CN112210181A - Temperature reaction type capacitor packaging material and preparation method thereof - Google Patents
Temperature reaction type capacitor packaging material and preparation method thereof Download PDFInfo
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- CN112210181A CN112210181A CN202011020719.3A CN202011020719A CN112210181A CN 112210181 A CN112210181 A CN 112210181A CN 202011020719 A CN202011020719 A CN 202011020719A CN 112210181 A CN112210181 A CN 112210181A
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L51/00—Compositions of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
- C08K3/24—Acids; Salts thereof
- C08K3/26—Carbonates; Bicarbonates
- C08K2003/265—Calcium, strontium or barium carbonate
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2203/00—Applications
- C08L2203/20—Applications use in electrical or conductive gadgets
- C08L2203/206—Applications use in electrical or conductive gadgets use in coating or encapsulating of electronic parts
Abstract
The invention discloses a temperature reaction type capacitor packaging material and a preparation method thereof. The packaging material is prepared from epoxidized soybean oil and unsaturated resin, wherein the epoxidized soybean oil is filled in the unsaturated resin after the unsaturated resin forms a cross-linked network structure through free radical polymerization reaction to form oily gel. The gel has no fluidity at normal temperature, and can recover the state of flowing liquid at the temperature higher than 100 ℃, thereby facilitating heat dissipation. The oily gel is used for capacitor packaging, has long service life, has no leakage risk in the processes of processing, production, transportation and maintenance, and can solve the problems that liquid oily packaging materials are easy to leak and the like.
Description
Technical Field
The invention relates to the technical field of capacitors, in particular to a packaging material prepared by polymerizing epoxidized soybean oil and unsaturated resin serving as main raw materials and a preparation method thereof.
Background
The electronic industry in China is rapidly developed, the demand of the capacitor is continuously increased, and the specification is diversified. Insulating encapsulants for capacitors are diverse, with liquid greases and cured epoxy resins accounting for the majority of the proportion. Epoxy resins are low in market competitiveness due to high production costs, low in heat transfer efficiency of cured resins, low in potting efficiency, and prone to generate bubbles during potting (see, for example, patent document 1). Although the liquid grease has low price, easy canning, good fluidity and heat transfer performance, the liquid grease has the problems of easy exudation, easy aging, poor safety and the like. The research and development of the novel packaging material can not only develop wider markets, but also play a positive promoting role in the capacitor industry.
In recent years, with the increasing awareness of environmental protection and the increasing restrictions on VOC and HAP in coatings by governments, there has been an increasing call for the development of low-toxicity, environmentally friendly resin curing agents. The soybean oil has great yield and low cost, and the epoxidized soybean oil obtained by oxidation treatment can solve the problem that the soybean oil is easy to age and deteriorate. At present, the epoxidized soybean oil is simple in production process, can realize large-scale production, and is stable in product quality and low in price.
Because the epoxy group of the epoxidized soybean oil has poor reactivity, most of the existing methods for curing the epoxidized soybean oil need high-temperature conditions or long curing time, and some curing methods need curing agents with strong corrosivity, so that the conductive layer of the capacitor is easily damaged due to the defects of the curing methods.
Disclosure of Invention
In order to solve the technical problems in the prior art, the invention provides the packaging material based on the epoxidized soybean oil, which is kept in a solid state at normal temperature and normal working temperature, does not leak, and keeps better insulation and heat transfer effects, and when the temperature of a capacitor is abnormally increased, the capacitor is recovered to be liquid, so that the heat dissipation efficiency is improved. Specifically, the technical problem to be solved by the present invention is to provide a temperature-responsive capacitor packaging material, which is in an oily gel state at a temperature below 100 ℃, maintains good insulation and heat transfer effects, and is recovered to a liquid state at a temperature above 100 ℃, thereby improving heat dissipation efficiency.
The purpose of the invention is realized by the following technical scheme: a lipophilic cross-linked network is formed through the curing reaction of the unsaturated resin, and the epoxy soybean oil molecules are dispersed in the network to form oily gel, so that the curing of the epoxy soybean oil is realized. In order to ensure temperature reactivity, good processability and short-time curing capability at normal temperature, the epoxy soybean oil-based packaging material at least comprises the following components in parts by weight: an agent A: 15-200 parts of epoxidized soybean oil, 1-10 parts of dibenzoyl peroxide and a solvent thereof; and (2) agent B: 100 portions of commercial unsaturated resin, 4 to 30 portions of butyl acrylate, 0.2 to 2 portions of catalyst and 0.02 to 0.2 portion of filler.
As one of the preferable technical proposal, the solvent comprises but is not limited to one or more of ketone solvent, ester solvent and benzene solvent.
Further preferably, the solvent is acetone or methyl phthalate, wherein the minimum ratio to dibenzoyl peroxide is 30: 1 and 6: 1.
as one of the preferable technical proposal, the catalyst comprises but is not limited to one or more of N 'N-dimethylbenzylamine, N' N-dimethylaniline and triethanolamine.
The preparation method of the temperature reaction type capacitor packaging material comprises the following steps:
(1) epoxidized soybean oil is stirred and dewatered in a reaction kettle at 80 ℃ under reduced pressure. Dibenzoyl peroxide was mixed with acetone/methyl phthalate in a ratio of 1: 30 or 1: 6, mixing uniformly, and mixing with epoxidized soybean oil according to a certain proportion to prepare the component A.
(2) The component B is prepared by mixing commercially available unsaturated resin, butyl acrylate, catalyst and filler according to a proper proportion.
(3) And uniformly mixing the component A and the component B in a proper proportion, filling the mixture into a cavity of a capacitor, standing the mixture at room temperature for finishing the polymerization reaction, and finishing the curing, molding and processing of the grease.
The invention has the beneficial effects that:
(1) can be cured at room temperature, has no volatility, and has short curing reaction time.
(2) The epoxy soybean oil has good curing effect, no fluidity and no liquid at 100 ℃, and is converted into flowing liquid at the temperature higher than 100 ℃.
(3) The performance of the capacitor can be effectively improved, and the service life of the capacitor can be effectively prolonged.
Detailed Description
To make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the following description of the principles and features of the embodiments of the present invention is given by way of example only, and is not intended to limit the scope of the present invention.
Example 1
A preparation method of a temperature reaction type capacitor packaging material comprises the following specific steps:
(1) dibenzoyl peroxide and acetone in a ratio of 1: mixing at a ratio of 30 to obtain component A.
(2) 100 parts of commercially available unsaturated resin, 20 parts of butyl acrylate, 1.6 parts of N' N-dimethylbenzylamine and 0.1 part of gas-phase silicon dioxide and calcium carbonate respectively are uniformly mixed to prepare the component B.
(3) The component A and the component B are mixed according to the weight ratio of 1: 15, uniformly mixing, pouring into a cavity of the capacitor, standing at normal temperature for 13 minutes, and curing and molding.
Example 2
A preparation method of a temperature reaction type capacitor packaging material comprises the following specific steps:
(1) epoxidized soybean oil is stirred and dewatered for 8 hours in a reaction kettle at 80 ℃ under the reduced pressure condition. Dibenzoyl peroxide and methyl phthalate in a ratio of 1: 6 portions are mixed evenly, and then 100 portions of epoxidized soybean oil and 8 portions of dibenzoyl peroxide which is dissolved are taken to be stirred and mixed evenly to form the component A.
(2) 100 parts of commercially available unsaturated resin, 20 parts of butyl acrylate, 1.6 parts of N' N-dimethylbenzylamine and 0.1 part of fumed silica and calcium carbonate are sequentially and uniformly mixed to prepare the component B.
(3) And directly and uniformly mixing the component A and the component B, pouring the mixture into a cavity of a capacitor, standing at normal temperature for 17 minutes, and curing and molding.
Example 3
A preparation method of a temperature reaction type capacitor packaging material comprises the following specific steps:
(1) epoxidized soybean oil is stirred and dewatered for 8 hours in a reaction kettle at 80 ℃ under the reduced pressure condition. Dibenzoyl peroxide and methyl phthalate in a ratio of 1: 6 portions are mixed evenly, 333 portions of epoxidized soybean oil and 8 portions of dibenzoyl peroxide which is dissolved are taken to be stirred and mixed evenly to form the component A.
(2) 100 parts of commercially available unsaturated resin, 20 parts of butyl acrylate, 1.6 parts of N' N-dimethylbenzylamine and 0.1 part of fumed silica and calcium carbonate are sequentially and uniformly mixed to prepare the component B.
(3) Directly and uniformly mixing the component A and the component B, pouring the mixture into a cavity of a capacitor, standing at normal temperature for waiting, and still not completing solidification after a plurality of minutes.
Example 4
A preparation method of a temperature reaction type capacitor packaging material comprises the following specific steps:
(1) epoxidized soybean oil is stirred and dewatered for 8 hours in a reaction kettle at 80 ℃ under the reduced pressure condition. Dibenzoyl peroxide and methyl phthalate in a ratio of 1: mixing at a ratio of 6, and stirring and mixing 200 parts of epoxidized soybean oil and 8 parts of dissolved dibenzoyl peroxide to obtain component A.
(2) 100 parts of commercially available unsaturated resin, 1.6 parts of N' N-dimethylbenzylamine and 0.1 part of fumed silica and calcium carbonate are sequentially and uniformly mixed to prepare the component B.
(3) Directly and uniformly mixing the component A and the component B, pouring the mixture into a cavity of a capacitor, standing at normal temperature for 33min, and curing and molding.
Example 5
A preparation method of a temperature reaction type capacitor packaging material comprises the following specific steps:
(1) epoxidized soybean oil is stirred and dewatered for 8 hours in a reaction kettle at 80 ℃ under the reduced pressure condition. Dibenzoyl peroxide and methyl phthalate in a ratio of 1: mixing at a ratio of 6, and stirring and mixing 200 parts of epoxidized soybean oil and 8 parts of dissolved dibenzoyl peroxide to obtain component A.
(2) 100 parts of commercially available unsaturated resin, 2 parts of butyl acrylate, 1.6 parts of N' N-dimethylbenzylamine and 0.1 part of fumed silica and calcium carbonate are sequentially and uniformly mixed to prepare the component B.
(3) Directly and uniformly mixing the component A and the component B, pouring the mixture into a cavity of a capacitor, standing at normal temperature for 28min, and curing and molding.
Example 6
A preparation method of a temperature reaction type capacitor packaging material comprises the following specific steps:
(1) epoxidized soybean oil is stirred and dewatered for 8 hours in a reaction kettle at 80 ℃ under the reduced pressure condition. Dibenzoyl peroxide and methyl phthalate in a ratio of 1: mixing at a ratio of 6, and stirring and mixing 200 parts of epoxidized soybean oil and 8 parts of dissolved dibenzoyl peroxide to obtain component A.
(2) 100 parts of commercially available unsaturated resin, 20 parts of butyl acrylate, 1.6 parts of N' N-dimethylbenzylamine and 0.1 part of fumed silica and calcium carbonate are sequentially and uniformly mixed to prepare the component B.
(3) Directly and uniformly mixing the component A and the component B, filling the mixture into a capacitor, standing at normal temperature for 22min, and curing and molding.
Example 7
A preparation method of a temperature reaction type capacitor packaging material comprises the following specific steps:
(1) epoxidized soybean oil is stirred and dewatered for 8 hours in a reaction kettle at 80 ℃ under the reduced pressure condition. Dibenzoyl peroxide and acetone in a ratio of 1: mixing at a ratio of 30, and stirring and mixing 200 parts of epoxidized soybean oil and 8 parts of dissolved dibenzoyl peroxide to obtain component A.
(2) 100 parts of commercially available unsaturated resin, 20 parts of butyl acrylate, 1.6 parts of N' N-dimethylbenzylamine and 0.1 part of fumed silica and calcium carbonate are sequentially and uniformly mixed to prepare the component B.
(3) Directly and uniformly mixing the component A and the component B, pouring the mixture into a cavity of a capacitor, standing at normal temperature for 23min, and curing and molding.
Example 8
A preparation method of a temperature reaction type capacitor packaging material comprises the following specific steps:
(1) epoxidized soybean oil is stirred and dewatered for 8 hours in a reaction kettle at 80 ℃ under the reduced pressure condition. Dibenzoyl peroxide and methyl phthalate in a ratio of 1: mixing at a ratio of 6, and stirring and mixing 200 parts of epoxidized soybean oil and 8 parts of dissolved dibenzoyl peroxide to obtain component A.
(2) 100 parts of commercially available unsaturated resin, 20 parts of butyl acrylate and 1.6 parts of N' N-dimethylbenzylamine are sequentially and uniformly mixed to prepare the component B.
(3) Directly and uniformly mixing the component A and the component B, filling the mixture into a capacitor, standing at normal temperature for 25min, and curing and molding.
TABLE 1 results of testing the Electrical Properties of the cured oils of the different examples
As reported in table 1, the capacitor should not permanently break down, open or flashover after 536 hours in an oven at a temperature of 85 c at 1.35 times the rated voltage frequency. The determination standard is that delta C/C is less than or equal to 3 percent before and after the test, and delta tg delta is less than or equal to 0.002 after the test. The experiments of the embodiments 1 to 5 of the invention all fail in 536h, the capacity change rate of the unsaturated resin material in the embodiments 6 to 8 still meets the requirement after 536h, and the voltage between shells is qualified, which shows that the epoxidized soybean oil and the commercially available unsaturated resin system have formed a compact network structure, are completely cured, have no mobile phase, and ensure good heat resistance. Therefore, the unsaturated resin packaging material has excellent performance.
TABLE 2 curing results of temperature-responsive capacitor packaging materials
As can be seen from table 2, the present invention provides a temperature-responsive capacitor sealing material using epoxidized soybean oil and an unsaturated resin, which is in an oily gel state at a temperature of 100 ℃ or lower and in a liquid-flowing state at a temperature of 100 ℃ or higher. In the safe temperature below 100 ℃, the gel-like epoxidized soybean oil can improve the brittleness of common unsaturated resin and ensure excellent insulating property. On the other hand, at a higher temperature of more than 100 ℃, the cured epoxy soybean oil recovers the liquid fluidity and can improve the heat dissipation efficiency of the capacitor.
From examples 1, 2 and 3 it can be seen that the higher the ratio of epoxidized soybean oil to unsaturated resin in the formulation, the lower the hardness of the cured epoxidized soybean oil gel and the slower the cure rate, eventually transitioning to a liquid mobile phase that is not curable. In comparative example 6, the capacitor of three groups of examples 1, 2 and 3 can not meet the use requirements. When the proportion of the epoxidized soybean oil in the gel is too low, the oily gel is always kept in a solid state, and the oily gel cannot recover the flow even being heated to more than 100 ℃. The service life under the high-temperature condition is short due to low heat dissipation efficiency; when the proportion of the epoxidized soybean oil in the gel is too high, the corresponding mixture is kept in a liquid state all the time and cannot be solidified, and the problem of grease leakage is easy to occur in the corresponding capacitor product.
The liquid phase separation phenomenon occurred in the encapsulating materials obtained in examples 4 and 5, and all performance indexes were lower than those of the encapsulating material obtained in example 6. If the butyl acrylate in the mixture is insufficient, the oily gel has insufficient capability of solidifying the epoxidized soybean oil, and part of the epoxidized soybean oil is free and is in a liquid phase separation state.
Comparing examples 6 and 7, different diluents have little effect on the curing results.
Comparing examples 6 and 8, the addition of a certain proportion of fillers (fumed silica and calcium carbonate) can improve the strength of the oleogel, inhibit the propagation of cracks and have little influence on the electrical properties of the capacitor.
The above description is only an example of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by using the contents of the present specification and embodiments, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.
Claims (5)
1. A temperature-responsive capacitor packaging material, comprising: at least comprises the following components in parts by weight: an agent A: 15-200 parts of epoxidized soybean oil, 1-10 parts of dibenzoyl peroxide and a solvent thereof; and (2) agent B: 100 parts of commercially available unsaturated resin, 4-30 parts of butyl acrylate, 0.2-2 parts of catalyst and 0.02-0.2 part of filler, wherein a lipophilic cross-linking network is formed through the curing reaction of the unsaturated resin, and epoxy soybean oil molecules are dispersed in the network to form oily gel, so that the curing of the epoxy soybean oil is realized.
2. The temperature-responsive capacitor encapsulant of claim 1, wherein: the solvent comprises one or more of ketone solvent, ester solvent and benzene solvent.
3. The temperature-responsive capacitor encapsulant of claim 2, wherein: the solvent is acetone or methyl phthalate, wherein the minimum ratio of the acetone or methyl phthalate to the dibenzoyl peroxide is 30: 1 and 6: 1.
4. the temperature-responsive capacitor encapsulant of claim 1, wherein: the catalyst comprises one or more of N 'N-dimethylbenzylamine, N' N-dimethylaniline and triethanolamine.
5. A method for preparing the temperature-responsive capacitor encapsulating material as claimed in any one of claims 1 to 4, comprising the steps of:
(1) stirring epoxidized soybean oil in a reaction kettle at 80 ℃ under reduced pressure to remove water; uniformly mixing dibenzoyl peroxide and acetone/methyl phthalate in a certain proportion, and mixing the mixture with epoxy soybean oil in a certain proportion to prepare a component A;
(2) mixing commercially available unsaturated resin, butyl acrylate, a catalyst and a filler in proportion to prepare a component B;
(3) and uniformly mixing the component A and the component B in a proper proportion, filling the mixture into a cavity of a capacitor, standing the mixture at room temperature for finishing the polymerization reaction, and finishing the curing, molding and processing of the grease.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5374600A (en) * | 1990-01-29 | 1994-12-20 | Nippon Shokubai Kagaku Kogyo Co., Ltd. | Oil-absorbent polymer and use therefor |
| CN103540143A (en) * | 2012-07-04 | 2014-01-29 | 江苏泰尔新材料股份有限公司 | Wax for self-healing metalized capacitor |
| JP2014219640A (en) * | 2013-05-10 | 2014-11-20 | 日立化成株式会社 | Edge material for image display device, manufacturing method of image display device, and image display device |
| CN109880566A (en) * | 2019-03-23 | 2019-06-14 | 高路生 | One kind having high thermal stability electronics new material and preparation method thereof |
| CN111171218A (en) * | 2020-01-17 | 2020-05-19 | 北京航空航天大学 | Multi-phase gel with multistable mechanical and shape memory properties and preparation method thereof |
-
2020
- 2020-09-24 CN CN202011020719.3A patent/CN112210181B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5374600A (en) * | 1990-01-29 | 1994-12-20 | Nippon Shokubai Kagaku Kogyo Co., Ltd. | Oil-absorbent polymer and use therefor |
| CN103540143A (en) * | 2012-07-04 | 2014-01-29 | 江苏泰尔新材料股份有限公司 | Wax for self-healing metalized capacitor |
| JP2014219640A (en) * | 2013-05-10 | 2014-11-20 | 日立化成株式会社 | Edge material for image display device, manufacturing method of image display device, and image display device |
| CN109880566A (en) * | 2019-03-23 | 2019-06-14 | 高路生 | One kind having high thermal stability electronics new material and preparation method thereof |
| CN111171218A (en) * | 2020-01-17 | 2020-05-19 | 北京航空航天大学 | Multi-phase gel with multistable mechanical and shape memory properties and preparation method thereof |
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| CN112210181B (en) | 2022-12-27 |
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