Flexible insulating plate based on bromine-containing epoxy resin and preparation method thereof

Abstract

The invention relates to the technical field of resin processing and preparation, and particularly discloses a flexible insulating plate based on bromine-containing epoxy resin and a preparation method of the flexible insulating plate. The flexible insulating plate based on bromine-containing epoxy resin is prepared from the following raw materials in parts by weight: 90-100 parts of bromine-containing epoxy resin; 10-15 parts of a curing agent; 0.4 to 1 part of a curing accelerator; 20 to 30 parts of a diluent; 20 to 30 parts of filler; 0.1 to 0.5 part of a defoaming agent; and 4-6 parts of a dispersant. The preparation method comprises the following steps: putting the bromine-containing epoxy resin into a reaction container, adding the diluent, the filler, the defoaming agent and the dispersing agent, uniformly mixing, and adding the curing agent and the curing accelerator to obtain a mixture; and putting the mixture into a mold for high-temperature curing, and cooling and demolding after curing is completed. The flexible insulating plate based on the bromine-containing epoxy resin can show better flexibility and can be stably used for a long time under the action of external force.

Description

Technical Field

[0001] The present application relates to the technical field of resin processing and preparation, and more specifically, to a flexible insulating board based on brominated epoxy resin and a preparation method thereof. Background Art

[0002] An insulating board, also known as an insulating rubber mat, insulating pad, insulating gasket or insulating blanket, is a product made of a rubber-like insulating material and is widely used in substations, power plants, distribution rooms, laboratories, and live working outdoors, etc. Its main function is to provide electrical isolation, prevent current leakage or short circuit, and ensure the safety of operators.

[0003] Insulating boards are usually made of rubber-like insulating materials. Epoxy resin is a polymer material with excellent properties. It has advantages such as thermal stability, chemical stability, high mechanical strength, and good insulation performance, and is usually one of the common raw materials in insulating boards. At the same time, brominated epoxy resin is obtained by introducing bromine atoms into the molecular structure of epoxy resin. It is also called brominated epoxy resin or bromoepoxy resin, and has good self-extinguishing and heat resistance properties, and can provide excellent flame retardant and electrical insulation properties, making it have significant advantages in insulating boards.

[0004] Regarding the above related technologies, the inventor believes that the molecular chain structure in brominated epoxy resin is very tight, with a large molecular weight and high cross-linking degree, which restricts the molecular spacing and limits the movement space of the molecular chain, resulting in the insulating board made of brominated epoxy resin often being a rigid board with poor flexibility. And affected by various complex environments, during installation and use, the insulating board may be subjected to various external forces. Good flexibility can effectively disperse stress and reduce stress concentration, thereby prolonging the service life.

[0005] Therefore, there is an urgent need to propose a solution to solve the above technical problems. Summary of the Invention

[0006] In order to enable the insulating board containing brominated epoxy resin to exhibit better flexibility and thus be used stably for a long time under external forces, the present application provides a flexible insulating board based on brominated epoxy resin and a preparation method thereof.

[0007] In the first aspect, the present application provides a flexible insulating board based on brominated epoxy resin, adopting the following technical solution: A flexible insulating board based on brominated epoxy resin is made of raw materials comprising the following parts by weight: Brominated epoxy resin 90 - 100 parts; Curing agent 10 - 15 parts; Curing accelerator 0.4 - 1 part; Diluent 20 - 30 parts; 20 - 30 parts of filler; 0.1 - 0.5 part of defoamer; 4 - 6 parts of dispersant; The brominated epoxy resin is obtained by the following method: S1. After mixing tetrabromobisphenol A and epichlorohydrin, add a first catalyst and stir for etherification reaction, then add toluene solvent and sodium hydroxide solution for reaction. After the reaction ends, let it stand for stratification, remove the aqueous phase, and obtain a brominated epoxy resin polymerization intermediate; S2. After mixing the brominated epoxy resin polymerization intermediate obtained in step S1 and tetrabromobisphenol A, heat and melt, add a second catalyst for polymerization reaction to obtain an initial brominated epoxy resin product; S3. React toluene diisocyanate and polypropylene glycol to obtain a modifier; then mix the initial brominated epoxy resin product obtained in step S2 and the modifier, add a third catalyst and heat for reaction to obtain a brominated epoxy resin.

[0008] By adopting the above technical solution, in the preparation of the brominated epoxy resin, first use tetrabromobisphenol A and epichlorohydrin to obtain a brominated epoxy resin polymerization intermediate by the method of first etherification and then cyclization; then add tetrabromobisphenol A, add a catalyst, heat for reaction and chain extension to obtain an initial brominated epoxy resin product; finally, use the modifier obtained by reacting toluene diisocyanate and polypropylene glycol for catalytic polymerization reaction. In this way, the obtained brominated epoxy resin not only has a high molecular weight, qualified bromine content, and excellent high - heat stability, but also by introducing polyether flexible chain segments between the brominated epoxy resin chain segments, the flexible chain segments can be evenly distributed in the cross - linked network formed after the brominated epoxy resin is cured, thereby forming a two - phase network structure with alternating tight and loose phases, making the stress - dispersing ability of the flexible insulating board based on the brominated epoxy resin significantly improved, the overall flexibility enhanced, and it can be used stably for a long time under external force.

[0009] Preferably, in step S1, the molar ratio of tetrabromobisphenol A to epichlorohydrin is 1:(0.4 - 0.5).

[0010] By adopting the above technical solution, the above - mentioned amounts of tetrabromobisphenol A and epichlorohydrin are easy to control the reaction during etherification and cyclization, and thus a brominated epoxy resin polymerization intermediate with high purity and high yield can be obtained, indicating that the amount of by - products generated during the process is relatively low, and it is also easy to use further subsequently, ensuring the excellent quality of the finally obtained brominated epoxy resin.

[0011] Preferably, in step S2, the mass mixing ratio of the brominated epoxy resin polymerization intermediate to tetrabromobisphenol is (1.1 - 1.3):1.

[0012] By adopting the above technical solution, during the application process of the brominated epoxy resin polymerization intermediate and tetrabromobisphenol with the above dosage ratio, an initial brominated epoxy resin product with a moderate molecular weight can be obtained, with an average molecular weight of 30,000 - 4,000. It is easy for the polyether flexible segment to be introduced into the brominated epoxy resin segment completely and evenly during the subsequent mixing reaction with the modifier, and then a brominated epoxy resin with better application quality can be obtained.

[0013] Preferably, in step S3, the molar ratio of toluene diisocyanate to polypropylene glycol is (1.8 - 2.2):1.

[0014] By adopting the above technical solution, the modifier obtained by reacting toluene diisocyanate and polypropylene glycol with the above dosage ratio has better adaptability between the introduced polyether flexible segment and the brominated epoxy resin segment during the application process, and thus the brominated epoxy resin shows better performance in the flexibility expression and stress dispersion of the network structure.

[0015] Preferably, in step S3, the mass mixing ratio of the initial brominated epoxy resin product to the modifier is (2.8 - 3.2):1.

[0016] By adopting the above technical solution, after the interaction between the initial brominated epoxy resin product and the modifier with the above dosage ratio, the polyether flexible segments are distributed more evenly between the brominated epoxy resin segments. And in the crosslinked network formed after the curing of the brominated epoxy resin, the appropriate amount of introduced polyether flexible segments can also ensure the crosslinking density of the brominated epoxy resin. Thus, on the premise of showing good flexibility, the finally obtained flexible insulating board can also maintain a high structural strength, and its overall stability under external forces is excellent.

[0017] Preferably, 4 - 8 parts by weight of a functional additive are further added to the raw materials. The functional additive is composed of modified organic clay and seaweed fiber, and the weight ratio of modified organic clay to seaweed fiber is 1:(1.4 - 1.8); The modified organic clay is obtained by the following method: Take the sodium-based clay raw material, disperse it in deionized water, add cetyltrimethylammonium bromide and lanthanum oxide after heating, stir and react, and then obtain the modified organic clay through filtration, washing and drying.

[0018] By adopting the above technical solutions, when the prepared modified organic clay is applied, its unique lamellar structure can be uniformly dispersed in the brominated epoxy resin and form an intercalated hybrid structure, and a strong interfacial bond is formed with the brominated epoxy resin matrix. At the same time, by utilizing the thermal stability and interfacial improvement effect brought by lanthanum oxide, the modified organic clay can act as a stable physical crosslinking point in the network structure of the brominated epoxy resin, thereby further enhancing the impact toughness of the flexible insulating board. The seaweed fiber has a relatively high heat-resistant temperature and can stably exist in the flexible insulating board. Through its own physical and chemical crosslinking effects, the flexibility is improved. At the same time, when the modified organic clay and the seaweed fiber are used as functional additives, they can play an excellent compound synergistic effect with each other. By combining the lamellar-structured organic clay with the seaweed fiber, a three-dimensional structure is constructed in the crosslinked network after the brominated epoxy resin is cured, and this structure can adapt to and regulate the movement of the molecular chains of the brominated epoxy resin under stress, thereby making the flexibility of the flexible insulating board better expressed and enabling it to be used more stably for a longer time under external forces.

[0019] Preferably, the weight ratio of the modified organic clay to the seaweed fiber is 1:1.6.

[0020] By adopting the above technical solutions, when the above-mentioned weights of the modified organic clay and the seaweed fiber are combined, the structural system they construct in the cured crosslinked network of the brominated epoxy resin is relatively uniform and moderate, and can exert better corresponding effects, and finally a flexible insulating board with better quality can be obtained.

[0021] Preferably, in the preparation of the modified organic clay, the mass mixing ratio of the sodium-based clay raw material, cetyltrimethylammonium bromide, and lanthanum oxide is (2 - 2.6):1:(0.1 - 0.3).

[0022] By adopting the above technical solutions, during the application and combination process of the above raw materials, lanthanum oxide can be uniformly distributed in the lamellar structure of the clay. Through the modification effect of cetyltrimethylammonium bromide, the physical crosslinking point effect brought by the modified organic clay in the network structure of the brominated epoxy resin is better manifested; at the same time, the corresponding effects brought by the combination of the modified organic clay and the seaweed fiber are also better; thus, after the functional additive is applied, a flexible insulating board with better quality can be obtained.

[0023] Preferably, the mass mixing ratio of the sodium-based clay raw material, cetyltrimethylammonium bromide, and lanthanum oxide is 2.3:1:0.2.

[0024] By adopting the above technical solutions, when the sodium-based clay raw material, cetyltrimethylammonium bromide, and lanthanum oxide in the above ratio are used in combination, the corresponding effects exerted by the obtained modified organic clay in application are better.

[0025] In a second aspect, the present application provides a method for preparing a flexible insulating board based on brominated epoxy resin, adopting the following technical solution: A method for preparing a flexible insulating board based on brominated epoxy resin, comprising the following steps: (1) Prepare raw materials including brominated epoxy resin, curing agent, curing accelerator, diluent, filler, defoaming agent, and dispersant according to the ratio; (2) Place the brominated epoxy resin in step (1) in a reaction vessel, then add the diluent, filler, defoaming agent, and dispersant and mix evenly, and then add the curing agent and curing accelerator to obtain a mixture; (3) Put the mixture in step (2) into a mold for high-temperature curing, and after curing is completed, cool and demold to obtain a flexible insulating board based on brominated epoxy resin.

[0026] By adopting the above technical solution, the operation of the above preparation method is relatively simple. Only by mixing the raw materials, the brominated epoxy resin and other raw materials can exert excellent and stable cooperation effects during application, which is beneficial to obtaining a flexible insulating board based on brominated epoxy resin with excellent and stable quality, and the whole is more suitable for large-scale industrial production.

[0027] In summary, the present application has the following beneficial effects: 1. After the initial product of brominated epoxy resin is prepared in the present application, the polyether flexible chain segment is introduced between the brominated epoxy resin chain segments, so that the flexible chain segments can be evenly distributed in the cross-linked network formed after the brominated epoxy resin is cured, and then a two-phase network structure with a tight and loose phase is formed, which significantly improves the stress dispersion ability of the flexible insulating board based on brominated epoxy resin, enhances the overall flexibility, and can be used stably for a long time under external force; 2. In the present application, by adding a functional additive composed of modified organic clay and seaweed fiber, and utilizing the compounding effect brought by the two, a three-dimensional structure is constructed in the cross-linked network after the brominated epoxy resin is cured by the cooperation of the organic clay with a lamellar structure and the seaweed fiber to adjust the movement of the brominated epoxy resin molecular chain under stress, so that the flexibility of the flexible insulating board is better expressed and can also be used stably for a longer time under external force. Specific Embodiments

[0028] The present application will be further described in detail below with reference to preparation examples, examples, and comparative examples.

[0029] The raw materials used in each preparation example, example, and comparative example of the present application are all commercially available except as otherwise specified.

[0030] The curing agent is a dicyandiamide-based curing agent, purchased from Huntsman Omicure U-52M; The curing accelerator is an imidazole curing accelerator, which is 1-cyanoethyl-2-ethyl-4-methylimidazole 2E4MZ-CN from Shikoku Chemical of Japan; The diluent is acetone; The filler is barium sulfate, purchased from Aoda BD-702; The defoamer was purchased from BYK-A535; The dispersant was purchased from EFKA-5210; Polypropylene glycol was purchased from Nantong Yongle Chemical Co., Ltd. as polypropylene glycol PPG2000; The sodium-based clay raw material was purchased from Hebei Guanchuan New Material Technology Co., Ltd., with a specification of 200 mesh; Seaweed fiber was purchased from Qingdao Hailan Biological Products Co., Ltd., item number hzd0001.

[0031] Preparation examples of raw materials and / or intermediates Preparation Example 1 A bromine-containing epoxy resin is prepared by the following method: S1, after tetrabromobisphenol A and epichlorohydrin are mixed, the first catalyst is added and stirred at 120r / min for etherification reaction, and the reaction is carried out at 75°C for 3h, and then a toluene solvent with a mass of 60% of the mass of tetrabromobisphenol A and a sodium hydroxide solution with a concentration of 35% are added for reaction, and the mass of the sodium hydroxide solution is 60% of the mass of tetrabromobisphenol A. After the reaction is completed for 4h, the mixture is allowed to stand for stratification, and the aqueous phase is removed to obtain a bromine-containing epoxy resin polymerization intermediate; S2, mixing the bromine-containing epoxy resin polymer intermediate obtained in step S1 with tetrabromobisphenol A, heating to 150° C. to melt, adding a second catalyst to carry out polymerization reaction for 8.5 hours, and obtaining an initial bromine-containing epoxy resin product; S3, mixing toluene diisocyanate and polypropylene glycol at 70° C. for 3 hours to obtain a modifier; then mixing the initial product of the bromine-containing epoxy resin obtained in step S2 with the modifier, adding a third catalyst for heating reaction, and reacting at 70° C. for 2 hours to obtain a bromine-containing epoxy resin.

[0032] Note: In the above operation, the first catalyst is tetramethylammonium chloride, the second catalyst is triphenylphosphine, the third catalyst is dibutyltin dilaurate, and the above catalysts account for 0.3% of the mixed mass of the reaction system; at the same time, in step S1, the molar ratio of tetrabromobisphenol A to epichlorohydrin is 1:0.45; in step S2, the mass mixing ratio of the bromine-containing epoxy resin polymer intermediate and tetrabromobisphenol is 1.2:1; in step S3, the molar ratio of toluene diisocyanate and polypropylene glycol is 2:1, and the mass mixing ratio of the bromine-containing epoxy resin initial product and the modifier is 3:1.

[0033] Preparation Example 2 A brominated epoxy resin, which is different from Preparation Example 1 in that in step S1, the molar ratio of tetrabromobisphenol A to epichlorohydrin is 1:0.4.

[0034] Preparation Example 3 A brominated epoxy resin, which is different from Preparation Example 1 in that in step S1, the molar ratio of tetrabromobisphenol A to epichlorohydrin is 1:0.5.

[0035] Preparation Example 4 A brominated epoxy resin, which is different from Preparation Example 1 in that in step S2, the mass mixing ratio of the brominated epoxy resin polymerization intermediate to tetrabromobisphenol is 1.1:1.

[0036] Preparation Example 5 A brominated epoxy resin, which is different from Preparation Example 1 in that in step S2, the mass mixing ratio of the brominated epoxy resin polymerization intermediate to tetrabromobisphenol is 1.3:1.

[0037] Preparation Example 6 A brominated epoxy resin, which is different from Preparation Example 1 in that in step S3, the molar ratio of toluene diisocyanate to polypropylene glycol is 1.8:1.

[0038] Preparation Example 7 A brominated epoxy resin, which is different from Preparation Example 1 in that in step S3, the molar ratio of toluene diisocyanate to polypropylene glycol is 2.2:1.

[0039] Preparation Example 8 A brominated epoxy resin, which is different from Preparation Example 1 in that in step S3, the mass mixing ratio of the brominated epoxy resin initial product to the modifier is 2.8:1.

[0040] Preparation Example 9 A brominated epoxy resin, which is different from Preparation Example 1 in that in step S3, the mass mixing ratio of the brominated epoxy resin initial product to the modifier is 3.2:1.

[0041] Preparation Example 10 A modified organic clay is obtained by the following method: Take the sodium-based clay raw material and disperse it in deionized water at a ratio of 1 g:200 mL. After heating to 80 °C, add cetyltrimethylammonium bromide and lanthanum oxide, and stir and react at 100 r / min for 5 h. After filtration, washing and drying, the modified organic clay is obtained.

[0042] Note: In the above operation, the mass mixing ratio of the sodium-based clay raw material, cetyltrimethylammonium bromide and lanthanum oxide is 2.3:1:0.2.

[0043] Preparation Example 11 A modified organic clay, which is different from Preparation Example 10 in that the mass mixing ratio of the sodium-based clay raw material, cetyltrimethylammonium bromide, and lanthanum oxide is 2:1:0.1.

[0044] Preparation Example 12 A modified organic clay, which is different from Preparation Example 10 in that the mass mixing ratio of the sodium-based clay raw material, cetyltrimethylammonium bromide, and lanthanum oxide is 2.6:1:0.3.

[0045] Examples Example 1 A flexible insulating board based on brominated epoxy resin, the components required for its preparation and their corresponding weights are shown in Table 1, and it is obtained through the following steps: (1) Prepare raw materials including brominated epoxy resin, curing agent, curing accelerator, diluent, filler, defoaming agent, and dispersant according to the ratio; (2) Place the brominated epoxy resin in step (1) in a reaction vessel, then add the diluent, filler, defoaming agent, and dispersant and mix evenly, and then add the curing agent and curing accelerator to obtain a mixture; (3) Put the mixture in step (2) into a mold for high-temperature curing, and after curing is completed, cool and demold to obtain a flexible insulating board based on brominated epoxy resin.

[0046] Note: In the above operations, the brominated epoxy resin is obtained from Preparation Example 1.

[0047] Examples 2 - 3 A flexible insulating board based on brominated epoxy resin, which is different from Example 1 in that the components required for its preparation and their corresponding weights are shown in Table 1.

[0048] Table 1 Components and weight parts required for the preparation of Examples 1 - 3 (kg / part) Example 4 A flexible insulating board based on brominated epoxy resin, which is different from Example 1 in that the brominated epoxy resin is obtained from Preparation Example 2.

[0049] Example 5 A flexible insulating board based on brominated epoxy resin, which is different from Example 1 in that the brominated epoxy resin is obtained from Preparation Example 3.

[0050] Example 6 A flexible insulating board based on brominated epoxy resin, which is different from Example 1 in that the brominated epoxy resin is obtained from Preparation Example 4.

[0051] Example 7 A flexible insulating board based on brominated epoxy resin, which is different from that of Example 1 in that the brominated epoxy resin is obtained from Preparation Example 5.

[0052] Example 8 A flexible insulating board based on brominated epoxy resin, which is different from that of Example 1 in that the brominated epoxy resin is obtained from Preparation Example 6.

[0053] Example 9 A flexible insulating board based on brominated epoxy resin, which is different from that of Example 1 in that the brominated epoxy resin is obtained from Preparation Example 7.

[0054] Example 10 A flexible insulating board based on brominated epoxy resin, which is different from that of Example 1 in that the brominated epoxy resin is obtained from Preparation Example 8.

[0055] Example 11 A flexible insulating board based on brominated epoxy resin, which is different from that of Example 1 in that the brominated epoxy resin is obtained from Preparation Example 9.

[0056] Example 12 A flexible insulating board based on brominated epoxy resin, which is different from that of Example 1 in that the brominated epoxy resin is obtained from Preparation Example 10.

[0057] Example 13 A flexible insulating board based on brominated epoxy resin, which is different from that of Example 1 in that 6 parts by weight of a functional additive is further added to the raw materials. The functional additive is composed of modified organic clay and seaweed fiber in a weight ratio of 1:1.6. The modified organic clay is obtained from Preparation Example 10, and the functional additive is added and used together with a diluent, a filler, an antifoaming agent, and a dispersant during use.

[0058] Example 14 A flexible insulating board based on brominated epoxy resin, which is different from that of Example 13 in that the amount of the functional additive added is 4 parts by weight.

[0059] Example 15 A flexible insulating board based on brominated epoxy resin, which is different from that of Example 13 in that the amount of the functional additive added is 8 parts by weight.

[0060] Example 16 A flexible insulating board based on brominated epoxy resin, which is different from that of Example 13 in that the functional additive is composed of modified organic clay and seaweed fiber in a weight ratio of 1:1.4.

[0061] Example 17 A flexible insulating board based on brominated epoxy resin, which is different from Example 13 in that the functional additives are composed of modified organic clay and seaweed fiber in a weight ratio of 1:1.8.

[0062] Example 18 A flexible insulating board based on brominated epoxy resin, which is different from Example 13 in that the modified organic clay is obtained from Preparation Example 11.

[0063] Example 19 A flexible insulating board based on brominated epoxy resin, which is different from Example 13 in that the modified organic clay is obtained from Preparation Example 12.

[0064] Example 20 A flexible insulating board based on brominated epoxy resin, which is different from Example 13 in that the modified organic clay is not used in the raw materials.

[0065] Example 21 A flexible insulating board based on brominated epoxy resin, which is different from Example 13 in that the seaweed fiber is not used in the raw materials.

[0066] Comparative Example Comparative Example 1 A flexible insulating board based on brominated epoxy resin, which is different from Example 1 in that the brominated epoxy resin is prepared by the following method: Mix tetrabromobisphenol A, epichlorohydrin, and toluene solvent and heat to dissolve to obtain a raw material mixed solution. Then add a catalyst and react at 70°C for 1.5 h, and then add an alkaline solution and react at 65°C for 3 h to obtain brominated epoxy resin; In the above operations, the amounts of tetrabromobisphenol A, epichlorohydrin, and toluene solvent are the same as those in Preparation Example 1; the catalyst is tetrabutylammonium bromide, and the addition amount is 1% of the mass of tetrabromobisphenol A; the alkaline solution is a 35% sodium hydroxide solution, and the mass of the sodium hydroxide solution is 60% of the mass of tetrabromobisphenol A.

[0067] Performance Detection Test Test Samples: The flexible insulating boards based on brominated epoxy resin obtained in Examples 1 - 21 are used as Test Samples 1 - 21, and the flexible insulating board based on brominated epoxy resin obtained in Comparative Example 1 is used as Control Sample 1. The length and width of the above-mentioned obtained insulating boards are 1000 * 2000 mm, and the thickness is 5 mm.

[0068] Test methods: (1) Impact test method. By simulating impacts to measure the impact strength of the insulating board, it is an index for evaluating the performance of materials when suddenly subjected to impacts or strikes. During the process, an impact strength testing machine is used to evaluate whether the insulating board is easily damaged when subjected to accidental impacts in actual applications.

[0069] (2) Tensile test method. Tensile test is one of the most commonly used methods for detecting the flexibility of epoxy resins. It can evaluate the performance of materials before tensile failure. During the process, a tensile testing machine is used. Through the tensile test, it can be determined whether the epoxy resin has sufficient flexibility.

[0070] After the above tests are completed on test samples 1 - 21 and control sample 1 in sequence, the corresponding results are recorded in Table 2.

[0071] Table 2 Test results of test samples 1 - 21 and control sample 1 Combined with Example 1 and Comparative Example 1 and Table 2, it can be seen that in this application, after obtaining the brominated epoxy resin initial product, the polyether flexible chain segment is introduced between the brominated epoxy resin chain segments. After the obtained brominated epoxy resin is applied to the insulating board, the impact strength and tensile strength obtained through the above tests are both excellent; compared with the brominated epoxy resin directly polymerized from tetrabromobisphenol A and epichlorohydrin in an alkaline medium through a catalyst in Comparative Example 1, the flexible insulating board based on the brominated epoxy resin has obvious improvements in flexibility and impact resistance. This shows that through the specially prepared brominated epoxy resin in this application, the insulating board can exhibit better flexibility and be stably used for a long time under external forces, and the overall corresponding performance is significantly improved.

[0072] Combined with Example 1 and Examples 4 - 12 and Table 2, it can be seen that during the preparation process of the brominated epoxy resin, controlling the molar ratio of tetrabromobisphenol A to epichlorohydrin to be 1:(0.4 - 0.5), the mass mixing ratio of the brominated epoxy resin polymerization intermediate to tetrabromobisphenol to be (1.1 - 1.3):1, the molar ratio of toluene diisocyanate to polypropylene glycol to be (1.8 - 2.2):1, and the mass mixing ratio of the brominated epoxy resin initial product to the modifier to be (2.8 - 3.2):1 can all obtain brominated epoxy resins with better application quality, and make the brominated epoxy resin perform better in the flexibility expression and stress dispersion of the network structure.

[0073] Combined with Example 1 and Examples 13-17 and Table 2, it can be seen that by adding a functional additive composed of modified organic clay and seaweed fiber, the impact strength and tensile strength of the flexible insulating board can be further improved, indicating that the flexibility of the flexible insulating board is better expressed and it can be used more stably for a longer time under external forces. Further combined with Examples 18-19 and Table 2, it can be seen that in the preparation of modified organic clay, the mass mixing ratio of sodium-based clay raw material, cetyltrimethylammonium bromide and lanthanum oxide is (2-2.6):1:(0.1-0.3), which can ensure the stable and excellent corresponding effect brought by the combination of modified organic clay and seaweed fiber. Further combined with Examples 20-21 and Table 2, it can be seen that if modified organic clay or seaweed fiber is added and used alone, although it can bring an increase in impact strength and tensile strength, the improvement effect is limited, and the sum of the improvement effects brought by their respective single use is far less excellent than the effect brought by their compounding. Thus, it can be seen that when modified organic clay and seaweed fiber are added and used as functional additives, a significant improvement effect of 1+1>2 can be brought, and then a flexible insulating board with better quality can be obtained.

[0074] This specific embodiment is only an interpretation of the present application, and it is not a limitation of the present application. Those skilled in the art can make modifications without creative contributions to this embodiment according to needs after reading this specification, but as long as it is within the scope of the claims of the present application, it is protected by the patent law.

Claims

1. A flexible insulating board based on a brominated epoxy resin, characterized in that: Made from the following raw materials in parts by weight: 90-100 parts of bromine-containing epoxy resin; 10-15 parts of curing agent; 0.4-1 part of curing accelerator; 20-30 parts of diluent; 20-30 parts of filler; Defoaming agent 0.1-0.5 parts; 4-6 parts of dispersant; The bromine-containing epoxy resin is prepared by the following method: S1, after tetrabromobisphenol A and epichlorohydrin are mixed, a first catalyst is added and stirred to carry out etherification reaction, and then toluene solvent and sodium hydroxide solution are added to carry out reaction, after the reaction is completed, the mixture is allowed to stand and the layers are separated, and the aqueous phase is removed to obtain a bromine-containing epoxy resin polymerization intermediate; S2, mixing the bromine-containing epoxy resin polymer intermediate obtained in step S1 with tetrabromobisphenol A, heating and melting, adding a second catalyst to carry out polymerization reaction, and obtaining an initial bromine-containing epoxy resin product; S3, mixing toluene diisocyanate and polypropylene glycol to obtain a modifier; then mixing the initial product of the bromine-containing epoxy resin obtained in step S2 with the modifier, adding a third catalyst to carry out heating reaction, and obtaining a bromine-containing epoxy resin.

2. The flexible insulating board based on bromine-containing epoxy resin according to claim 1, characterized in that: In step S1, the molar ratio of tetrabromobisphenol A to epichlorohydrin is 1:(0.4-0.5).

3. The flexible insulating board based on bromine-containing epoxy resin according to claim 1, characterized in that: In step S2, the mass mixing ratio of the bromine-containing epoxy resin polymer intermediate and tetrabromobisphenol is (1.1-1.3):

1.

4. The flexible insulating board based on bromine-containing epoxy resin according to claim 1, characterized in that: In step S3, the molar ratio of toluene diisocyanate to polypropylene glycol is (1.8-2.2):

1.

5. The flexible insulation board based on bromine-containing epoxy resin according to claim 1, characterized in that: In step S3, the mass mixing ratio of the initial product of the bromine-containing epoxy resin and the modifier is (2.8-3.2):

1.

6. The flexible insulating board based on bromine-containing epoxy resin according to claim 1, characterized in that: The raw material is also added with 4-8 parts by weight of a functional additive, wherein the functional additive is composed of modified organic clay and seaweed fiber, and the weight ratio of the modified organic clay to the seaweed fiber is 1:(1.4-1.8); The modified organoclay is prepared by the following method: The sodium-based clay raw material is dispersed in deionized water, and hexadecyltrimethylammonium bromide and lanthanum oxide are added after heating. After stirring for reaction, the modified organic clay is obtained by suction filtration, washing and drying.

7. The flexible insulating board based on bromine-containing epoxy resin according to claim 6, characterized in that: The weight ratio of the modified organic clay to the seaweed fiber is 1:1.

6.

8. The flexible insulation board based on bromine-containing epoxy resin according to claim 6, characterized in that: In the preparation of modified organic clay, the mass mixing ratio of sodium-based clay raw material, hexadecyltrimethylammonium bromide and lanthanum oxide is (2-2.6):1:(0.1-0.3).

9. The flexible insulating board based on bromine-containing epoxy resin according to claim 8, characterized in that: The mass mixing ratio of the sodium-based clay raw material, hexadecyltrimethylammonium bromide and lanthanum oxide is 2.3:1:0.

2.

10. The method for preparing a flexible insulating board based on bromine-containing epoxy resin according to claim 1, characterized in that: The following steps are involved: (1) Prepare raw materials including bromine-containing epoxy resin, curing agent, curing accelerator, diluent, filler, defoamer and dispersant according to the proportion; (2) placing the bromine-containing epoxy resin in step (1) in a reaction container, adding a diluent, a filler, a defoamer and a dispersant, and mixing them evenly, and then adding a curing agent and a curing accelerator to obtain a mixture; (3) The mixed material in step (2) is placed into a mold for high temperature curing. After curing, the mixed material is cooled and demolded to obtain a flexible insulating board based on bromine-containing epoxy resin.

Images