Airing type composite vegetable oleic acid modified heat-resistant polyester resin and preparation method thereof
By introducing composite vegetable oleic acid modified heat-resistant polyester resin into the insulating varnish, the problem of difficult drying of traditional insulating varnish at room temperature is solved, efficient room temperature drying and excellent insulation performance are achieved, and are suitable for large and medium-sized motor and electrical equipment.
Patent Information
- Application Number
- CN202510304901.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-14
- Publication Date
- 2025-05-30
AI Technical Summary
Traditional insulating varnish is difficult to dry at room temperature when applied to large motor and electrical equipment and insulated parts that are not easy to bake, resulting in poor insulation performance and coating quality.
The dry-type composite vegetable oleic acid-modified heat-resistant polyester resin is adopted. The preparation method includes mixing and stirring isocyanurate-type saturated polyester resin, composite vegetable oleic acid and other components, and modifying the resin by introducing composite vegetable oleic acid to achieve room temperature drying.
This method not only enhances the flexibility of the paint film and room temperature drying ability, but also improves the electrical insulation, heat resistance and mechanical strength of the coating, meeting the strict requirements of insulated parts by large and medium-sized motor and electrical equipment.
Smart Images
Figure CN120059567A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of insulating paint resins, and relates to an air-drying type composite vegetable oil acid modified heat-resistant polyester resin and a preparation method thereof. Background Art
[0002] As an important electrical engineering material, insulating varnish plays a crucial role in the manufacturing and maintenance of motor and electrical appliance coils. Such materials mainly use high molecular polymers as the matrix. Through specific formulation design, they can penetrate and fill the gaps and micropores inside the motor and electrical appliance coils, thereby significantly improving the insulation performance and structural strength of the coils. When the insulating varnish is baked and cured at a specific temperature, it can form a continuous, flat and transparent insulating coating on the surface of the impregnated object. This coating not only has excellent electrical insulation performance, but also can effectively resist the erosion of environmental factors such as humidity, temperature changes and chemical corrosion, thus ensuring the long-term stable operation of motor and electrical equipment.
[0003] However, there is a significant limitation in the application of traditional insulating varnish, that is, its curing process usually requires high temperature conditions. This requirement poses a great challenge in some occasions, especially for large motor and electrical equipment and insulating parts with complex structures that are not easy to be baked at high temperature. Due to the large size, complex structure of these equipment or parts, and the limitations of the on-site operation environment, it is often difficult to achieve ideal baking conditions, resulting in the insufficient curing of the insulating varnish, which in turn affects its insulation performance and film quality. In addition, the air-drying speed of traditional insulating varnish at room temperature is slow, and the performance of the coating after air-drying often cannot reach the level after high-temperature baking, which further limits its application in some occasions with high requirements for time efficiency and coating quality. Therefore, for large and medium-sized motor and electrical equipment, traditional insulating varnish cannot meet the requirements of air-drying at room temperature, nor can it guarantee excellent insulation performance and film coating processability. Summary of the Invention
[0004] The purpose of the present invention is to solve the technical problems of the limitations of traditional insulating varnish in coating large motor and electrical equipment and insulating parts that are not easy to be baked in the prior art, and to provide an air-drying type composite vegetable oil acid modified heat-resistant polyester resin and a preparation method thereof.
[0005] In order to achieve the above purpose, the present invention adopts the following technical solutions: In the first aspect, the present invention provides a preparation method of an air-drying type composite vegetable oil acid modified heat-resistant polyester resin, including: Mix and stir isocyanurate type saturated polyester resin, composite vegetable oil acid and phthalic anhydride until the acid value of the mixture is 38 - 48 mgKOH / g to obtain a primary mixture; Add E-20 epoxy resin to the primary mixture and keep it warm until the acid value drops below 15 mgKOH / g to obtain a secondary mixture. Add xylene, butanol and melamine resin to the secondary mixture, stir, filter and cool it in sequence to obtain an air-drying composite vegetable oil fatty acid modified heat-resistant polyester resin.
[0006] A further improvement lies in: The preparation method of the isocyanurate type saturated polyester resin is as follows: Heat trihydroxyethyl isocyanurate, isophthalic acid, catalyst and xylene to 180°C - 190°C and keep it warm for more than 2 h until it becomes transparent to obtain the isocyanurate type saturated polyester resin.
[0007] The mass ratio of the trihydroxyethyl isocyanurate to the isophthalic acid is 3 - 8:1 - 2.
[0008] The catalyst includes an organometallic catalyst, an organic amine catalyst or a potassium catalyst.
[0009] The specific operation of mixing and stirring the isocyanurate type saturated polyester resin, composite vegetable oil fatty acid and phthalic anhydride is as follows: Keep the isocyanurate type saturated polyester resin, composite vegetable oil fatty acid and phthalic anhydride at a temperature of 190°C - 210°C and stir for more than 2 h.
[0010] The temperature for keeping warm when adding E-20 epoxy resin to the primary mixture is 190°C - 210°C.
[0011] The specific operation of adding xylene solvent, butanol solvent and melamine resin to the secondary mixture is as follows: Under the condition of 100°C - 120°C, add xylene solvent and butanol solvent to the secondary mixture. When the temperature drops to 50°C - 80°C, add melamine resin and stir for more than 0.5 h.
[0012] The composite vegetable oil fatty acid includes linseed oil fatty acid and tung oil fatty acid.
[0013] The component weight ratio in the air-drying composite vegetable oil fatty acid modified heat-resistant polyester resin is as follows: Self-made isocyanurate type saturated polyester resin 15% - 25%, linseed oil fatty acid 10% - 25%, tung oil fatty acid 2% - 10%, phthalic acid 3% - 15%, E-20 epoxy resin 3% - 15%, melamine resin 5% - 10%, xylene 40% - 45%, butanol 5% - 10%.
[0014] In a second aspect, the present invention provides a air-drying type composite vegetable oil fatty acid modified heat-resistant polyester resin, which is characterized by being prepared by using the preparation method of the above-mentioned air-drying type composite vegetable oil fatty acid modified heat-resistant polyester resin.
[0015] Compared with the prior art, the present invention has the following beneficial effects: The present invention discloses a preparation method of an air-drying type composite vegetable oil fatty acid modified heat-resistant polyester resin. This method modifies isocyanurate type saturated polyester resin by introducing composite vegetable oil fatty acid, effectively solving the baking problems and defects such as brittle paint film existing in the application process of traditional insulating polyester resin varnish. This innovative modification strategy not only enhances the flexibility of the paint film, but also endows the resin with the function of air-drying at room temperature, thus greatly expanding its application range in the surface coating of insulating parts of F-class large and medium-sized motor and electrical equipment. In particular, the present invention uses tung oil fatty acid as the main component of the composite vegetable oil fatty acid, significantly improving the drying property of the heat-resistant polyester resin, enabling the resin to dry rapidly at room temperature, avoiding the cumbersome steps of high-temperature baking of traditional resins, reducing energy consumption and improving production efficiency. The modified heat-resistant polyester resin in the present invention has the ability to dry rapidly at room temperature, and at the same time, the cured coating has good electrical insulation performance, heat resistance and mechanical strength, which can meet the strict requirements of large and medium-sized motor and electrical equipment for insulating parts. In addition, the preparation process is simple, reducing production costs, improving production efficiency, effectively saving application costs, and promoting the sustainable development of the motor and electrical industry.
[0016] Furthermore, the adoption of self-made isocyanurate type saturated polyester resin makes the polymerization process easy to control, and can accurately regulate the molecular weight and molecular weight distribution of the prepolymer, providing a solid foundation for the synthesis of subsequent modified polyester resins. This characteristic not only facilitates the control of the reaction progress, but also has a positive impact on the key properties such as heat resistance and insulation of the final product, ensuring the stability and reliability of the product. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present invention, and therefore should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.
[0018] Figure 1 is a flowchart of a preparation method of an air-drying type composite vegetable oil fatty acid modified heat-resistant polyester resin in the present invention; Figure 2 is a step schematic diagram of a preparation method of an air-drying type composite vegetable oil fatty acid modified heat-resistant polyester resin in the present invention. Detailed implementation manners
[0019] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some but not all of the embodiments of the present invention. Components of the embodiments of the present invention generally described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.
[0020] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.
[0021] It should be noted that: like reference numerals and letters denote like items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.
[0022] The present invention will be further described in detail below with reference to the accompanying drawings: See Figure 1 , an embodiment of the present invention discloses a preparation method of an air-drying type composite vegetable oil acid modified heat-resistant polyester resin, including: S1. Mix and stir an isocyanurate type saturated polyester resin, a composite vegetable oil acid and phthalic anhydride until the acid value of the mixture is 38 - 48 mgKOH / g to obtain a primary mixture; S2. Add E-20 epoxy resin to the primary mixture and keep it warm until the acid value drops below 15 mgKOH / g to obtain a secondary mixture; S3. Add xylene, butanol and melamine resin to the secondary mixture, and obtain an air-drying type composite vegetable oil acid modified heat-resistant polyester resin after stirring, filtering and cooling in sequence.
[0023] The present invention discloses a preparation method of an air-drying composite vegetable oil acid-modified heat-resistant polyester resin. This method modifies isocyanurate-type saturated polyester resin by introducing composite vegetable oil acid, effectively solving the baking problems and defects such as brittle paint film existing in the application process of traditional insulating polyester resin varnish. This innovative modification strategy not only enhances the flexibility of the paint film but also endows the resin with the function of air-drying at room temperature, thus greatly broadening its application scope in the surface coating of insulating components of F-class large and medium-sized motor and electrical equipment. In particular, the present invention uses tung oil fatty acid as the main component of the composite vegetable oil acid, significantly improving the drying property of the heat-resistant polyester resin, enabling the resin to dry rapidly at room temperature, avoiding the cumbersome steps of high-temperature baking of traditional resins, reducing energy consumption and improving production efficiency. The modified heat-resistant polyester resin in the present invention has the ability to dry rapidly at room temperature, and at the same time, the cured coating has good electrical insulation performance, heat resistance and mechanical strength, which can meet the strict requirements of large and medium-sized motor and electrical equipment for insulating components. In addition, the preparation process is simple, reducing production costs, improving production efficiency, effectively saving application costs, and promoting the sustainable development of the motor and electrical industry.
[0024] See Figure 2 , the embodiment of the present invention discloses a preparation method of an air-drying composite vegetable oil acid-modified heat-resistant polyester resin, which is specifically illustrated by the following embodiments: Example 1 Step 1, self-prepare isocyanurate-type saturated polyester resin: Heat trihydroxyethyl isocyanurate, isophthalic acid, catalyst and xylene to 180 °C and keep warm for more than 2 h until it becomes transparent to obtain isocyanurate-type saturated polyester resin. The mass ratio of trihydroxyethyl isocyanurate to isophthalic acid is 3:1. The catalyst includes organometallic catalyst, organic amine catalyst or potassium catalyst.
[0025] Step 2, keep the isocyanurate-type saturated polyester resin, composite vegetable oil acid and phthalic anhydride at 190 °C and stir for more than 2 h until the acid value of the mixture is 38 mgKOH / g to obtain a primary mixture; the composite vegetable oil acid includes linseed oil fatty acid and tung oil fatty acid.
[0026] Step 3, add E-20 epoxy resin to the primary mixture and keep warm until the acid value drops below 15 mgKOH / g to obtain a secondary mixture; the heat preservation temperature is 190 °C.
[0027] Step 4, under the condition of 100 °C, add xylene solvent and butanol solvent to the secondary mixture, and when the temperature drops to 50 °C, add melamine resin and stir for more than 0.5 h.
[0028] The component weight ratios in the air-drying composite vegetable oil fatty acid-modified heat-resistant polyester resin are as follows: self-made isocyanurate-type saturated polyester resin 16%, linseed oil fatty acid 12%, tung oil fatty acid 2%, phthalic acid 7%, E-20 epoxy resin 6%, melamine resin 7%, xylene 42%, butanol 8%.
[0029] Example 2 Step 1, self-made isocyanurate-type saturated polyester resin: Heat triethylol isocyanurate, isophthalic acid, catalyst and xylene to 190 °C and keep warm for more than 2 h until it becomes transparent to obtain the isocyanurate-type saturated polyester resin. The mass ratio of triethylol isocyanurate to isophthalic acid is 8:2. The catalyst includes organometallic catalyst, organic amine catalyst or potassium catalyst.
[0030] Step 2, keep the isocyanurate-type saturated polyester resin, composite vegetable oil fatty acid and phthalic anhydride at 210 °C and stir while keeping warm for more than 2 h until the acid value of the mixture is 48 mgKOH / g to obtain a primary mixture; the composite vegetable oil fatty acid includes linseed oil fatty acid and tung oil fatty acid.
[0031] Step 3, add E-20 epoxy resin to the primary mixture and keep warm until the acid value drops below 15 mgKOH / g to obtain a secondary mixture; the heat preservation temperature is 210 °C.
[0032] Step 4, under the condition of 120 °C, add xylene solvent and butanol solvent to the secondary mixture. When the temperature drops to 80 °C, add melamine resin and stir for more than 0.5 h.
[0033] The component weight ratios in the air-drying composite vegetable oil fatty acid-modified heat-resistant polyester resin are as follows: self-made isocyanurate-type saturated polyester resin 18%, linseed oil fatty acid 10%, tung oil fatty acid 2%, phthalic acid 4%, E-20 epoxy resin 9%, melamine resin 8%, xylene 44%, butanol 6%.
[0034] Example 3 Step 1, self-made isocyanurate-type saturated polyester resin: Heat triethylol isocyanurate, isophthalic acid, catalyst and xylene to 183 °C and keep warm for more than 2 h until it becomes transparent to obtain the isocyanurate-type saturated polyester resin. The mass ratio of triethylol isocyanurate to isophthalic acid is 4:1. The catalyst includes organometallic catalyst, organic amine catalyst or potassium catalyst.
[0035] Step 2: Keep the isocyanurate - type saturated polyester resin, composite vegetable fatty acid, and phthalic anhydride at 195 °C with stirring for more than 2 h until the acid value of the mixture reaches 40 mgKOH / g to obtain a primary mixture; the composite vegetable fatty acid includes linseed oil fatty acid and tung oil fatty acid.
[0036] Step 3: Add E - 20 epoxy resin to the primary mixture and keep it warm until the acid value drops below 15 mgKOH / g to obtain a secondary mixture; the insulation temperature is 195 °C.
[0037] Step 4: Under the condition of 105 °C, add xylene solvent and butanol solvent to the secondary mixture. When the temperature drops to 60 °C, add melamine resin and stir for more than 0.5 h.
[0038] Self - made isocyanurate - type saturated polyester resin 20%, linseed oil fatty acid 12%, tung oil fatty acid 5%, phthalic acid 10%, E - 20 epoxy resin 3%, melamine resin 5%, xylene 40%, butanol 5%.
[0039] Example 4 Step 1: Self - made isocyanurate - type saturated polyester resin: Heat tri - hydroxyethyl isocyanurate, isophthalic acid, catalyst, and xylene to 188 °C and keep it warm for more than 2 h until it becomes transparent to obtain isocyanurate - type saturated polyester resin. The mass ratio of tri - hydroxyethyl isocyanurate to isophthalic acid is 8:2. The catalyst includes organometallic catalyst, organic amine - type catalyst, or potassium - type catalyst.
[0040] Step 2: Keep the isocyanurate - type saturated polyester resin, composite vegetable fatty acid, and phthalic anhydride at 205 °C with stirring for more than 2 h until the acid value of the mixture reaches 45 mgKOH / g to obtain a primary mixture; the composite vegetable fatty acid includes linseed oil fatty acid and tung oil fatty acid.
[0041] Step 3: Add E - 20 epoxy resin to the primary mixture and keep it warm until the acid value drops below 15 mgKOH / g to obtain a secondary mixture; the insulation temperature is 205 °C.
[0042] Step 4: Under the condition of 108 °C, add xylene solvent and butanol solvent to the secondary mixture. When the temperature drops to 70 °C, add melamine resin and stir for more than 0.5 h.
[0043] Self - made isocyanurate - type saturated polyester resin 15%, linseed oil fatty acid 11%, tung oil fatty acid 8%, phthalic acid 10%, E - 20 epoxy resin 3%, melamine resin 5%, xylene 40%, butanol 8%.
[0044] The modified heat-resistant polyester resins obtained in the above Examples 1-4 were baked and cured at 60°C / 0.5 h + 120°C / 3 h, and the specific results of performance tests are as follows:
[0045] The present invention also discloses an air-drying type composite vegetable oil acid modified heat-resistant polyester resin, which is prepared by the above method.
[0046] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.
Claims
1. A method for preparing an air-dried composite vegetable oil acid-modified heat-resistant polyester resin, characterized in that: include: The isocyanurate type saturated polyester resin, the composite vegetable oil acid and the phthalic anhydride are mixed and stirred until the acid value of the mixture is 38-48 mgKOH / g to obtain a primary mixture; Adding E-20 epoxy resin to the primary mixture and keeping the mixture warm until the acid value drops below 15 mgKOH / g to obtain a secondary mixture; Xylene, butanol and melamine resin are added to the secondary mixture, and the mixture is stirred, filtered and cooled in sequence to obtain an air-dried composite vegetable oil acid-modified heat-resistant polyester resin.
2. The method for preparing the air-dried composite vegetable oil acid-modified heat-resistant polyester resin according to claim 1, characterized in that: The preparation method of the isocyanurate type saturated polyester resin is: The temperature of trihydroxyethyl isocyanurate, isophthalic acid, a catalyst and xylene is raised to 180°C-190°C and kept at this temperature for more than 2 hours until the resin becomes transparent, thereby obtaining an isocyanurate type saturated polyester resin.
3. The method for preparing the air-dried composite vegetable oil acid-modified heat-resistant polyester resin according to claim 2, characterized in that: The mass ratio of trihydroxyethyl isocyanurate to isophthalic acid is 3-8:1-2.
4. The method for preparing the air-dried composite vegetable oil acid-modified heat-resistant polyester resin according to claim 2, characterized in that: The catalyst includes an organic metal catalyst, an organic amine catalyst or a potassium catalyst.
5. The method for preparing the air-dried composite vegetable oil acid-modified heat-resistant polyester resin according to claim 1, characterized in that: The mixing and stirring of the isocyanurate type saturated polyester resin, the composite vegetable oil acid and the phthalic anhydride is specifically as follows: Place isocyanurate type saturated polyester resin, composite vegetable oil acid and phthalic anhydride under stirring at 190°C-210°C for more than 2 hours.
6. The method for preparing the air-dried composite vegetable oil acid-modified heat-resistant polyester resin according to claim 1, characterized in that: E-20 epoxy resin is added to the primary mixture and the mixture is kept warm at a temperature of 190°C to 210°C.
7. The method for preparing the air-dried composite vegetable oil acid-modified heat-resistant polyester resin according to claim 1, characterized in that: The steps of adding xylene solvent, butanol solvent and melamine resin to the secondary mixture are as follows: At 100° C.-120° C., xylene solvent and butanol solvent are added to the secondary mixture, and when the temperature is lowered to 50° C.-80° C., melamine resin is added and stirred for more than 0.5 h.
8. The method for preparing the air-dried composite vegetable oil acid-modified heat-resistant polyester resin according to claim 1, characterized in that: The composite plant oil acid includes linseed oil fatty acid and tung oil fatty acid.
9. The method for preparing the air-dried composite vegetable oil acid-modified heat-resistant polyester resin according to claim 8, characterized in that: The weight ratio of the components in the air-dried composite vegetable oil acid-modified heat-resistant polyester resin is: Homemade isocyanurate type saturated polyester resin 15%-25%, linseed oil fatty acid 10%-25%, tung oil fatty acid 2%-10%, phthalic acid 3%-15%, E-20 epoxy resin 3%-15%, melamine resin 5%-10%, xylene 40%-45%, and butanol 5%-10%.
10. An air-dried composite vegetable oil acid-modified heat-resistant polyester resin, characterized in that: The resin is prepared by the method for preparing the air-dried composite vegetable oil acid-modified heat-resistant polyester resin according to any one of claims 1 to 9.