parts of a solvent toluene.

[0102] The preparation method of the microwave-absorbing honeycomb is as follows: the dust of the honeycomb core material is removed by an air sprayer, and the honeycomb core material is placed in a blast drying oven at 120°C for 1 hour. The honeycomb core material is immersed in the above-mentioned microwave-absorbing coating for multiple immersions, and each immersion is completely immersed for 5 minutes. After each immersion, it is hung to dry and pre-cured for 30 minutes before the next immersion, until the density of the honeycomb core material after immersion increases to 52kg / m 3 ; The honeycomb absorbing material that has been impregnated and aired for the last time is cured. The pre-curing procedure is: the room temperature is raised to 120°C within 1 hour, maintained for 30 minutes, and naturally cooled to below 60°C; the drying and curing procedure is: the room temperature is raised to 120°C within 1 hour; 120°C is kept for 0.5 hours, then raised to 180°C within 1 hour, 180°C is kept for 1.5 hours, and naturally cooled to below 60°C. Example 10

[0103] This embodiment provides an absorbing coating and an absorbing honeycomb, wherein the absorbing coating comprises the following raw materials, measured in parts by weight: 65 parts of the silicon-molybdenum co-modified epoxy resin of Example 3, 3 parts of a curing agent dicyandiamide, 10 parts of a filler carbon black, 5 parts of a dispersant BYK108, 1 part of a leveling agent BYK320, 2 parts of a defoaming agent 6800, 1 part of an accelerator, and 250 parts of a solvent toluene.

[0104] The preparation method of the microwave-absorbing honeycomb is as follows: the dust of the honeycomb core material is removed by an air sprayer, and the honeycomb core material is placed in a blast drying oven at 120°C for 1 hour. The honeycomb core material is immersed in the above-mentioned microwave-absorbing coating for multiple immersions, and each immersion is completely immersed for 5 minutes. After each immersion, it is hung to dry and pre-cured for 30 minutes before the next immersion, until the density of the honeycomb core material after immersion increases to 52kg / m 3 ; The honeycomb absorbing material that has been impregnated and aired for the last time is cured. The pre-curing procedure is: the room temperature is raised to 120°C within 1 hour, maintained for 30 minutes, and naturally cooled to below 60°C; the drying and curing procedure is: the room temperature is raised to 120°C within 1 hour; 120°C is kept for 0.5 hours, then raised to 180°C within 1 hour, 180°C is kept for 1.5 hours, and naturally cooled to below 60°C. Embodiment 11

[0105] This embodiment provides an absorbing coating and an absorbing honeycomb, wherein the absorbing coating comprises the following raw materials, measured in parts by weight: 60 parts of the silicon-molybdenum co-modified epoxy resin of Example 3, 5 parts of a curing agent dicyandiamide, 40 parts of a filler carbon black, 5 parts of a dispersant BYK108, 1 part of a leveling agent BYK320, 2 parts of a defoaming agent 6800, 1 part of an accelerator, and 250 parts of a solvent toluene.

[0106] The preparation method of the microwave-absorbing honeycomb is as follows: the dust of the honeycomb core material is removed by an air sprayer, and the honeycomb core material is placed in a blast drying oven at 120°C for 1 hour. The honeycomb core material is immersed in the above-mentioned microwave-absorbing coating for multiple immersions, and each immersion is completely immersed for 5 minutes. After each immersion, it is hung to dry and pre-cured for 30 minutes before the next immersion, until the density of the honeycomb core material after immersion increases to 52kg / m 3 ; The honeycomb absorbing material that has been impregnated and aired for the last time is cured. The pre-curing procedure is: the room temperature is raised to 120°C within 1 hour, maintained for 30 minutes, and naturally cooled to below 60°C; the drying and curing procedure is: the room temperature is raised to 120°C within 1 hour; 120°C is kept for 0.5 hours, then raised to 180°C within 1 hour, 180°C is kept for 1.5 hours, and naturally cooled to below 60°C. Example 12

[0107] This embodiment provides an absorbing coating and an absorbing honeycomb, wherein the absorbing coating comprises the following raw materials, measured in parts by weight: 70 parts of the silicon-molybdenum co-modified epoxy resin of Example 3, 5 parts of a curing agent dicyandiamide, 10 parts of a filler carbon black, 5 parts of a dispersant BYK108, 1 part of a leveling agent BYK320, 2 parts of a defoaming agent 6800, 1 part of an accelerator, and 250 parts of a solvent toluene.

[0108] The preparation method of the microwave-absorbing honeycomb is as follows: the dust of the honeycomb core material is removed by an air sprayer, and the honeycomb core material is placed in a blast drying oven at 120°C for 1 hour. The honeycomb core material is immersed in the above-mentioned microwave-absorbing coating for multiple immersions, and each immersion is completely immersed for 5 minutes. After each immersion, it is hung to dry and pre-cured for 30 minutes before the next immersion, until the density of the honeycomb core material after immersion increases to 52kg / m 3 ; The honeycomb absorbing material that has been impregnated and aired for the last time is cured. The pre-curing procedure is: the room temperature is raised to 120°C within 1 hour, maintained for 30 minutes, and naturally cooled to below 60°C; the drying and curing procedure is: the room temperature is raised to 120°C within 1 hour; 120°C is kept for 0.5 hours, then raised to 180°C within 1 hour, 180°C is kept for 1.5 hours, and naturally cooled to below 60°C. Embodiment 13

[0109] This embodiment provides an absorbing coating and an absorbing honeycomb, wherein the absorbing coating comprises the following raw materials, measured in parts by weight: 55 parts of the silicon-molybdenum co-modified epoxy resin of Example 3, 2.8 parts of a curing agent dicyandiamide, 30 parts of filler carbon black, 5 parts of a dispersant BYK108, 1 part of a leveling agent BYK320, 2 parts of a defoaming agent 6800, 1 part of an accelerator, and 250 parts of a solvent toluene.

[0110] The preparation method of the microwave-absorbing honeycomb is as follows: the dust of the honeycomb core material is removed by an air sprayer, and the honeycomb core material is placed in a blast drying oven at 120°C for 1 hour. The honeycomb core material is immersed in the above-mentioned microwave-absorbing coating for multiple immersions, and each immersion is completely immersed for 5 minutes. After each immersion, it is hung to dry and pre-cured for 30 minutes before the next immersion, until the density of the honeycomb core material after immersion increases to 52kg / m 3 ; The honeycomb absorbing material that has been impregnated and aired for the last time is cured. The pre-curing procedure is: the room temperature is raised to 120°C within 1 hour, maintained for 30 minutes, and naturally cooled to below 60°C; the drying and curing procedure is: the room temperature is raised to 120°C within 1 hour; 120°C is kept for 0.5 hours, then raised to 180°C within 1 hour, 180°C is kept for 1.5 hours, and naturally cooled to below 60°C. Embodiment 14

[0111] This embodiment provides an absorbing coating and an absorbing honeycomb, wherein the absorbing coating comprises the following raw materials, measured in parts by weight: 65 parts of the silicon-molybdenum co-modified epoxy resin of Example 3, 3.2 parts of a curing agent dicyandiamide, 20 parts of a filler carbon black, 5 parts of a dispersant BYK108, 1 part of a leveling agent BYK320, 2 parts of a defoaming agent 6800, 1 part of an accelerator, and 250 parts of a solvent toluene.

[0112] The preparation method of the microwave-absorbing honeycomb is as follows: the dust of the honeycomb core material is removed by an air sprayer, and the honeycomb core material is placed in a blast drying oven at 120°C for 1 hour. The honeycomb core material is immersed in the above-mentioned microwave-absorbing coating for multiple immersions, and each immersion is completely immersed for 5 minutes. After each immersion, it is hung to dry and pre-cured for 30 minutes before the next immersion, until the density of the honeycomb core material after immersion increases to 52kg / m 3 ; The honeycomb absorbing material that has been impregnated and aired for the last time is cured. The pre-curing procedure is: the room temperature is raised to 120°C within 1 hour, maintained for 30 minutes, and naturally cooled to below 60°C; the drying and curing procedure is: the room temperature is raised to 120°C within 1 hour; 120°C is kept for 0.5 hours, then raised to 180°C within 1 hour, 180°C is kept for 1.5 hours, and naturally cooled to below 60°C. Embodiment 15

[0113] The present embodiment provides an absorbing coating and an absorbing honeycomb, wherein the absorbing coating comprises the following raw materials, measured in parts by weight: 75 parts of the silicon-molybdenum co-modified epoxy resin of Example 3, 3.6 parts of a curing agent dicyandiamide, 10 parts of a filler carbon black, 5 parts of a dispersant BYK108, 1 part of a leveling agent BYK320, 2 parts of a defoaming agent 6800, 1 part of an accelerator, and 250 parts of a solvent toluene.

[0114] The preparation method of the microwave-absorbing honeycomb is as follows: the dust of the honeycomb core material is removed by an air sprayer, and the honeycomb core material is placed in a blast drying oven at 120°C for 1 hour. The honeycomb core material is immersed in the above-mentioned microwave-absorbing coating for multiple immersions, and each immersion is completely immersed for 5 minutes. After each immersion, it is hung to dry and pre-cured for 30 minutes before the next immersion, until the density of the honeycomb core material after immersion increases to 52kg / m 3 ; The honeycomb absorbing material that has been impregnated and aired for the last time is cured. The pre-curing procedure is: the room temperature is raised to 120°C within 1 hour, maintained for 30 minutes, and naturally cooled to below 60°C; the drying and curing procedure is: the room temperature is raised to 120°C within 1 hour; 120°C is kept for 0.5 hours, then raised to 180°C within 1 hour, 180°C is kept for 1.5 hours, and naturally cooled to below 60°C. Comparative Example 1

[0115] This comparative example provides a silicon-modified epoxy resin, and the preparation method thereof is as follows.

[0116] 100g of hydrogen-terminated silicone oil, 1g of polymerization inhibitor p-hydroxyanisole and 10g of 1% by mass chloroplatinic acid in tetrahydrofuran were added to a 1000ml four-necked flask equipped with a stirrer, a dropping funnel, a thermometer and a reflux condenser, and the above substances were heated to 80°C under stirring. At this temperature, 30g of allyl glycidyl ether was added dropwise with a separating funnel within a certain period of time, and the reaction was continued with stirring for 30 minutes.

[0117] The comparative example provides an absorbing coating and an absorbing honeycomb, wherein the absorbing coating comprises the following raw materials, measured in parts by weight: 75 parts of silicon-modified epoxy resin, 3.6 parts of curing agent dicyandiamide, 10 parts of filler carbon black, 5 parts of dispersant BYK108, 1 part of leveling agent BYK320, 2 parts of defoaming agent 6800, 1 part of accelerator and 250 parts of solvent toluene.

[0118] The preparation method of the microwave-absorbing honeycomb is as follows: the dust of the honeycomb core material is removed by an air sprayer, and the honeycomb core material is placed in a blast drying oven at 120°C for 1 hour. The honeycomb core material is immersed in the above-mentioned microwave-absorbing coating for multiple immersions, and each immersion is completely immersed for 5 minutes. After each immersion, it is hung to dry and pre-cured for 30 minutes before the next immersion, until the density of the honeycomb core material after immersion increases to 52kg / m 3; The honeycomb absorbing material that has been impregnated and aired for the last time is cured. The pre-curing procedure is: the room temperature is raised to 120°C within 1 hour, maintained for 30 minutes, and naturally cooled to below 60°C; the drying and curing procedure is: the room temperature is raised to 120°C within 1 hour; 120°C is kept for 0.5 hours, then raised to 180°C within 1 hour, 180°C is kept for 1.5 hours, and naturally cooled to below 60°C. Comparative Example 2

[0119] This comparative example provides a molybdenum-modified epoxy resin, and its preparation method is as follows.

[0120] 100g of epoxy resin (Sinopec Epoxy Resin E-51 Baling Plant CYD-128 Epoxy Resin) and 300g of tetrahydrofuran were stirred and reacted for 30 minutes. After that, 20g of a mixed solution of ammonium molybdate and dilute hydrochloric acid was added. The mass ratio of ammonium molybdate, HCl and distilled water in the mixed solution was 196:73:1960. At the end of the reaction, the reaction mixture was distilled under reduced pressure to remove volatile products.

[0121] This comparative example also provides an absorbing coating and an absorbing honeycomb, wherein the absorbing coating comprises the following raw materials, in parts by weight: 75 parts of molybdenum-modified epoxy resin, 3.6 parts of curing agent dicyandiamide, 10 parts of filler carbon black, 5 parts of dispersant BYK108, 1 part of leveling agent BYK320, 2 parts of defoaming agent 6800, 1 part of accelerator and 250 parts of solvent toluene.

[0122] The preparation method of the microwave-absorbing honeycomb is as follows: the dust of the honeycomb core material is removed by an air sprayer, and the honeycomb core material is placed in a blast drying oven at 120°C for 1 hour. The honeycomb core material is immersed in the above-mentioned microwave-absorbing coating for multiple immersions, and each immersion is completely immersed for 5 minutes. After each immersion, it is hung to dry and pre-cured for 30 minutes before the next immersion, until the density of the honeycomb core material after immersion increases to 52kg / m 3 ; The honeycomb absorbing material that has been impregnated and aired for the last time is cured. The pre-curing procedure is: the room temperature is raised to 120°C within 1 hour, maintained for 30 minutes, and naturally cooled to below 60°C; the drying and curing procedure is: the room temperature is raised to 120°C within 1 hour; 120°C is kept for 0.5 hours, then raised to 180°C within 1 hour, 180°C is kept for 1.5 hours, and naturally cooled to below 60°C. Comparative Example 3

[0123] The comparative example provides an absorbing coating and an absorbing honeycomb, wherein the absorbing coating comprises the following raw materials, measured in parts by weight: 75 parts of epoxy resin (Sinopec epoxy resin E-51 Baling plant CYD-128 epoxy resin), 3.6 parts of curing agent dicyandiamide, 10 parts of filler carbon black, 5 parts of dispersant BYK108, 1 part of leveling agent BYK320, 2 parts of defoaming agent 6800, 1 part of accelerator and 250 parts of solvent toluene.

[0124] The preparation method of the microwave-absorbing honeycomb is as follows: the dust of the honeycomb core material is removed by an air sprayer, and the honeycomb core material is placed in a blast drying oven at 120°C for 1 hour. The honeycomb core material is immersed in the above-mentioned microwave-absorbing coating for multiple immersions, and each immersion is completely immersed for 5 minutes. After each immersion, it is hung to dry and pre-cured for 30 minutes before the next immersion, until the density of the honeycomb core material after immersion increases to 52kg / m 3 ; The honeycomb absorbing material that has been impregnated and air-dried for the last time is cured. The pre-curing procedure is: the room temperature is raised to 120°C within 1 hour, maintained for 30 minutes, and naturally cooled to below 60°C; the drying and curing procedure is: the room temperature is raised to 120°C within 1 hour; 120°C is kept for 0.5 hours, then raised to 180°C within 1 hour, 180°C is kept for 1.5 hours, and naturally cooled to below 60°C. Test method and result analysis

[0125] According to the test method ASTM C 365M-05, the compressive strength and modulus of the stabilized absorbing honeycomb at room temperature were tested. The standard size of the sample is 50mm (L) * 50mm (W) * 12.7mm (T). The skin of the stabilized absorbing honeycomb compression sample is 0.5mm thick 2024-T3 aluminum sheet, and the selected film is J-116A (0.2mm thick). According to the test method ASTM C 365, the compressive strength of the absorbing honeycomb was tested at 175℃ and kept warm for 15 minutes. According to the test method ASTM C 365, the compressive strength of the absorbing honeycomb sample was tested in 23℃ water and soaked for 24 hours.

[0126] The L-direction and W-direction shear strength and modulus of the absorbing honeycomb at room temperature were tested according to the test method ASTM C 273. The standard size of the specimen is as follows: L-direction shear is 150 mm (L) * 50 mm (W) * 12.7 mm (T); W-direction shear is 150 mm (W) * 50 mm (L) * 12.7 mm (T). J-116A (0.2 mm thick) film was used for specimen preparation. The L-direction shear strength of the absorbing honeycomb was tested at 150°C and kept warm for 15 minutes according to the test method ASTM C 365.

[0127] Wave absorbing performance test method: GB / T 35679 Electromagnetic parameter test method of solid material using waveguide device in microwave frequency band and GJB 2038 Test method for reflectivity of radar absorbing material.

[0128] Table 1 Conversion rate of silicon-molybdenum co-modified epoxy resin synthesized in Examples 1 to 6

[0129]

[0130] Table 2 Compressive strength and modulus test of the microwave-absorbing honeycomb at room temperature of Examples 7 to 15

[0131]

[0132]

[0133] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0134] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A silicon-molybdenum co-modified epoxy resin, characterized in that: Its structural formula is shown in Formula I: I； wherein n and m are each independently selected from integers of 1 to 10, R5 and R6 are each independently selected from -H, a C1-C4 substituted or unsubstituted straight-chain alkyl group, or a C1-C4 substituted or unsubstituted branched-chain alkyl group.

2. A method for preparing the silicon-molybdenum co-modified epoxy resin as claimed in claim 1, characterized in that: The steps include: S11: preparing a first mixed solution, wherein the first mixed solution comprises terminal hydrogen silicone oil, a catalyst, an inhibitor and a first solvent; S12: heating the first mixed solution to 70° C. to 90° C., adding glycidyl ether containing a carbon-carbon double bond, and reacting for 20 min to 40 min to obtain a first reactant, wherein the glycidyl ether containing a carbon-carbon double bond has the following structural formula: , wherein R5 and R6 are each independently selected from -H, C1~C4 substituted or unsubstituted straight-chain alkyl, or C1~C4 substituted or unsubstituted branched-chain alkyl; S13: preparing a second mixed solution, wherein the second mixed solution comprises the first reactant, a strong inorganic acid, a second solvent and ammonium molybdate, reacting for 30 minutes to 60 minutes to obtain a second reactant, and removing volatile substances from the second reactant.

3. The preparation method of silicon-molybdenum co-modified epoxy resin as claimed in claim 2, characterized in that, In step S11, in parts by weight, the first mixed solution contains 20 to 30 parts of the terminal hydrogenated silicone oil, 2 to 3 parts of the catalyst, 0.2 to 0.3 parts of the inhibitor and 200 to 300 parts of the first solvent, wherein the first solvent is tetrahydrofuran, the catalyst is chloroplatinic acid, the inhibitor is p-hydroxyanisole, and the relative molecular mass of the terminal hydrogenated silicone oil is 500 to 600.

4. The method for preparing a silicon-molybdenum co-modified epoxy resin as claimed in claim 2 or 3, wherein: In step S13, the second mixed solution is prepared from the following raw materials in parts by weight: 50 to 80 parts of the first reactant, 1 to 2 parts of ammonium molybdate, 1 to 2 parts of an inorganic strong acid, and 50 to 60 parts of the second solvent, wherein the second solvent comprises tetrahydrofuran and deionized water in a mass ratio of 1:

1.

5. A radar absorbing coating, characterized in that: The invention is prepared from the following raw materials in parts by weight: 50 to 90 parts of the silicon-molybdenum co-modified epoxy resin as claimed in claim 1, 3 to 10 parts of a curing agent, 10 to 40 parts of a filler, 3 to 7 parts of a dispersant, 0.5 to 2 parts of a leveling agent, 0.8 to 1.2 parts of an accelerator and 1 to 3 parts of a defoaming agent.

6. The radar absorbing coating according to claim 5, characterized in that: The curing agent is selected from at least one of anhydride latent curing agents, dicyandiamide latent curing agents and imidazole latent curing agents, and the latent period of the curing agent is more than one month; and / or The filler is selected from at least one of graphene, carbon nanotubes, conductive graphite and carbon black; and / or The dispersant is selected from at least one of BYK108 and 904S; and / or The leveling agent is selected from at least one of BYK320, BYK333 and BYK358N; and / or The accelerator is triphenylphosphine; and / or The defoamer is a silicone defoamer.

7. A method for preparing a microwave-absorbing honeycomb, characterized in that: The following steps are involved: S21: preparing materials according to the raw material formula of the radar absorbing coating as claimed in claim 5 or 6; S22: drying the honeycomb core material, and immersing the dried honeycomb core material in the radar absorbing coating; S23: drying the impregnated honeycomb core material to obtain an impregnated honeycomb core material, and drying and curing the impregnated honeycomb core material.

8. The method for preparing the wave-absorbing honeycomb according to claim 7, characterized in that: In step S22, the honeycomb core material is dried at 100° C. to 140° C. for 1 h to 2 h, and the dried honeycomb core material is immersed in the radar absorbing coating by completely immersing the honeycomb core material for 5 min to 10 min; and / or In step S23, drying and curing the impregnated honeycomb core material includes a pre-curing step and a secondary drying and curing step, wherein the pre-curing step includes heating the impregnated honeycomb core material to 100°C~140°C, maintaining for 25min~35min, and then cooling to 40°C~80°C to obtain the pre-cured impregnated honeycomb core material; the secondary drying and curing step includes heating the pre-cured impregnated honeycomb core material to 100°C~140°C, maintaining for 25min~35min, then heating to 160°C~200°C, maintaining for 1h~2h, and then cooling to 40°C~80°C.

9. A microwave absorbing honeycomb, characterized in that: The method for preparing the wave-absorbing honeycomb as claimed in claim 7 or 8 is used for preparing the wave-absorbing honeycomb.

10. Use of the wave-absorbing honeycomb according to claim 9 in preparing a thermal radiation detector, a thermal radiation imager or a non-destructive detector.

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