A phenol-free polyamide self-adhesive paint for coating electromagnetic wire, a preparation method and application thereof

Abstract

The application discloses a phenol-free polyamide self-adhesive paint for electromagnetic wire coating and a preparation method and application thereof, and comprises a film forming substance and a solvent, wherein the film forming substance comprises aliphatic polyamide resin, bisphenol A epoxy resin, oil-soluble phenolic resin, leveling agent and release agent; and the solvent comprises phenylethanol, butanol, ethanol and propylene glycol methyl ether acetate (PMA). The product manufactured by the application has the advantages of low toxicity and low atmospheric emission pollution, good physical and chemical properties, stable storage characteristics, ideal coating performance, excellent bonding characteristics, moisture resistance, deformation resistance and the like, can greatly improve the occupational health hazards of wire coating operation, and can obtain a green electromagnetic wire product, and has wide market application value.

Description

TECHNICAL FIELD

[0001] The present application belongs to polyamide self-adhesive paint for electromagnetic wire coating, and particularly relates to a phenol-free polyamide self-adhesive paint for electromagnetic wire coating, a preparation method and application thereof. BACKGROUND

[0002] The self-adhesive paint for electromagnetic wire coating includes polyamide, epoxy, polyester, acetal and other special polymer materials, wherein the polyamide accounts for a large proportion due to excellent bonding strength and good thermal bonding performance, and is widely used in the coating and manufacturing of special motor winding wire of various electronic components (mobile phone wireless charging, voice coil and other products).

[0003] The polyamide self-adhesive paint can be divided into aliphatic polyamide and aromatic structure self-adhesive paint according to the molecular type, the aromatic nylon has high crystallinity and is used in a small amount for the adhesion of winding coils in high-heat and high-humidity environment, and most of them are aliphatic polyamide self-adhesive paint. Due to good solubility of phenolic / xylene solvents, the aliphatic polyamide is dissolved in phenolic / xylene organic solvents, which has become the most traditional and classic product manufacturing technology method of polyamide self-adhesive paint.

[0004] With the continuous improvement of environmental protection requirements of the society, high-toxicity and high-pollution products will be restricted in production and use. The high toxicity of phenol and the high pollution of benzene make the traditional self-adhesive paint manufacturing method not meet the current stringent environmental protection policy requirements. Therefore, it is particularly necessary to develop an environmentally friendly phenol / xylene-free polyamide self-adhesive paint for electromagnetic wire coating. SUMMARY

[0005] The present application provides a phenol-free polyamide self-adhesive paint for electromagnetic wire coating, which is a hot-bonding aliphatic polyamide self-adhesive paint for electromagnetic wire coating without methylphenol / dimethylbenzene component solvent system, which can not only meet the performance requirements of the self-adhesive paint for electromagnetic wire coating, but also has low toxicity, low pollution and other environmental protection characteristics.

[0006] The present application also provides a preparation method and application of the phenol-free polyamide self-adhesive paint for electromagnetic wire coating.

[0007] Technical solution: In order to achieve the above-mentioned purpose, the polyamide self-adhesive paint for phenol-free electromagnetic wire coating provided by the application comprises film forming substances and solvents, and the film forming substances comprise aliphatic polyamide resin, bisphenol A epoxy resin, oil-soluble phenolic resin, leveling agent and release agent; the solvents comprise phenethyl alcohol, butanol, ethanol and propylene glycol methyl ether acetate (PMA); the above-mentioned substances are in the following proportions by weight: 130 parts of aliphatic polyamide resin, 19.5-28.6 parts of bisphenol A epoxy resin, 23.4-32.5 parts of oil-soluble phenolic resin, 0.182-0.91 parts of leveling agent, 1.274-0.546 parts of release agent, 490-555 parts of phenethyl alcohol, 98-180 parts of butanol, 25-65 parts of ethanol and 82-139 parts of propylene glycol methyl ether acetate (PMA).

[0008] Among them, the aliphatic polyamide resin is aliphatic copolymer polyamide resin. For example, Shanghai Zhenwei ES-06, ES-03 and the like are used.

[0009] Among them, the bisphenol A type epoxy resin is a linear epoxy resin synthesized from bisphenol A and propylene oxide, and the melting point is 70-140 DEG C. For example, SM6101 and SM6104 of the Sanm Group, 0194 and 0197 of the Nantong Xingchen Group and the like are used.

[0010] Among them, the oil-soluble phenolic resin is an oil-soluble phenolic resin synthesized from t-butyl phenol formaldehyde in an acidic medium. For example, Xinxiang Boma Fengfan 2402 is used.

[0011] Among them, the leveling agent is a polyester modified polysiloxane heat-resistant leveling agent. For example, Levaslip 872 of the Haimiside Group is used.

[0012] Among them, the release agent is stearic acid amide. For example, the same kind of products of Nantong Ru Yisen and Jiangxi Zhilian are used.

[0013] The preparation method of the polyamide self-adhesive paint for phenol-free electromagnetic wire coating provided by the application comprises the following steps:

[0014] (1) the phenethyl alcohol, butanol, ethanol and propylene glycol methyl ether acetate (PMA) are taken in the proportions by weight, stirred uniformly, 55-76 parts of the above-mentioned mixed solvents are taken as B liquid, 24-33 parts are taken as C liquid, and the remaining mixed solvents are taken as A liquid;

[0015] (2) the A liquid is stirred, the aliphatic polyamide resin is added at room temperature and heated and stirred until the resin is completely dissolved into a uniform solution, and then the temperature is lowered and the solution is kept warm for standby;

[0016] (3) the B liquid is stirred, the bisphenol A epoxy resin is added at room temperature and heated and stirred to ensure that the bisphenol A epoxy resin is completely dissolved into a uniform solution, and then the temperature is lowered and the solution is kept warm for standby;

[0017] (4) stirring C liquid, adding oil-soluble phenolic resin at room temperature, heating and stirring until fully dissolved into a uniform liquid, cooling, and keeping warm for standby;

[0018] (5) adding the bisphenol A epoxy resin solution prepared in step (3) and the oil-soluble phenolic resin solution prepared in step (4) into the polyamide resin solution prepared in step (2) in sequence, keeping warm and stirring, then adding leveling agent and release agent, and continuing to keep warm and stirring;

[0019] (6) filtering to obtain the finished product.

[0020] In step (2), the heating and stirring is at a temperature of 85±5℃, and the stirring and keeping warm is for 2-3h. In step (3), the heating and stirring is to raise the temperature to 65±5℃, keeping warm and stirring for 1.5-2h, and then lowering the temperature to 35±5℃, keeping warm for standby. In step (4), the heating and stirring is to raise the temperature to 75±5℃, keeping warm and stirring for 1.5-2h, and then lowering the temperature to 35±5℃, keeping warm for standby.

[0021] In step (4), the polyamide resin solution prepared in step (2) is cooled to 40±5℃, the bisphenol A epoxy resin solution prepared in step (3) and the oil-soluble phenolic resin solution prepared in step (4) are added in sequence, keeping warm and stirring at 40±5℃ for 1-2h, then adding leveling agent and release agent, and keeping warm and stirring at 40±5℃ for 1-2h.

[0022] As preferred, the preparation of the self-adhesive paint comprises the following steps:

[0023] (1) taking 490-555 parts by mass of phenethyl alcohol, 98-180 parts of butanol, 25-65 parts of ethanol, and 82-139 parts of propylene glycol methyl ether acetate (PMA), stirring uniformly, taking 55-76 parts of the above-mentioned mixed solvent (remark B liquid), 24-33 parts (remark C liquid) for standby, and the rest of the mixed solvent is called A liquid;

[0024] (2) adding the mixed solvent (A liquid) into a reaction kettle, starting stirring, adding 130 parts of aliphatic polyamide resin at room temperature, and starting to raise the temperature, and keeping warm and stirring at 85±5℃ for 2-3h until the resin is fully dissolved into a uniform solution;

[0025] (3) adding the mixed solvent B liquid taken out in step 1 into the reaction kettle, starting stirring, adding 19.5-28.6 parts by mass of bisphenol A epoxy resin, raising the temperature to 65±5℃, keeping warm and stirring for 1.5-2h to ensure that it is fully dissolved into a uniform solution, and then lowering the temperature to 35±5℃, keeping warm for standby;

[0026] (4) Add the mixed solvent C liquid taken out in step (1) into the reaction vessel, start stirring, add 23.4 to 32.5 parts by mass of oil-soluble phenolic resin, heat to 75±5℃, keep warm and stir for 1.5 to 2 hours until fully dissolved into a uniform liquid, cool down to 35±5℃, and keep warm for later use.

[0027] (5) Cool the polyamide resin solution prepared in step (2) to 40±5℃, and add the bisphenol A epoxy resin solution prepared in step (3) and the oil-soluble phenolic resin solution prepared in step (4) in sequence. Keep the solution at 40±5℃ and stir for 1 hour. Then add 0.182 to 0.91 parts of 872# leveling agent and 1.274 to 0.546 parts of release agent (stearamide) according to the mass ratio. Keep the solution at 40±5℃ and stir for 1 hour.

[0028] (6) Samples were taken to test viscosity and solid content, and filtered through a 250-mesh stainless steel filter (P≤0.4Mpa) to obtain the final product.

[0029] The application of the phenol-free polyamide self-adhesive varnish for coating electromagnetic wires described in this invention in green electromagnetic wire products.

[0030] The polyamide resin in this invention has an asymmetric long carbon chain molecular structure. Polyamide dissolves in strongly polar solvents or solutions that readily form hydrogen bonds with amide groups. Therefore, polar solvents are typically used as the main solvent. Strongly polar solvents at room temperature (such as phenols, sulfuric acid, formic acid, etc.), solutions of certain salts (such as a methanol solution saturated with calcium chloride, potassium thiocyanate, etc.), and solutions of ethylene glycol, chloroethanol, propylene glycol, and zinc chloride in methanol at high temperatures can dissolve polyamide. The principles for selecting and matching solvents are: 1. Similar polarity principle: highly polar solutes dissolve in highly polar solvents, and less polar solutes dissolve in less polar solvents; 2. Solvation principle: if the polymer molecule contains a large number of electrophilic groups, it can dissolve in solvents containing electron-bearing groups, and vice versa; 3. Similar cohesive energy density principle: if the cohesive energy density of the polymer and the solvent are similar, they are easily soluble; otherwise, they are insoluble or difficult to dissolve.

[0031] The polyamide self-adhesive paint prepared by the present application is used for coating self-adhesive electromagnetic wire. In addition to solubility, the selection of solvent also needs to consider the step evaporation temperature of the solvent. After evaporation, the solvent is catalytically combusted in the oven to form a secondary heat source, which promotes the crosslinking and curing of the main film-forming resin and the modified resin. The coating process adopts a thin coating multi-pass production method. The paint liquid is coated on the surface of the wire. As the wire runs, the temperature in the oven increases from low to high, and the solvent in the paint film is uniformly cured to obtain a good surface quality, which is beneficial to the improvement of the roundness of the finished wire. However, the solvent in the paint film cannot be completely evaporated, and a certain amount of residual solvent is required. On the one hand, it plays a lubricating role, and on the other hand, the paint film remains active, which is beneficial to the secondary processing of the wound coil. The processing of hot-melt self-adhesive electromagnetic wire is carried out through automatic winding equipment. The wire is rotated at high speed by the motor, and the specified shape is formed on the mold. At the same time, the oven gun heats the coil at high temperature, so that the self-adhesive layer on the surface of the wire melts, and the self-adhesive enameled wire coil is formed after the composite coating. The turns are firmly bonded together. Due to the heating of the composite coating self-adhesive enameled wire, the outer coating layer can be well melted and cured, the inter-turn adhesive layer penetrates and interacts with each other, so that the outer surface of the wire is covered with a large amount of adhesive layer, and there is no obvious adhesive interface between the wires. This also reduces the stress concentration at the adhesive position between the wires, thereby enhancing the adhesive strength. The boneless coil wound by the self-adhesive enameled wire forms a hard and complete solid body after curing. As can be seen from the cross-sectional micrograph, when the wires are in close contact, the adhesion is excellent. At the same time, the coil and the mold are easily separated, and the adhesive layer does not remain on the surface of the mold, which is beneficial to continuous production.

[0032] Cresol is a main solvent variety of traditional electromagnetic wire coating materials. Its strong solubility, stable evaporation characteristics and high heat value of combustion, low cost and easy to obtain (petroleum chemical industry, coal chemical industry refining), its role is not only as a solvent, but also improves the leveling performance of the paint liquid. It has been applied to the production of polyamide self-adhesive coating materials for a long time and cannot be replaced. Due to the high toxicity and strong corrosiveness of cresol, it causes environmental pollution and occupational health hazards to operators during the production and use of polyamide coating materials. The residual cresol in the coil gradually volatilizes, which produces an odor and poses a latent health hazard to the human body.

[0033] The selection of environmentally friendly solvents such as cresol and other harmful substances for source substitution is a technical subject that has been researched and solved by self-adhesive coating material production enterprises for a long time. However, based on the above technical reasons, especially the self-adhesive performance of the paint film, if cresol is not used and the type and proportion of environmentally friendly solvents are not properly selected, it cannot be properly solved.

[0034] The present application solves the problems of solubility, solvent step evaporation characteristics, coating performance, stability and the like without using cresol by selecting specific raw material composition and according to special manufacturing process, and the adhesion of the prepared wire is improved, and the like. Specifically, the phenol-free electromagnetic wire coating polyamide self-sticking paint prepared by the present application does not contain harmful substances such as cresol, and is more green and environmentally friendly; cresol has carcinogens such as polycyclic aromatic hydrocarbons in the extraction process, and the production of cresol cannot be recycled due to the depletion of petrochemical resources; the environmentally friendly material used in the present application is obtained by artificial synthesis, has high purity, and does not have the risk of resource depletion; phenolic and benzene substances will produce black smoke in the catalytic combustion process due to the benzene ring structure, and are not easy to recycle and harmlessly disposed, have high tail gas disposal cost, and have an impact on the surrounding environment, and the use of environmentally friendly phenol-free coating materials has no such impact; the product meets the regulations and standards of countries such as the European Union and the United States for limiting harmful substances, helps downstream coil, electromechanical and digital product manufacturing enterprises to break through the technical barriers of the industrial chain, and reduces the environmental protection cost of electromagnetic wire production enterprises. The coating material prepared by the present application has water and carbon dioxide as by-products after catalytic combustion. Phenolic and benzene substances need to consume more energy to obtain a large amount of external energy for cracking due to the benzene ring structure.

[0035] In the prior art, due to the compatibility of phenolic / xylene solvents, aliphatic polyamide is usually dissolved in phenolic / xylene organic solvents, and the phenol-free electromagnetic wire coating polyamide self-sticking paint prepared by the present application first uses modified alcohol solvents to replace the traditional cresol / xylene solvent system, greatly reduces occupational health hazards and air emission pollution, but the replacement of the solvent will lead to the reduction of the performance of the self-sticking paint, and the specific design of the solvent in the present application not only ensures the environmental protection, but also ensures the performance of the self-sticking paint; at the same time, the aliphatic copolymer polyamide resin is used as the main film-forming material, and has excellent compatibility with the mixed solvent in the formula. Further, the present application uses bisphenol A epoxy resin which is compatible with the solvent system and can match the main film-forming polyamide resin, to improve the disadvantages of polyamide resin being easy to absorb moisture and sticky, and improve the mechanical properties and chemical resistance of the electromagnetic wire winding.

[0036] The specific method of the present application prepares a new phenol-free electromagnetic wire coating polyamide self-sticking paint, which has good physical and chemical properties, stable storage characteristics, ideal coating performance and excellent adhesion characteristics, is resistant to wetting and deformation, has excellent environmental protection, and can greatly reduce occupational health hazards and environmental pollution.

[0037] Advantages: Compared with the prior art, the advantages of the present application are:

[0038] 1. The present application prepares a phenol-free polyamide self-adhesive paint for electromagnetic wire coating, which uses an environmentally friendly solvent to replace methylphenol and benzene in traditional self-adhesive coating materials, eliminating the harmfulness and biological toxicity of self-adhesive coating materials, and having no corrosive harm to human skin and mucous membrane tissues.

[0039] 2. The phenol-free polyamide self-adhesive paint for electromagnetic wire coating prepared by the present application significantly improves the working environment of the production and use area, has no foul odor of methylphenol, and relieves the discomfort of the human body.

[0040] 3. The product manufactured by the present application has low toxicity and low atmospheric emission pollution without phenol (methylphenol / phenol), and has good physical and chemical properties, stable storage characteristics, ideal coating performance, excellent bonding characteristics, resistance to moisture, deformation resistance and other characteristics, which can greatly improve the occupational health hazards of wire coating operation, obtain green electromagnetic wire products, and have wide market application value. DETAILED DESCRIPTION

[0041] The present application is further described below in conjunction with examples.

[0042] The raw materials and reagents used in the examples are all commercially available. The seed cells are all obtained by existing conventional separation and purification methods or directly commercially available.

[0043] The following raw materials are used in the examples:

[0044] The aliphatic polyamide resin is Shanghai Zhenwei ES-06.

[0045] The bisphenol A type epoxy resin is Sanmou Group SM6101.

[0046] The oil-soluble phenolic resin is Xinxiang Boma Wind Sail 2402.

[0047] The leveling agent is Haimisidexun Levaslip 872.

[0048] The release agent is stearic acid amide produced by Jiangxi Zhilian.

[0049] Example 1

[0050] The weight parts of each substance are calculated in each step

[0051] 1. Take 490 parts of phenylethanol, 180 parts of butanol, 65 parts of ethanol, 82 parts of propylene glycol methyl ether acetate (PMA), stir uniformly, take 55 parts of the above-mentioned mixed solvent (remark B liquid), 24 parts (remark C liquid) for standby, and the remaining mixed solvent is called A liquid;

[0052] 2. The mixed solvent (A liquid) is added to the reaction kettle, the stirring is started, the aliphatic polyamide resin 130 parts is put in at room temperature, the temperature is started to rise, and the stirring is kept at 85°C for 2 hours until the resin is completely dissolved into a uniform solution;

[0053] 3. The mixed solvent B liquid taken out in step 1 is put into the reaction kettle, the stirring is started, 28.6 parts of bisphenol A epoxy resin is put in, the temperature is raised to 65°C, the stirring is kept for 1.5 hours to ensure that it is completely dissolved into a uniform solution, and the temperature is lowered to 35°C for standby;

[0054] 4. The mixed solvent C liquid taken out in step 1 is put into the reaction kettle, the stirring is started, 23.4 parts of oil-soluble phenolic resin is put in, the temperature is raised to 75°C, the stirring is kept for 1.5 hours until it is completely dissolved into a uniform liquid, and the temperature is lowered to 35°C for standby;

[0055] 5. The polyamide resin solution prepared in step 2 is cooled to 40°C, the bisphenol A epoxy resin solution prepared in step 3 and the oil-soluble phenolic resin solution prepared in step 4 are put in in sequence, the stirring is kept at 40°C for 1 hour, then 0.182 parts of leveling agent and 1.274 parts of release agent are added according to the mass ratio, and the stirring is kept at 40°C for 1 hour;

[0056] 6. The viscosity and solid content are tested, it is filtered through a 250-mesh stainless steel filter (P≤0.4Mpa), and finally the finished product is prepared.

[0057] Example 2

[0058] 1. 515 parts of phenethyl alcohol, 147 parts of butanol, 49 parts of ethanol, and 106 parts of propylene glycol methyl ether acetate (PMA) are taken according to the mass fraction, stirred uniformly, 61 parts (remark B liquid) and 26 parts (remark C liquid) of the above-mentioned mixed solvent are taken for standby, and the remaining mixed solvent is called A liquid;

[0059] 2. The mixed solvent (A liquid) is added to the reaction kettle, the stirring is started, the aliphatic polyamide resin 130 parts is put in at room temperature, the temperature is started to rise, and the stirring is kept at 85°C for 3 hours until the resin is completely dissolved into a uniform solution;

[0060] 3. The mixed solvent B liquid taken out in step 1 is put into the reaction kettle, the stirring is started, 26 parts of bisphenol A epoxy resin is put in, the temperature is raised to 65°C, the stirring is kept for 2 hours to ensure that it is completely dissolved into a uniform solution, and the temperature is lowered to 35°C for standby;

[0061] 4, Put the mixed solvent C liquid taken out in step 1 into the reaction kettle, start stirring, put in 26 parts by mass of oil-soluble phenolic resin, heat to 75℃, keep stirring for 2h until fully dissolved into a uniform liquid, cool to 35℃, keep ready for use;

[0062] 5, The polyamide resin solution prepared in step 2 is cooled to 40℃, and the bisphenol A epoxy resin solution prepared according to step 3 and the oil-soluble phenolic resin solution prepared according to step 4 are sequentially added, and stirred at 40℃ for 1h, then 0.364 parts by mass of leveling agent and 1.092 parts by mass of release agent are added, and stirred at 40℃ for 1h;

[0063] 6, Sample test viscosity, solid content, filter through a 250 mesh stainless steel filter (P≤0.4Mpa), finally obtain the finished product.

[0064] Example 3

[0065] 1, Take 531 parts by mass of phenethyl alcohol, 122 parts by mass of butanol, 41 parts by mass of ethanol, and 123 parts by mass of propylene glycol methyl ether acetate (PMA), stir uniformly, take 66 parts by mass of the above mixed solvent (remark B liquid), 29 parts by mass (remark C liquid) for standby, and the remaining mixed solvent is called A liquid;

[0066] 2, Put the mixed solvent (A liquid) into the reaction kettle, start stirring, add 130 parts of aliphatic polyamide resin at room temperature, and start heating, and stir at 85℃ for 2.5h until the resin is fully dissolved into a uniform solution;

[0067] 3, Put the mixed solvent B liquid taken out in step 1 into the reaction kettle, start stirring, add 23.4 parts by mass of bisphenol A epoxy resin, heat to 65℃, keep stirring for 2h to ensure that it is fully dissolved into a uniform solution, cool to 35℃, keep ready for use;

[0068] 4, Put the mixed solvent C liquid taken out in step 1 into the reaction kettle, start stirring, put in 28.6 parts by mass of oil-soluble phenolic resin, heat to 75℃, keep stirring for 2h until fully dissolved into a uniform liquid, cool to 35℃, keep ready for use;

[0069] 5, The polyamide resin solution prepared in step 2 is cooled to 40℃, and the bisphenol A epoxy resin solution prepared according to step 3 and the oil-soluble phenolic resin solution prepared according to step 4 are sequentially added, and stirred at 40℃ for 1h, then 0.728 parts by mass of leveling agent and 0.728 parts by mass of release agent are added, and stirred at 40℃ for 1h;

[0070] 6, Sample test viscosity, solid content, filter through a 250 mesh stainless steel filter (P≤0.4Mpa), finally obtain the finished product.

[0071] Example 4

[0072] 1. Take phenyl ethanol 555 parts, butanol 180 parts, ethanol 25 parts, propylene glycol methyl ether acetate (PMA) 139 parts by mass, stir evenly, take the above mixed solvent 76 parts (remark B liquid), 33 parts (remark C liquid) for standby, the remaining mixed solvent is called A liquid;

[0073] 2. Add the mixed solvent (A liquid) to the reaction kettle, start stirring, and put in 130 parts of aliphatic polyamide resin at room temperature, and start heating, and stir at 85°C for 2.5h until the resin is completely dissolved into a uniform solution;

[0074] 3. Put the mixed solvent B liquid taken out in step 1 into the reaction kettle, start stirring, put in 19.5 parts of bisphenol A epoxy resin by mass, heat to 65°C, and stir for 1.5h to ensure that it is fully dissolved into a uniform solution, and then cool to 35°C for standby;

[0075] 4. Put the mixed solvent C liquid taken out in step 1 into the reaction kettle, start stirring, put in 32.5 parts of oil-soluble phenolic resin by mass, heat to 75°C, and stir for 1.5h until it is fully dissolved into a uniform liquid, and then cool to 35°C for standby;

[0076] 5. Cool the polyamide resin solution prepared in step 2 to 40°C, and then sequentially add the bisphenol A epoxy resin solution prepared in step 3 and the oil-soluble phenolic resin solution prepared in step 4, and stir at 40°C for 1h, and then add 0.91 parts of leveling agent and 0.546 parts of release agent by mass, and stir at 40°C for 1h;

[0077] 6. Take samples to test viscosity and solid content, filter through a 250 mesh stainless steel filter (P≤0.4Mpa), and finally obtain the finished product.

[0078] Comparative Example 1

[0079] 1. Take phenyl ethanol 555 parts, butanol 180 parts, ethanol 25 parts, propylene glycol methyl ether acetate (PMA) 139 parts by mass, stir evenly, take the above mixed solvent 76 parts (remark B liquid), 33 parts (remark C liquid) for standby, the remaining mixed solvent is called A liquid;

[0080] 2. Add the mixed solvent (A liquid) to the reaction kettle, start stirring, and put in 130 parts of aliphatic polyamide resin at room temperature, and start heating, and stir at 85°C for 2.5h until the resin is completely dissolved into a uniform solution;

[0081] 3, the mixed solvent B liquid taken out in step 1 is put into the reaction kettle, the stirring is started, 23.4 parts by mass of bisphenol A epoxy resin is put in, the temperature is raised to 65 DEG C, the temperature is kept for 2h, and it is ensured that it is fully dissolved into a uniform solution, the temperature is lowered to 35 DEG C, and it is kept for standby;

[0082] 4, the mixed solvent C liquid taken out in step 1 is put into the reaction kettle, the stirring is started, 28.6 parts by mass of oil-soluble phenolic resin is put in, the temperature is raised to 75 DEG C, the temperature is kept for 2h, and it is fully dissolved into a uniform liquid, the temperature is lowered to 35 DEG C, and it is kept for standby;

[0083] 5, the polyamide resin solution prepared in step 2 is cooled to 40 DEG C, the bisphenol A epoxy resin solution prepared according to step 3 and the oil-soluble phenolic resin solution prepared according to step 4 are sequentially put in, and the temperature is kept for 1h under the temperature of 40 DEG C;

[0084] 6, the viscosity and solid content are tested, it is filtered through a 250 mesh stainless steel filter screen (P≤0.4Mpa), and finally the finished product is prepared.

[0085] Comparative example 2

[0086] 1, 327 parts by mass of phenethyl alcohol, 41 parts by mass of butanol, 81 parts by mass of ethanol, and 368 parts by mass of propylene glycol methyl ether acetate (PMA) are taken, and they are uniformly stirred, 30 parts (remark B liquid) and 91 parts (remark C liquid) of the above mixed solvents are taken for standby, and the remaining mixed solvent is called A liquid;

[0087] 2, the mixed solvent (A liquid) is added into the reaction kettle, the stirring is started, 130 parts by mass of aliphatic polyamide resin is put in at room temperature, the temperature is raised, and the temperature is kept for 3h under the temperature of 85 DEG C, until the resin is fully dissolved into a uniform solution;

[0088] 3, the mixed solvent B liquid taken out in step 1 is put into the reaction kettle, the stirring is started, 26 parts by mass of bisphenol A epoxy resin is put in, the temperature is raised to 65 DEG C, the temperature is kept for 2h, and it is ensured that it is fully dissolved into a uniform solution, the temperature is lowered to 35 DEG C, and it is kept for standby;

[0089] 4, the mixed solvent C liquid taken out in step 1 is put into the reaction kettle, the stirring is started, 26 parts by mass of oil-soluble phenolic resin is put in, the temperature is raised to 75 DEG C, the temperature is kept for 2h, and it is fully dissolved into a uniform liquid, the temperature is lowered to 35 DEG C, and it is kept for standby;

[0090] 5, the polyamide resin solution prepared in step 2 is cooled to 40 DEG C, the bisphenol A epoxy resin solution prepared according to step 3 and the oil-soluble phenolic resin solution prepared according to step 4 are sequentially put in, and the temperature is kept for 1h under the temperature of 40 DEG C, then 0.364 parts by mass of leveling agent and 1.092 parts by mass of release agent are added, and the temperature is kept for 1h under the temperature of 40 DEG C;

[0091] 6. Sample test viscosity, solid content, filter through 250 mesh stainless steel screen (P≤0.4Mpa), and finally produce finished product.

[0092] Physicochemical detection and coated wire of the above examples 1-4 and comparative examples 1-2 Performance test, results as shown in Table 1.

[0093] Table 1 Performance test of self-adhesive paint

[0094]

[0095]

[0096] Physicochemical parameter test standard reference of self-adhesive paint: JB / T 7599.1-2013 Insulating paint for enameled round winding wire, Part 12: Polyamide self-adhesive enameled wire paint

[0097] Self-adhesive electromagnetic wire test standard reference: GB / T 6109.8-2008 Insulating paint for enameled round winding wire, Part 8: Hot-bonding or solvent-bonding polyester enameled round copper wire

[0098] Through the product self-adhesive paint and coated electromagnetic wire detection:

[0099] 1. The new type of environmentally friendly phenol-free polyamide electromagnetic wire coating self-adhesive paint manufactured in examples 1-4, the physicochemical parameters and the performance of the coated electromagnetic wire meet the technical target value requirements, meet the requirements of JB / T 7599.1-2013 Insulating paint for enameled round winding wire, Part 12: Polyamide self-adhesive enameled wire paint and GB / T 6109.8-2008 Insulating paint for enameled round winding wire, Part 8: Hot-bonding or solvent-bonding polyester enameled round copper wire national standards, and has the remarkable characteristics of phenol-free, low toxicity, environmental protection, etc.

[0100] 2. Use excess bisphenol A epoxy resin and new type of environmentally friendly solvent to match, the finished product is opaque, and affects the surface quality of the finished product and the wire, so the appropriate dosage should be selected within the appropriate limit;

[0101] 3. The appropriate addition of leveling agent and release agent helps to obtain good wire paint film surface quality, and has anti-wetting characteristics;

[0102] 4. In order to obtain good coating stability of polyamide resin, the solvent components and proportion must be designed reasonably, otherwise the solubility and storage stability will be affected.

[0103] Among them, the comparative example refers to example 2, and the solvent ratio is changed, and other conditions remain unchanged, which shows that the inappropriate solvent ratio matching parameter will change the solubility, resulting in gel of the paint liquid finished product, and the product is not storage-resistant.

[0104] Further, the effects of the addition amounts of the four different solvents phenylethanol, butanol, ethanol, and propylene glycol methyl ether acetate (PMA) in the present application on the finished product are compared.

[0105] Comparative Example 3 is the same as the method of Example 2, except that the phenylethanol is 480 parts.

[0106] Comparative Example 4 is the same as the method of Example 2, except that the phenylethanol is 565 parts.

[0107] Comparative Example 5 is the same as the method of Example 2, except that the butanol is 90 parts.

[0108] Comparative Example 6 is the same as the method of Example 2, except that the butanol is 190 parts.

[0109] Comparative Example 7 is the same as the method of Example 2, except that the ethanol is 15 parts.

[0110] Comparative Example 8 is the same as the method of Example 2, except that the ethanol is 75 parts.

[0111] Comparative Example 9 is the same as the method of Example 2, except that the propylene glycol methyl ether acetate is 70 parts.

[0112] Comparative Example 10 is the same as the method of Example 2, except that the propylene glycol methyl ether acetate is 150 parts.

[0113] According to the above-mentioned physical and chemical parameter test standards for the self-adhesive paint, the products prepared in Comparative Examples 3-10 all cause a certain degree of gelation, and the products are not storage-resistant and will freeze within 30 days, further indicating that the composition of the specific solvents in the present application, too much or too little, will cause changes in the performance of the finished product.

Claims

1. A phenol-free polyamide self-adhesive paint for coating of electromagnetic wire, characterized in that, The film-forming material includes aliphatic polyamide resin, bisphenol A epoxy resin, oil-soluble phenolic resin, leveling agent, and release agent; the solvent includes phenethyl alcohol, butanol, ethanol, and propylene glycol methyl ether acetate (PMA); the above-mentioned substances are in the following proportions by weight: aliphatic polyamide resin 130 parts, bisphenol A epoxy resin 19.5-28.6 parts, oil-soluble phenolic resin 23.4-32.5 parts, leveling agent 0.182-0.91 parts, release agent 1.274-0.546 parts, phenethyl alcohol 490-555 parts, butanol 98-180 parts, ethanol 25-65 parts, and propylene glycol methyl ether acetate (PMA) 82-139 parts. The preparation method of the phenol-free type electromagnetic wire coating polyamide self-adhesive paint comprises the following steps: (1) take phenethyl alcohol, butanol, ethanol, and propylene glycol methyl ether acetate (PMA) by weight, stir them uniformly, take 55-76 parts of the above-mentioned mixed solvent as B liquid, 24-33 parts as C liquid, and the rest of the mixed solvent as A liquid; (2) stir A liquid, add aliphatic polyamide resin at room temperature, heat and stir until the resin is completely dissolved into a uniform solution, cool down, and keep warm for standby; (3) stir B liquid, add bisphenol A epoxy resin at room temperature, heat and stir to ensure that it is completely dissolved into a uniform solution, cool down, and keep warm for standby; (4) stir C liquid, add oil-soluble phenolic resin at room temperature, heat and stir until it is completely dissolved into a uniform liquid, cool down, and keep warm for standby; (5) add the bisphenol A epoxy resin solution prepared in step (3) and the oil-soluble phenolic resin solution prepared in step (4) to the polyamide resin solution prepared in step (2) in sequence, stir and keep warm, then add leveling agent and release agent, and continue to stir and keep warm; (6) filter to obtain the finished product.

2. The phenol-free polyamide self-bonding paint for coating of electromagnetic wire according to claim 1, characterized by, The bisphenol A type epoxy resin is a linear epoxy resin synthesized from bisphenol A and propylene oxide, with a melting point of 70-140℃.

3. The phenol-free polyamide self-bonding paint for coating of electromagnetic wire according to claim 1, characterized by, The oil-soluble phenolic resin is an oil-soluble phenolic resin synthesized from tert-butyl phenol formaldehyde in an acidic medium.

4. The phenol-free polyamide self-bonding paint for coating of electromagnetic wire according to claim 1, characterized by, The leveling agent is a polyester-modified polysiloxane heat-resistant leveling agent.

5. The phenol-free polyamide self-bonding paint for coating of electromagnetic wire according to claim 1, characterized by, The release agent is stearic acid amide.

6. A process for the preparation of a phenol-free polyamide self-bonding paint for the coating of electromagnetic wires according to claim 1, characterized by the fact that, The preparation method comprises the following steps: (1) take phenethyl alcohol, butanol, ethanol, and propylene glycol methyl ether acetate (PMA) by weight, stir them uniformly, take 55-76 parts of the above-mentioned mixed solvent as B liquid, 24-33 parts as C liquid, and the rest of the mixed solvent as A liquid; (2) stir A liquid, add aliphatic polyamide resin at room temperature, heat and stir until the resin is completely dissolved into a uniform solution, cool down, and keep warm for standby; (3) stir B liquid, add bisphenol A epoxy resin at room temperature, heat and stir to ensure that it is completely dissolved into a uniform solution, cool down, and keep warm for standby; (4) stir C liquid, add oil-soluble phenolic resin at room temperature, heat and stir until it is completely dissolved into a uniform liquid, cool down, and keep warm for standby; (5) The polyamide resin solution prepared in step (2) is sequentially added with the bisphenol A epoxy resin solution prepared in step (3) and the oil-soluble phenolic resin solution prepared in step (4), and after stirring and heat preservation, a leveling agent and a release agent are added, and stirring and heat preservation are continued; (6) The final product is obtained after filtration.

7. The production method according to claim 6, wherein The heating and stirring in step (2) is carried out at a temperature of 85±5℃ for 2-3h; the heating and stirring in step (3) is heating to 65±5℃, stirring and heat preservation for 1.5-2h, cooling to 35±5℃, and heat preservation for standby; the heating and stirring in step (4) is heating to 75±5℃, stirring and heat preservation for 1.5-2h, cooling to 35±5℃, and heat preservation for standby.

8. The preparation method according to claim 6, characterized in that, In step (5), the polyamide resin solution prepared in step (2) is cooled to 40±5℃, and the bisphenol A epoxy resin solution prepared in step (3) and the oil-soluble phenolic resin solution prepared in step (4) are sequentially added, and stirring and heat preservation are carried out at 40±5℃ for 1-2h, and then a leveling agent and a release agent are added, and stirring and heat preservation are carried out at 40±5℃ for 1-2h.

9. Use of the phenol-free polyamide self-adhesive paint for coating electromagnetic wire according to claim 1 in electromagnetic wire products.

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