CN117487128A - Polythiourea-based block copolymer coating for improving epoxy resin surface flashover voltage and preparation method thereof - Google Patents
Polythiourea-based block copolymer coating for improving epoxy resin surface flashover voltage and preparation method thereof Download PDFInfo
- Publication number
- CN117487128A CN117487128A CN202311579687.4A CN202311579687A CN117487128A CN 117487128 A CN117487128 A CN 117487128A CN 202311579687 A CN202311579687 A CN 202311579687A CN 117487128 A CN117487128 A CN 117487128A
- Authority
- CN
- China
- Prior art keywords
- polythiourea
- block copolymer
- based block
- epoxy resin
- solution
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 229920001400 block copolymer Polymers 0.000 title claims abstract description 82
- 239000003822 epoxy resin Substances 0.000 title claims abstract description 58
- 229920000647 polyepoxide Polymers 0.000 title claims abstract description 58
- 238000000576 coating method Methods 0.000 title claims abstract description 44
- 239000011248 coating agent Substances 0.000 title claims abstract description 43
- 238000002360 preparation method Methods 0.000 title claims abstract description 13
- 239000002798 polar solvent Substances 0.000 claims abstract description 38
- RTZKZFJDLAIYFH-UHFFFAOYSA-N Diethyl ether Chemical compound CCOCC RTZKZFJDLAIYFH-UHFFFAOYSA-N 0.000 claims abstract description 30
- 239000012528 membrane Substances 0.000 claims abstract description 22
- 239000007787 solid Substances 0.000 claims abstract description 16
- 150000004985 diamines Chemical class 0.000 claims abstract description 13
- 238000003756 stirring Methods 0.000 claims abstract description 12
- UHOVQNZJYSORNB-UHFFFAOYSA-N benzene Substances C1=CC=CC=C1 UHOVQNZJYSORNB-UHFFFAOYSA-N 0.000 claims abstract description 11
- 239000002904 solvent Substances 0.000 claims abstract description 10
- 238000001914 filtration Methods 0.000 claims abstract description 9
- 238000002791 soaking Methods 0.000 claims abstract description 8
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 26
- 238000010438 heat treatment Methods 0.000 claims description 26
- ZMXDDKWLCZADIW-UHFFFAOYSA-N N,N-Dimethylformamide Chemical group CN(C)C=O ZMXDDKWLCZADIW-UHFFFAOYSA-N 0.000 claims description 24
- 238000000034 method Methods 0.000 claims description 24
- WYURNTSHIVDZCO-UHFFFAOYSA-N Tetrahydrofuran Chemical group C1CCOC1 WYURNTSHIVDZCO-UHFFFAOYSA-N 0.000 claims description 14
- 229910052757 nitrogen Inorganic materials 0.000 claims description 13
- CKOFBUUFHALZGK-UHFFFAOYSA-N 3-[(3-aminophenyl)methyl]aniline Chemical group NC1=CC=CC(CC=2C=C(N)C=CC=2)=C1 CKOFBUUFHALZGK-UHFFFAOYSA-N 0.000 claims description 7
- FXHOOIRPVKKKFG-UHFFFAOYSA-N N,N-Dimethylacetamide Chemical compound CN(C)C(C)=O FXHOOIRPVKKKFG-UHFFFAOYSA-N 0.000 claims description 6
- 239000011148 porous material Substances 0.000 claims description 6
- 230000035484 reaction time Effects 0.000 claims description 6
- 230000007480 spreading Effects 0.000 claims description 6
- 150000001412 amines Chemical class 0.000 claims description 5
- YLQBMQCUIZJEEH-UHFFFAOYSA-N tetrahydrofuran Natural products C=1C=COC=1 YLQBMQCUIZJEEH-UHFFFAOYSA-N 0.000 claims description 4
- 239000004205 dimethyl polysiloxane Substances 0.000 claims description 3
- 229920000435 poly(dimethylsiloxane) Polymers 0.000 claims description 3
- -1 polydimethylsiloxane Polymers 0.000 claims description 3
- 239000011810 insulating material Substances 0.000 abstract description 4
- 239000000126 substance Substances 0.000 abstract 1
- 239000004593 Epoxy Substances 0.000 description 14
- 239000000463 material Substances 0.000 description 8
- 230000008569 process Effects 0.000 description 7
- 238000010586 diagram Methods 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 238000010345 tape casting Methods 0.000 description 4
- 238000009489 vacuum treatment Methods 0.000 description 4
- ZZTCPWRAHWXWCH-UHFFFAOYSA-N diphenylmethanediamine Chemical compound C=1C=CC=CC=1C(N)(N)C1=CC=CC=C1 ZZTCPWRAHWXWCH-UHFFFAOYSA-N 0.000 description 3
- 238000009413 insulation Methods 0.000 description 3
- 239000012212 insulator Substances 0.000 description 3
- 239000000178 monomer Substances 0.000 description 3
- 239000012299 nitrogen atmosphere Substances 0.000 description 3
- 229920001577 copolymer Polymers 0.000 description 2
- 238000003682 fluorination reaction Methods 0.000 description 2
- LNEPOXFFQSENCJ-UHFFFAOYSA-N haloperidol Chemical compound C1CC(O)(C=2C=CC(Cl)=CC=2)CCN1CCCC(=O)C1=CC=C(F)C=C1 LNEPOXFFQSENCJ-UHFFFAOYSA-N 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 239000012298 atmosphere Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 238000010292 electrical insulation Methods 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 150000002148 esters Chemical class 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000000383 hazardous chemical Substances 0.000 description 1
- 231100000206 health hazard Toxicity 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000000752 ionisation method Methods 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 239000002105 nanoparticle Substances 0.000 description 1
- 238000004062 sedimentation Methods 0.000 description 1
- 238000003949 trap density measurement Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/70—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the isocyanates or isothiocyanates used
- C08G18/72—Polyisocyanates or polyisothiocyanates
- C08G18/74—Polyisocyanates or polyisothiocyanates cyclic
- C08G18/76—Polyisocyanates or polyisothiocyanates cyclic aromatic
- C08G18/7614—Polyisocyanates or polyisothiocyanates cyclic aromatic containing only one aromatic ring
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/08—Processes
- C08G18/10—Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G18/00—Polymeric products of isocyanates or isothiocyanates
- C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
- C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
- C08G18/30—Low-molecular-weight compounds
- C08G18/32—Polyhydroxy compounds; Polyamines; Hydroxyamines
- C08G18/3225—Polyamines
- C08G18/3237—Polyamines aromatic
- C08G18/3243—Polyamines aromatic containing two or more aromatic rings
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J7/00—Chemical treatment or coating of shaped articles made of macromolecular substances
- C08J7/04—Coating
- C08J7/0427—Coating with only one layer of a composition containing a polymer binder
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D175/00—Coating compositions based on polyureas or polyurethanes; Coating compositions based on derivatives of such polymers
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D5/00—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2363/00—Characterised by the use of epoxy resins; Derivatives of epoxy resins
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2475/00—Characterised by the use of polyureas or polyurethanes; Derivatives of such polymers
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Wood Science & Technology (AREA)
- Manufacture Of Macromolecular Shaped Articles (AREA)
Abstract
The invention provides a polythiourea-based block copolymer coating for improving the surface flashover voltage of epoxy resin and a preparation method thereof, wherein a polythiourea solution is prepared by 1, 4-benzene diisoisothiocyanate, a weak polar solvent, organic diamine and amine-terminated oligomer; collecting the polythiourea solution into a semipermeable membrane, stirring and soaking the semipermeable membrane in diethyl ether, and removing unreacted substances to obtain a polythiourea-based block copolymer product; removing the solvent from the polythiourea-based block copolymer product to obtain a solid polythiourea-based block copolymer; placing the solid polythiourea-based block copolymer in a polar solution, stirring until the solid polythiourea-based block copolymer is completely dissolved, and filtering to obtain a clear polythiourea-based block copolymer solution; and paving the polythiourea-based block copolymer solution on the epoxy resin heated at constant temperature to obtain an epoxy resin sample of the polythiourea-based block copolymer coating. The invention can change the surface flashover voltage of the epoxy resin, has low difficulty in the coating preparation process and strong reliability, and can be widely applied to the field of high-voltage insulating materials.
Description
Technical Field
The invention belongs to the field of high-voltage insulating materials, and particularly relates to a polythiourea-based block copolymer coating for improving the surface flashover voltage of epoxy resin and a preparation method thereof.
Background
Epoxy resin has good electrical and mechanical properties, and is widely applied to insulating parts of electric equipment, such as basin-type insulators of gas-insulated switchgear. For basin-type insulators, the surface flashover of the gas-solid interface is a main cause of insulation failure of the basin-type insulators, so that the safe operation of the electric equipment is affected, and serious economic loss is possibly caused. Therefore, the improvement of the surface flashover voltage of the epoxy resin in the atmosphere has important significance for ensuring the safe and reliable operation of the electric equipment.
Increasing the flashover voltage along the surface has been a hot study in the field of electrical insulation, common methods such as nano doping, surface fluorination, etc. The nano doping pure preparation process needs to overcome the problem of sedimentation of nano particles in a matrix, and is complex to operate; surface fluorination presents health hazards to operators and more serious environmental pollution problems.
Disclosure of Invention
The invention aims to provide a polythiourea-based block copolymer coating for improving the surface flashover voltage of epoxy resin and a preparation method thereof, so as to solve the problems in the prior art.
In order to achieve the above purpose, the invention adopts the following technical scheme:
a preparation method of a polythiourea-based block copolymer coating for improving the surface flashover voltage of epoxy resin comprises the following steps:
1) Completely dissolving 1, 4-benzene diisoisothiocyanate in a weak polar solvent, then adding organic diamine, and reacting under the condition of nitrogen and room temperature to obtain a polythiourea solution A;
2) Completely dissolving amine-terminated oligomer in a weak polar solvent, adding the weak polar solvent into the polythiourea solution A, and reacting under the condition of nitrogen and heating to obtain a polythiourea solution B;
3) Collecting the obtained polythiourea solution B into a semipermeable membrane, stirring and soaking the semipermeable membrane in diethyl ether, and removing unreacted 1, 4-benzene diisothiocyanate, organic diamine and amine-terminated oligomer to obtain a polythiourea-based block copolymer product;
4) Removing the solvent from the polythiourea-based block copolymer product under vacuum conditions to obtain a solid polythiourea-based block copolymer;
5) Placing the solid polythiourea-based block copolymer in a polar solution, and stirring until the solid polythiourea-based block copolymer is completely dissolved;
6) Filtering the solution obtained in the step 5) to obtain a clear polythioureido block copolymer solution;
7) Spreading the polythiourea-based block copolymer solution on the epoxy resin heated at constant temperature, and removing the polar solvent by adopting gradient heating to obtain an epoxy resin sample containing the polythiourea-based block copolymer coating.
Further, the organic diamine is 3,3' diaminodiphenylmethane;
the amine-terminated oligomer is diamino polydimethylsiloxane;
the weak polar solvent is tetrahydrofuran;
the polar solvent is dimethylformamide or dimethylacetamide.
Further, in step 1), the ratio of 1, 4-benzenediisoisothiocyanate to the weakly polar solvent is 1mmol: (1-3) ml;
in step 2), the ratio of amine terminated oligomer to the less polar solvent was 1mmol: (1-10) ml;
in step 5), the ratio of polythiourea-based block copolymer product to polar solvent was 100mg: (0.5-2) ml.
Further, the molar ratio of the 1, 4-benzenediisocyanato ester, the organic diamine and the amine terminated oligomer is (1-1.05): x: (1-x), wherein x is 0.1-0.9.
Further, in the step 1), the reaction time is 1-2h under the condition of nitrogen and room temperature;
in the step 2), the heating temperature is 45-55 ℃ and the reaction time is 5-7h;
in step 4), the temperature at which the solvent is removed is room temperature for 12-14 hours.
Further, in the step 3), the semipermeable membrane filled with the polythiourea solution B is stirred and soaked in diethyl ether for 20-26 hours.
Further, in the filtering in the step 6), a filter membrane with a pore size of 0.45um is used.
Further, in the step 7), the specific gradient heating process is as follows: preserving heat for 1h-3h at 55-65 ℃, and preserving heat for 5h-7h at 75-85 ℃.
Further, step 8) is also included: and 7) heating the sample obtained in the step 7) in a vacuum environment to further remove the polar solvent, wherein the heating temperature is 90-100 ℃ and the heating time is 46-50 h.
A polythiourea-based block copolymer coating for improving the surface flashover voltage of epoxy resin is prepared by adopting the preparation method.
Compared with the prior art, the invention has the following beneficial technical effects:
in the process of generating the surface flashover, initial electrons generated from three binding points of a cathode-atmosphere-material impact the surface of the material under the action of an electric field to generate secondary electrons, part of the secondary electrons continuously impact the material to generate more secondary electrons, and finally, the electron avalanche of the stroke occurs, namely the surface flashover occurs. During this process, some of the electrons striking the surface of the material are trapped by traps in the material with a certain probability and cannot participate in the process of generating secondary electrons. The resistivity of the epoxy resin samples coated with the polythiourea segmented copolymer coatings with different proportions is higher than that of the pure epoxy resin, and the resistivity is continuously improved along with the increase of the content of the organic diamine. The increase of the resistivity indicates that the trap level or the trap density of the sample is increased, more charges in the material can be effectively captured, the collision ionization process in the occurrence of the surface flashover is helped to be blocked, and further, the material can bear higher voltage between electrodes before electrons form an electron avalanche, and further, the voltage of the occurrence of the surface flashover phenomenon is improved. The coating of the invention has low preparation process difficulty and strong reliability, and can be widely applied to the field of high-voltage insulating materials.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention.
FIG. 1 is a synthetic route diagram of a polythiourea-based block copolymer coating material.
FIG. 2 is a graph of N for an epoxy resin and a polythioureido block copolymer coating 2 A histogram of average values of 20 subsurface flashover voltages.
FIG. 3 is a volume resistivity histogram of an epoxy resin and an epoxy resin containing a polythiourea-based block copolymer coating.
Detailed Description
The present invention is explained in further detail below:
a preparation method of a polythiourea-based block copolymer coating for improving the surface flashover voltage of epoxy resin comprises the following steps:
1) 1, 4-benzene diisoisothiocyanate is completely dissolved in a weak polar solvent, then organic diamine is added, and the mixture reacts under the condition of nitrogen and room temperature to obtain a polythiourea solution A; and (3) completely dissolving the amine-terminated oligomer in a weak polar solvent, adding the solvent into the polythiourea solution A, and reacting under the condition of nitrogen and heating to obtain a polythiourea solution B. Wherein, the ratio of the 1, 4-benzene diisoisothiocyanate to the weak polar solvent is 1mmol:1-3ml; the organic diamine is 3,3' diaminodiphenyl methane; the amine-terminated oligomer is diamino polydimethylsiloxane; the ratio of 1, 4-benzenediisothiocyanate to 3,3' diaminodiphenylmethane and diaminopolydimethylsiloxane is from 1 to 1.05mmol: x mmol: (1-x) mmol, wherein x is 0.1-0.9. The ratio of amine terminated oligomer to the weak polar solvent was 1mmol:1-10ml; the weak polar solvent is Tetrahydrofuran (THF); the reaction time is 1-2h under the condition of nitrogen and room temperature; the heating temperature in the reaction is 45-55 ℃ under the condition of nitrogen and heating, and the reaction time is 6-7h.
2) And collecting the obtained polythiourea solution B into a semipermeable membrane, stirring and soaking the semipermeable membrane in diethyl ether, and removing unreacted 1, 4-benzene diisothiocyanate, organic diamine and amine-terminated oligomer to obtain a polythiourea-based block copolymer product. Wherein, stirring and soaking in diethyl ether for 20-26h.
3) The collected polythiourea-based block copolymer product was placed in a vacuum oven for vacuum treatment to remove the solvent, resulting in a solid polythiourea-based block copolymer. Wherein the temperature of the vacuum oven is room temperature and the time is 12-14h.
4) Placing the solid polythiourea-based block copolymer into a polar solution, adding magnetons, and stirring until the solid polythiourea-based block copolymer is completely dissolved; wherein the polar solvent is Dimethylformamide (DMF) or dimethylacetamide (DMAc).
5) After filtration, a clear polythiourea-based block copolymer solution was obtained; wherein the pore size of the filter membrane is 0.45um.
6) Placing epoxy resin on a constant temperature heating table, spreading a polythiourea-based block copolymer solution on the epoxy resin by adopting a tape casting method, and removing a polar solvent by adopting gradient heating, wherein the specific process of gradient heating is to keep the temperature at 55-65 ℃ for 1-3 h, and then keep the temperature at 75-85 ℃ for 5-7 h.
7) To further remove the polar solvent, the sample obtained in 6) is placed in a vacuum oven and heated in a vacuum environment to obtain an epoxy resin sample containing the polythiourea-based block copolymer coating. Wherein the temperature of the vacuum oven is 90-100 ℃ and the time is 46-50 h.
The invention is explained in further detail below in connection with the examples:
example 1
Epoxy resin sample containing coating with diaminodiphenyl methane ratio of 0.1 (noted as EP+SD 0.1)
Referring to the synthetic route diagram of the polythiourea-based block copolymer of FIG. 1, a method for preparing a polythiourea-based block copolymer coating for increasing the interfacial flashover voltage of an epoxy resin comprises the following steps;
1) 1mmol of 1, 4-benzene diisocyanato is completely dissolved in 1ml of tetrahydrofuran solvent, then 0.1mmol of 3,3' diaminodiphenyl methane is added, and the mixture is reacted for 1 hour under the condition of nitrogen and room temperature to obtain a polythiourea solution A. 0.9mmol of diaminopolydimethylsiloxane is completely dissolved in 1ml of tetrahydrofuran solvent, and then added into the polythiourea solution A to react for 6 hours in a nitrogen environment at 45 ℃ to obtain a polythiourea solution B.
2) And collecting the obtained polythiourea solution B into a semipermeable membrane, stirring and soaking the semipermeable membrane in diethyl ether for 20 hours, and removing unreacted monomers and oligomers to obtain a polythiourea-based block copolymer product.
3) The collected polythiourea-based block copolymer product was placed in a vacuum oven for vacuum treatment to remove the solvent, resulting in a solid polythiourea product. Wherein the temperature of the vacuum oven is room temperature and the time is 12h.
4) The polythioureido block copolymer product is placed in a polar solvent Dimethylformamide (DMF), and the magneton is added and stirred until the polythioureido block copolymer product is completely dissolved.
5) After filtration through a filter membrane having a pore size of 0.45. Mu.m, a clear polythiourea-based block copolymer solution was obtained.
6) Placing an epoxy resin sample on a constant temperature heating table, spreading the polythiourea-based block copolymer solution on the epoxy resin by adopting a tape casting method, and removing the polar solvent by adopting gradient heating. Wherein, the specific process of gradient temperature rise is that the temperature is kept at 60 ℃ for 2 hours, and then the temperature is kept at 80 ℃ for 6 hours.
7) To further remove the polar solvent, the samples were placed in a vacuum oven and heat treated in a vacuum environment to obtain epoxy samples containing ep+sd0.1 coating. Wherein the temperature of the vacuum oven is 100 ℃ and the time is 48 hours.
Example 2
Epoxy resin sample containing coating with diaminodiphenyl methane ratio of 0.5 (noted as EP+SD 0.5)
Referring to the synthetic route diagram of the polythiourea-based block copolymer of FIG. 1, a polythiourea-based block copolymer coating for increasing the interfacial flashover voltage of an epoxy resin and a method for preparing the same, comprising the steps of;
1) 1mmol of 1, 4-benzene diisocyanato was completely dissolved in 2ml of tetrahydrofuran solvent, then 0.5mmol of 3,3' diaminodiphenyl methane was added, and the mixture was reacted under nitrogen atmosphere at room temperature for 1.5 hours to obtain polythiourea solution A. 0.5mmol of diaminopolydimethylsiloxane is completely dissolved in 1ml of tetrahydrofuran solvent, and then added into the polythiourea solution A to react for 6.5 hours in a nitrogen environment at 50 ℃ to obtain the polythiourea solution B.
2) And collecting the obtained polythiourea solution B into a semipermeable membrane, stirring and soaking the semipermeable membrane in diethyl ether for 24 hours, and removing unreacted monomers and oligomers to obtain a polythiourea-based block copolymer product.
3) The collected polythiourea-based block copolymer product was placed in a vacuum oven for vacuum treatment to remove the solvent, resulting in a solid polythiourea product. Wherein the temperature of the vacuum oven is room temperature and the time is 13h.
4) The polythioureido block copolymer product is placed in a polar solvent Dimethylformamide (DMF), and the magneton is added and stirred until the polythioureido block copolymer product is completely dissolved.
5) After filtration through a filter membrane having a pore size of 0.45. Mu.m, a clear polythiourea-based block copolymer solution was obtained.
6) Placing an epoxy resin sample on a constant temperature heating table, spreading the polythiourea-based block copolymer solution on the epoxy resin by adopting a tape casting method, and removing the polar solvent by adopting gradient heating. Wherein, the specific process of gradient temperature rise is that the temperature is kept at 60 ℃ for 2 hours, and then the temperature is kept at 80 ℃ for 6 hours.
7) To further remove the polar solvent, the samples were placed in a vacuum oven and heat treated in a vacuum environment to obtain epoxy samples containing ep+sd 0.5 coating. Wherein the temperature of the vacuum oven is 100 ℃ and the time is 48 hours.
Example 3
Epoxy resin sample containing coating with diaminodiphenyl methane ratio of 0.9 (noted as EP+SD 0.9)
Referring to the synthetic route diagram of the polythiourea-based block copolymer of FIG. 1, a polythiourea-based block copolymer coating for increasing the interfacial flashover voltage of an epoxy resin and a method for preparing the same, comprising the steps of;
1) 1mmol of 1, 4-benzene diisocyanato was completely dissolved in 3ml of tetrahydrofuran solvent, then 0.9mmol of 3,3' diaminodiphenyl methane was added, and the mixture was reacted under nitrogen atmosphere at room temperature for 2 hours to obtain polythiourea solution A. 0.1mmol of diaminopolydimethylsiloxane was completely dissolved in 1ml of tetrahydrofuran solvent, and then added into the polythiourea solution A, and reacted for 7 hours under the condition of 55 ℃ in a nitrogen atmosphere, to obtain a polythiourea solution B.
2) And collecting the obtained polythiourea solution B into a semipermeable membrane, stirring and soaking the semipermeable membrane in diethyl ether for 26 hours, and removing unreacted monomers and oligomers to obtain a polythiourea-based block copolymer product.
3) The collected polythiourea-based block copolymer product was placed in a vacuum oven for vacuum treatment to remove the solvent, resulting in a solid polythiourea product. Wherein the temperature of the vacuum oven is room temperature and the time is 14h.
4) The polythioureido block copolymer product was placed in the polar solvent dimethylacetamide (DMAc), and the magneton was added and stirred until completely dissolved.
5) After filtration through a filter membrane having a pore size of 0.45. Mu.m, a clear polythiourea-based block copolymer solution was obtained.
6) Placing an epoxy resin sample on a constant temperature heating table, spreading the polythiourea-based block copolymer solution on the epoxy resin by adopting a tape casting method, and removing the polar solvent by adopting gradient heating. Wherein, the specific process of gradient temperature rise is that the temperature is kept at 60 ℃ for 2 hours, and then the temperature is kept at 80 ℃ for 6 hours.
7) To further remove the polar solvent, the samples were placed in a vacuum oven and heat treated in a vacuum environment to obtain epoxy samples containing ep+sd 0.9 coating. Wherein the temperature of the vacuum oven is 100 ℃ and the time is 48 hours.
Referring to FIG. 2, epoxy resin (EP) and epoxy resin containing polythiourea-based block copolymer coating are shown at N 2 Average of 20 times of the subsurface flashover voltage. The experiment of the surface flashover voltage adopts a direct current voltage source, finger-shaped electrodes (the electrode spacing is 5.3 mm) and the air pressure is 0.1MPa. Table 1 gives the epoxy resins and the epoxy resins containing the coating in N 2 The average value of the flashover voltage of the middle edge surface and the lifting proportion of the flashover voltage can reach 45 percent at most. The coating of the invention can effectively improve the N content of the epoxy resin 2 An in-plane flashover voltage in the environment.
TABLE 1 surface flashover Voltage and boost ratio
| EP | EP+SD 0.1 | EP+SD 0.5 | EP+SD 0.9 | |
| Flashover voltage | 11.18kV | 13.34kV | 15.96kV | 16.31kV |
| Lifting ratio | / | 19.3％ | 42.8％ | 45.9％ |
Referring to fig. 3, epoxy (EP) and epoxy bulk resistivity containing polythiourea-based block copolymer coating. The resistivity of the polythiourea-based segmented copolymer coating with different proportions is larger than that of the epoxy resin, so that the surface insulation performance of the epoxy resin is effectively improved, and the surface insulation performance of the epoxy resin can be further improved in N 2 An in-plane flashover voltage in the environment.
The polythiourea-based block copolymer coating provided by the invention can obviously improve the flashover voltage of epoxy resin. According to the invention, through preparing the polythiourea-based block copolymer coating with different proportions, the insulating property of the surface of the epoxy resin is improved, so that the surface flashover voltage of the epoxy resin is improved. The method can be widely applied to the field of high-voltage insulating materials.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention and not for limiting the scope of protection thereof, and although the present invention has been described in detail with reference to the above embodiments, it should be understood by those of ordinary skill in the art that: various changes, modifications, or equivalents may be made to the particular embodiments of the invention by those skilled in the art after reading the present disclosure, but such changes, modifications, or equivalents are within the scope of the invention as defined in the appended claims.
Claims (10)
1. The preparation method of the polythiourea-based block copolymer coating for improving the surface flashover voltage of the epoxy resin is characterized by comprising the following steps of:
1) Completely dissolving 1, 4-benzene diisoisothiocyanate in a weak polar solvent, then adding organic diamine, and reacting under the condition of nitrogen and room temperature to obtain a polythiourea solution A;
2) Completely dissolving amine-terminated oligomer in a weak polar solvent, adding the weak polar solvent into the polythiourea solution A, and reacting under the condition of nitrogen and heating to obtain a polythiourea solution B;
3) Collecting the obtained polythiourea solution B into a semipermeable membrane, stirring and soaking the semipermeable membrane in diethyl ether, and removing unreacted 1, 4-benzene diisothiocyanate, organic diamine and amine-terminated oligomer to obtain a polythiourea-based block copolymer product;
4) Removing the solvent from the polythiourea-based block copolymer product under vacuum conditions to obtain a solid polythiourea-based block copolymer;
5) Placing the solid polythiourea-based block copolymer in a polar solution, and stirring until the solid polythiourea-based block copolymer is completely dissolved;
6) Filtering the solution obtained in the step 5) to obtain a clear polythioureido block copolymer solution;
7) Spreading the polythiourea-based block copolymer solution on the epoxy resin heated at constant temperature, and removing the polar solvent by adopting gradient heating to obtain an epoxy resin sample containing the polythiourea-based block copolymer coating.
2. The method for preparing a polythiourea-based block copolymer coating for increasing the surface flashover voltage of an epoxy resin according to claim 1, wherein the organic diamine is 3,3' diaminodiphenylmethane;
the amine-terminated oligomer is diamino polydimethylsiloxane;
the weak polar solvent is tetrahydrofuran;
the polar solvent is dimethylformamide or dimethylacetamide.
3. The method for preparing the polythiourea-based block copolymer coating for improving the surface flashover voltage of an epoxy resin according to claim 1, wherein in the step 1), the ratio of 1, 4-benzenediisocyanato to the weak polar solvent is 1mmol: (1-3) ml;
in step 2), the ratio of amine terminated oligomer to the less polar solvent was 1mmol: (1-10) ml;
in step 5), the ratio of polythiourea-based block copolymer product to polar solvent was 100mg: (0.5-2) ml.
4. The method for preparing the polythiourea-based block copolymer coating for improving the surface flashover voltage of an epoxy resin according to claim 1, wherein the molar ratio of the 1, 4-benzenediisocyanato, the organic diamine and the amine terminated oligomer is (1-1.05): x: (1-x), wherein x is 0.1-0.9.
5. The method for preparing the polythiourea-based block copolymer coating for improving the surface flashover voltage of epoxy resin according to claim 1, wherein in the step 1), the reaction time is 1-2 hours under the condition of nitrogen and room temperature;
in the step 2), the heating temperature is 45-55 ℃ and the reaction time is 5-7h;
in step 4), the temperature at which the solvent is removed is room temperature for 12-14 hours.
6. The method for preparing the polythiourea-based block copolymer coating for improving the surface flashover voltage of epoxy resin according to claim 1, wherein in the step 3), the semipermeable membrane filled with the polythiourea solution B is stirred and soaked in diethyl ether for 20-26 hours.
7. The method for preparing the polythiourea-based block copolymer coating for improving the surface flashover voltage of epoxy resin according to claim 1, wherein in the step 6), a filter membrane with a pore size of 0.45um is adopted during the filtration.
8. The method for preparing the polythiourea-based block copolymer coating for improving the surface flashover voltage of epoxy resin according to claim 1, wherein in the step 7), the specific gradient heating process is as follows: preserving heat for 1h-3h at 55-65 ℃, and preserving heat for 5h-7h at 75-85 ℃.
9. The method for preparing the polythiourea-based block copolymer coating for improving the surface flashover voltage of an epoxy resin according to claim 1, further comprising the step of 8): and 7) heating the sample obtained in the step 7) in a vacuum environment to further remove the polar solvent, wherein the heating temperature is 90-100 ℃ and the heating time is 46-50 h.
10. A polythiourea-based block copolymer coating for increasing the interfacial flashover voltage of an epoxy resin, characterized in that it is prepared by the preparation method of any one of claims 1-9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311579687.4A CN117487128A (en) | 2023-11-23 | 2023-11-23 | Polythiourea-based block copolymer coating for improving epoxy resin surface flashover voltage and preparation method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311579687.4A CN117487128A (en) | 2023-11-23 | 2023-11-23 | Polythiourea-based block copolymer coating for improving epoxy resin surface flashover voltage and preparation method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117487128A true CN117487128A (en) | 2024-02-02 |
Family
ID=89676203
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311579687.4A Pending CN117487128A (en) | 2023-11-23 | 2023-11-23 | Polythiourea-based block copolymer coating for improving epoxy resin surface flashover voltage and preparation method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117487128A (en) |
-
2023
- 2023-11-23 CN CN202311579687.4A patent/CN117487128A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107353871B (en) | High-temperature-resistant bonding sealing silicone resin and preparation method thereof | |
| CN111334163A (en) | Solvent-free epoxy self-leveling antistatic finish paint and preparation method thereof | |
| CN111234424A (en) | Flaky boron nitride/polyvinylidene fluoride composite material and preparation method thereof | |
| CN111777801A (en) | Silicone rubber composite material for insulated cable and preparation method thereof | |
| CN110071328B (en) | Cross-linked modified polyethyleneimine solid electrolyte and application thereof | |
| CN117487128A (en) | Polythiourea-based block copolymer coating for improving epoxy resin surface flashover voltage and preparation method thereof | |
| CN115124838A (en) | Polysulfone/modified filler composite dielectric film material and preparation method thereof | |
| CN112143377A (en) | Corona-resistant coating for cable and preparation method thereof | |
| CN114316327B (en) | High-surface flashover electric pressure gas adsorption coating and preparation method thereof | |
| DE102014210613B4 (en) | Process for the production of spherical silicon-carbon nanocomposites | |
| CN114790324B (en) | Method for improving breakdown strength of aluminum oxide/epoxy resin composite material | |
| CN112898779B (en) | Recyclable self-repairing flexible compliant electrode and preparation method thereof | |
| KR20130081549A (en) | Composition of polymer electrolyte having excellent durability and stability in high temperature and lithium battery using the same | |
| CN105924975B (en) | Silicon rubber for prefabricated intermediate joint of direct-current ultrahigh-voltage crosslinked cable and preparation method | |
| CN106380603B (en) | Silicon resin containing double amino MQ and preparation method and application thereof | |
| CN110734643B (en) | Preparation method of rare earth doped modified polyimide film | |
| DE102022103582A1 (en) | ENHANCED POWER CYCLE CAPACITORS | |
| CN114149582A (en) | Novel efficient chelate antioxidant as well as preparation method and application thereof | |
| CN111584174A (en) | Laminated sheet type polymer static suppressor | |
| CN115806645B (en) | High-voltage-resistant insulating material and preparation method thereof | |
| KR101900483B1 (en) | Citral-based polymer containing sulfur and preparation method thereof | |
| CN114015019B (en) | Method for improving surface flashover voltage of epoxy resin insulating material | |
| CN117511208B (en) | Polyetherimide-based composite dielectric film material and preparation method thereof | |
| CN109735213B (en) | High-heat-dissipation graphene-based coating and preparation method thereof | |
| CN114231032A (en) | Silicone rubber insulating material, silicone rubber insulator, and preparation method and application thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |