Heat-resistant solid unsaturated polyester resin-based electrical plastic and preparation method thereof

Abstract

The invention discloses heat-resistant solid unsaturated polyester resin-based electrical plastic, which is prepared from the following substances in parts by mass: 80 to 100 parts of unsaturated polyester resin, 1 to 2 parts of dispersing agents, 5 to 10 parts of aramid fibers, 30 to 50 parts of filling materials, 3 to 5 parts of antistatic agents and 2 to 3 parts of auxiliary agents. The preparation method comprises the following steps: adding the components in the heat-resistant solid unsaturated polyester resin-based electrical plastic into a high-speed stirrer, uniformly stirring, heating to 120-130 DEG C, carrying out plastic refining by adopting a parallel twin-screw extruder, feeding the extruded material into a single-screw granulator, granulating, cooling, and screening to obtain the heat-resistant solid unsaturated polyester resin-based electrical plastic. The prepared heat-resistant solid unsaturated polyester resin-based electrical plastic is high in electrical strength, good in flame retardant property, high in heat resistance and wide in application.

Description

Technical Field

[0001] The invention relates to the technical field of electrical plastics, and in particular to a heat-resistant solid unsaturated polyester resin-based electrical plastic and a preparation method thereof. Background Art

[0002] Unsaturated polyester-based electrical plastics are a type of electrical insulation material based on unsaturated polyester resins. Their performance is improved by adding various fillers, reinforcing materials, catalysts, promoters and other functional additives. They are widely used in insulation structural parts of electrical equipment, electrical housings, cable accessories, insulating rods, insulation parts of transformers and motors, and handles of various electrical tools. Its main features include: 1. Good mechanical properties: Unsaturated polyester-based plastics can significantly improve their mechanical strength and toughness through reinforcement modification, meeting the requirements of electrical equipment for strength and durability.

[0003] 2. Excellent electrical insulation properties: The cured unsaturated polyester has high volume resistivity and breakdown voltage, which can effectively prevent current leakage and ensure the safe operation of electrical equipment.

[0004] 3. Good processing performance: It can be formed by various processing methods such as molding, injection molding, hand lay-up, etc., which is convenient for manufacturing insulating parts with complex shapes.

[0005] 4. Chemical corrosion resistance: It has good resistance to a variety of chemicals and is suitable for use in harsh environments.

[0006] 5. Designability: The formula can be adjusted flexibly, and the curing speed, hardness, heat resistance and other properties of the resin can be adjusted according to different application requirements.

[0007] 6. Cost-effectiveness: Compared with some high-performance engineering plastics, unsaturated polyester-based plastics have lower costs and higher cost-effectiveness.

[0008] CN 108752890 B discloses an epoxy-modified unsaturated polyester resin electrical molding material, the components of which are as follows by mass percentage: 20%-50% epoxy-modified unsaturated polyester resin, 11%-60% filler, 0.003%-0.01% polymerization inhibitor, 0%-1% masterbatch, 25%-60% flame retardant, 1%-5% internal mold release agent, 0.1%-0.6% initiator, 0.4%-1% dispersant, and 7%-35% reinforcing fiber. For the epoxy-modified unsaturated polyester resin of the present invention, the benzene ring structure in the bisphenol A epoxy resin molecule is introduced to modify the unsaturated polyester resin, thereby achieving the purpose of high temperature resistance of the epoxy-modified unsaturated polyester resin electrical molding material; therefore, the prepared epoxy-modified unsaturated polyester resin electrical molding material has the advantages of good high temperature resistance and a wider range of applications. However, the raw materials used are highly toxic and limited in application. Summary of the invention

[0009] In view of the deficiencies of the prior art, the present invention provides a heat-resistant solid unsaturated polyester resin-based electrical plastic, comprising the following substances in mass fractions: Unsaturated polyester resin 80~100 parts Dispersant 1~2 parts Aramid fiber 5~10 parts Filler 30~50 parts 3~5 parts of antistatic agent 2~3 parts of additives.

[0010] Furthermore, the preparation method of the unsaturated polyester resin comprises the following steps: S1: Add 4-methyltetrahydrophthalic anhydride, phthalic anhydride, maleic anhydride, isophthalic acid, 3-fluoro-1,2-propylene glycol, trioctyl phosphate and antimony acetate into the reactor, start stirring, first heat to 120-130°C, react for 0.5h, then heat to 250-300°C, react for 2h; S2: First, a small amount of inert gas is introduced into the mixture obtained in step S1, and the temperature is lowered to 120-140°C, benzoic acid and fumaric anhydride are added, the inert gas is continued to be introduced, and the temperature is raised to 230-250°C again, and the reaction is carried out for 2h. First, a small amount of inert gas is introduced to partially remove low molecular components such as water, which is beneficial to subsequent reactions; S3: Stop introducing the inert gas, cool the mixed solution obtained in step S2 to 70-90°C, add p-benzoquinone, and heat to 140-160°C for 2h; S4: After cooling the mixed solution obtained in step S3, methyl ethyl ketone peroxide is added, and the mixture is reacted at a temperature between 40 and 60° C. for 1 hour, and then the mixture is heated to 90 to 95° C. and cured for 8 hours to obtain a heat-resistant solid unsaturated polyester resin.

[0011] Furthermore, the unsaturated polyester resin includes the following substances in mass fractions: 3-10 parts of 4-methyltetrahydrophthalic anhydride Phthalic anhydride 45~55 parts Maleic anhydride 5-10 parts Isophthalic acid 25~30 parts 3-Fluoro-1,2-propylene glycol 55~65 parts 2~5 parts of trioctyl phosphate Antimony acetate 4~6 parts 2~5 parts of benzoic acid Fumaric anhydride 23-26 parts 1~2 parts of benzoquinone 2~4 parts of methyl ethyl ketone peroxide.

[0012] The synthetic raw material is 3-fluoro-1,2-propylene glycol, and the introduction of fluorine atoms improves the corrosion resistance, thermal stability, high temperature resistance, and insulation performance of the prepared product. A certain amount of 4-methyltetrahydrophthalic anhydride is added to improve the compatibility with other components, and the prepared product has better uniformity and more stable performance.

[0013] Furthermore, the dispersant is at least one of calcium stearate and white carbon black.

[0014] Furthermore, the aramid fiber is a mixture of aramid 1313 and aramid 1414 in a ratio of 1:1 by mass. The introduction of the aramid fiber and the synergistic and complementary advantages of the two aramid fibers further enhance the heat resistance and stability of the prepared product.

[0015] Furthermore, the filler is a mixture of calcium carbonate, aluminum hydroxide and ethylene propylene rubber, the mass ratio of calcium carbonate, aluminum hydroxide and ethylene propylene rubber is 3:2:1, and the introduction of ethylene propylene rubber into the filler increases the toughness and impact strength of the prepared product, and has a wider application.

[0016] Furthermore, the antistatic agent is dodecyl dimethyl betaine or calcium dihydrogen phosphate. The introduction of the antistatic agent enables the product to be applied to a variety of specific scenarios.

[0017] Furthermore, the auxiliary agents are zinc borate and nano-alumina, and the mass ratio thereof is 1:1. The addition of zinc borate as a flame retardant and high temperature resistant auxiliary agent can decompose the generated zinc oxide and boric acid and other substances to form a protective film, thereby improving product performance; nano-alumina as an auxiliary agent can be evenly dispersed in the polymer material to form a network structure with strong thermal stability, thereby improving heat resistance.

[0018] Furthermore, the preparation method of the heat-resistant solid unsaturated polyester resin-based electrical plastic comprises the following steps: adding the components of the heat-resistant solid unsaturated polyester resin-based electrical plastic into a high-speed mixer, stirring evenly, then heating to 120-130°C, then using a parallel twin-screw extruder to refine the plastic, and sending the extruded material into a single-screw granulator for granulation, and then cooling and screening to obtain the heat-resistant solid unsaturated polyester resin-based electrical plastic.

[0019] The preparation method of the invention is simple, the process parameters are safe and controllable, the prepared heat-resistant solid unsaturated polyester resin-based electrical and electronic products have high electrical strength, good flame retardancy, high heat resistance and wide application. DETAILED DESCRIPTION

[0020] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present invention. It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0021] Example 1 A heat-resistant solid unsaturated polyester resin-based electrical plastic, comprising the following substances in mass fractions: Unsaturated polyester resin 80kg Calcium stearate 2kg Aramid 1313 3kg, Aramid 1414 3kg Calcium carbonate 15kg, aluminum hydroxide 10kg, EPDM 5kg Calcium dihydrogen phosphate 3kg 1.5kg zinc borate, 1.5kg nano alumina.

[0022] The preparation method of the above-mentioned heat-resistant solid unsaturated polyester resin-based electrical plastic is as follows: add the components of the heat-resistant solid unsaturated polyester resin-based electrical plastic into a high-speed mixer, stir evenly, then heat to 120-130°C, and then use a parallel twin-screw extruder to refine the plastic, and send the extruded material into a single-screw granulator for granulation, and then cool and screen to obtain the heat-resistant solid unsaturated polyester resin-based electrical plastic.

[0023] The preparation method of the above-mentioned unsaturated polyester resin is: S1: Add 5kg 4-methyltetrahydrophthalic anhydride, 50kg phthalic anhydride, 6kg maleic anhydride, 26kg isophthalic acid, 60kg 3-fluoro-1,2-propylene glycol, 3kg trioctyl phosphate and 5kg antimony acetate into the reactor, start stirring, first heat to 120-130°C, react for 0.5h, then heat to 250-300°C, react for 2h; S2: First, a small amount of inert gas is introduced into the mixture obtained in step S1, and the temperature is lowered to 120-140°C, 3 kg of benzoic acid and 22 kg of fumaric anhydride are added, the inert gas is continued to be introduced, and the temperature is raised to 230-250°C again, and the reaction is carried out for 2 hours; S3: Stop introducing the inert gas, cool the mixed solution obtained in step S2 to 70-90°C, add 2 kg of p-benzodiquinone, and heat to 140-160°C for 2 hours; S4: After cooling the mixed solution obtained in step S3, 3 kg of methyl ethyl ketone peroxide is added, and the mixture is reacted at a temperature between 40 and 60°C for 1 hour, and then the mixture is heated to 90 to 95°C and cured for 8 hours to obtain a heat-resistant solid unsaturated polyester resin, 80 kg of which is used to prepare a heat-resistant solid unsaturated polyester resin-based electrical plastic.

[0024] Example 2 A heat-resistant solid unsaturated polyester resin-based electrical plastic, comprising the following substances in mass fractions: Unsaturated polyester resin 80kg White carbon black 2kg Aramid 1313 3kg, Aramid 1414 3kg Calcium carbonate 15kg, aluminum hydroxide 10kg, EPDM 5kg Dodecyl dimethyl beet 3kg 1.5kg zinc borate, 1.5kg nano alumina.

[0025] The preparation method of the above-mentioned heat-resistant solid unsaturated polyester resin-based electrical plastic is as follows: add the components of the heat-resistant solid unsaturated polyester resin-based electrical plastic into a high-speed mixer, stir evenly, then heat to 120-130°C, and then use a parallel twin-screw extruder to refine the plastic, and send the extruded material into a single-screw granulator for granulation, and then cool and screen to obtain the heat-resistant solid unsaturated polyester resin-based electrical plastic.

[0026] The preparation method of the above-mentioned unsaturated polyester resin is: S1: Add 5kg 4-methyltetrahydrophthalic anhydride, 50kg phthalic anhydride, 6kg maleic anhydride, 26kg isophthalic acid, 60kg 3-fluoro-1,2-propylene glycol, 3kg trioctyl phosphate and 5kg antimony acetate into the reactor, start stirring, first heat to 120-130°C, react for 0.5h, then heat to 250-300°C, react for 2h; S2: First, a small amount of inert gas is introduced into the mixture obtained in step S1, and the temperature is lowered to 120-140°C, 3 kg of benzoic acid and 22 kg of fumaric anhydride are added, the inert gas is continued to be introduced, and the temperature is raised to 230-250°C again, and the reaction is carried out for 2 hours; S3: Stop introducing the inert gas, cool the mixed solution obtained in step S2 to 70-90°C, add 2 kg of p-benzodiquinone, and heat to 140-160°C for 2 hours; S4: After cooling the mixed solution obtained in step S3, 3 kg of methyl ethyl ketone peroxide is added, and the mixture is reacted at a temperature between 40 and 60°C for 1 hour, and then the mixture is heated to 90 to 95°C and cured for 8 hours to obtain a heat-resistant solid unsaturated polyester resin, 80 kg of which is used to prepare a heat-resistant solid unsaturated polyester resin-based electrical plastic.

[0027] Example 3 A heat-resistant solid unsaturated polyester resin-based electrical plastic, comprising the following substances in mass fractions: Unsaturated polyester resin 80kg Calcium stearate 2kg Aramid 1313 3kg, Aramid 1414 3kg Calcium carbonate 15kg, aluminum hydroxide 10kg, EPDM 5kg Dodecyl dimethyl beet 3kg 1.5kg zinc borate, 1.5kg nano alumina.

[0028] The preparation method of the above-mentioned heat-resistant solid unsaturated polyester resin-based electrical plastic is as follows: add the components of the heat-resistant solid unsaturated polyester resin-based electrical plastic into a high-speed mixer, stir evenly, then heat to 120-130°C, and then use a parallel twin-screw extruder to refine the plastic, and send the extruded material into a single-screw granulator for granulation, and then cool and screen to obtain the heat-resistant solid unsaturated polyester resin-based electrical plastic.

[0029] The preparation method of the above-mentioned unsaturated polyester resin is: S1: Add 6kg 4-methyltetrahydrophthalic anhydride, 52kg phthalic anhydride, 6kg maleic anhydride, 26kg isophthalic acid, 62kg 3-fluoro-1,2-propylene glycol, 3kg trioctyl phosphate and 5kg antimony acetate into the reactor, start stirring, first heat to 120-130°C, react for 0.5h, then heat to 250-300°C, react for 2h; S2: First, a small amount of inert gas is introduced into the mixture obtained in step S1, and the temperature is lowered to 120-140°C, 3 kg of benzoic acid and 22 kg of fumaric anhydride are added, the inert gas is continued to be introduced, and the temperature is raised to 230-250°C again, and the reaction is carried out for 2 hours; S3: Stop introducing the inert gas, cool the mixed solution obtained in step S2 to 70-90°C, add 2 kg of p-benzodiquinone, and heat to 140-160°C for 2 hours; S4: After cooling the mixed solution obtained in step S3, 3 kg of methyl ethyl ketone peroxide is added, and the mixture is reacted at a temperature between 40 and 60°C for 1 hour, and then the mixture is heated to 90 to 95°C and cured for 8 hours to obtain a heat-resistant solid unsaturated polyester resin, 80 kg of which is used to prepare a heat-resistant solid unsaturated polyester resin-based electrical plastic.

[0030] Comparative Example 1 The 3-fluoro-1,2-propanediol in Example 1 was replaced by 1,2-propanediol. The rest was the same as Example 1 and will not be described again.

[0031] Comparative Example 2 The auxiliary agent in Example 1 is removed, and the rest is the same as Example 1, which will not be described in detail.

[0032] The performance of the heat-resistant solid unsaturated polyester resin-based electrical plastics prepared in the above examples and comparative examples was tested. The test results are shown in Table 1.

[0033] From the data in the above table, it can be seen that the electrical strength, flammability and heat distortion temperature performance of the products prepared in Examples 1 to 3 are all good. The data of Comparative Example 1 shows that the introduction of fluorine atoms is beneficial to improving the performance of the final product; the data of Comparative Example 2 shows that the additive can improve the electrical strength and heat distortion temperature of the product.

Claims

1. A heat-resistant solid unsaturated polyester resin-based electrical plastic, characterized in that: Includes the following mass fractions of substances, Unsaturated polyester resin 80~100 parts Dispersant 1~2 parts Aramid fiber 5~10 parts Filler 30~50 parts 3~5 parts of antistatic agent 2~3 parts of additives.

2. The heat-resistant solid unsaturated polyester resin-based electrical plastic according to claim 1, characterized in that: The preparation method of the unsaturated polyester resin comprises the following steps: S1: Add 4-methyltetrahydrophthalic anhydride, phthalic anhydride, maleic anhydride, isophthalic acid, 3-fluoro-1,2-propylene glycol, trioctyl phosphate and antimony acetate into the reactor, start stirring, first heat to 120-130°C, react for 0.5h, then heat to 250-300°C, react for 2h; S2: First, a small amount of inert gas is introduced into the mixture obtained in step S1, and the temperature is lowered to 120-140° C., benzoic acid and fumaric anhydride are added, the inert gas is continued to be introduced, and the temperature is raised to 230-250° C. again, and the reaction is carried out for 2 hours; S3: Stop introducing the inert gas, cool the mixed solution obtained in step S2 to 70-90°C, add p-benzoquinone, and heat to 140-160°C for 2h; S4: After cooling the mixed solution obtained in step S3, methyl ethyl ketone peroxide is added, and the mixture is reacted at a temperature between 40 and 60° C. for 1 hour, and then the mixture is heated to 90 to 95° C. and cured for 8 hours to obtain a heat-resistant solid unsaturated polyester resin.

3. The heat-resistant solid unsaturated polyester resin-based electrical plastic according to claim 2, characterized in that: The unsaturated polyester resin includes the following substances by mass fraction: 3-10 parts of 4-methyltetrahydrophthalic anhydride Phthalic anhydride 45~55 parts Maleic anhydride 5-10 parts Isophthalic acid 25~30 parts 3-Fluoro-1,2-propylene glycol 55~65 parts 2~5 parts of trioctyl phosphate Antimony acetate 4~6 parts 2~5 parts of benzoic acid Fumaric anhydride 23-26 parts 1~2 parts of benzoquinone 2~4 parts of methyl ethyl ketone peroxide.

4. The heat-resistant solid unsaturated polyester resin-based electrical plastic according to claim 1, characterized in that: The dispersant is at least one of calcium stearate and white carbon black.

5. The heat-resistant solid unsaturated polyester resin-based electrical plastic according to claim 1, characterized in that: The aramid fiber is a mixture of aramid 1313 and aramid 1414 in a ratio of 1:1 by mass.

6. The heat-resistant solid unsaturated polyester resin-based electrical plastic according to claim 1, characterized in that: The filler is a mixture of calcium carbonate, aluminum hydroxide and ethylene-propylene rubber, and the mass ratio of calcium carbonate, aluminum hydroxide and ethylene-propylene rubber is 3:2:

1.

7. The heat-resistant solid unsaturated polyester resin-based electrical plastic according to claim 1, characterized in that: The antistatic agent is dodecyl dimethyl betaine or calcium dihydrogen phosphate.

8. The heat-resistant solid unsaturated polyester resin-based electrical plastic according to claim 1, characterized in that: The auxiliary agent is zinc borate and nano-aluminum oxide, and the mass ratio thereof is 1:

1.

9. The method for preparing the heat-resistant solid unsaturated polyester resin-based electrical plastic according to claim 1, characterized in that: The method comprises the following steps: adding various components of the heat-resistant solid unsaturated polyester resin-based electrical plastic into a high-speed mixer, stirring evenly, then heating to 120-130° C., then using a parallel twin-screw extruder to refine the plastic, sending the extruded material into a single-screw granulator for granulation, and then cooling and screening to obtain the heat-resistant solid unsaturated polyester resin-based electrical plastic.

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