Water-based epoxy resin film former for wrapped yarn and its preparation method

Abstract

The present invention belongs to the technical field of sizing agents for glass fibers, and particularly relates to an aqueous epoxy resin sizing agent for winding yarns and a preparation method thereof. The aqueous epoxy resin sizing agent for winding yarns is made from the following raw materials in parts by weight: 100 parts of bisphenol A epoxy resin, 5 - 20 parts of a reactive nonionic emulsifier, and 80 - 100 parts of deionized water; the preparation method of the reactive nonionic emulsifier comprises the following steps: reacting a block polyether with an acid anhydride to obtain a carboxyl-terminated modified block polyether; reacting the carboxyl-terminated modified block polyether, an epoxy resin and a composite catalyst to obtain the reactive nonionic emulsifier. The present invention can improve the performance of glass fiber yarns for winding molding, so as to meet the requirements of good compatibility with the matrix resin of the composite material, good impregnation property and high comprehensive performance of the composite material.

Description

Technical Field

[0001] The present invention belongs to the technical field of glass fiber sizing agents, and particularly relates to an aqueous epoxy resin sizing agent for winding yarns and a preparation method thereof. Background Art

[0002] Fiber winding molding is a fast and efficient method. Its process is to wind continuous fibers (or cloth tapes, prepreg yarns) impregnated with resin sizing onto a mandrel according to certain rules, and then through curing and demolding, a strong and lightweight composite material is obtained. Fiber winding molded products have excellent corrosion resistance, high durability, light weight and high strength, and are convenient for installation and maintenance, and are widely used in fields such as oil transportation, sewage treatment, seawater desalination, aerospace, power transmission, gas and liquid storage, and sports and leisure.

[0003] Glass fibers (winding yarns) used for winding molding have advantages such as high mechanical properties, good chemical resistance, low price, and wide sources compared with other types of fibers, and are widely used in the winding molding process. However, with the continuous improvement and upgrading of the pool kiln drawing technology and the continuous extension and expansion of the application fields of winding molded products, higher requirements are put forward for the performance of winding yarns. And glass fibers themselves have defects such as low strength and brittleness, and their own defects must be compensated by sizing agents to improve their performance; among them, the sizing agent, as a key component in the sizing agent, determines the bundling property, cohesion, softness and hardness of the roving, as well as the speed of wetting and penetration of the roving by the resin. Therefore, the development and research of glass fiber sizing agents, especially sizing agents, are crucial.

[0004] Epoxy resin has outstanding characteristics as a sizing agent. On the one hand, epoxy resin itself has good corrosion resistance, solvent resistance, electrical insulation, etc. The polar hydroxyl groups and ether bonds in its structure have extremely strong adhesion to the surface of glass fibers, so it has better protection function and bundling property for glass fibers. On the other hand, there are many varieties of epoxy resins and high selectivity. Different types and grades of resins can be selected according to different uses, and chemical modification can also be carried out using its active epoxy end groups to prepare different sizing agent resins. Based on this, epoxy resin is a sizing agent resin with wide application and good prospects.

[0005] Chinese Patent CN 104387554 A discloses a preparation method of a polyurethane-modified epoxy resin film-forming agent, which is carried out according to the following steps: (1) Drop the acetone solution of polyethylene glycol into the acetone solution of diisocyanate compounds. After dropping, control the temperature at 54-58 °C and react for 1-2 h to obtain a polyurethane prepolymer for standby; (2) Put epoxy resin into a reactor, after vacuum drying, add solvent PM, acetone III, and catalyst B to obtain an epoxy resin reaction solution. Drop the polyurethane prepolymer into the epoxy resin reaction solution. After dropping, react at 55-60 °C for 1-2 h to obtain a polyurethane-modified epoxy resin; (3) Mix the polyurethane-modified epoxy resin with a self-made emulsifier, and slowly add water under stirring until phase inversion into an emulsion. Continue to add water to adjust the solid content in the emulsion to 35 wt% - 40 wt%. The obtained emulsion is the polyurethane-modified epoxy resin film-forming agent. This patent effectively improves the stiffness and bundling property of glass fibers through the polyurethane-modified epoxy resin film-forming agent. However, the preparation process of the film-forming agent is complex. At the same time, catalysts such as triphenylphosphine and boron trifluoride are used in the preparation process, the reaction temperature is relatively high (needs to be controlled above 100 °C), the reaction is relatively violent, there are many side reactions, and problems such as cross-linking gel of the product are easily caused during the synthesis process. Therefore, the reaction process is not easy to control, the requirements for industrial production conditions are relatively high, and compared with quaternary ammonium salt catalysts, the efficiency of triphenylphosphine and boron trifluoride catalysts in catalyzing the reaction of carboxylic acid and epoxy group is relatively low. In addition, the introduction of organic solvents such as acetone does not meet the development requirements for safety and environmental protection in the industry.

[0006] Chinese Patent CN 105254188 A discloses a special film-forming agent for glass fibers used in wind turbine blades and its preparation method. The components of the water emulsion are as follows by weight percentage: 50.1 - 57.3% bisphenol A epoxy resin (epoxy equivalent 196 - 270); 4.3 - 5.7% emulsifier A: epoxy resin-modified emulsifier; 1.5 - 3.0% emulsifier B: ethylene oxide-propylene oxide block copolymer; 43.5 - 47.5% deionized water; the sum of the weight percentages of the epoxy resin and the emulsifier is not less than 59.5%. Heat the epoxy resin to a flowing state and put it into an emulsifying kettle. Then, successively add 180 g of emulsifier A and 36 g of emulsifier B. Adjust the temperature in the emulsifying kettle to 70 °C, select a stirring speed of 1200 r / min, and start to slowly add water until it turns into an aqueous phase, and then slowly add water to dilute to a solid content of 55%; analyze the performance of the sample and conduct a wire drawing test. The emulsification process adopted in this patent is an intermittent single-kettle production process, and the industrial production efficiency is low.

[0007] When preparing emulsifiers using catalysts such as Lewis acids and proton acids in the prior art, the reaction is relatively violent, the reaction temperature is relatively high, there are many side reactions, and self-polymerization of epoxy resin is easily triggered during the synthesis process, resulting in local gelation, etc. Therefore, the reaction process is not easy to control. In addition, the catalyst residues are likely to continue to trigger the reaction of epoxy resin under high-temperature heating conditions, causing problems such as gelation during application. In addition, catalysts such as Lewis acids or proton acids are highly corrosive and have pungent odors, which are inconvenient to operate and have low safety during use. Summary of the Invention

[0008] The purpose of the present invention is to provide an aqueous epoxy resin film-forming agent for winding yarns, which can improve the performance of glass fiber yarns used for winding molding, so as to meet the requirements of good compatibility with the matrix resin of the composite material, good impregnation property, and high comprehensive performance of the composite material; the present invention also provides a preparation method of the aqueous epoxy resin film-forming agent for winding yarns.

[0009] The aqueous epoxy resin film-forming agent for winding yarns described in the present invention is made from the following raw materials in parts by weight:

[0010] Bisphenol A epoxy resin 100 parts

[0011] Reactive non-ionic emulsifier 5 - 20 parts

[0012] Deionized water 80 - 100 parts;

[0013] The preparation method of the reactive non-ionic emulsifier includes the following steps:

[0014] (1) The block polyether reacts with the acid anhydride to obtain a carboxyl-terminated modified block polyether;

[0015] (2) The carboxyl-terminated modified block polyether, epoxy resin and composite catalyst react to obtain a reactive non-ionic emulsifier.

[0016] The epoxy equivalent of the bisphenol A epoxy resin described is 180 - 280 g / eq.

[0017] The block polyether described in step (1) is a block polymer of polyoxyethylene and polyoxypropylene, with a molecular weight of 3000 - 10000 g / mol.

[0018] The acid anhydride described in step (1) is one or more of hexahydrophthalic anhydride, tetrahydrophthalic anhydride, succinic anhydride, phthalic anhydride, maleic anhydride or trimellitic anhydride.

[0019] The molar ratio of the block polyether to the acid anhydride described in step (1) is 1:1 - 2.

[0020] The reaction temperature described in step (1) is 80 - 130 °C, and the reaction time is 1 - 6 h.

[0021] The epoxy resin described in step (2) is one or more of E44, E42 or E51.

[0022] The molar ratio of the epoxy groups in the epoxy resin described in step (2) to the carboxyl groups in the carboxyl-terminated modified block polyether is 1.1 - 2:1.

[0023] The composite catalyst described in step (2) is a mixture of a quaternary ammonium salt catalyst and a double metal cyanide complex catalyst.

[0024] The quaternary ammonium salt catalyst is one or more of tetraethylammonium bromide, tetrabutylammonium bromide, tetramethylammonium bromide, tetramethylammonium chloride, tetraethylammonium chloride or benzyltriethylammonium bromide.

[0025] The double metal cyanide complex catalyst is one or two of Co-Zn double metal cyanide complex catalyst or Fe-Zn double metal cyanide complex catalyst.

[0026] The mass ratio of the quaternary ammonium salt catalyst to the double metal cyanide complex catalyst is 1 - 9:3.

[0027] The dosage of the composite catalyst described in step (2) is 0.05 - 1% of the total mass of the carboxyl-terminated modified block polyether and the epoxy resin.

[0028] The reaction temperature described in step (2) is 65 - 90 °C, and the reaction time is 1 - 3 h.

[0029] The preparation method of the reactive non-ionic emulsifier includes the following specific steps:

[0030] (1) Heat the block polyether until it is completely melted, evacuate to remove the moisture in the block polyether, then add the anhydride to the block polyether, and heat and stir to react to the theoretical acid value to obtain the carboxyl-terminated modified block polyether.

[0031] (2) Add the epoxy resin to the carboxyl-terminated modified block polyether, heat and stir until it is completely melted to obtain a mixed material; add the composite catalyst to the mixed material, and carry out a constant temperature reaction under the protection of an inert gas. When the acid value of the reaction product is measured to decrease to 0, pour out and cool to obtain the reactive non-ionic emulsifier.

[0032] The melting temperature described in step (1) is 110 - 130 °C, the evacuation time is 0.5 - 3 h, and the evacuation time starts to be calculated when the vacuum degree reaches -100 kPa to ensure more thorough water removal.

[0033] The preparation method of the waterborne epoxy resin film-forming agent for winding yarn of the present invention is to preheat bisphenol A epoxy resin and a reactive nonionic emulsifier first, then stir and mix them, and then add part of deionized water and stir and mix to obtain a mixed solution; after the mixed solution is emulsified by high-speed dispersion, the remaining deionized water is added for dilution to obtain the waterborne epoxy resin film-forming agent for winding yarn.

[0034] The preheating is carried out alternately using two preheating tanks.

[0035] The preheating temperature is 80-120 °C.

[0036] The high-speed dispersion emulsification rate is 500-10000 rpm.

[0037] The high-speed dispersion emulsification temperature is 25-50 °C, preferably 40-45 °C.

[0038] The dosage of the part of deionized water is 10-20 parts.

[0039] The production device used in the preparation method of the waterborne epoxy resin film-forming agent for winding yarn of the present invention includes a pipeline high-shear emulsifier, which is respectively connected to a first preheating tank and a second preheating tank, and is respectively connected to a first dilution tank and a second dilution tank. A sampling port is arranged on the outlet pipeline of the pipeline high-shear emulsifier. The first dilution tank and the second dilution tank are respectively connected to a filter, and the filter is connected to a product barrel. The first preheating tank is connected to a first heat-conducting oil mold temperature controller, and the second preheating tank is connected to a second heat-conducting oil mold temperature controller.

[0040] The preparation method of the waterborne epoxy resin film-forming agent for winding yarn of the present invention includes the following steps:

[0041] (1) First, preheat bisphenol A epoxy resin and a reactive nonionic emulsifier in the first preheating tank until the above materials are in a liquid state and stir and mix evenly; then add metered phase-transfer deionized water to the above first preheating tank, stir and mix evenly, cool down to the set emulsification process temperature, keep warm, and wait for emulsification to obtain a mixed solution.

[0042] (2) Pump the mixture in the first preheating tank into the emulsification chamber of the in-line high-shear emulsifier. After high-speed dispersion and emulsification, and after being detected as aqueous by the conductivity meter at the phase inversion point at the outlet of the emulsifier (after turning into the aqueous phase, the value of the conductivity meter will change suddenly, that is, it changes from a conductivity of 0 to the conductivity of deionized water, indicating a phase transition, and the outlet is in the aqueous state), it enters the first dilution tank or the second dilution tank, and the remaining deionized water is added to adjust the solid content to 50-60%, obtaining an aqueous epoxy resin film-forming agent for winding yarn. If no phase transition occurs, it is pumped into the first preheating tank through the outlet bypass pipeline of the in-line high-shear emulsifier, and the above emulsification process is repeated until emulsification is completed.

[0043] (3) The second preheating tank simultaneously undergoes the above preheating process to obtain a mixture. After the emulsification in the first preheating tank is completed, it can be switched to the second preheating tank through the pipeline to carry out the above emulsification process. In this way, the first preheating tank and the second preheating tank alternate, and the continuous production and preparation of the aqueous epoxy resin film-forming agent for winding yarn can be realized.

[0044] The present invention synthesizes a reactive nonionic aqueous epoxy resin emulsifier. This emulsifier uses the epoxy resin main chain as the hydrophobic part, and hydrophilic segments are introduced into the main chain as the hydrophilic part, making it have good hydrophilicity, and having strong compatibility and interaction force with the resin. Therefore, this emulsifier has good emulsification effect and strong ability to control particle size. In addition, this emulsifier has reactive groups, and when coated on the surface of the winding yarn, it can participate in the curing reaction of the polymer matrix, avoiding the influence of emulsifier migration on the comprehensive performance of the composite material.

[0045] Aiming at the problems in the current industry such as the complex preparation process of epoxy film-forming agents, the unstable reaction caused by using catalysts such as Lewis acids and proton acids, and the low industrial production efficiency caused by the batch preparation process, in the present invention, a binary composite catalyst composed of a quaternary ammonium salt and a double metal cyanide complex (DMCC) is used to prepare the emulsifier, which can effectively reduce the reaction temperature, the reaction conditions are mild and controllable, the reaction efficiency is high, there are fewer side reactions, and no volatile irritating gases are generated. The present invention uses a continuous emulsification process to prepare the emulsion, which has high efficiency, small emulsion particle size and high stability, has broad application prospects, and is more convenient for industrial production.

[0046] In the present invention, a binary composite catalyst composed of a quaternary ammonium salt and a double metal cyanide complex (DMCC) is adopted. There is a synergistic catalytic effect between the DMCC and the quaternary ammonium salt, which is beneficial to increasing the conversion rate of epoxy groups in epoxy resin. The synergistic catalytic mechanism of the two is as follows: First, the oxygen atom on the epoxy group coordinates with the metal active center in the DMCC catalyst, promoting the activation of the epoxy group. Then, the bromine or chlorine anion in the quaternary ammonium salt acts as an effective nucleophile and is more likely to attack the carbon atom with less steric hindrance on the epoxy group, promoting the ring-opening of the epoxy group, which is more conducive to the subsequent reaction and improves the reaction efficiency. In addition, the synergistic effect of this binary composite catalysis can also reduce the activation energy of the reaction, thereby effectively reducing the reaction temperature and enabling the ring-opening reaction of the epoxy group to proceed at a lower temperature.

[0047] The beneficial effects of the present invention are as follows:

[0048] (1) The present invention synthesizes a reactive non-ionic waterborne epoxy emulsifier by using a binary composite catalyst composed of a quaternary ammonium salt and a double metal cyanide complex (DMCC), avoiding problems such as violent reactions, difficult process control, gelation in subsequent applications caused by residues, and low operation safety and convenience caused by high corrosivity and pungent odor of catalysts in the prior art. The reaction conditions for preparing this emulsifier are mild and controllable, with high reaction efficiency and fewer side reactions. There are no corrosive substances and no volatile pungent gases are generated, so the operation safety is high, meeting the requirements of subsequent industrial production.

[0049] (2) Compared with the traditional batch production process, the preparation process of the present invention can realize the continuous industrial production of the waterborne epoxy emulsion film-forming agent, improving the industrial production efficiency and output and reducing the product cost.

[0050] (3) The waterborne epoxy resin film-forming agent prepared by the present invention has small particle size and narrow particle size distribution, and the film-forming agent has good performance and is stable and controllable.

[0051] (4) The waterborne epoxy resin film-forming agent prepared by the present invention has good application performance. When used in the preparation of composites by winding yarn molding, the performance of the composites is greatly improved. Description of the Drawings

[0052] Figure 1 is a schematic structural diagram of the production device of the waterborne epoxy resin film-forming agent for winding yarn of the present invention;

[0053] In the figure: 1. Pipeline high-shear emulsifier; 2. First preheating tank; 3. Second preheating tank; 4. First dilution tank; 5. Second dilution tank; 6. Sampling port; 7. Filter; 8. Product barrel; 9. First heat transfer oil mold temperature controller; 10. Second heat transfer oil mold temperature controller. Detailed Embodiments

[0054] The present invention will be further described below in conjunction with embodiments.

[0055] Example 1

[0056] 14 kg of Pluronic F68 was added to a reaction kettle equipped with a thermometer, a condenser and a stirrer. Nitrogen was introduced for protection and heated to 120 °C to completely melt it, obtaining a molten liquid. The above molten liquid was evacuated for 3 h using a vacuum suction device to remove the moisture in the material. 0.26 kg of hexahydrophthalic anhydride was added to the above molten liquid, and the reaction was carried out at 90 °C for 5 h to the theoretical acid value, obtaining a carboxyl-terminated modified block polyether. Keeping the above constant temperature, 0.15 kg of epoxy resin E51 was added to the carboxyl-terminated modified block polyether. After it was completely melted and stirred evenly, 13.52 g of a composite catalyst (wherein the mass ratio of tetrabutylammonium bromide to Co-Zn double metal cyanide complex was 3:1) was added and the reaction was carried out at a constant temperature for 1.5 h until the acid value was 0. Then it was poured out and cooled to obtain a reactive nonionic emulsifier.

[0057] As Figure 1 shown, the production device of the water-based epoxy resin film-forming agent for winding yarn includes a pipeline high-shear emulsifier, which is respectively connected to a first preheating tank and a second preheating tank, and is respectively connected to a first dilution tank and a second dilution tank. A sampling port is arranged on the outlet pipeline of the pipeline high-shear emulsifier. The first dilution tank and the second dilution tank are respectively connected to a filter, and the filter is connected to a product barrel. The first preheating tank is connected to a first heat-conducting oil mold temperature controller, and the second preheating tank is connected to a second heat-conducting oil mold temperature controller.

[0058] 100 kg of bisphenol A epoxy resin (epoxy equivalent 245 g / eq) and 11 kg of reactive nonionic emulsifier were weighed in each of the first preheating tank and the second preheating tank, and the temperature was raised to 100 °C until completely melted and stirred and mixed evenly. 15 kg of deionized water was respectively weighed and added to the above first preheating tank and second preheating tank, stirred evenly, and cooled to 45 °C for heat preservation for emulsification, obtaining a mixed liquid. The mixed liquid in the first preheating tank was pumped into the emulsification cavity of the pipeline high-shear emulsifier (100 kg / h), and the high-speed dispersion emulsification rate was set at 1500 rpm for high-speed dispersion emulsification. The conductivity at the outlet was measured to be 18 μs / cm, indicating that the material after phase inversion was in a water-based state. The material after phase inversion was directly pumped into the first dilution tank, and the remaining deionized water was added to adjust the solid content, obtaining a milky white water-based epoxy resin film-forming agent for winding yarn with a solid content of 55%. After the emulsification of the material in the first preheating tank was completed, the pipeline was switched to the second preheating tank to repeat the above emulsification process. The first preheating tank and the second preheating tank were alternately used for production.

[0059] Example 2

[0060] Add 14 kg of Pluronic F77 into a reaction kettle equipped with a thermometer, a condenser and a stirrer. Pass nitrogen for protection and heat it to 120 °C until it is completely melted to obtain a molten liquid. Use a vacuum suction device to vacuum the above molten liquid for 3 h to remove the moisture in the material. Add 0.31 kg of maleic anhydride into the above molten liquid and react at 130 °C for 2 h to the theoretical acid value to obtain a carboxyl-terminated modified block polyether. Cool down to 70 °C, add 0.51 kg of epoxy resin E42 into the above carboxyl-terminated modified block polyether. Wait until it is completely melted and stirred evenly, add 8.6 g of a composite catalyst (wherein the mass ratio of tetraethylammonium bromide to Fe-Zn double metal cyanide complex is 1:1), and react at a constant temperature for 3 h until the acid value is 0. Pour out and cool to obtain a reactive nonionic emulsifier.

[0061] The production device of the water-based epoxy resin film-forming agent for winding yarn is the same as that in Example 1.

[0062] Weigh 100 kg of bisphenol A epoxy resin (epoxy equivalent 245 g / eq) and 20 kg of reactive nonionic emulsifier in the first preheating tank and the second preheating tank respectively, and heat up to 100 °C until it is completely melted and stirred and mixed evenly. Weigh 13 kg of deionized water and add it into the above first preheating tank and the second preheating tank respectively, stir evenly, and cool down to 42 °C for heat preservation waiting for emulsification to obtain a mixed liquid. Pump the mixed liquid in the first preheating tank into the emulsification chamber of a pipeline high-shear emulsifier (100 kg / h), set the high-speed dispersion emulsification rate to 2000 rpm for high-speed dispersion emulsification, and measure that the conductivity at the outlet is 16 us / cm, which indicates that the material after phase inversion is in a water-based state. The material after phase inversion is directly pumped into the first dilution tank, and the remaining deionized water is added to adjust the solid content to obtain a milky white water-based epoxy resin film-forming agent for winding yarn with a solid content of 55%. After the emulsification of the material in the first preheating tank is completed, switch the pipeline to the second preheating tank and repeat the above emulsification process. The first preheating tank and the second preheating tank are alternately used for production.

[0063] Example 3

[0064] Add 14 kg of Pluronic F108 to a reactor equipped with a thermometer, a condenser, and a stirrer. Protect it by passing nitrogen and heat it to 120 °C to completely melt it, obtaining a molten liquid. Use a vacuum suction device to evacuate the above molten liquid for 3 h to remove the moisture in the material. Add 0.19 kg of succinic anhydride to the above molten liquid and react at 110 °C for 3 h to reach the theoretical acid value, obtaining a carboxyl-terminated modified block polyether. Cool down to 80 °C, add 0.34 kg of epoxy resin E42 to the above carboxyl-terminated modified block polyether. Wait for it to completely melt and stir evenly, add 12.6 g of a composite catalyst (where the mass ratio of tetraethylammonium bromide to Fe-Zn double metal cyanide complex is 3:1), and react at a constant temperature for 2 h until the acid value reaches 0. Pour out and cool to obtain a reactive nonionic emulsifier.

[0065] The production device of the waterborne epoxy resin film-forming agent for winding yarn is the same as that in Example 1.

[0066] Weigh 100 kg of bisphenol A epoxy resin (epoxy equivalent 245 g / eq) and 8 kg of reactive nonionic emulsifier in the first preheating tank and the second preheating tank respectively, and heat up to 100 °C until completely melted and stir to mix evenly. Weigh 20 kg of deionized water and add it to the above first preheating tank and the second preheating tank respectively, stir evenly, and cool down to 42 °C for heat preservation and waiting for emulsification to obtain a mixed liquid. Pump the mixed liquid in the above first preheating tank into the emulsification chamber of a pipeline high-shear emulsifier (100 kg / h), set the high-speed dispersion emulsification rate to 2000 rpm for high-speed dispersion emulsification, and measure the conductivity at the outlet to be 16 us / cm, which indicates that the material after phase inversion is in a waterborne state. The material after phase inversion is directly pumped into the first dilution tank, and the remaining deionized water is added to adjust the solid content to obtain a milky white waterborne epoxy resin film-forming agent for winding yarn with a solid content of 55%. After the emulsification of the material in the first preheating tank is completed, switch the pipeline to the second preheating tank and repeat the above emulsification process. The first preheating tank and the second preheating tank alternate in production.

[0067] The product performance indexes of the waterborne epoxy resin film-forming agent in Example 1 and the same type of film-forming agent are shown in Table 1.

[0068] Table 1 Product performance indexes of the waterborne epoxy resin film-forming agent in Example 1 and the same type of film-forming agent

[0069]

[0070] Dilution stability: Dilute the film-forming agent to a solid content of 10%, pour it into a corresponding stoppered graduated cylinder, and store it statically at room temperature for 7 d (storage conditions: 25 °C, 7 d), and observe whether the emulsion layers and precipitates.

[0071] Centrifugal stability: Pour the film-forming agent into a centrifuge tube and place it at the corresponding position of the centrifuge for the centrifugal stability experiment (rotation speed 4000 rpm, time 30 min). Observe and record the state changes of the above samples after centrifugation.

[0072] It can be seen from the centrifugal stability in Table 1 that the film-forming agent of Example 1 has good stability; from the dilution stability, it can be seen that the supernatant of the film-forming agent of Example 1 is less and its use stability is good.

[0073] The performance test indexes of the composite materials prepared with the film-forming agent of Example 1 and the same type of film-forming agent 1 are shown in Table 2.

[0074] Table 2 Performance test indexes of the composite materials prepared with the film-forming agent of Example 1 and the same type of film-forming agent 1

[0075]

[0076] It can be seen from Table 2 that the comprehensive performance of the composite material prepared with the film-forming agent of Example 1 is significantly better than that of the composite material prepared with the same type of film-forming agent 1.

Claims

1. An aqueous epoxy resin film-forming agent for wrapped yarn, characterized in that it is made from the following raw materials in parts by weight: Bisphenol A epoxy resin 100 parts Reactive non-ionic emulsifier 5 - 20 parts Deionized water 80 - 100 parts; The preparation method of the reactive non-ionic emulsifier includes the following steps: (1) Block polyether reacts with acid anhydride to obtain carboxyl-terminated modified block polyether; (2) The carboxyl-terminated modified block polyether, epoxy resin and composite catalyst react to obtain a reactive non-ionic emulsifier; The composite catalyst described in step (2) is a mixture of quaternary ammonium salt catalyst and double metal cyanide complex catalyst.

2. The aqueous epoxy resin film-forming agent for wrapped yarn according to claim 1, characterized in that the epoxy equivalent of the bisphenol A epoxy resin is 180 - 280 g / eq.

3. The aqueous epoxy resin film-forming agent for wrapped yarn according to claim 1, characterized in that the block polyether described in step (1) is a block polymer of polyoxyethylene and polyoxypropylene, with a molecular weight of 3000 - 10000 g / mol; the acid anhydride is one or more of hexahydrophthalic anhydride, tetrahydrophthalic anhydride, succinic anhydride, phthalic anhydride, maleic anhydride or trimellitic anhydride; the molar ratio of block polyether to acid anhydride is 1:1 - 2; the reaction temperature is 80 - 130 °C, and the reaction time is 1 - 6 h.

4. The aqueous epoxy resin film-forming agent for wrapped yarn according to claim 1, characterized in that the epoxy resin described in step (2) is one or more of E44, E42 or E51, and the molar ratio of the epoxy group in the epoxy resin to the carboxyl group at the end of the carboxyl-terminated modified block polyether is 1.1 - 2:

1.

5. The aqueous epoxy resin film-forming agent for wrapped yarn according to claim 1, characterized in that the quaternary ammonium salt catalyst is one or more of tetraethylammonium bromide, tetrabutylammonium bromide, tetramethylammonium bromide, tetramethylammonium chloride, tetraethylammonium chloride or benzyltriethylammonium bromide, and the double metal cyanide complex catalyst is one or two of Co-Zn double metal cyanide complex catalyst or Fe-Zn double metal cyanide complex catalyst, and the mass ratio of the quaternary ammonium salt catalyst to the double metal cyanide complex catalyst is 1 - 9:

3.

6. The aqueous epoxy resin film-forming agent for wrapped yarn according to claim 1, characterized in that the dosage of the composite catalyst described in step (2) is 0.05 - 1% of the total mass of the carboxyl-terminated modified block polyether and the epoxy resin.

7. The aqueous epoxy resin film-forming agent for wrapped yarn according to claim 1, characterized in that the reaction temperature described in step (2) is 65 - 90 °C, and the reaction time is 1 - 3 h.

8. A preparation method of the aqueous epoxy resin film-forming agent for wrapped yarn according to any one of claims 1 - 7, characterized in that first preheat and stir and mix bisphenol A epoxy resin and reactive non-ionic emulsifier, then add part of deionized water and stir and mix to obtain a mixed solution; after the mixed solution is dispersed and emulsified at high speed, add the remaining deionized water for dilution to obtain the aqueous epoxy resin film-forming agent for wrapped yarn.

9. The preparation method of the aqueous epoxy resin film-forming agent for wrapped yarn according to claim 8, characterized in that The preheating is carried out by alternately using two preheating tanks. The preheating temperature is 80 - 120 °C, the high-speed dispersion and emulsification rate is 500 - 10,000 rpm, the high-speed dispersion and emulsification temperature is 25 - 50 °C, and the dosage of partial deionized water is 10 - 20 parts.

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