CN111154234A - Preparation method of medium-high temperature self-repairing insulating material - Google Patents
Preparation method of medium-high temperature self-repairing insulating material Download PDFInfo
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Abstract
The application belongs to the technical field of electrical materials, and particularly relates to a preparation method of a medium-high temperature self-repairing insulating material. Most of the existing extrinsic self-repairing systems are bi-component microcapsule systems, the systems are complex in structure, the repairing agent is difficult to be ensured to be contacted with a catalyst and complete self-repairing before failure when micro-discharge defects occur, and common single-component system repairing liquid contains unsaturated double bonds and is easy to fail in advance at medium and high temperature. Firstly, an imidazole-added epoxy resin matrix with anion catalysis capability is synthesized, and microcapsules coated with stable repair liquid are introduced into the matrix, so that the insulating material is endowed with the capability of repairing micro-discharge defects. When the electric tree caused by micro discharge defects develops into the microcapsule, the microcapsule is broken and the repairing liquid is filled in the electric tree channel, and then under the condition of medium and high temperature, the repairing liquid is solidified under the catalysis of oxygen anion groups in the channel wall, so that the electric tree defects are repaired, and meanwhile, the electric performance is completely recovered.
Description
Technical Field
The application belongs to the technical field of electrical materials, and particularly relates to a preparation method of a medium-high temperature self-repairing insulating material.
Background
Organic matters such as polyethylene, silicon rubber, epoxy resin and the like and composite materials thereof are widely applied to electrical insulation, and in the using process, micro-discharge defects represented by electric trees and water trees are inevitably generated in the organic matters along with long-term aging, and the micro-defects further develop to cause the insulation damage of materials, so that the insulation failure and the equipment failure are caused. Therefore, if the high polymer material can have a self-repairing function, the defects can be repaired at the early stage of defect development, so that the problems can be solved, the service life of the insulating medium is remarkably prolonged, and the safety of the product is improved. Aiming at micro-discharge defects, particularly water tree defects, in the cable, the early repair technology mainly adopts dry N2The three materials of hydrophobic compound and siloxane are used as repairing media to artificially repair the cable with reduced insulation strength so as to prolong the service life of the cable. The method is not widely applied due to the reasons of large manual intervention, large resource consumption, poor effect, unobvious effect on the defects of the electric tree and the like.
In 2001, the concept of self-repairing a resin-based composite material by using microcapsules is firstly proposed, the microcapsules filled with repairing liquid are embedded in the composite material, when micro defects are generated in the material, the defects expand to cause the microcapsules to break and release the repairing liquid to contact with a catalyst embedded in a matrix to generate a cross-linking polymerization reaction to repair the defect surface, and therefore the purpose of preventing and repairing the defects is achieved. In principle, self-healing materials can be divided into two categories: (1) intrinsic self-repairing, namely, after the local material is damaged, the aim of repairing is achieved through thermal diffusion and chemical reaction; (2) the purpose of self-repairing is achieved through transportation and chemical reaction of external materials after the local materials are damaged. The micro-discharge defects are damaged along with the chemical properties of the materials, so that the original self-repairing performance of the local materials is damaged, and the intrinsic self-repairing cannot be applied to the self-repairing of the micro-discharge defects in principle. The purpose of self-repairing is achieved through transportation of external materials by extrinsic self-repairing, the problems are effectively solved, and the method is more suitable for self-repairing of micro-discharge defects.
However, most of the existing extrinsic self-repairing systems are two-component microcapsule systems, the systems are complex in structure, the repairing agent and the catalyst need to be stored and dispersed in the polymer respectively, and when micro-discharge defects occur, it is difficult to ensure that the repairing agent can contact with the catalyst before the repairing agent fails and complete self-repairing. However, the repair liquid used in the existing single-component microcapsule system (such as an ultraviolet light trigger system) contains unsaturated double bonds, and is easy to fail in advance at medium and high temperature, so that the repair liquid cannot be applied to medium and high temperature operation conditions.
Disclosure of Invention
1. Technical problem to be solved
Based on the problem that most of the existing extrinsic self-repairing systems are two-component microcapsule systems, the systems are complex in structure, a repairing agent and a catalyst are required to be stored and dispersed in a polymer respectively, the repairing agent is difficult to be ensured to be in contact with the catalyst before failure and to complete self-repairing when micro-discharge defects occur, and common single-component system repairing liquid contains unsaturated double bonds and is easy to fail in advance at medium and high temperature, the application provides a preparation method of a medium and high temperature self-repairing insulating material.
2. Technical scheme
In order to achieve the above purpose, the present application provides a method for preparing a medium-high temperature self-repairing insulating material, comprising the following steps:
step 1: uniformly mixing epoxy resin and epoxy resin reactive diluent according to a proportion to prepare a repairing liquid;
step 2: preparing an aqueous solution containing sodium dodecyl benzene sulfonate and polyvinyl alcohol, slowly adding the repair liquid into the aqueous solution, and stirring to form uniformly dispersed oil-in-water core material emulsion;
and step 3: preparing urea and formaldehyde into a solution according to a proportion, stirring to form a water-soluble prepolymer solution of mono-methylol urea and dihydroxy-methylol urea, adding a proper amount of deionized water into the prepolymer, cooling to room temperature, and adding diluted hydrochloric acid to adjust the pH value to 7;
and 4, step 4: adding the prepolymer solution into the oil-in-water core material emulsion, adding a catalyst and a pH value regulator, regulating the pH value of the solution to 3-4, heating to 50-60 ℃, reacting for 3-5 hours, removing unreacted core materials and wall materials, cooling, washing, sieving, and naturally drying to obtain microcapsules;
and 5: mixing epoxy resin and 2-ethyl-4-methylimidazole according to a proportion, adding a normal-temperature curing agent of the epoxy resin and the microcapsules, uniformly mixing, degassing in vacuum, and pouring into a mold for curing to obtain the self-repairing epoxy resin insulating material with the electric damage self-repairing capability.
Another embodiment provided by the present application is: the epoxy resin in the step 1 is bisphenol A type epoxy resin or bisphenol F type epoxy resin.
Another embodiment provided by the present application is: the epoxy resin reactive diluent in the step 1 is alkylene glycidol, butyl glycidyl ether, 1, 4-butanediol diglycidyl ether, ethylene glycol diglycidyl ether, phenyl glycidyl ether or polypropylene glycol diglycidyl ether.
Another embodiment provided by the present application is: in the step 1, the ratio of the epoxy resin to the epoxy resin reactive diluent is 2: 1-4: 1.
Another embodiment provided by the present application is: and in the step 2, stirring is mechanically stirred for 20-30 min at the rotating speed of 1000-1500 r/min.
Another embodiment provided by the present application is: the ratio of urea to formaldehyde in step 3 is 1: 2.
Another embodiment provided by the present application is: in the step 4, the catalyst is resorcinol, and the pH value regulator is ammonium chloride.
Another embodiment provided by the present application is: the ratio of the prepolymer to the oil-in-water core emulsion in the step 4 is 1: 2-1: 1.
another embodiment provided by the present application is: the step 5 of curing comprises pre-curing at 30 ℃ for 4 hours and then curing at 60-80 ℃ for 12 hours.
Another embodiment provided by the present application is: the use temperature of the self-repairing epoxy resin insulating material with the electric damage self-repairing capability is 50-100 ℃.
3. Advantageous effects
Compared with the prior art, the preparation method of the medium-high temperature self-repairing insulating material has the beneficial effects that:
the preparation method of the insulating material provided by the application widens the application range of the microcapsule-based self-repairing insulating material aiming at the situation that the existing light-triggered microcapsule-based self-repairing insulating material cannot be applied to a matrix (such as inorganic oxide particle filler or glass fiber) which is difficult to transmit ultraviolet light or medium-high temperature operation.
The preparation method of the medium-high temperature self-repairing insulating material solves the problem that the repairing liquid of the microcapsule-based self-repairing insulating material is easy to lose efficacy at medium-high temperature, and meanwhile, the light transmittance of the base material is not required, so that the composite insulating material can be formed with inorganic oxide filler or glass fiber and the like, and practical application scenes are widened.
According to the preparation method of the medium-high temperature self-repairing insulating material, the imidazole-added epoxy resin matrix with anion catalysis capability is synthesized, and the microcapsule coated with the stable repairing liquid is introduced into the matrix, so that the insulating material is endowed with the capability of repairing micro discharge defects. When the electric tree caused by micro discharge defects develops into the microcapsule, the microcapsule is broken and the repairing liquid is filled in the electric tree channel, and then under the condition of medium and high temperature, the repairing liquid is solidified under the catalysis of oxygen anion groups in the channel wall, so that the electric tree defects are repaired, and meanwhile, the electric performance is completely recovered.
According to the preparation method of the medium-high temperature self-repairing insulating material, the designed self-repairing mechanism does not need any additional human intervention, and the complete self-repairing after the damage is generated can be realized.
The preparation method of the medium-high temperature self-repairing insulating material is suitable for being used as an insulating material of insulating equipment under medium-high temperature operation conditions, can be mixed with glass fibers and nano/micron fillers to obtain a composite insulating material with wider application, and can effectively prolong the service life and improve the reliability of the insulating material.
According to the preparation method of the medium-high temperature self-repairing insulating material, a catalyst required in a common external-aid self-repairing system is not adopted, 2-ethyl-4-methylimidazole is used for modifying common epoxy, so that oxyanions capable of catalyzing anion polymerization reaction are grafted in a molecular chain of the epoxy, and the capability of curing repairing liquid can be given to the epoxy on the premise of not influencing the insulating property of a substrate. Because the 2-ethyl-4-methylimidazole is a micromolecular liquid organic matter, the problem of uneven mixing is solved when the 2-ethyl-4-methylimidazole is mixed with a matrix, and the problem of insufficient contact with a repair liquid is also solved.
According to the preparation method of the medium-high temperature self-repairing insulating material, a two-step curing method is used for maintaining the catalytic activity of oxygen anions. The epoxy group on the epoxy resin in the matrix is firstly subjected to one-step addition reaction with 2-ethyl-4-methylimidazole to generate oxyanion by curing for 4 hours at normal temperature (30-40 ℃), and the etherification reaction initiated by the oxyanion requires a high temperature and is slow at normal temperature, so that the oxyanion can be protected from being damaged in the synthesis process of the matrix.
According to the preparation method of the medium-high temperature self-repairing insulating material, the normal temperature curing agent of the epoxy resin is used for being matched with the etherification polymerization reaction of the oxyanion, so that the curing agent for curing the epoxy resin matrix in the preparation of the self-repairing insulating material is mainly the normal temperature curing agent, and the oxyanion reserved in the matrix is mainly used when the epoxy resin repairing liquid is cured in the follow-up micro-discharge defect repairing process.
According to the preparation method of the medium-high temperature self-repairing insulating material, the content of the added 2-ethyl-4-methylimidazole in the matrix is 3-5 wt.%. The imidazole added in the range does not reduce the insulating property of the matrix material, but can enhance the performance of the material to a certain extent, and can endow the material with reliable self-repairing capability. Too low an amount (less than 3 wt.%) will affect the self-healing ability of the material, while too much an amount (greater than 5 wt.%) will affect the insulating properties of the material.
According to the preparation method of the medium-high temperature self-repairing insulating material, the prepared stable repairing liquid is bisphenol A type epoxy resin or bisphenol F type epoxy resin, and the epoxy resin does not contain unsaturated double bonds, so that the medium-high temperature self-repairing insulating material has high stability; and the used diluent is an active diluent, and in order to ensure that the prepared stable repairing liquid has proper viscosity and good insulating property after curing, the mixing proportion is that the mass ratio of the epoxy resin in the final mixture is 65-80%.
According to the preparation method of the medium-high temperature self-repairing insulating material, the content of the added self-repairing microcapsules is 3-10 wt% of the matrix epoxy resin. Too many microcapsules will affect the properties of the material itself, while too few microcapsules will affect the self-healing effect.
According to the preparation method of the medium-high temperature self-repairing insulating material, the environmental heat of the insulating material during operation is used as a repairing condition, and the triggering of self-repairing starts when the repairing liquid contacts a micro-discharge defect channel. Before the repair liquid flows into the defect channel, the capsule wall of the microcapsule can be isolated to prevent the repair liquid from failing due to contact with oxygen anions.
Drawings
FIG. 1 is a reaction scheme of 2-ethyl-4-methylimidazole of the present application reacting with an epoxy resin to produce an active oxygen anion;
FIG. 2 is a reaction scheme of the two-step curing process of the present application to obtain an oxyanion-containing epoxy resin matrix;
fig. 3 is a schematic structural view and a schematic mechanism of self-repairing function of the self-repairing insulating material of the present application.
Detailed Description
Hereinafter, specific embodiments of the present application will be described in detail with reference to the accompanying drawings, and it will be apparent to those skilled in the art from this detailed description that the present application can be practiced. Features from different embodiments may be combined to yield new embodiments, or certain features may be substituted for certain embodiments to yield yet further preferred embodiments, without departing from the principles of the present application.
DGEBA is bisphenol A epoxy resin, 24-EMI is 2-ethyl-4-methylimidazole, O-/OH adduct is oxyanion or hydroxyl adduct, PAA is phenolic aldehyde amine, EMI-modified epoxy resin is imidazole modified epoxy resin, and EMI-adduct is imidazole adduct, namely O-the/OH adduct, Self-healing composite is a Self-repairing composite.
Referring to fig. 1 to 3, the application provides a preparation method of a medium-high temperature self-repairing insulating material, which comprises the following steps:
step 1: uniformly mixing epoxy resin and epoxy resin reactive diluent according to a proportion to prepare a repairing liquid;
step 2: preparing an aqueous solution containing sodium dodecyl benzene sulfonate and polyvinyl alcohol, slowly adding the repair liquid into the aqueous solution, and stirring to form uniformly dispersed oil-in-water core material emulsion;
and step 3: preparing urea and formaldehyde into a solution according to a proportion, stirring to form a water-soluble prepolymer solution of mono-methylol urea and dihydroxy-methylol urea, adding a proper amount of deionized water into the prepolymer, cooling to room temperature, and adding diluted hydrochloric acid to adjust the pH value to 7;
and 4, step 4: adding the prepolymer solution into the oil-in-water core material emulsion, adding a catalyst and a pH value regulator, regulating the pH value of the solution to 3-4, heating to 50-60 ℃, reacting for 3-5 hours, removing unreacted core materials and wall materials, cooling, washing, sieving, and naturally drying to obtain microcapsules;
and 5: mixing epoxy resin and 2-ethyl-4-methylimidazole according to a proportion, adding a normal-temperature curing agent of the epoxy resin and the microcapsules, uniformly mixing, degassing in vacuum, and pouring into a mold for curing to obtain the self-repairing epoxy resin insulating material with the electric damage self-repairing capability.
Furthermore, in the step 1, the epoxy resin is bisphenol A type epoxy resin (EPON828) or bisphenol F type epoxy resin (EPON862), and the epoxy resin does not contain unsaturated double bonds, so that the stability is good.
Further, in the step 1, the epoxy resin reactive diluent is alkylene glycidyl (HK-66), butyl glycidyl ether (501), 1, 4-butanediol diglycidyl ether (622), ethylene glycol diglycidyl ether) (669), phenyl glycidyl ether (690), and polypropylene glycol diglycidyl ether (X-632).
Further, the ratio of the epoxy resin to the epoxy resin reactive diluent in the step 1 is 2: 1-4: 1.
Further, in the step 2, stirring is mechanically stirred for 20min to 30min at the rotating speed of 1000 to 1500 r/min.
Further, the ratio of urea to formaldehyde in the step 3 is 1: 2.
Further, in the step 4, the catalyst is resorcinol, and the pH value regulator is ammonium chloride.
Further, the ratio of the prepolymer to the oil-in-water core emulsion in the step 4 is 1: 2-1: 1.
further, the curing in the step 5 comprises pre-curing at 30 ℃ for 4 hours, and then curing at 60 ℃ to 80 ℃ for 12 hours.
Further, the use temperature of the self-repairing epoxy resin insulating material with the electric damage self-repairing capability is 50-100 ℃.
Examples
Uniformly mixing bisphenol A type epoxy resin (EPON828) or bisphenol F type epoxy resin (EPON862), bisphenol A type epoxy resin (EPON828) or bisphenol F type epoxy resin (EPON862) according to a certain proportion to obtain a repair liquid for later use. The mixing proportion is that the mass ratio of the epoxy resin in the final mixture is 65-80% so as to ensure that the repair liquid has proper viscosity and sufficient insulation performance after curing.
Preparing an aqueous solution containing 1 wt.% of sodium dodecyl benzene sulfonate and 0.2 wt.% of polyvinyl alcohol, slowly adding 10 wt.% to 20 wt.% of the prepared stable repair liquid, and mechanically stirring at a rotating speed of 1000-1500 r/min for 20min to 30min to completely emulsify the repair liquid to form the uniformly dispersed oil-in-water core emulsion.
And then preparing urea and formaldehyde into a solution according to a molar ratio of 1:2, magnetically stirring the solution at 70 ℃ under an alkaline condition with the pH value of 8-9 for reacting for 1 hour to form a water-soluble prepolymer of the mono-and dihydroxymethylureas, adding a proper amount of deionized water into the prepolymer, cooling to room temperature, and adding diluted hydrochloric acid to adjust the pH value to 7. Adding the obtained prepolymer solution into the oil-in-water core material emulsion, adding a catalyst of resorcinol and a pH value regulator of ammonium chloride, regulating the pH value of the solution to 3-4 by using 1-2% by mass of dilute hydrochloric acid, heating to 50-60 ℃ at the speed of 1 ℃/min, reacting for 3-5 hours, removing unreacted core materials and wall materials, cooling, washing, sieving, and naturally drying to obtain microcapsules; the addition amount of the catalyst is 3-6 wt% of the prepolymer, and the addition amount of the pH value regulator is 5-6 wt% of the prepolymer;
mixing epoxy resin and 2-ethyl-4-methylimidazole in a certain proportion, adding a normal-temperature curing agent with a proper content of epoxy resin and self-repairing microcapsules, uniformly mixing, removing gas in vacuum, and pouring into a mold. The self-repairing epoxy resin insulating material with the electric damage self-repairing capability is obtained by pre-curing for 4 hours at 30 ℃ and then curing for 12 hours at 60-80 ℃. The epoxy resin is epoxy resin with good electrical insulation performance, such as E51, EPON828 or E44. The curing agent is amine curing agent capable of curing epoxy resin at normal temperature, and includes aliphatic amine, alicyclic amine, phenolic amine, polyamide, etc. The mass percentage of the microcapsule in the epoxy resin matrix is 3-10%, and the addition amount of the curing agent and the stoichiometric ratio of the matrix epoxy resin are equivalent; the adding amount of the 2-ethyl-4-methylimidazole is 3-5 wt% of the matrix.
The suitable operating conditions of the obtained electrical damage self-repairing insulating material are 50-100 ℃, and too low affects the repairing efficiency, while too high affects the service life of the material.
By constructing a matrix containing oxygen anions capable of catalyzing anion polymerization reaction and matching with the self-repairing microcapsule, the material can spontaneously repair the micro-discharge defect under the medium-high temperature condition.
According to the method, 2-ethyl-4-methylimidazole is utilized to construct the epoxy resin matrix grafted with oxyanions, and self-repairing microcapsules containing stable repairing liquid are introduced to endow the material with the capability of repairing micro-discharge defects, so that the method has the advantages of no influence on the insulating property of the matrix, no problem of uniformity of mixing, long-term stability, high-medium temperature stability and the like. Meanwhile, the self-repairing material is realized only by depending on the contact of the repairing liquid and the matrix, but not depending on external triggering, and can be mixed with glass fiber, nano micron filler and the like to obtain the composite insulating material, so that the application range of the self-repairing material is widened.
Experiments prove that the method is feasible, the micro-discharge defect is completely repaired on the premise of not influencing the insulation performance of the matrix, and the performance of the insulation material after repair is not reduced but enhanced.
Alternatives to the present application include the use of epoxy resins, the matrix resins used in the present application being epoxy resins with good electrical insulation properties such as E51, EPON828 or E44, etc.
The alternative scheme of this application includes the substitution of used curing agent, and the curing agent that this application used is the amine curing agent that can normal atmospheric temperature cured epoxy, includes aliphatic amine, alicyclic amine, phenol aldehyde amine, polyamide, modified aliphatic amine etc..
A potential alternative to the 2-ethyl-4-methylimidazole used in the present application is the substitution of possible alternatives including imidazole, 2-methylimidazole, and the like.
A potential alternative to the present application is the substitution of the diluent used, possible alternatives including alkylene glycidyl (HK-66), butyl glycidyl ether (501), 1, 4-butanediol diglycidyl ether (622), ethylene glycol diglycidyl ether (669), phenyl glycidyl ether (690), polypropylene glycol diglycidyl ether (X-632), etc.;
a potential alternative of the present application may be to perform nano-modification of the used stable repair liquid, such as adding nano boron nitride, silicon dioxide, etc., to improve the insulation performance after curing.
Although the present application has been described above with reference to specific embodiments, those skilled in the art will recognize that many changes may be made in the configuration and details of the present application within the principles and scope of the present application. The scope of protection of the application is determined by the appended claims, and all changes that come within the meaning and range of equivalency of the technical features are intended to be embraced therein.
Claims (10)
1. A preparation method of a medium-high temperature self-repairing insulating material is characterized by comprising the following steps: the method comprises the following steps:
step 1: uniformly mixing epoxy resin and epoxy resin reactive diluent according to a proportion to prepare a repairing liquid;
step 2: preparing an aqueous solution containing sodium dodecyl benzene sulfonate and polyvinyl alcohol, slowly adding the repair liquid into the aqueous solution, and stirring to form uniformly dispersed oil-in-water core material emulsion;
and step 3: preparing urea and formaldehyde into a solution according to a proportion, stirring to form a water-soluble prepolymer solution of mono-methylol urea and dihydroxy-methylol urea, adding a proper amount of deionized water into the prepolymer solution, cooling to room temperature, and adding diluted hydrochloric acid to adjust the pH value to 7;
and 4, step 4: adding the prepolymer solution into the oil-in-water core material emulsion, adding a catalyst and a pH value regulator, regulating the pH value of the solution to 3-4, heating to 50-60 ℃, reacting for 3-5 hours, removing unreacted core materials and wall materials, cooling, washing, sieving, and naturally drying to obtain microcapsules;
and 5: mixing epoxy resin and 2-ethyl-4-methylimidazole according to a proportion, adding a normal-temperature curing agent of the epoxy resin and the microcapsules, uniformly mixing, degassing in vacuum, and pouring into a mold for curing to obtain the self-repairing epoxy resin insulating material with the electric damage self-repairing capability.
2. The preparation method of the medium-high temperature self-repairing insulating material as claimed in claim 1, characterized in that: the epoxy resin in the step 1 is bisphenol A type epoxy resin or bisphenol F type epoxy resin.
3. The preparation method of the medium-high temperature self-repairing insulating material as claimed in claim 1, characterized in that: the epoxy resin reactive diluent in the step 1 is alkylene glycidol, butyl glycidyl ether, 1, 4-butanediol diglycidyl ether, ethylene glycol diglycidyl ether, phenyl glycidyl ether or polypropylene glycol diglycidyl ether.
4. The preparation method of the medium-high temperature self-repairing insulating material as claimed in claim 1, characterized in that: in the step 1, the ratio of the epoxy resin to the epoxy resin reactive diluent is 2: 1-4: 1.
5. The preparation method of the medium-high temperature self-repairing insulating material as claimed in claim 1, characterized in that: and in the step 2, stirring is mechanically stirred for 20-30 min at the rotating speed of 1000-1500 r/min.
6. The preparation method of the medium-high temperature self-repairing insulating material as claimed in claim 1, characterized in that: the ratio of urea to formaldehyde in step 3 is 1: 2.
7. The preparation method of the medium-high temperature self-repairing insulating material as claimed in claim 1, characterized in that: in the step 4, the catalyst is resorcinol, and the pH value regulator is ammonium chloride.
8. The preparation method of the medium-high temperature self-repairing insulating material as claimed in claim 1, characterized in that: the ratio of the prepolymer to the oil-in-water core emulsion in the step 4 is 1: 2-1: 1.
9. the preparation method of the medium-high temperature self-repairing insulating material as claimed in claim 1, characterized in that: the step 5 of curing comprises pre-curing at 30 ℃ for 4 hours and then curing at 60-80 ℃ for 12 hours.
10. The preparation method of the medium-high temperature self-repairing insulating material as claimed in any one of claims 1 to 9, characterized by comprising the following steps: the use temperature of the self-repairing epoxy resin insulating material with the electric damage self-repairing capability is 50-100 ℃.
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| CN112210122A (en) * | 2020-10-13 | 2021-01-12 | 清华大学 | Preparation method and application of self-repairing microcapsule |
| CN114874587A (en) * | 2022-06-17 | 2022-08-09 | 重庆大学 | Epoxy resin composite insulating material with mechanical damage targeting self-healing performance |
| CN115160739A (en) * | 2022-08-10 | 2022-10-11 | 重庆大学 | Electrical damage self-repairing epoxy resin composite insulating material and preparation method thereof |
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| CN104356596A (en) * | 2014-10-20 | 2015-02-18 | 清华大学 | Preparation method of electrical insulating layer material with micro-discharge defect self-repairing function |
| US20170158883A1 (en) * | 2015-12-04 | 2017-06-08 | The Board Of Trustees Of The University Of Illinois | Autonomic damage indication in coatings |
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| CN101215408A (en) * | 2008-01-18 | 2008-07-09 | 中山大学 | High temperature self-restoring epoxy resin material and preparation method thereof |
| CN104356596A (en) * | 2014-10-20 | 2015-02-18 | 清华大学 | Preparation method of electrical insulating layer material with micro-discharge defect self-repairing function |
| US20170158883A1 (en) * | 2015-12-04 | 2017-06-08 | The Board Of Trustees Of The University Of Illinois | Autonomic damage indication in coatings |
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| CN112210122A (en) * | 2020-10-13 | 2021-01-12 | 清华大学 | Preparation method and application of self-repairing microcapsule |
| CN112210122B (en) * | 2020-10-13 | 2021-08-27 | 清华大学 | Preparation method of self-repairing insulating material |
| CN114874587A (en) * | 2022-06-17 | 2022-08-09 | 重庆大学 | Epoxy resin composite insulating material with mechanical damage targeting self-healing performance |
| CN115160739A (en) * | 2022-08-10 | 2022-10-11 | 重庆大学 | Electrical damage self-repairing epoxy resin composite insulating material and preparation method thereof |
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