Weather-resistant synthetic material, preparation method thereof and external insulation product prepared from weather-resistant synthetic material

Abstract

According to the weather-resistant synthetic material and the preparation method thereof and the prepared external insulation product, on the basis of epoxy resin, a curing agent, an accelerant, a silane coupling agent, silicon dioxide and aluminum hydroxide filler, polyether organic matters with different molecular weights are reasonably matched, and through mutual matching of polyether with different molecular weights, the weather-resistant synthetic material is prepared. A compact three-dimensional curing cross-linked network with chain segment activity capability is constructed, so that the mechanical toughness and low water absorption rate of the weather-resistant epoxy insulating material are synergistically improved, and finally, the operation reliability of an insulating product is effectively improved.

Description

Technical Field

[0001] The invention relates to the technical field of composite insulation materials for power transmission lines, and in particular to a weather-resistant synthetic material and a preparation method thereof and an external insulation product obtained by the preparation. Background Art

[0002] Silicone rubber composite insulators are an important part of power transmission and transformation equipment, but problems such as sheath damage, "sheath-core rod" interface aging, and core rod decay during operation have brought serious troubles to the power industry. Although existing weather-resistant epoxy resin composite insulation products have certain weather resistance, insulation performance, and interface aging resistance, the strong brittleness and high water absorption of epoxy resin itself have greatly restricted its application in external insulation. Therefore, how to achieve the synergistic improvement of the mechanical toughness and low water absorption of weather-resistant epoxy insulation materials, thereby improving the reliability of the operation of insulation products, has become an urgent problem that needs to be solved. Summary of the invention

[0003] The present invention provides a synthetic material for weather-resistant hard insulators with good mechanical properties and a preparation method thereof. The present invention innovatively proposes to construct a dense three-dimensional cross-linked network with segment activity by synergistically matching organic molecules of different molecular weights, so as to achieve synergistic improvement of weather-resistant epoxy toughness and low water absorption.

[0004] In a first aspect, the present invention provides a weather-resistant synthetic material with good mechanical properties. The weather-resistant synthetic material comprises, by weight, 90 to 170 parts of epoxy resin, 60 to 170 parts of curing agent, 50 to 300 parts of aluminum hydroxide filler, 0.1 to 2 parts of accelerator, 2 to 6 parts of silane coupling agent and 50 to 300 parts of silicon dioxide; wherein, by weight, the epoxy resin comprises 50 to 98 parts of a first material and 2 to 50 parts of a second material, wherein the first material is diglycidyl hexahydrophthalate, 3,4-epoxycyclohexylcarboxylate, A combination of one or more of 3', 4'-epoxycyclohexyl methyl ester, bis((3,4-epoxycyclohexyl)methyl)adipate and cyclohexane-1,2-dicarboxylic acid diglycidyl ester; the second material is polyether polyols of different molecular weights and / or terminal epoxy polyethers of different molecular weights; and the weather-resistant synthetic material is constructed to obtain a dense three-dimensional cured cross-linked network with segment activity through compounding of the polyether molecules in the second material.

[0005] Optionally, the weather-resistant synthetic material includes, by weight: 90 to 120 parts of epoxy resin, 60 to 120 parts of curing agent, 50 to 300 parts of aluminum hydroxide filler, 0.5 to 1.5 parts of accelerator, 2 to 5 parts of silane coupling agent and 50 to 300 parts of silicon dioxide.

[0006] Optionally, the weather-resistant synthetic material includes, by weight: 100 parts of epoxy resin, 100 parts of curing agent, 280 parts of aluminum hydroxide filler, 1.5 parts of accelerator, 1 part of silane coupling agent and 80 parts of silicon dioxide.

[0007] Optionally, the first material accounts for 90-97 parts by weight of the epoxy resin, and the second material accounts for 3-10 parts by weight of the epoxy resin.

[0008] Optionally, the first material accounts for 95 parts by weight of the epoxy resin, and the second material accounts for 5 parts by weight of the epoxy resin.

[0009] Optionally, the second material includes a first molecular weight polyether, a second molecular weight polyether and a third molecular weight polyether, wherein the first molecular weight polyether is one or more of a polyether polyol with a molecular weight of 200-500 and a terminal epoxy polyether, the second molecular weight polyether is one or more of a polyether polyol with a molecular weight of 500-1000 and a terminal epoxy polyether, the third molecular weight polyether is one or more of a polyether polyol with a molecular weight of 1000-5000 and a terminal epoxy polyether, and the ratio of the first molecular weight polyether, the second molecular weight polyether and the third molecular weight polyether is 1:2:2.

[0010] Optionally, the curing agent is a combination of one or more of tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, succinic anhydride and amino-terminated polyether; The curing agent is methyl hexahydrophthalic anhydride; The silicon dioxide is micron silicon dioxide.

[0011] In a second aspect, the present invention provides a method for preparing any one of the weather-resistant synthetic materials described above, the method comprising: According to weight percentage, 90 to 170 parts of epoxy resin, 60 to 170 parts of curing agent, 0.1 to 2 parts of accelerator and 2 to 6 parts of silane coupling agent are sequentially placed in a container, and the solution in the container is fully stirred and mixed at a first stirring speed; Divide 50 to 300 parts of aluminum hydroxide filler into multiple parts, slowly pour them into the container in batches, and stir and mix them thoroughly at the second stirring speed; 50 to 300 parts of silica filler are placed in the container and are fully stirred and mixed at a third stirring speed. The polyether molecules of the second material are compounded to form a three-dimensional solidified cross-linked network with segment mobility and density, thereby finally obtaining the weather-resistant synthetic material.

[0012] In a third aspect, the present invention provides a novel weather-resistant composite external insulator, which is obtained by injection molding the weather-resistant synthetic material prepared as described above using an automatic pressure gel molding process (APG).

[0013] Optionally, the pressure of APG injection molding is 0.2-0.8 MPa, the temperature of the mold for the first curing molding is 100-160°C, and the holding time is 20-60 min; After the insulation time is over, the second curing molding is carried out, wherein the temperature of the mold for the second curing molding is 100-150° C., and the time of the second curing molding is 3-10 hours, and finally a new weather-resistant composite external insulator is prepared.

[0014] The beneficial effects of the present invention are as follows: The present invention proposes to rationally match polyether organic matter of different molecular weights with other ingredients on the basis of epoxy resin, curing agent, accelerator, silane coupling agent, silica and aluminum hydroxide filler, so as to construct a dense three-dimensional cured cross-linked network with segment activity through the mutual coordination of polyethers of different molecular weights, thereby achieving the synergistic improvement of the mechanical toughness and low water absorption rate of weather-resistant epoxy insulation materials, and ultimately improving the operational reliability of insulation products.

[0015] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings: Figure 1 It is a schematic flow chart of a method for preparing a weather-resistant synthetic material provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0017] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not limit the present invention.

[0018] Silicone rubber composite insulation products are an important part of power transmission and transformation equipment, but problems such as sheath damage, "sheath-core rod" interface aging, and core rod decay during operation have caused serious troubles to the power industry. Although epoxy resin composite insulation products have excellent interface aging resistance and mechanical properties, epoxy resin composite insulation materials themselves have poor weather resistance, so the lack of hydrophobicity restricts their application in external insulation.

[0019] In order to solve the above problems, the present invention improves the weather resistance and hydrophobicity of epoxy resin composite insulation products through a large number of experiments. Specifically, the embodiment of the present invention designs a weather-resistant synthetic material with good mechanical properties. According to the weight percentage, the weather-resistant synthetic material includes: 90-170 parts of epoxy resin, 60-170 parts of curing agent, 50-300 parts of aluminum hydroxide filler, 0.1-2 parts of accelerator, 2-6 parts of silane coupling agent and 50-300 parts of silicon dioxide; Among them, in terms of weight parts, the epoxy resin includes 50 to 98 parts of the first material and 2 to 50 parts of the second material, the first material is a combination of one or more of hexahydrophthalic acid diglycidyl ester, 3,4-epoxycyclohexylcarboxylic acid-3', 4'-epoxycyclohexyl methyl ester, bis((3,4-epoxycyclohexyl)methyl)adipate and cyclohexane-1,2-dicarboxylic acid diglycidyl ester, and the second material is polyether polyols of different molecular weights and / or terminal epoxy polyethers of different molecular weights. Through the compounding of the polyether molecules in the second material, the weather-resistant synthetic material is constructed to obtain a dense three-dimensional cured cross-linked network with segment activity.

[0020] In short, the embodiment of the present invention is to enable the weather-resistant synthetic material to construct a dense three-dimensional cured cross-linked network with segment activity through the polyether polyol and / or terminal epoxy polyether in the second material, so as to achieve a synergistic improvement in the mechanical toughness and low water absorption of the weather-resistant epoxy insulation material, thereby ultimately greatly improving the operating reliability of the insulation product.

[0021] That is to say, the epoxy resin in the embodiment of the present invention includes 90 to 98 parts of the first material and 2 to 10 parts of the second material, wherein the first material is a combination of one or more weather-resistant epoxy resins such as hexahydrophthalic acid diglycidyl ester, and the second material is a combination of one or more polyether organics such as polyether polyols of different molecular weights and or terminal epoxy polyethers of different molecular weights. The embodiment of the present invention realizes the compounding of polyether molecules by reasonably matching polyether organics of different molecular weights and coordinating with each other of different molecular weights, thereby constructing a three-dimensional cured cross-linked network with segment activity and density, thereby achieving a synergistic improvement in the mechanical toughness and low water absorption of weather-resistant epoxy insulation materials, and ultimately effectively improving the operational reliability of insulation products.

[0022] Specifically, in an embodiment of the present invention, the second material is a polyether polyol of different molecular weight, or a terminal epoxy polyether of different molecular weight, or a polyether polyol of different molecular weight and a terminal epoxy polyether of different molecular weight, to achieve polyether molecule compounding, so that the final weather-resistant synthetic material can construct a three-dimensional cured cross-linked network with segment activity and density.

[0023] In specific implementation, the embodiments of the present invention use low molecular weight polyether to increase the cross-linking density of the cross-linking network, resist the invasion of water molecules, and reduce the saturated water absorption rate, and use high molecular weight polyether to improve the activity and mechanical toughness of the low molecular weight polyether chain segment; therefore, the present invention achieves the synergy between high cross-linking density and high mechanical toughness through the reasonable combination of polyethers of different molecular weights, that is, polyether polyols and / or terminal epoxy polyethers of different molecular weights.

[0024] It should be noted that the contents of each component in the embodiments of the present invention are all measured by weight.

[0025] Among them, the epoxy resin in the embodiment of the present invention has good physical, mechanical and chemical properties, such as epoxy resin has good chemical corrosion resistance, moisture resistance, wear resistance, high temperature resistance and excellent insulation performance. The embodiment of the present invention uses a curing agent to undergo a cross-linking chemical reaction with the epoxy resin to generate a three-dimensional network solid polymer. It should be noted that the curing agent in the embodiment of the present invention has a great influence on the electrical and physical properties of the cured product and is a key component for curing the epoxy resin to form a hard polymer body. In addition, the embodiment of the present invention accelerates the chemical reaction rate between the epoxy resin and the curing agent through a accelerator to shorten the curing time of the epoxy resin.

[0026] In specific implementation, the epoxy resin described in the embodiment of the present invention is a combination of one or more weather-resistant epoxy resins such as hexahydrophthalic acid diglycidyl ester, 3,4-epoxycyclohexylcarboxylic acid-3', 4'-epoxycyclohexyl methyl ester, bis((3,4-epoxycyclohexyl)methyl)adipate, cyclohexane-1,2-dicarboxylic acid diglycidyl ester. The curing agent in the embodiment of the present invention is a combination of one or more of tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, succinic anhydride, and amino-terminated polyether. The accelerator can be a tertiary amine accelerator, etc.

[0027] Furthermore, in the embodiment of the present invention, the epoxy resin may be set to be diglycidyl hexahydrophthalate, the curing agent may be methyl hexahydrophthalic anhydride, and the accelerator may be N,N-dimethylbenzylamine. Of course, in the specific implementation, those skilled in the art may also set other epoxy resins, curing agents, accelerators, etc. according to actual needs, and the present invention does not specifically limit this.

[0028] In addition, the embodiments of the present invention utilize low molecular weight polyether to increase the cross-linking density of the cross-linking network, resist the invasion of water molecules, and reduce the saturated water absorption rate, and utilize the molecular chain segment activity of high molecular weight polyether to improve the mechanical toughness of the cross-linking network, and then compound polyether molecules of different molecular weights to achieve the synergy between the high cross-linking density and high mechanical toughness of the material of the present invention, ultimately making the weather-resistant synthetic material prepared by the present invention have higher operational reliability.

[0029] In a specific implementation, the second material in the embodiment of the present invention includes a first molecular weight polyether (i.e., a low molecular weight polyether), a second molecular weight polyether (i.e., a medium molecular weight polyether) and a third molecular weight polyether (i.e., a high molecular weight polyether), wherein the first molecular weight polyether is one or more of a polyether polyol and an epoxy-terminated polyether with a molecular weight of 200-500, the second molecular weight polyether is one or more of a polyether polyol and an epoxy-terminated polyether with a molecular weight of 500-1000, the third molecular weight polyether is one or more of a polyether polyol and an epoxy-terminated polyether with a molecular weight of 1000-5000, and the ratio of the first molecular weight polyether, the second molecular weight polyether and the third molecular weight polyether is 1:2:2.

[0030] Specifically, the low molecular weight polyether provided in the embodiment of the present invention is one or more of a polyether polyol with a molecular weight of 200-500 and an epoxy-terminated polyether, and the high molecular weight polyether provided is one or more of a polyether polyol with a molecular weight of 500-1000 and an epoxy-terminated polyether. Of course, it is also possible to further provide a medium molecular weight polyether as one or more of a polyether polyol with a molecular weight of 1000-5000 and an epoxy-terminated polyether on the basis of providing high and low molecular weight polyethers, and to set the ratio of the first molecular weight polyether, the second molecular weight polyether and the third molecular weight polyether to be 1:2:2, and then use the first molecular weight polyether, the second molecular weight polyether and the third molecular weight polyether to form a three-dimensional molecular cross-linked network with a certain chain activity ability and a dense structure, so as to achieve the best material mechanical toughness of the weather-resistant synthetic material and obtain the lowest water absorption rate. It should be noted that the high molecular weight polyether can be used as a long chain to form the main skeleton, while the medium and low molecular weight polyethers can be used as a long chain to form the main skeleton. Polyether can be used as a short chain to fill the gaps in the long chain. Experiments have shown that when the ratio of low, medium and high molecular weight polyether is less than 1:2:2, an incomplete continuous network will occur, resulting in poor impact strength. When the ratio of low, medium and high molecular weight polyether is greater than 1:2:2, the movement of long molecular chains will be hindered, and short molecular chains will easily form independent phases, which will lead to the final material having poor impact strength and high water absorption. When the ratio of low, medium and high molecular weight polyether is equal to 1:2:2, the material can obtain the highest impact strength and the lowest water absorption, thereby making the insulation product have better operational reliability.

[0031] Experiments show that when low and medium molecular weights are missing, the hinge network will be loose, which will lead to high water absorption. When high molecular weight is missing, the material's impact toughness will be poor. Therefore, after a large number of experiments, it was determined that the ratio of low, medium and high molecular weight polyethers is greater than 1:2:2. The compounding of polyether molecules with this ratio can effectively ensure that the final weather-resistant synthetic material constructs a three-dimensional cured cross-linked network with chain segment activity and density, thereby achieving a synergistic improvement in the mechanical toughness and low water absorption of weather-resistant epoxy insulation materials, thereby ultimately improving the operating reliability of insulation products.

[0032] It should be noted that the low molecular weight polyether described in the embodiments of the present invention is one or more of a polyether polyol and an epoxy-terminated polyether with a molecular weight of 200-500. It can be understood that the low molecular weight polyether in the present invention is a combination of polyether polyols and / or epoxy-terminated polyethers of different molecular weights, which can be arbitrarily set by a person skilled in the art, and the present invention does not specifically limit this. Similarly, the high molecular weight polyether and medium molecular weight polyether in the embodiments of the present invention are also various combinations of polyether polyols and / or epoxy-terminated polyethers at corresponding molecular weights.

[0033] In specific implementation, the aluminum hydroxide filler in the embodiment of the present invention is used as a flame retardant to improve the flame retardant performance of the insulator. The aluminum hydroxide filler can absorb heat and release water vapor when burning, thereby reducing the combustion temperature and diluting the combustible gas to achieve a flame retardant effect. At the same time, it can also be used as a filler to improve the anti-tracking performance of the insulator.

[0034] Furthermore, the silicon dioxide in the embodiment of the present invention can improve the insulation performance and mechanical strength of the epoxy resin.

[0035] In addition, the silane coupling agent in the embodiment of the present invention acts as a transition phase, bridging inorganic materials such as lithium hydroxide and silicon dioxide and organic materials such as epoxy resin. The silane coupling agent can improve the adhesion and compatibility between organic / inorganic materials, thereby enhancing the electromechanical properties, moisture resistance and chemical resistance of the insulating material.

[0036] In specific implementation, the embodiment of the present invention further optimizes the design of the weather-resistant synthetic material, including: 90-120 parts of epoxy resin, 60-120 parts of curing agent, 50-300 parts of aluminum hydroxide filler, 0.5-1.5 parts of accelerator, 2-5 parts of silane coupling agent and 50-300 parts of silicon dioxide, the first material accounts for 90-97 parts by weight of the epoxy resin, and the second material accounts for 3-10 parts by weight of the epoxy resin.

[0037] Practice has proved that the optimized weather-resistant synthetic material composition can better improve the mechanical toughness and low water absorption performance of weather-resistant epoxy insulation materials, so it can better improve the operational reliability of insulation products.

[0038] Furthermore, through a large number of experiments, the optimal weather-resistant synthetic material designed in the embodiment of the present invention is 100 parts of epoxy resin, 100 parts of curing agent, 280 parts of aluminum hydroxide filler, 1.5 parts of accelerator, 1 part of silane coupling agent and 80 parts of silicon dioxide. The first material accounts for 95 parts by weight of the epoxy resin, and the second material accounts for 5 parts by weight of the epoxy resin.

[0039] Tests show that the above-mentioned optimal weather-resistant synthetic materials can achieve the best material mechanical toughness and obtain the lowest water absorption.

[0040] In general, the present invention is based on the above-mentioned various materials, and a curing and cross-linking reaction occurs at high temperature to form a dense three-dimensional cured cross-linked network of epoxy resin containing micron inorganic fillers and having a certain molecular chain activity ability. This makes the weather-resistant synthetic material prepared by the present invention able to effectively ensure that the final prepared insulating product has excellent mechanical and electrical properties, thereby enabling the material of the present invention to be used as an insulating material for high-voltage electrical equipment.

[0041] The weather-resistant synthetic material described in the embodiment of the present invention will be explained and illustrated in detail by a specific example below: The present invention designs different impact strength and saturated water absorption experiments for experimental groups and control groups, wherein: Experimental group: There are 4 experimental groups, namely experimental groups 1 to 4. Experimental groups 1 to 4 respectively use the materials involved in experimental examples 1 to 4 to make specimens. Among them, the impact specimen is 120 mm long, 15 mm wide, and 10 mm thick, and the water absorption specimen is 50 mm in diameter and 2 mm thick.

[0042] Control group: There are 3 control groups, which also include epoxy resin, curing agent, accelerator, silane coupling agent, silicon dioxide, and aluminum hydroxide filler, and the weight proportions of each component correspond to those of experimental groups 1 to 4. The only difference is that the second material of the epoxy resin in control groups 1 to 3 does not have a multi-molecular weight synergistic combination; Control group 1: This embodiment involves a weather-resistant synthetic material external insulation product with good mechanical properties, which includes, by weight: 100 parts of epoxy resin, 100 parts of curing agent, 1.5 parts of accelerator, 1 part of silane coupling agent, 80 parts of silicon dioxide, and 280 parts of aluminum hydroxide filler; wherein the epoxy resin includes 95 parts of the first material by weight of the epoxy resin and 5 parts of the second material by weight of the epoxy resin, the first material is diglycidyl hexahydrophthalate, and the second material is a polyether polyol with a molecular weight of 500.

[0043] Control group 2: This embodiment involves a weather-resistant synthetic material external insulation product with good mechanical properties, which includes, by weight: 100 parts of epoxy resin, 100 parts of curing agent, 1.5 parts of accelerator, 1 part of silane coupling agent, 80 parts of silicon dioxide, and 280 parts of aluminum hydroxide filler; wherein the epoxy resin includes 95 parts of the first material by weight of the epoxy resin and 5 parts of the second material by weight of the epoxy resin, the first material is diglycidyl hexahydrophthalate, and the second material is a polyether polyol with a molecular weight of 1000.

[0044] Control group 3: This embodiment involves a weather-resistant synthetic material external insulation product with good mechanical properties, which includes, by weight: 100 parts of epoxy resin, 100 parts of curing agent, 1.5 parts of accelerator, 1 part of silane coupling agent, 80 parts of silicon dioxide, and 280 parts of aluminum hydroxide filler; wherein the epoxy resin includes 95 parts of the first material by weight of the epoxy resin and 5 parts of the second material by weight of the epoxy resin, the first material is diglycidyl hexahydrophthalate, and the second material is a polyether polyol with a molecular weight of 2000.

[0045] Experimental Group 1: This embodiment involves a weather-resistant synthetic material external insulation product with good mechanical properties, which includes, by weight: 100 parts of epoxy resin, 100 parts of curing agent, 1.5 parts of accelerator, 1 part of silane coupling agent, 80 parts of silicon dioxide, and 280 parts of aluminum hydroxide filler; wherein the epoxy resin includes 95 parts of the first material by weight of the epoxy resin and 5 parts of the second material by weight of the epoxy resin, the first material is diglycidyl hexahydrophthalate, and the second material is 2 parts of a polyether polyol with a molecular weight of 500 and 3 parts of a polyether polyol with a molecular weight of 1000.

[0046] Experimental Group 2: This embodiment involves a weather-resistant synthetic material external insulation product with good mechanical properties, which includes, by weight: 100 parts of epoxy resin, 100 parts of curing agent, 1.5 parts of accelerator, 1 part of silane coupling agent, 80 parts of silicon dioxide, and 280 parts of aluminum hydroxide filler; wherein the epoxy resin includes 95 parts of the first material by weight of the epoxy resin and 5 parts of the second material by weight of the epoxy resin, the first material is diglycidyl hexahydrophthalate, and the second material is 2 parts of a polyether polyol with a molecular weight of 500, 3 parts of a polyether polyol with a molecular weight of 800, and 3 parts of a polyether polyol with a molecular weight of 2000.

[0047] Experimental Group 3: This embodiment involves a weather-resistant synthetic material external insulation product with good mechanical properties, which includes, by weight: 100 parts of epoxy resin, 100 parts of curing agent, 1.5 parts of accelerator, 1 part of silane coupling agent, 80 parts of silica, and 280 parts of aluminum hydroxide filler; wherein the epoxy resin includes 95 parts of a first material by weight of the epoxy resin and 5 parts of a second material by weight of the epoxy resin, the first material is diglycidyl hexahydrophthalate, and the second material is 2 parts of a polyether polyol with a molecular weight of 1000, 3 parts of a polyether polyol with a molecular weight of 900, and 3 parts of a polyether polyol with a molecular weight of 2000.

[0048] Experimental Group 4: This embodiment involves a weather-resistant synthetic material external insulation product with good mechanical properties, which includes, by weight: 100 parts of epoxy resin, 100 parts of curing agent, 1.5 parts of accelerator, 1 part of silane coupling agent, 80 parts of silica, and 280 parts of aluminum hydroxide filler; wherein the epoxy resin includes 95 parts of a first material by weight of the epoxy resin and 5 parts of a second material by weight of the epoxy resin, the first material is diglycidyl hexahydrophthalate, and the second material is 1 part of a polyether polyol with a molecular weight of 500, 2 parts of a polyether polyol with a molecular weight of 1000, and 2 parts of a polyether polyol with a molecular weight of 2000.

[0049] Table 1 Experimental results of impact strength and saturated water absorption of each experimental group and control group As shown in Table 1, the experimental group of the present invention is provided with a reasonable combination of polyether organic substances of different molecular weights, while the control group is only one polyether organic substance and does not involve a reasonable combination of polyether organic substances. Therefore, by comparison, the weather-resistant synthetic material using a reasonable combination of polyether organic substances has better impact resistance and low water absorption.

[0050] In summary, the embodiments of the present invention achieve a synergistic improvement in the mechanical toughness and low water absorption of weather-resistant epoxy insulation materials by coordinating polyether organic substances of different molecular weights to construct a dense three-dimensional cured cross-linked network with segment activity. This ultimately effectively improves the operational reliability of the insulation product.

[0051] Accordingly, an embodiment of the present invention further provides a method for preparing any of the weather-resistant synthetic materials described above, the method comprising: According to weight percentage, 90 to 170 parts of epoxy resin, 60 to 170 parts of curing agent, 0.1 to 2 parts of accelerator and 2 to 6 parts of silane coupling agent are sequentially placed in a container, and the solution in the container is fully stirred and mixed at a first stirring speed; Divide 50 to 300 parts of aluminum hydroxide filler into multiple parts, slowly pour them into the container in batches, and stir and mix them thoroughly at the second stirring speed; 50 to 300 parts of silica filler are placed in the container and are fully stirred and mixed at a third stirring speed. The polyether molecules of the second material are compounded to form a three-dimensional solidified cross-linked network with segment mobility and density, thereby finally obtaining the weather-resistant synthetic material.

[0052] In specific implementation, the first stirring speed can be set to 400-500 rpm; the second stirring speed can be set to 1000-1200 rpm; and the third stirring speed can be set to 1400-1500 rpm. Of course, those skilled in the art can set specific stirring speeds according to actual needs, and the present invention does not specifically limit this.

[0053] That is to say, the present invention is a combination of multiple polyether organic substances with different molecular weights, and through the coordination between the various components, the material forms a dense three-dimensional molecular cross-linked network with certain chain segment movement ability, thereby solving the problems of low toughness and high water absorption of weather-resistant epoxy resin insulation materials, and achieving a synergistic improvement in mechanical toughness and low water absorption performance.

[0054] Furthermore, an embodiment of the present invention also provides a novel weather-resistant composite external insulator, that is, the weather-resistant synthetic material obtained by the above method is subjected to APG injection molding process to obtain the novel weather-resistant composite external insulator.

[0055] In specific implementation, the embodiment of the present invention adopts the automatic pressure gelation process (APG) for injection molding, and the evenly stirred mixture undergoes a curing and cross-linking chemical reaction at high temperature to form a dense and tough three-dimensional cross-linked network. After the insulation is completed, the insulation product is taken out from the mold and placed in an oven for secondary curing to eliminate internal stress, and finally a weather-resistant epoxy resin insulation product with excellent mechanical toughness and low water absorption is obtained.

[0056] Among them, the pressure of APG injection molding is 0.2~0.8MPa, the temperature of the mold for the first curing molding is 100~160℃, and the insulation time is 20~60min; After the insulation time is over, the second curing molding is carried out, wherein the temperature of the mold for the second curing molding is 100-150° C., and the time of the second curing molding is 3-10 hours, and finally a new weather-resistant composite external insulator is prepared.

[0057] During actual use, the novel weather-resistant composite external insulator of the present invention indeed achieves a synergistic improvement in the mechanical toughness and low water absorption of the weather-resistant epoxy insulation material, so the novel weather-resistant composite external insulator of the present invention can effectively improve the operating reliability of the insulation product.

[0058] It should be noted that the stirring speed, stirring time, APG curing molding parameters, and secondary curing parameters in the embodiments of the present invention can be adjusted according to the actual stirring conditions, and the present invention does not specifically limit this.

[0059] Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, and thus, the scope of the present invention should not be limited to the above embodiments.

Claims

1. A weather-resistant synthetic material with good mechanical properties, characterized in that: The weather-resistant synthetic material comprises, by weight: 90 to 170 parts of epoxy resin, 60 to 170 parts of curing agent, 50 to 300 parts of aluminum hydroxide filler, 0.1 to 2 parts of accelerator, 2 to 6 parts of silane coupling agent and 50 to 300 parts of silicon dioxide; Among them, in terms of weight parts, the epoxy resin includes 50 to 98 parts of the first material and 2 to 50 parts of the second material, the first material is a combination of one or more of hexahydrophthalic acid diglycidyl ester, 3,4-epoxycyclohexylcarboxylic acid-3', 4'-epoxycyclohexyl methyl ester, bis((3,4-epoxycyclohexyl)methyl)adipate and cyclohexane-1,2-dicarboxylic acid diglycidyl ester, and the second material is polyether polyols of different molecular weights and / or terminal epoxy polyethers of different molecular weights. Through the compounding of the polyether molecules in the second material, the weather-resistant synthetic material is constructed to obtain a dense three-dimensional cured cross-linked network with segment activity.

2. The weather-resistant synthetic material according to claim 1, characterized in that: Calculated by weight, the weather-resistant synthetic material includes: 90-120 parts of epoxy resin, 60-120 parts of curing agent, 50-300 parts of aluminum hydroxide filler, 0.5-1.5 parts of accelerator, 2-5 parts of silane coupling agent and 50-300 parts of silicon dioxide.

3. The weather-resistant synthetic material according to claim 2, characterized in that: Calculated by weight, the weather-resistant synthetic material includes: 100 parts of epoxy resin, 100 parts of curing agent, 280 parts of aluminum hydroxide filler, 1.5 parts of accelerator, 1 part of silane coupling agent and 80 parts of silicon dioxide.

4. The weather-resistant synthetic material according to any one of claims 1 to 3, characterized in that: The first material accounts for 90 to 97 parts by weight of the epoxy resin, and the second material accounts for 3 to 10 parts by weight of the epoxy resin.

5. The weather-resistant synthetic material according to claim 4, characterized in that: The first material accounts for 95 parts by weight of the epoxy resin, and the second material accounts for 5 parts by weight of the epoxy resin.

6. The weather-resistant synthetic material according to claim 4, characterized in that: The second material includes a first molecular weight polyether, a second molecular weight polyether and a third molecular weight polyether, wherein the first molecular weight polyether is one or more of a polyether polyol with a molecular weight of 200-500 and a terminal epoxy polyether, the second molecular weight polyether is one or more of a polyether polyol with a molecular weight of 500-1000 and a terminal epoxy polyether, the third molecular weight polyether is one or more of a polyether polyol with a molecular weight of 1000-5000 and a terminal epoxy polyether, and the ratio of the first molecular weight polyether, the second molecular weight polyether and the third molecular weight polyether is 1:2:

2.

7. The weather-resistant synthetic material according to any one of claims 1 to 3, characterized in that: The curing agent is a combination of one or more of tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, succinic anhydride and amino-terminated polyether; The curing agent is methyl hexahydrophthalic anhydride; The silicon dioxide is micron silicon dioxide.

8. A method for preparing the weather-resistant synthetic material according to any one of claims 1 to 7, characterized in that: The method comprises: According to weight percentage, 90 to 170 parts of epoxy resin, 60 to 170 parts of curing agent, 0.1 to 2 parts of accelerator and 2 to 6 parts of silane coupling agent are sequentially placed in a container, and the solution in the container is fully stirred and mixed at a first stirring speed; Divide 50 to 300 parts of aluminum hydroxide filler into multiple parts, slowly pour them into the container in batches, and stir and mix them thoroughly at the second stirring speed; 50 to 300 parts of silica filler are placed in the container and are fully stirred and mixed at a third stirring speed. The polyether molecules of the second material are compounded to form a three-dimensional solidified cross-linked network with segment mobility and density, thereby finally obtaining the weather-resistant synthetic material.

9. A novel weather-resistant composite external insulator, characterized in that: The novel weather-resistant composite external insulator is obtained by using the weather-resistant synthetic material obtained as claimed in claim 8 through automatic pressure gel molding process APG injection molding.

10. The novel weather-resistant composite outer insulator according to claim 9, characterized in that: The pressure of APG injection molding is 0.2~0.8MPa, the temperature of the mold for the first curing molding is 100~160℃, and the insulation time is 20~60min; After the insulation time is over, the second curing molding is carried out, wherein the temperature of the mold for the second curing molding is 100-150° C., and the time of the second curing molding is 3-10 hours, and finally a new weather-resistant composite external insulator is prepared.

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