A zero-VOC water-based thermally conductive insulating resin composition and preparation method thereof

Abstract

The present invention relates to a zero-VOC water-based thermally conductive insulating resin composition and a preparation method thereof, which is composed of the following raw materials in parts by mass: 40-50 parts of water-based epoxy resin, 2-4 parts of aniline curing agent, 1-3 parts of dispersant, 35-50 parts of thermally conductive filler, 0.1-0.3 parts of defoamer, and 3-5 parts of modified carbon black. Among them, after the carbon black surface is grafted with alkyl, its compatibility with epoxy resin is improved, reducing its agglomeration and uneven dispersion phenomenon, thereby improving the thermal conductivity and insulation performance of the composite material; on the other hand, the present invention adopts water-based epoxy resin and aniline curing agent, in which carbon black plays the role of solid filler, so that the resin solid content is relatively high, and does not contain diluent, relative to the traditional organic solvent-containing epoxy resin, it has a zero-VOC environmental protection effect. The present invention takes into account the balance of thermal conductivity, insulation and environmental protection in epoxy resin materials, and has good application prospects.

Description

Technical Field

[0001] The present invention relates to the technical field of epoxy resins, and in particular to a zero-VOC water-based thermally conductive insulating resin composition and a preparation method thereof. Background Art

[0002] At present, in the field of organic coatings, epoxy resin is widely used in the electronics and electrical industries due to its good bonding properties, super hardness of the cured film and small curing shrinkage. Epoxy resin is mainly used in electrical components such as motor coils or transformers to fill gaps and make them a sealed whole after curing, thereby improving their insulation performance, mechanical properties and weather resistance. Existing water-based epoxy insulating paints generally need to add additives, emulsifiers, or introduce acrylic acid and acrylate monomers to make a water-based system, so the insulation performance may be reduced, and it has a high content of volatile organic compounds (VOC). VOC has a huge impact on human health. When the VOC in the air reaches a certain concentration, people will feel headaches, nausea, vomiting, and fatigue in a short time. In severe cases, it may also damage the liver, kidneys, brain and nervous system, causing serious consequences such as memory loss.

[0003] Moreover, with the improvement of the integration of electrical components, the power density has greatly increased, and the heat dissipation problem must also be paid attention to. For example, the heat generated by high-power semiconductor devices during operation will cause the chip temperature to rise. If there is no appropriate heat dissipation measure, the device operating temperature will exceed the maximum allowable temperature, which will cause the performance to deteriorate or even damage. Studies have shown that for every 10°C increase in the temperature of a semiconductor chip, the chip reliability will be reduced by half. In general, the higher the operating temperature of the device, the shorter the life cycle of the device. Therefore, reducing the device temperature is one of the effective ways to extend its life cycle. Materials with high thermal conductivity are also extremely important for the stability of electrical equipment. However, prior art, such as CN105295658B, discloses a water-based insulating varnish and a preparation method thereof, which has certain insulating properties, but its thermal conductivity may be poor. At present, there are few reports on environmentally friendly resin coatings that take into account both thermal conductivity and insulation.

[0004] In summary, the prior art has not reported how to balance the thermal conductivity, insulation and other properties of epoxy resin materials. Therefore, it is urgent to develop a new technical solution to solve the problems existing in the prior art. Summary of the invention

[0005] Based on this, the present invention has developed a zero-VOC water-based thermally conductive insulating resin composition and a preparation method thereof, which is compounded by modified carbon black and a specific resin so that the material has good thermal conductivity and insulation properties, does not contain VOC, has environmental protection effects, and has good application prospects.

[0006] One object of the present invention is to provide a zero-VOC water-based thermally conductive insulating resin composition, wherein the zero-VOC water-based thermally conductive insulating resin composition is prepared from the following raw materials in parts by weight:

[0007]

[0008]

[0009] Wherein, the aniline curing agent includes a diamine derivative having a functional group of 2;

[0010] The modified carbon black is a mixture of alkylated carbon black and carbon black.

[0011] Furthermore, the amine derivative with a functional group of 2 is selected from one or more of meta-phenylenediamine and diethyltoluenediamine.

[0012] Furthermore, the aniline curing agent also includes N,N″-(methyl-1,3-phenylene)bis(N′,N′-dimethyl)urea.

[0013] Furthermore, the water-based epoxy resin is selected from one or more of bisphenol A epoxy resin, bisphenol F epoxy resin, and bisphenol S epoxy resin.

[0014] Furthermore, the defoaming agent is selected from the BYK brand of defoaming agent.

[0015] Furthermore, the dispersant is selected from anionic surfactants or nonionic surfactants.

[0016] Furthermore, in the aniline curing agent, the mass ratio of the diamine derivative with a functional group of 2 to N,N″-(methyl-1,3-phenylene)bis(N',N'-dimethyl)urea is 0.2-0.5:2.

[0017] Furthermore, the thermally conductive filler is selected from one or more of silicon powder, aluminum oxide, and boron nitride.

[0018] Another object of the present invention is to provide a method for preparing a zero-VOC water-based thermally conductive insulating resin composition, characterized in that the method for preparing the zero-VOC water-based thermally conductive insulating resin composition comprises the following steps:

[0019] S1, soaking carbon black in a solution of an alkyl acid, ultrasonically heating the carbon black for reaction, washing the carbon black to obtain the alkylated carbon black, and blending the carbon black with the carbon black to obtain the modified carbon black;

[0020] S2. After drying the waterborne epoxy resin, put it into a reaction kettle, maintain the material temperature at 60-65°C, the vacuum degree at -0.08~-0.09MPa, and stir for 1-2h;

[0021] S3. Add aniline curing agent, dispersant, thermal conductive filler, defoaming agent and modified carbon black, cool the system to below 10°C, stir for 0.5-1h, and discharge after standing.

[0022] Furthermore, the heating temperature is 60-70°C.

[0023] Another object of the present invention is to provide the use of the zero-VOC aqueous thermally conductive insulating resin composition in microwave oven transformers and motor impregnation insulation.

[0024] The present invention has the following beneficial effects:

[0025] The present invention discloses a zero-VOC water-based thermally conductive insulating resin composition and a preparation method thereof, which is obtained by modifying carbon black by alkylation and then blending it with epoxy resin and aniline curing agent. Inorganic carbon black has poor compatibility with resin materials. The present invention improves the lipophilicity after grafting alkyl groups on its surface, improves the compatibility with components such as organic resins, and reduces the agglomeration and uneven dispersion of modified carbon black, thereby improving the thermal conductivity and insulation performance of the composite material. On the other hand, the present invention adopts a water-based epoxy resin and aniline curing agent system, in which carbon black plays the role of a solid filler, so that the resin solid content is relatively high, and does not contain diluents and organic solvents, has a zero-VOC environmental protection effect, and has good application prospects. DETAILED DESCRIPTION

[0026] In order to more clearly illustrate the technical solution of the present invention, the following examples are listed. Unless otherwise stated, the raw materials, reactions and post-treatment methods shown in the examples are common raw materials on the market and technical methods well known to those skilled in the art.

[0027] The words "preferred", "preferably", "more preferably", etc. in the present invention refer to embodiments of the present invention that can provide certain beneficial effects in certain circumstances. However, other embodiments may also be preferred under the same circumstances or other circumstances. In addition, the description of one or more preferred embodiments does not imply that other embodiments are not applicable, nor is it intended to exclude other embodiments from the scope of the present invention.

[0028] It should be understood that, except in any operating examples, or where otherwise indicated, all numbers indicating, for example, the amounts of ingredients used in the specification and claims should be understood to be modified in all cases by the term "about". Therefore, unless indicated to the contrary, the numerical parameters set forth in the following specification and the appended claims are approximate values ​​that vary depending on the desired properties to be obtained by the present invention.

[0029] In the examples and comparative examples, the following materials were used and had the functions indicated.

[0030] The carbon black is ORION SPECIAL BLACK 4A high resistance insulating carbon black, purchased from Anhui Jingzhicai New Materials.

[0031] The alkyl acid was dodecanoic acid, which was purchased from Shandong Jinghao Chemical.

[0032] The water-based epoxy resin is NPEL-128 bisphenol A epoxy resin, purchased from Wanqing Chemical.

[0033] Aniline curing agent, which is a mixture of m-phenylenediamine and N,N"-(methyl-1,3-phenylene)bis(N',N'-dimethyl)urea in a mass ratio of 1:4.

[0034] The dispersant is fatty alcohol polyoxyethylene ether AED-9, which was purchased from Jinan Yihao Chemical.

[0035] The thermal conductive filler is alumina with an average particle size of about 30-100μm, purchased from Zibo Yishengjia Aluminum.

[0036] The defoaming agent is BYK-1880, which was purchased from Guangzhou Situyuan Chemical.

[0037] Diethylenetriamine was purchased from Shandong Hongyunchang Chemical.

[0038] The parts involved in the present invention all refer to parts by mass.

[0039] Example 1

[0040] A method for preparing a zero-VOC water-based thermally conductive insulating resin composition, which is prepared from the following raw materials in parts by weight:

[0041]

[0042]

[0043] The method for preparing the zero-VOC water-based thermally conductive insulating resin composition comprises the following steps:

[0044] S1. Take 1.5 parts of carbon black and soak them in excess dodecanoic acid, ultrasonically heat them to 65° C. for reaction for 1 hour, wash them, and dry them at 40° C. for 4 hours to obtain alkylated carbon black, and blend the alkylated carbon black with the remaining carbon black (m:m=1:1) to obtain the modified carbon black;

[0045] S2. Put the waterborne epoxy resin into an oven, dry it at 55°C for 8h, put it into a reactor, keep the material temperature at 65°C, the vacuum degree at -0.08MPa, and stir for 1h;

[0046] S3. Add aniline curing agent, dispersant, thermal conductive filler, defoaming agent and modified carbon black according to the above mass fractions, cool the system to below 10°C, stir the reaction for 0.5h, and discharge the material after standing.

[0047] Example 2

[0048] A method for preparing a zero-VOC water-based thermally conductive insulating resin composition, which is prepared from the following raw materials in parts by weight:

[0049]

[0050] The method for preparing the zero-VOC water-based thermally conductive insulating resin composition comprises the following steps:

[0051] S1. Take 2.5 parts of carbon black and soak them in excess dodecanoic acid, ultrasonically heat them to 65° C. for reaction for 1 hour, wash them, and dry them at 40° C. for 4 hours to obtain alkylated carbon black, and blend the alkylated carbon black with the remaining carbon black (m:m=1:1) to obtain the modified carbon black;

[0052] S2. Put the waterborne epoxy resin into an oven, dry it at 55°C for 8h, put it into a reactor, keep the material temperature at 65°C, the vacuum degree at -0.08MPa, and stir for 1h;

[0053] S3. Add aniline curing agent, dispersant, thermal conductive filler, defoaming agent and modified carbon black according to the above mass fractions, cool the system to below 10°C, stir the reaction for 0.5h, and discharge the material after standing.

[0054] Example 3

[0055] A method for preparing a zero-VOC water-based thermally conductive insulating resin composition, which is prepared from the following raw materials in parts by weight:

[0056]

[0057] The method for preparing the zero-VOC water-based thermally conductive insulating resin composition comprises the following steps:

[0058] S1. Take 2 parts of carbon black and soak them in excess dodecanoic acid, ultrasonically heat them to 65° C. for reaction for 1 hour, wash them, and dry them at 40° C. for 4 hours to obtain alkylated carbon black, and blend the alkylated carbon black with the remaining carbon black (m:m=1:1) to obtain the modified carbon black;

[0059] S2. Put the waterborne epoxy resin into an oven, dry it at 55°C for 8h, put it into a reactor, keep the material temperature at 65°C, the vacuum degree at -0.08MPa, and stir for 1h;

[0060] S3. Add aniline curing agent, dispersant, thermal conductive filler, defoaming agent and modified carbon black according to the above mass fractions, cool the system to below 10°C, stir the reaction for 0.5h, and discharge the material after standing.

[0061] Comparative Example 1

[0062] The raw materials, raw material portions and preparation methods used in Comparative Example 1 are the same as those in Example 1, with the only difference being that in Comparative Example 1, the modified carbon black is replaced with an equal mass portion of unmodified insulating carbon black.

[0063] Comparative Example 2

[0064] The raw materials, raw material parts and preparation method used in Comparative Example 2 are the same as those in Example 1, with the only difference being that in Comparative Example 2, the aniline curing agent is replaced with an equal mass part of diethylenetriamine.

[0065] Test Case

[0066] Test method:

[0067] The thermal conductivity, volume resistivity, VOC and tensile strength of the thermally conductive insulating resin composition samples prepared in Examples 1-3 and Comparative Examples 1-2 were tested in accordance with standards such as GB / T 1410-2006 Test method for volume resistivity and surface resistivity of solid insulating materials.

[0068] The test results are shown in Table 1.

[0069] Table 1 Performance test results

[0070]

[0071]

[0072] According to Table 1, it can be concluded that the zero-VOC water-based thermally conductive insulating resin compositions prepared in Examples 1-3 of the present invention have excellent tensile strength, thermal conductivity, and volume resistivity, and their performance is significantly better than that of the comparative examples. Since the modified carbon black is replaced by unmodified ordinary carbon black in Comparative Example 1, its compatibility with the resin is poor, and there are agglomeration and uneven dispersion phenomena, which affect the mechanical properties, thermal conductivity and volume resistivity of the resin composition. In Comparative Example 2, since the aniline curing agent is replaced by a low-boiling point fatty amine curing agent, the volatile organic matter increases during the curing process, resulting in its VOC content being higher than that of the other test examples.

[0073] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be considered exemplary and non-restrictive in all respects, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention.

[0074] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A zero-VOC water-based thermally conductive insulating resin composition, characterized in that: The zero-VOC water-based thermally conductive insulating resin composition is prepared from the following raw materials in parts by mass: Wherein, the aniline curing agent includes a diamine derivative having a functional group of 2; The modified carbon black is a mixture of alkylated carbon black and carbon black; The water-based epoxy resin is selected from one or more of bisphenol A epoxy resin, bisphenol F epoxy resin, and bisphenol S epoxy resin; In the aniline curing agent, the mass ratio of the diamine derivative with a functional group of 2 to N,N″-(methyl-1,3-phenylene)bis(N',N'-dimethyl)urea is 0.2-0.5:2; The alkylated carbon black is blended with the remaining carbon black in a mass ratio of 1:

1.

2. The zero-VOC aqueous thermally conductive insulating resin composition according to claim 1, characterized in that: The amine derivative with a functional group of 2 is selected from one or more of meta-phenylenediamine and diethyltoluenediamine.

3. The zero-VOC aqueous thermally conductive insulating resin composition according to claim 1, characterized in that: The aniline curing agent also includes N,N″-(methyl-1,3-phenylene)bis(N′,N′-dimethyl)urea.

4. The zero-VOC aqueous thermally conductive insulating resin composition according to claim 1, characterized in that: The defoamer is selected from the defoamers of BYK brands.

5. The zero-VOC aqueous thermally conductive insulating resin composition according to claim 1, characterized in that: The dispersant is selected from anionic surfactants or nonionic surfactants.

6. The method for preparing the zero-VOC water-based thermally conductive insulating resin composition according to any one of claims 1 to 5, characterized in that: The preparation method of the zero-VOC water-based thermally conductive insulating resin composition comprises the following steps: S1, soaking carbon black in a solution of an alkyl acid, ultrasonically heating the carbon black for reaction, washing the carbon black to obtain the alkylated carbon black, and blending the carbon black with the carbon black to obtain the modified carbon black; S2. After drying the waterborne epoxy resin, put it into a reaction kettle, maintain the material temperature at 60-65°C, the vacuum degree at -0.08~-0.09MPa, and stir for 1-2h; S3. Add aniline curing agent, dispersant, thermal conductive filler, defoaming agent and modified carbon black, cool the system to below 10°C, stir for 0.5-1h, and discharge after standing.

7. The method for preparing the zero-VOC water-based thermally conductive insulating resin composition according to claim 6, characterized in that: In step S1, the heating temperature is 60-70°C.

8. Use of the zero-VOC water-based thermally conductive insulating resin composition according to any one of claims 1 to 5 in microwave oven transformer and motor impregnation insulation.

Images