An insulating rod material based on modified epoxy material and preparation method thereof

Abstract

The present invention discloses an insulating rod material based on modified epoxy material and a preparation method thereof, belonging to the technical field of insulating rods. The insulating rod material comprises the following raw materials in parts by weight: 70-90 parts of bisphenol epoxy resin, 15-25 parts of polydicyclopentadiene, 10-20 parts of modified glass fiber, 1-3 parts of curing accelerator, 4-12 parts of antioxidant, and 2-4 parts of lubricant. The prepared insulating rod material uses bisphenol epoxy resin as a matrix to give the insulating rod material excellent insulation and corrosion resistance; the antioxidant can greatly enhance the antioxidant performance of the insulating rod material; the modified glass fiber can not only promote the curing of the epoxy resin, but also significantly enhance the flame retardancy, mechanical properties and a certain degree of heat resistance of the insulating rod material, and the performance is long-lasting and stable; therefore, the insulating rod material prepared by the present invention has good insulation and corrosion resistance, stable and efficient flame retardancy, mechanical properties, antioxidant and a certain degree of heat resistance, and is halogen-free and flame retardant, and is environmentally friendly.

Description

Technical Field

[0001] The present invention belongs to the technical field of insulating rods, and in particular relates to an insulating rod material based on a modified epoxy material and a preparation method thereof. Background Art

[0002] The insulating rod, also known as the switch rod or link rod, consists of two parts: the working head and the insulating rod body. It is an insulating tool mainly used for short-term operation of live equipment, such as connecting or disconnecting high-voltage disconnectors, drop fuses, installing and removing portable grounding wires, and for measurement and testing. The insulating rod is one of the most commonly used safety tools for power workers and is widely used in power work.

[0003] The special working environment of insulating rods requires them to have high performance. The performance of insulating rods is mainly determined by the rod material. Therefore, improving the performance of insulating rod materials is of great significance. Currently, solid composite insulating materials are widely used for insulating rods. Generally, glass fiber is added as a reinforcement in an epoxy resin matrix. This method makes the insulating rod material have high mechanical strength and good insulation properties. However, as an inorganic material, glass fiber has poor compatibility with the epoxy resin matrix and is unevenly dispersed in the epoxy resin matrix, making it difficult to fully utilize the glass fiber's performance. In addition, insulating rods are easily corroded by humid and hot environments under long-term operation, resulting in insulation degradation and loss of insulation performance, which in turn affects electrical work. Moreover, the low oxygen index of epoxy resin poses a high safety risk when engaged in electrical work, limiting its use. Therefore, it is urgent to solve the above problems to meet the higher demands of the field of insulating rod technology. Summary of the Invention

[0004] The purpose of the present invention is to overcome the defects of the prior art and provide an insulating rod material based on a modified epoxy material and a preparation method thereof.

[0005] The purpose of the present invention can be achieved through the following technical solutions:

[0006] A method for preparing an insulating rod material based on a modified epoxy material comprises the following steps:

[0007] Bisphenol epoxy resin, polydicyclopentadiene (PDCPD), modified glass fiber, curing accelerator, antioxidant and lubricant are mixed and added to a high-speed mixer. Mix for 45 minutes to fully mix the components. Then pour into a twin-screw extruder for melt blending and extrusion. After discharge, the material is cooled to room temperature to obtain an insulating rod material based on modified epoxy material.

[0008] Furthermore, the raw materials are calculated in parts by weight as follows: 70-90 parts of bisphenol epoxy resin, 15-25 parts of polydicyclopentadiene, 10-20 parts of modified glass fiber, 1-3 parts of curing accelerator, 4-12 parts of antioxidant, and 2-4 parts of lubricant.

[0009] Furthermore, the curing accelerator is one of triethylamine, triethanolamine and o-hydroxybenzyldimethylamine.

[0010] Furthermore, the lubricant is one of zinc stearate, magnesium stearate and epoxidized soybean oil.

[0011] Furthermore, the antioxidant is prepared by compounding antioxidant 1010 and antioxidant 168 in a mass ratio of 3:1.

[0012] The bisphenol epoxy resin is used as the matrix to give the insulating rod material excellent insulation and corrosion resistance; the added polydicyclopentadiene not only has good insulation, but also can improve the heat resistance and mechanical properties of the rod material; the curing accelerator is a tertiary amine accelerator, which can effectively promote the curing of epoxy resin; the added antioxidant is a compound of hindered phenol antioxidant and phosphite auxiliary antioxidant, the two can play a synergistic role and greatly enhance the antioxidant performance of the insulating rod material.

[0013] Furthermore, the modified glass fiber is prepared by the following steps:

[0014] S1. 2-aminobenzimidazole, piperidine (condensing agent) and toluene were mixed in a three-necked flask equipped with a stirring device, the temperature was raised to 50° C., and the mixture was stirred until the solid was completely dissolved. Glutaraldehyde was added and the reaction was kept warm for 6 h. After the reaction was completed, the mixture was naturally cooled, filtered, and the solvent was removed by distillation under reduced pressure. The mixture was washed with anhydrous ethanol 2-3 times and dried in vacuo to obtain intermediate 1; the ratio of the amount of 2-aminobenzimidazole, piperidine, toluene and glutaraldehyde was 13.3 g:15 mL:100 mL:11.8 g;

[0015] Under the action of a condensing agent, the amino group on 2-aminobenzimidazole condenses with the aldehyde group on glutaraldehyde to form an imine group (C=N Schiff base structure). By controlling the molar ratio of the two to be close to 1:1 and a slight excess of glutaraldehyde, only one aldehyde group on glutaraldehyde participates in the reaction, yielding intermediate 1. The specific reaction process is shown below:

[0016]

[0017] S2. In a three-necked flask equipped with a stirring device, the intermediate 1, 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, piperidine and N,N-dimethylformamide (DMF) were mixed and stirred uniformly, the reaction temperature was controlled to 60° C., and the reaction was kept warm for 6 hours. After the reaction was completed, it was naturally cooled, filtered, and part of the solvent was removed by distillation under reduced pressure. The product was then purified by column chromatography (eluent: a mixed solvent of benzene / ethyl acetate in a volume ratio of 3:4), the eluent was removed by rotary evaporation, and vacuum dried to obtain intermediate 2; the ratio of the amount of intermediate 1, 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, piperidine, and N,N-dimethylformamide was 21.5 g:25.6 g:15 mL:150 mL;

[0018] Under the action of a condensing agent, the amino group on 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane condenses with the aldehyde group on intermediate 1 to form an imine group (C=N Schiff base structure). By controlling the molar ratio of the two to be close to 1:1 and a slight excess of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, only one amino group on 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane participates in the reaction to obtain intermediate 2. The specific reaction process is shown below:

[0019]

[0020] S3, the glass fiber was cleaned and dried in an acetone solution, and then placed in a hydrochloric acid solution for treatment for 8 hours and then dried. The treated glass fiber was placed in water, and a silane coupling agent KH-560 was added to react at room temperature for 6 hours, and then dried at 80°C for 4 hours. Then, the glass fiber was ultrasonically cleaned in an ethanol solution for 20 minutes, and finally vacuum-dried at 100°C for 2 hours to obtain a pre-modified glass fiber; the ratio of the amount of glass fiber, hydrochloric acid solution, water, and silane coupling agent KH-560 was 1g:100mL:100mL:4.5g;

[0021] The glass fiber is pre-modified by using silane coupling agent KH-560 so that epoxy groups are connected to its surface to obtain pre-modified glass fiber;

[0022] S4. Add N,N-dimethylformamide and pre-modified glass fiber to a flask, disperse them evenly by ultrasonication for 15 minutes, add intermediate 2, slowly heat to 95°C, turn on magnetic stirring (speed 1200r / min), stir for 6 hours, stop heating, let it stand, after the temperature in the reaction bottle drops to 30°C, filter, wash with anhydrous ethanol 3-4 times, and freeze-dry to obtain modified glass fiber; the ratio of N,N-dimethylformamide, pre-modified glass fiber, and intermediate 2 is 100mL:1g:8.5g;

[0023] The epoxy groups on the surface of the pre-modified glass fiber can undergo a ring-opening reaction with the amino groups on the intermediate 2 molecule to obtain modified glass fiber;

[0024] Glass fiber is a high-strength filling material. By modifying it, the modified glass fiber is grafted with organic molecular chains through chemical bonding, that is, an organic layer is formed on its surface, which can improve the surface hydrophobicity of the glass fiber, improve the compatibility of the glass fiber and the epoxy resin matrix, make the modified glass fiber disperse evenly in the matrix, reduce the occurrence of agglomeration, and give full play to the performance of the glass fiber, greatly enhancing the mechanical properties of the matrix; not only that, the modified glass fiber also contains -Si-O-Si- chain segments, benzimidazole and Schiff base structures, among which the -Si-O-Si- chain segments are good flame retardants and smoke suppression components, which can not only improve the flame retardancy of the matrix It can also have a certain smoke suppression effect; in addition, due to the high bond energy of the Si-O bond, it can improve the heat resistance of the matrix to a certain extent; the C=N double bond in the introduced Schiff base structure can generate a carbon-nitrogen six-membered ring at high temperature. This six-membered ring structure enables the matrix to form a stable cross-linked network, which synergizes with the -Si-O-Si- chain segment and greatly enhances the flame retardant properties of the matrix; finally, the pyridinic nitrogen in the benzimidazole structure can react with the epoxy group with high reactivity in the epoxy resin, and can synergize with the tertiary amine accelerator to promote the curing of the epoxy resin, so that the epoxy resin matrix forms a cross-linked three-dimensional network macromolecular polymer, thereby improving the various properties of the epoxy resin matrix;

[0025] It should be added that the modified glass fiber grafted with organic molecular chains can effectively prevent the migration and seepage of small organic molecules, ensuring the long-term performance of various properties.

[0026] Beneficial effects of the present invention:

[0027] 1. The insulating rod material prepared by the present invention uses bisphenol epoxy resin as a matrix to give the insulating rod material excellent insulation and corrosion resistance;

[0028] 2. The added antioxidant is a compound of hindered phenol antioxidant and phosphite auxiliary antioxidant. The two can play a synergistic role and greatly enhance the antioxidant performance of the insulating rod material;

[0029] 3. Compared with ordinary glass fibers, the modified glass fiber has better compatibility with the epoxy resin matrix. It can not only promote the curing of epoxy resin, but also significantly enhance the flame retardancy, mechanical properties and heat resistance of the insulating rod material to a certain extent, and the performance is long-lasting and stable.

[0030] Therefore, the insulating rod material prepared by the present invention has good insulation and corrosion resistance, stable and efficient flame retardancy, mechanical properties, antioxidant and a certain degree of heat resistance, and is halogen-free and flame retardant, environmentally friendly, and has important application value in the field of insulating rod technology. DETAILED DESCRIPTION

[0031] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0032] Example 1

[0033] Preparation of modified glass fiber:

[0034] S1. In a three-necked flask equipped with a stirring device, 13.3 g of 2-aminobenzimidazole, 15 mL of piperidine and 100 mL of toluene were mixed, the temperature was raised to 50° C., and the mixture was stirred until the solid was completely dissolved. 11.8 g of glutaraldehyde was added and the mixture was kept warm for 6 h. After the reaction was completed, the mixture was naturally cooled, filtered, and the solvent was removed by distillation under reduced pressure. The mixture was washed with anhydrous ethanol 2-3 times and dried in vacuo to obtain intermediate 1;

[0035] S2, in a three-necked flask equipped with a stirring device, 21.5g of intermediate 1, 25.6g of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, 15mL of piperidine and 150mL of N,N-dimethylformamide were mixed and stirred uniformly, the reaction temperature was controlled to 60°C, and the reaction was kept warm for 6h. After the reaction was completed, it was naturally cooled, filtered, and part of the solvent was removed by distillation under reduced pressure. Then, it was purified by column chromatography (the eluent was a mixed solvent of benzene / ethyl acetate, the volume ratio of the two was 3:4), the eluent was removed by rotary evaporation, and vacuum drying was performed to obtain intermediate 2;

[0036] S3. After cleaning and drying 1 g of glass fiber in an acetone solution, the fiber was placed in 100 mL of hydrochloric acid solution (mass fraction 12%) for 8 h and then dried. The treated glass fiber was placed in 100 mL of water, 4.5 g of silane coupling agent KH-560 was added, and the mixture was reacted at room temperature for 6 h. The reaction was then carried out at 80° C. for 4 h, followed by ultrasonic cleaning in an ethanol solution for 20 min, and finally vacuum drying at 100° C. for 2 h to obtain a pre-modified glass fiber.

[0037] S4. Add 100 mL of N,N-dimethylformamide and 1 g of pre-modified glass fiber into a flask, disperse evenly by ultrasonication for 15 minutes, add 8.5 g of intermediate 2, slowly heat to 95°C, start magnetic stirring (speed 1200 r / min), stir for 6 hours, stop heating, let it stand, wait until the temperature in the reaction bottle drops to 30°C, filter, wash with anhydrous ethanol 4 times, and freeze-dry to obtain modified glass fiber.

[0038] Example 2

[0039] Preparation of modified glass fiber:

[0040] S1, in a three-necked flask equipped with a stirring device, 26.6g of 2-aminobenzimidazole, 30mL of piperidine and 200mL of toluene were mixed, the temperature was raised to 50°C, and the mixture was stirred until the solid was completely dissolved. 23.6g of glutaraldehyde was added and the mixture was kept warm for 6h. After the reaction was completed, the mixture was naturally cooled, filtered, and the solvent was removed by distillation under reduced pressure. The mixture was washed twice with anhydrous ethanol and dried in vacuo to obtain intermediate 1;

[0041] S2, in a three-necked flask equipped with a stirring device, 43.0g of intermediate 1, 51.2g of 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, 30mL of piperidine and 300mL of N,N-dimethylformamide were mixed and stirred uniformly, the reaction temperature was controlled to 60°C, and the reaction was kept warm for 6h. After the reaction was completed, it was naturally cooled, filtered, and part of the solvent was removed by distillation under reduced pressure. It was then purified by column chromatography (eluent using a mixed solvent of benzene / ethyl acetate, the volume ratio of the two being 3:4), the eluent was removed by rotary evaporation, and vacuum drying was performed to obtain intermediate 2;

[0042] S3. 2 g of glass fiber was washed and dried in an acetone solution, then placed in 200 mL of hydrochloric acid solution (mass fraction 12%) for 8 h and dried. The treated glass fiber was placed in 200 mL of water, 9 g of silane coupling agent KH-560 was added, and the mixture was reacted at room temperature for 6 h. The mixture was then dried at 80° C. for 4 h, ultrasonically cleaned in an ethanol solution for 20 min, and finally vacuum dried at 100° C. for 2 h to obtain a pre-modified glass fiber.

[0043] S4. Add 200 mL of N,N-dimethylformamide and 2 g of pre-modified glass fiber into a flask, disperse evenly by ultrasonication for 15 min, add 17 g of intermediate 2, slowly heat to 95 ° C, start magnetic stirring (speed 1200 r / min), stir for 6 h, stop heating, let it stand, wait until the temperature in the reaction bottle drops to 30 ° C, filter, wash with anhydrous ethanol 4 times, and freeze-dry to obtain modified glass fiber.

[0044] Example 3

[0045] 70 g of bisphenol epoxy resin, 15 g of polydicyclopentadiene, 10 g of the modified glass fiber prepared in Example 1, 1 g of triethylamine, 4 g of antioxidant (prepared by compounding 3 g of antioxidant 1010 and 1 g of antioxidant 168) and 2 g of zinc stearate were mixed and added to a high-speed mixer. Mixed for 45 minutes to fully mix the components, the mixture was poured into a twin-screw extruder for melt blending and extrusion, and the material was cooled to room temperature after discharge to obtain an insulating rod material based on the modified epoxy material.

[0046] Example 4

[0047] 80 g of bisphenol epoxy resin, 20 g of polydicyclopentadiene, 15 g of the modified glass fiber prepared in Example 2, 2 g of triethanolamine, 8 g of antioxidant (prepared by compounding 6 g of antioxidant 1010 and 2 g of antioxidant 168) and 3 g of magnesium stearate were mixed and added to a high-speed mixer. Mixed for 45 minutes to fully mix the components, the mixture was poured into a twin-screw extruder for melt blending and extrusion, and the material was cooled to room temperature after discharge to obtain an insulating rod material based on the modified epoxy material.

[0048] Example 5

[0049] 90 g of bisphenol epoxy resin, 25 g of polydicyclopentadiene, 20 g of the modified glass fiber prepared in Example 1, 3 g of triethanolamine, 12 g of an antioxidant (prepared by compounding 9 g of antioxidant 1010 and 3 g of antioxidant 168) and 4 g of magnesium stearate were mixed and added to a high-speed mixer. Mixed for 45 minutes to fully mix the components, the mixture was poured into a twin-screw extruder for melt blending and extrusion, and the material was cooled to room temperature after discharge to obtain an insulating rod material based on a modified epoxy material.

[0050] Comparative Example 1

[0051] Ordinary glass fibers of the same quality were used to replace the modified glass fibers in Example 5, and the remaining steps were the same as those in Example 5 to obtain an insulating rod material.

[0052] Comparative Example 2

[0053] A commercially available flame retardant epoxy resin material was used.

[0054] The following performance tests were performed on Examples 3 to 5 and Comparative Examples 1 and 2 according to different test standards:

[0055] Adopt the national standard GB 13398-2003 "Hollow insulating tubes, foam-filled insulating tubes and solid insulating rods for live working" for tensile strength and normal resistivity;

[0056] The national standard GB / T 2406-2008 "Test method for combustion performance of plastics" is used to measure the limiting oxygen index of the sample before and after standing at room temperature for 180 days;

[0057] Thermal aging test: Place the sample in a 150°C environment and let it stand for 24 hours. Then test the tensile strength of the sample (GB13398-2003) and calculate the tensile strength retention rate; tensile strength retention rate = tensile strength after test / tensile strength before test × 100%;

[0058] The measurement results are shown in the following table:

[0059]

[0060] As can be seen from the above table, the flame retardancy, mechanical properties, and heat resistance of the insulating rod materials prepared in the embodiments of the present invention are higher than those in the comparative example, and the performance is long-lasting and stable. In addition, as the content of modified glass fiber in Examples 3 to 5 continues to increase, the various properties of the insulating rod materials are enhanced. Therefore, the present invention has important application value in the field of insulating rod technology.

[0061] Throughout the specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0062] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the described specific embodiments or replace them in similar ways. As long as they do not deviate from the invention or exceed the scope defined by the claims, they should all fall within the scope of protection of the present invention.

Claims

1. A method for preparing an insulating rod material based on a modified epoxy material, characterized in that: The following steps are involved: Bisphenol epoxy resin, polydicyclopentadiene, modified glass fiber, curing accelerator, antioxidant and lubricant are mixed, added into a high-speed mixer for mixing, poured into a twin-screw extruder for melt blending and extrusion, and cooled to room temperature after discharge to obtain an insulating rod material based on modified epoxy resin; Wherein, the modified glass fiber is prepared by the following steps: S1. Mix 2-aminobenzimidazole, piperidine, and toluene, heat to 50°C, add glutaraldehyde, and keep warm for 6 hours. After the reaction is complete, cool naturally, filter, evaporate under reduced pressure, wash, and dry in vacuo to obtain intermediate 1. S2, mixing intermediate 1, 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, piperidine and N,N-dimethylformamide, stirring uniformly, reacting at 60°C for 6 hours, and cooling naturally after completion of the reaction, filtering, distilling under reduced pressure, purifying by column chromatography, rotary evaporation, and vacuum drying to obtain intermediate 2; S3, washing and drying the glass fiber in an acetone solution, placing it in a hydrochloric acid solution for 8 hours and then drying it, placing the treated glass fiber in water, adding a silane coupling agent KH-560 and reacting it at room temperature for 6 hours, drying it at 80°C for 4 hours, and then ultrasonically washing it in an ethanol solution for 20 minutes, and vacuum drying it to obtain a pre-modified glass fiber; S4. Add N,N-dimethylformamide and pre-modified glass fiber into a flask, disperse them evenly by ultrasonication for 15 minutes, add intermediate 2, slowly heat up to 95°C, start magnetic stirring, stop heating after stirring for 6 hours, let it stand, filter, wash and dry to obtain modified glass fiber.

2. The method for preparing an insulating rod material based on a modified epoxy material according to claim 1, characterized in that: In step S1, the ratio of 2-aminobenzimidazole, piperidine, toluene, and glutaraldehyde is 13.3 g:15 mL:100 mL:11.8 g.

3. The method for preparing an insulating rod material based on a modified epoxy material according to claim 1, characterized in that: In step S2, the ratio of the amount of intermediate 1, 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane, piperidine, and N,N-dimethylformamide is 21.5 g:25.6 g:15 mL:150 mL.

4. The method for preparing an insulating rod material based on a modified epoxy material according to claim 1, characterized in that: In step S3, the ratio of glass fiber, hydrochloric acid solution, water, and silane coupling agent KH-560 is 1 g:100 mL:100 mL:4.5 g.

5. The method for preparing an insulating rod material based on a modified epoxy material according to claim 1, characterized in that: In step S4, the ratio of N,N-dimethylformamide, pre-modified glass fiber, and intermediate 2 is 100 mL: 1 g: 8.5 g.

6. The method for preparing an insulating rod material based on a modified epoxy material according to claim 1, characterized in that: The raw materials are calculated as follows in parts by weight: 70-90 parts of bisphenol epoxy resin, 15-25 parts of polydicyclopentadiene, 10-20 parts of modified glass fiber, 1-3 parts of curing accelerator, 4-12 parts of antioxidant, and 2-4 parts of lubricant.

7. The method for preparing an insulating rod material based on a modified epoxy material according to claim 1, characterized in that: The antioxidant is prepared by compounding antioxidant 1010 and antioxidant 168 in a mass ratio of 3:

1.

8. An insulating rod material based on modified epoxy material, characterized in that: Prepared according to the method according to any one of claims 1 to 7.

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