Corrosion-resistant epoxy resin composite carbon fiber sizing agent and preparation method thereof

Abstract

The invention discloses a corrosion-resistant epoxy resin composite carbon fiber sizing agent and a preparation method thereof, and belongs to the technical field of preparation of carbon fiber sizing agents. The corrosion-resistant epoxy resin composite carbon fiber sizing agent is prepared by blending amine-terminated polyether modified epoxy resin emulsion with different double bond contents and modified nano silicon dioxide, the mass ratio of the amino-terminated polyether modified epoxy resin emulsion with different double bond contents to the modified nano silicon dioxide is (5-10): (5-10). The sizing agent is uniform in particle size distribution and good in stability, can greatly improve the problem that the corrosion resistance of carbon fibers and the bonding force of a carbon fiber interface are reduced, effectively improves the corrosion resistance and the surface roughness of the carbon fibers, and enhances the performance of a carbon fiber composite material; the carbon fiber composite material has certain application value for expanding the application field and widening the application conditions of the carbon fiber composite material.

Description

Technical Field

[0001] The invention belongs to the technical field of carbon fiber sizing agent preparation, and more particularly relates to a corrosion-resistant epoxy resin composite carbon fiber sizing agent and a preparation method thereof. Background Art

[0002] Carbon fiber is a special inorganic fiber with advantages such as high specific strength, high specific modulus, and corrosion resistance. It is an excellent reinforcement material for composite materials. However, the surface of carbon fiber is inert and its compatibility with resin is poor. In addition, due to its brittleness, carbon fiber is prone to fuzzing and breaking during the production process, which greatly affects the mechanical properties of carbon fiber composites. In order to improve the quality of carbon fiber and the interface performance of composite materials, sizing the carbon fiber is particularly important. However, existing EP coatings have a highly cross-linked structure and gaps between molecules. This leads to the disadvantages of epoxy resin coatings such as high spatial structural porosity and poor corrosion diffusion resistance. At the same time, the surface of most epoxy coatings contains a large number of hydrophilic functional groups. These groups accelerate the penetration of corrosive media into the epoxy coating, allowing the corrosive media to reach the surface of the carbon fiber, resulting in a weak protective effect on the substrate. In recent years, relevant studies have shown that the corrosion resistance of EP can be improved by adding nanoparticles such as silica, boron nitride, graphene, carbon nanotubes, clay minerals and polymer particles.

[0003] Carbon fiber reinforced polymer composites (CFRP) have been widely used in aerospace, automotive, energy equipment and smart devices. However, poor interfacial properties are a key issue for CFRP. Poor interfacial properties may result in insufficient stress transfer at the interface of the composite material, leading to premature failure and inability to fully utilize its performance. The evaporation of water during the film formation process of water-based epoxy film-forming forms water-permeable channels, which makes its corrosion resistance unsatisfactory and limits its widespread application as a carbon fiber coating. Therefore, it is very necessary to develop water-based epoxy sizing agents with high ductility, high toughness and high corrosion resistance. In addition, if the water-based epoxy emulsion has poor compatibility with the anti-corrosion filler, it may lead to a decrease in the adhesion and bonding force between the anti-corrosion coating and the substrate, thereby affecting the protective effect of the coating. Therefore, it is of great significance to strive to effectively enhance the corrosion resistance of water-based epoxy sizing agents. Improving the wettability of the carbon fiber (CF) surface and increasing its surface roughness can both enhance the chemical bond and mechanical interlocking force between the fiber and the host matrix to achieve strong interfacial properties. In recent years, nanoparticles have played a role in high surface roughness and mechanical interlocking at the interface, becoming a research hotspot for interface enhancement. Compared with traditional nanomaterials, nanopolymers (NPs) have advantages such as structural controllability, universal design, and good compatibility. Therefore, how to optimize the sizing agent structure to increase the reactive groups with the matrix resin, improve the performance of the sizing agent between the fiber / resin, and improve the overall performance of the composite material through a simple sizing process has become an urgent problem to be solved in high-performance carbon fiber composites. Summary of the Invention

[0004] The purpose of the present invention is to provide a corrosion-resistant epoxy resin composite carbon fiber sizing agent and a preparation method thereof to solve the problems existing in the above-mentioned prior art. The sizing agent prepared by this method has uniform particle size distribution and good stability, can greatly improve the corrosion resistance of carbon fiber and the problem of decreased interfacial adhesion of carbon fiber, effectively improve the corrosion resistance and surface roughness of carbon fiber, enhance the performance of carbon fiber composite materials, and have certain application value for expanding the application field of carbon fiber composite materials and broadening the application conditions.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] One of the technical solutions of the present invention is to provide a corrosion-resistant epoxy resin composite carbon fiber sizing agent, wherein the corrosion-resistant epoxy resin composite carbon fiber sizing agent is formed by blending an amino-terminated polyether modified epoxy resin emulsion with different double bond contents and modified nano-silica;

[0007] The mass ratio of the amino-terminated polyether modified epoxy resin emulsion with different double bond contents to the modified nano-silica is 5-10:5-10;

[0008] The amino-terminated polyether-modified epoxy resin emulsion with different double bond contents comprises, by weight, 30 to 60 parts of epoxy resin, 50 to 100 parts of amino-terminated polyether, 80 to 200 parts of aliphatic primary amine, 50 to 100 parts of isocyanate, 80 to 100 parts of enol ether, 10 to 30 parts of cosolvent, 10 to 20 parts of reaction solvent and 300 to 500 parts of water.

[0009] Preferably, the particle size of the modified nano-silica is 20 to 50 nm;

[0010] The preparation steps of the modified nano-silica include: mixing nano-silica, a silane coupling agent and a mixed solvent and reacting the mixture to obtain the modified nano-silica.

[0011] Preferably, the mass ratio of the nano-silica, silane coupling agent and mixed solvent is 6-10:3-4:10-15; the silane coupling agent includes one or more of KH550, KH570 and KH-560; the mixed solvent is water and ethanol; the reaction temperature is 80-100° C., and the reaction time is 2-3 hours.

[0012] Preferably, the steps for preparing the amino-terminated polyether-modified epoxy resin emulsion having different double bond contents include:

[0013] According to the prescribed amount, the amino-terminated polyether, the aliphatic primary amine and the cosolvent are heated and mixed to obtain a primary amine mixed solution; the epoxy resin is first dissolved in the reaction solvent to obtain a mixed solution, and the mixed solution is then dropwise added to the primary amine mixed solution and reacted to obtain an amino-modified epoxy resin;

[0014] Mixing isocyanate and enol ether in the prescribed amounts and subjecting them to a first heating reaction to obtain an unsaturated double bond intermediate;

[0015] According to the prescribed amount, the amino-modified epoxy resin and the unsaturated double bond intermediate are mixed and subjected to a second heating reaction to obtain a water-based epoxy resin, and water is added thereto to obtain the amino-terminated polyether-modified epoxy resin emulsion with different double bond contents.

[0016] Preferably, the aliphatic primary amine includes one or more of dodecylamine, tetradecylamine, hexadecylamine and octadecylamine; the cosolvent is a mixture of alcohol ether and n-butanol; the alcohol ether includes propylene glycol methyl ether or ethylene glycol methyl ether; the heating and mixing temperature is 80-95° C., and the time is 45-60 minutes.

[0017] Preferably, the epoxy resin includes one or more of solid epoxy resin, low viscosity epoxy resin E51 and hydrogenated epoxy resin; the reaction solvent includes one or more of propylene glycol methyl ether, ethylene glycol methyl ether and tetrahydrofuran; the reaction temperature is 110-120°C, the stirring speed is 300-500 r / min, and the time is 2-4h.

[0018] Preferably, the isocyanate includes one or more of toluene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate and diphenylmethane diisocyanate; the temperature of the first heating reaction is 60-70° C., and the time is 2-3 hours.

[0019] Preferably, the temperature of the second heating reaction is 70-90° C., and the time is 2-3 hours; and the solid content of the amino-terminated polyether-modified epoxy resin emulsion with different double bond contents is 30-50%.

[0020] The second technical solution of the present invention is to provide a method for preparing the corrosion-resistant epoxy resin composite carbon fiber sizing agent, comprising the following steps:

[0021] The amino-terminated polyether modified epoxy resin emulsion with different double bond contents and modified nano-silicon dioxide are mixed and reacted to obtain the corrosion-resistant epoxy resin composite carbon fiber sizing agent.

[0022] Preferably, the reaction temperature is 50-60° C. and the reaction time is 2-3 h.

[0023] The present invention discloses the following technical effects:

[0024] The present invention provides a method for preparing water-based epoxy emulsion carbon fiber. The sizing agent prepared by the method has uniform particle size distribution and good stability, can greatly improve the problems of corrosion resistance of carbon fiber and decreased adhesion of carbon fiber interface, effectively improves the corrosion resistance and surface roughness of carbon fiber, enhances the performance of carbon fiber composite materials, and has certain application value for expanding the application field of carbon fiber composite materials and broadening the application conditions. DETAILED DESCRIPTION

[0025] The present invention provides a corrosion-resistant epoxy resin composite carbon fiber sizing agent, which is prepared by blending amino-terminated polyether modified epoxy resin emulsion with different double bond contents and modified nano-silicon dioxide;

[0026] The mass ratio of the amino-terminated polyether modified epoxy resin emulsion with different double bond contents to the modified nano-silica is 5-10:5-10;

[0027] The amino-terminated polyether-modified epoxy resin emulsion with different double bond contents comprises, by weight, 30 to 60 parts of epoxy resin, 50 to 100 parts of amino-terminated polyether, 80 to 200 parts of aliphatic primary amine, 50 to 100 parts of isocyanate, 80 to 100 parts of enol ether, 10 to 30 parts of cosolvent, 10 to 20 parts of reaction solvent and 300 to 500 parts of water.

[0028] In the present invention, the amount of the epoxy resin is preferably 40 to 50 parts, more preferably 45 to 48 parts; the amount of the amino-terminated polyether is preferably 60 to 80 parts, more preferably 70 to 75 parts; the amount of the aliphatic primary amine is preferably 120 to 160 parts, more preferably 130 to 150 parts; the amount of the isocyanate is preferably 60 to 80 parts, more preferably 65 to 70 parts; the amount of the enol ether is preferably 85 to 95 parts, more preferably 80 to 92 parts; the amount of the cosolvent is preferably 15 to 20 parts; the amount of the reaction solvent is preferably 15 parts; the amount of water is preferably 400 to 450 parts, more preferably 420 to 440 parts.

[0029] In the present invention, the particle size of the modified nano-silica is preferably 20 to 50 nm, more preferably 30 to 40 nm.

[0030] In the present invention, the preparation step of the modified nano-silica comprises: mixing nano-silica, a silane coupling agent and a mixed solvent and reacting the mixture to obtain the modified nano-silica.

[0031] In the present invention, the mass ratio of the nano-silica, the silane coupling agent and the mixed solvent is preferably 6-10:3-4:10-15, more preferably 8:3.5:12-14; the silane coupling agent includes one or more of KH550, KH570 and KH-560; the mixed solvent is water and ethanol; the reaction temperature is preferably 80-100°C, more preferably 90-95°C; the reaction time is preferably 2-3h, more preferably 2.5h.

[0032] In the present invention, the steps for preparing the amino-terminated polyether-modified epoxy resin emulsion having different double bond contents include:

[0033] According to the prescribed amount, the amino-terminated polyether, the aliphatic primary amine and the cosolvent are heated and mixed to obtain a primary amine mixed solution; the epoxy resin is first dissolved in the reaction solvent to obtain a mixed solution, and the mixed solution is then dropwise added to the primary amine mixed solution and reacted to obtain an amino-modified epoxy resin;

[0034] Mixing isocyanate and enol ether in the prescribed amounts and subjecting them to a first heating reaction to obtain an unsaturated double bond intermediate;

[0035] According to the prescribed amount, the amino-modified epoxy resin and the unsaturated double bond intermediate are mixed and subjected to a second heating reaction to obtain a water-based epoxy resin, and water is added thereto to obtain the amino-terminated polyether-modified epoxy resin emulsion with different double bond contents.

[0036] In the present invention, the aliphatic primary amine includes one or more of dodecylamine, tetradecylamine, hexadecylamine and octadecylamine; the cosolvent is a mixture of alcohol ether and n-butanol; the alcohol ether includes propylene glycol methyl ether or ethylene glycol methyl ether; the temperature of the heating and mixing is preferably 80-95°C, more preferably 85-90°C; the time is preferably 45-60 min, more preferably 50-55 min.

[0037] In the present invention, the epoxy resin includes one or more of a solid epoxy resin, a low-viscosity epoxy resin E51 and a hydrogenated epoxy resin; the reaction solvent includes one or more of propylene glycol methyl ether, ethylene glycol methyl ether and tetrahydrofuran; the reaction temperature is preferably 110 to 120°C, more preferably 115°C; the stirring speed is preferably 300 to 500 r / min, more preferably 400 r / min; the reaction time is preferably 2 to 4 hours, more preferably 3 hours.

[0038] In the present invention, the isocyanate includes one or more of toluene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate and diphenylmethane diisocyanate; the temperature of the first heating reaction is preferably 60-70°C, more preferably 65°C; the time is preferably 2-3h, more preferably 2.5h.

[0039] In the present invention, the temperature of the second heating reaction is preferably 70-90°C, more preferably 75-80°C; the time is preferably 2-3 hours, more preferably 2.5 hours; the solid content of the amino-terminated polyether modified epoxy resin emulsion with different double bond contents is 30-50%.

[0040] The present invention also provides a method for preparing the corrosion-resistant epoxy resin composite carbon fiber sizing agent, comprising the following steps:

[0041] The amino-terminated polyether modified epoxy resin emulsion with different double bond contents and modified nano-silicon dioxide are mixed and reacted to obtain the corrosion-resistant epoxy resin composite carbon fiber sizing agent.

[0042] In the present invention, the reaction temperature is preferably 50-60° C., more preferably 55° C.; the reaction time is preferably 2-3 h, more preferably 2.5 h.

[0043] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0044] It should be understood that the terms described herein are intended only to describe particular embodiments and are not intended to limit the present invention. In addition, for numerical ranges herein, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. The intermediate value within any stated value or stated range, and each smaller range between any other stated value or intermediate value within the stated range, is also encompassed within the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded within the scope.

[0045] Unless otherwise indicated, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein may also be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of any conflict with any incorporated document, the contents of this specification shall prevail.

[0046] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments described herein without departing from the scope or spirit of the invention. Other embodiments will be apparent to those skilled in the art from the description of the invention. The description and examples are intended to be illustrative only.

[0047] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0048] It should be pointed out that the matters not described in detail in the present invention are conventional operating means in this field and are not the focus of the present invention.

[0049] Unless otherwise specified, the raw materials used in the following examples of the present invention are all commercially available products, and the sources of the commercially available products do not affect the technical effects of the present invention.

[0050] Unless otherwise specified, the normal temperature involved in the present invention is 25±5°C.

[0051] Example 1

[0052] Step 1: Preparation of amino-terminated polyether modified epoxy resin emulsions with different double bond contents:

[0053] 50 parts by mass of amino-terminated polyether and 80 parts by mass of dodecylamine were dissolved in a mixed solution of 10 parts by mass of propylene glycol methyl ether and n-butanol (the volume ratio of propylene glycol methyl ether to n-butanol was 4:1), and the mixture was heated to 80° C. with stirring and kept warm for 45 minutes to obtain a primary amine mixed solution; 30 parts by mass of epoxy resin was dissolved in 10 parts by mass of propylene glycol methyl ether, and stirred at room temperature for 10 minutes to mix them uniformly; and then the mixture was added dropwise to the primary amine mixed solution. After the addition was complete, the temperature was slowly raised to 110° C., the stirring speed was 380 r / min, and the reaction time was 3 hours to obtain an amino-modified epoxy resin;

[0054] Add 50 parts by mass of isophorone diisocyanate to 80 parts by mass of pentaerythritol triallyl ether, stir and heat to 60°C for 2 hours to obtain an unsaturated double bond intermediate;

[0055] 100 parts by mass of amino-modified epoxy resin and 50 parts by mass of unsaturated intermediate were mixed evenly, heated to 80°C with stirring, and reacted for 2 hours to prepare unsaturated water-based epoxy resin. Subsequently, 500 parts by mass of distilled water were added and stirred at a speed of 5000 r / min to obtain sizing agent emulsions with different solid contents.

[0056] Step 2: Preparation of modified nano-silica: 60 parts by mass of nano-silica powder were dried in a vacuum drying oven for 8 hours at a drying temperature of 60°C. The dried nano-silica and 30 parts by mass of KH-570 were added to a mixed solution of 100 parts by mass of anhydrous ethanol and deionized water (the volume ratio of anhydrous ethanol to deionized water is 9:1) at a temperature of 100°C, stirred for 3 hours, and centrifuged to obtain a modified nano-silica (MSiO2) emulsion.

[0057] Step 3: Preparation of carbon fiber sizing agent: 50 parts by mass of sizing agent emulsion and 10 parts by mass of modified nano-silica were mixed evenly, stirred for 2 hours at a temperature of 60° C. to obtain a carbon fiber sizing agent.

[0058] Example 2

[0059] Step 1: Preparation of amino-terminated polyether modified epoxy resin emulsions with different double bond contents:

[0060] 50 parts by mass of amino-terminated polyether and 80 parts by mass of dodecylamine were dissolved in a mixed solution of 10 parts by mass of propylene glycol methyl ether and n-butanol (the volume ratio of propylene glycol methyl ether to n-butanol was 4:1), and the mixture was heated to 80° C. with stirring and kept warm for 45 minutes to obtain a primary amine mixed solution; 30 parts by mass of epoxy resin was dissolved in 10 parts by mass of propylene glycol methyl ether, and stirred at room temperature for 10 minutes to mix them uniformly; and then the mixture was added dropwise to the primary amine mixed solution. After the addition was complete, the temperature was slowly raised to 110° C., the stirring speed was 380 r / min, and the reaction time was 3 hours to obtain an amino-modified epoxy resin;

[0061] Add 50 parts by mass of isophorone diisocyanate to 80 parts by mass of pentaerythritol triallyl ether, stir and heat to 60°C for 2 hours to obtain an unsaturated double bond intermediate;

[0062] 100 parts by mass of amino-modified epoxy resin and 50 parts by mass of unsaturated intermediate were mixed evenly, heated to 80°C with stirring, and reacted for 2 hours to prepare unsaturated water-based epoxy resin. Subsequently, 500 parts by mass of distilled water were added and stirred at a speed of 5000 r / min to obtain sizing agent emulsions with different solid contents.

[0063] Step 2: Preparation of modified nano-silica: 60 parts by mass of nano-silica powder were dried in a vacuum drying oven for 8 hours at a drying temperature of 60°C. The dried nano-silica and 30 parts by mass of KH-560 were added to a mixed solution of 100 parts by mass of anhydrous ethanol and deionized water (the volume ratio of anhydrous ethanol to deionized water is 9:1) at a temperature of 100°C, stirred for 3 hours, and centrifuged to obtain a modified nano-silica (MSiO2) emulsion.

[0064] Step 3: Preparation of carbon fiber sizing agent: 50 parts by mass of sizing agent emulsion and 10 parts by mass of modified nano-silica were mixed evenly, stirred for 2 hours at a temperature of 60° C. to obtain a carbon fiber sizing agent.

[0065] Example 3

[0066] Step 1: Preparation of amino-terminated polyether modified epoxy resin emulsions with different double bond contents:

[0067] 50 parts by mass of amino-terminated polyether and 80 parts by mass of dodecylamine were dissolved in a mixed solution of 10 parts by mass of propylene glycol methyl ether and n-butanol (the volume ratio of propylene glycol methyl ether to n-butanol was 4:1), and the mixture was heated to 80° C. with stirring and kept warm for 45 minutes to obtain a primary amine mixed solution; 30 parts by mass of epoxy resin was dissolved in 10 parts by mass of propylene glycol methyl ether, and stirred at room temperature for 10 minutes to mix them uniformly; and then the mixture was added dropwise to the primary amine mixed solution. After the addition was complete, the temperature was slowly raised to 110° C., the stirring speed was 380 r / min, and the reaction time was 3 hours to obtain an amino-modified epoxy resin;

[0068] Add 50 parts by mass of isophorone diisocyanate to 80 parts by mass of pentaerythritol triallyl ether, stir and heat to 60°C for 2 hours to obtain an unsaturated double bond intermediate;

[0069] 100 parts by mass of amino-modified epoxy resin and 50 parts by mass of unsaturated intermediate were mixed evenly, heated to 80°C with stirring, and reacted for 2 hours to prepare unsaturated water-based epoxy resin. Subsequently, 500 parts by mass of distilled water were added and stirred at a speed of 5000 r / min to obtain sizing agent emulsions with different solid contents.

[0070] Step 2: Preparation of modified nano-silica: 60 parts by mass of nano-silica powder were dried in a vacuum drying oven for 8 hours at a drying temperature of 60°C. The dried nano-silica and 30 parts by mass of KH-550 were added to a mixed solution of 100 parts by mass of anhydrous ethanol and deionized water (the volume ratio of anhydrous ethanol to deionized water is 9:1) at a temperature of 100°C, stirred for 3 hours, and centrifuged to obtain a modified nano-silica (MSiO2) emulsion.

[0071] Step 3: Preparation of carbon fiber sizing agent: 50 parts by mass of sizing agent emulsion and 10 parts by mass of modified nano-silica were mixed evenly, stirred for 2 hours at a temperature of 60° C. to obtain a carbon fiber sizing agent.

[0072] Example 4

[0073] Step 1: Preparation of amino-terminated polyether modified epoxy resin emulsions with different double bond contents:

[0074] 50 parts by mass of amino-terminated polyether and 80 parts by mass of dodecylamine were dissolved in a mixed solution of 10 parts by mass of propylene glycol methyl ether and n-butanol (the volume ratio of propylene glycol methyl ether to n-butanol was 4:1), and the mixture was heated to 80° C. with stirring and kept warm for 45 minutes to obtain a primary amine mixed solution; 30 parts by mass of epoxy resin was dissolved in 10 parts by mass of propylene glycol methyl ether, and stirred at room temperature for 10 minutes to mix them uniformly; and then the mixture was added dropwise to the primary amine mixed solution. After the addition was complete, the temperature was slowly raised to 110° C., the stirring speed was 380 r / min, and the reaction time was 3 hours to obtain an amino-modified epoxy resin;

[0075] 50 parts by mass of toluene diisocyanate was added to 80 parts by mass of pentaerythritol triallyl ether, and the mixture was stirred and heated to 60°C for 2 hours to obtain an unsaturated double bond intermediate;

[0076] 100 parts by mass of amino-modified epoxy resin and 50 parts by mass of unsaturated intermediate were mixed evenly, heated to 80°C with stirring, and reacted for 2 hours to prepare unsaturated water-based epoxy resin. Subsequently, 500 parts by mass of distilled water were added and stirred at a speed of 5000 r / min to obtain sizing agent emulsions with different solid contents.

[0077] Step 2: Preparation of modified nano-silica: 60 parts by mass of nano-silica powder were dried in a vacuum drying oven for 8 hours at a drying temperature of 60°C. The dried nano-silica and 30 parts by mass of KH-570 were added to a mixed solution of 100 parts by mass of anhydrous ethanol and deionized water (the volume ratio of anhydrous ethanol to deionized water is 9:1) at a temperature of 100°C, stirred for 3 hours, and centrifuged to obtain a modified nano-silica (MSiO2) emulsion.

[0078] Step 3: Preparation of carbon fiber sizing agent: 50 parts by mass of sizing agent emulsion and 10 parts by mass of modified nano-silica were mixed evenly, stirred for 2 hours at a temperature of 60° C. to obtain a carbon fiber sizing agent.

[0079] Example 5

[0080] Step 1: Preparation of amino-terminated polyether modified epoxy resin emulsions with different double bond contents:

[0081] 50 parts by mass of amino-terminated polyether and 80 parts by mass of dodecylamine were dissolved in a mixed solution of 10 parts by mass of propylene glycol methyl ether and n-butanol (the volume ratio of propylene glycol methyl ether to n-butanol was 4:1), and the mixture was heated to 80° C. with stirring and kept warm for 45 minutes to obtain a primary amine mixed solution; 30 parts by mass of epoxy resin was dissolved in 10 parts by mass of propylene glycol methyl ether, and stirred at room temperature for 10 minutes to mix them uniformly; and then the mixture was added dropwise to the primary amine mixed solution. After the addition was complete, the temperature was slowly raised to 110° C., the stirring speed was 380 r / min, and the reaction time was 3 hours to obtain an amino-modified epoxy resin;

[0082] 50 parts by mass of dicyclohexylmethane diisocyanate was added to 80 parts by mass of pentaerythritol triallyl ether, and the mixture was stirred and heated to 60°C for 2 hours to obtain an unsaturated double bond intermediate;

[0083] 100 parts by mass of amino-modified epoxy resin and 50 parts by mass of unsaturated intermediate were mixed evenly, heated to 80°C with stirring, and reacted for 2 hours to prepare unsaturated water-based epoxy resin. Subsequently, 500 parts by mass of distilled water were added and stirred at a speed of 5000 r / min to obtain sizing agent emulsions with different solid contents.

[0084] Step 2: Preparation of modified nano-silica: 60 parts by mass of nano-silica powder were dried in a vacuum drying oven for 8 hours at a drying temperature of 60°C. The dried nano-silica and 30 parts by mass of KH-570 were added to a mixed solution of 100 parts by mass of anhydrous ethanol and deionized water (the volume ratio of anhydrous ethanol to deionized water is 9:1) at a temperature of 100°C, stirred for 3 hours, and centrifuged to obtain a modified nano-silica (MSiO2) emulsion.

[0085] Step 3: Preparation of carbon fiber sizing agent: 50 parts by mass of sizing agent emulsion and 10 parts by mass of modified nano-silica were mixed evenly, stirred for 2 hours at a temperature of 60° C. to obtain a carbon fiber sizing agent.

[0086] Example 6

[0087] Step 1: Preparation of amino-terminated polyether modified epoxy resin emulsions with different double bond contents:

[0088] 50 parts by mass of amino-terminated polyether and 80 parts by mass of tetradecylamine were dissolved in a mixed solution of 10 parts by mass of propylene glycol methyl ether and n-butanol (the volume ratio of propylene glycol methyl ether to n-butanol was 4:1), and the mixture was heated to 80° C. with stirring and kept warm for 45 minutes to obtain a primary amine mixed solution; 30 parts by mass of epoxy resin was dissolved in 10 parts by mass of propylene glycol methyl ether, and stirred at room temperature for 10 minutes to mix them uniformly; and then the mixture was added dropwise to the primary amine mixed solution. After the addition was complete, the temperature was slowly raised to 110° C., the stirring speed was 380 r / min, and the reaction time was 3 hours to obtain an amino-modified epoxy resin;

[0089] 50 parts by mass of dicyclohexylmethane diisocyanate was added to 80 parts by mass of pentaerythritol triallyl ether, and the mixture was stirred and heated to 60°C for 2 hours to obtain an unsaturated double bond intermediate;

[0090] 100 parts by mass of amino-modified epoxy resin and 50 parts by mass of unsaturated intermediate were mixed evenly, heated to 80°C with stirring, and reacted for 2 hours to prepare unsaturated water-based epoxy resin. Subsequently, 500 parts by mass of distilled water were added and stirred at a speed of 5000 r / min to obtain sizing agent emulsions with different solid contents.

[0091] Step 2: Preparation of modified nano-silica: 60 parts by mass of nano-silica powder were dried in a vacuum drying oven for 8 hours at a drying temperature of 60°C. The dried nano-silica and 30 parts by mass of KH-570 were added to a mixed solution of 100 parts by mass of anhydrous ethanol and deionized water (the volume ratio of anhydrous ethanol to deionized water is 9:1) at a temperature of 100°C, stirred for 3 hours, and centrifuged to obtain a modified nano-silica (MSiO2) emulsion.

[0092] Step 3: Preparation of carbon fiber sizing agent: 50 parts by mass of sizing agent emulsion and 10 parts by mass of modified nano-silica were mixed evenly, stirred for 2 hours at a temperature of 60° C. to obtain a carbon fiber sizing agent.

[0093] Example 7

[0094] Step 1: Preparation of amino-terminated polyether modified epoxy resin emulsions with different double bond contents:

[0095] 50 parts by mass of amino-terminated polyether and 80 parts by mass of hexadecylamine were dissolved in a mixed solution of 10 parts by mass of propylene glycol methyl ether and n-butanol (the volume ratio of propylene glycol methyl ether to n-butanol was 4:1), and the mixture was heated to 80° C. with stirring and kept warm for 45 minutes to obtain a primary amine mixed solution; 30 parts by mass of epoxy resin was dissolved in 10 parts by mass of propylene glycol methyl ether, and stirred at room temperature for 10 minutes to mix them uniformly; and then the mixture was added dropwise to the primary amine mixed solution. After the addition was complete, the temperature was slowly raised to 110° C., the stirring speed was 380 r / min, and the reaction time was 3 hours to obtain an amino-modified epoxy resin;

[0096] 50 parts by mass of dicyclohexylmethane diisocyanate was added to 80 parts by mass of pentaerythritol triallyl ether, and the mixture was stirred and heated to 60°C for 2 hours to obtain an unsaturated double bond intermediate;

[0097] 100 parts by mass of amino-modified epoxy resin and 50 parts by mass of unsaturated intermediate were mixed evenly, heated to 80°C with stirring, and reacted for 2 hours to prepare unsaturated water-based epoxy resin. Subsequently, 500 parts by mass of distilled water were added and stirred at a speed of 5000 r / min to obtain sizing agent emulsions with different solid contents.

[0098] Step 2: Preparation of modified nano-silica: 60 parts by mass of nano-silica powder were dried in a vacuum drying oven for 8 hours at a drying temperature of 60°C. The dried nano-silica and 30 parts by mass of KH-570 were added to a mixed solution of 100 parts by mass of anhydrous ethanol and deionized water (the volume ratio of anhydrous ethanol to deionized water is 9:1) at a temperature of 100°C, stirred for 3 hours, and centrifuged to obtain a modified nano-silica (MSiO2) emulsion.

[0099] Step 3: Preparation of carbon fiber sizing agent: 50 parts by mass of sizing agent emulsion and 10 parts by mass of modified nano-silica were mixed evenly, stirred for 2 hours at a temperature of 60° C. to obtain a carbon fiber sizing agent.

[0100] Example 8

[0101] Step 1: Preparation of amino-terminated polyether modified epoxy resin emulsions with different double bond contents:

[0102] 50 parts by mass of amino-terminated polyether and 80 parts by mass of octadecylamine were dissolved in a mixed solution of 10 parts by mass of propylene glycol methyl ether and n-butanol (the volume ratio of propylene glycol methyl ether to n-butanol was 4:1), and the mixture was heated to 80° C. with stirring and kept warm for 45 minutes to obtain a primary amine mixed solution; 30 parts by mass of epoxy resin was dissolved in 10 parts by mass of propylene glycol methyl ether, and stirred at room temperature for 10 minutes to mix them uniformly; and then the mixture was added dropwise to the primary amine mixed solution. After the addition was complete, the temperature was slowly raised to 110° C., the stirring speed was 380 r / min, and the reaction time was 3 hours to obtain an amino-modified epoxy resin;

[0103] 50 parts by mass of dicyclohexylmethane diisocyanate was added to 80 parts by mass of pentaerythritol triallyl ether, and the mixture was stirred and heated to 60°C for 2 hours to obtain an unsaturated double bond intermediate;

[0104] 100 parts by mass of amino-modified epoxy resin and 50 parts by mass of unsaturated intermediate were mixed evenly, heated to 80°C with stirring, and reacted for 2 hours to prepare unsaturated water-based epoxy resin. Subsequently, 500 parts by mass of distilled water were added and stirred at a speed of 5000 r / min to obtain sizing agent emulsions with different solid contents.

[0105] Step 2: Preparation of modified nano-silica: 60 parts by mass of nano-silica powder were dried in a vacuum drying oven for 8 hours at a drying temperature of 60°C. The dried nano-silica and 30 parts by mass of KH-570 were added to a mixed solution of 100 parts by mass of anhydrous ethanol and deionized water (the volume ratio of anhydrous ethanol to deionized water is 9:1) at a temperature of 100°C, stirred for 3 hours, and centrifuged to obtain a modified nano-silica (MSiO2) emulsion.

[0106] Step 3: Preparation of carbon fiber sizing agent: 50 parts by mass of sizing agent emulsion and 10 parts by mass of modified nano-silica were mixed evenly, stirred for 2 hours at a temperature of 60° C. to obtain a carbon fiber sizing agent.

[0107] Example 9

[0108] Step 1: Preparation of amino-terminated polyether modified epoxy resin emulsions with different double bond contents:

[0109] 50 parts by mass of amino-terminated polyether and 80 parts by mass of dodecylamine were dissolved in 10 parts by mass of a mixed solution of propylene glycol methyl ether and n-butanol (the volume ratio of propylene glycol methyl ether to n-butanol was ***), and the mixture was heated to 80° C. with stirring and kept warm for 45 minutes to obtain a primary amine mixed solution; 30 parts by mass of epoxy resin was dissolved in 10 parts by mass of propylene glycol methyl ether, and stirred at room temperature for 10 minutes to mix uniformly; and then the mixture was added dropwise to the primary amine mixed solution. After the addition was completed, the temperature was slowly raised to 110° C., the stirring speed was 380 r / min, and the reaction time was 3 hours to obtain an amino-modified epoxy resin;

[0110] 50 parts by mass of dicyclohexylmethane diisocyanate was added to 80 parts by mass of pentaerythritol triallyl ether, and the mixture was stirred and heated to 60°C for 2 hours to obtain an unsaturated double bond intermediate;

[0111] 100 parts by mass of amino-modified epoxy resin and 50 parts by mass of unsaturated intermediate were mixed evenly, heated to 80°C with stirring, and reacted for 2 hours to prepare unsaturated water-based epoxy resin. Subsequently, 500 parts by mass of distilled water were added and stirred at a speed of 5000 r / min to obtain sizing agent emulsions with different solid contents.

[0112] Step 2: Preparation of modified nano-silica: 60 parts by mass of nano-silica powder were dried in a vacuum drying oven for 8 hours at a drying temperature of 60°C. The dried nano-silica and 30 parts by mass of KH-570 were added to a mixed solution of 100 parts by mass of anhydrous ethanol and deionized water (the volume ratio of anhydrous ethanol to deionized water is 9:1) at a temperature of 100°C, stirred for 3 hours, and centrifuged to obtain a modified nano-silica (MSiO2) emulsion.

[0113] Step 3: Preparation of carbon fiber sizing agent: 50 parts by mass of sizing agent emulsion and 20 parts by mass of modified nano-silica were mixed evenly, stirred for 2 hours at a temperature of 60° C. to obtain a carbon fiber sizing agent.

[0114] Example 10

[0115] Step 1: Preparation of amino-terminated polyether modified epoxy resin emulsions with different double bond contents:

[0116] 50 parts by mass of amino-terminated polyether and 80 parts by mass of dodecylamine were dissolved in a mixed solution of 10 parts by mass of propylene glycol methyl ether and n-butanol (the volume ratio of propylene glycol methyl ether to n-butanol was 4:1), and the mixture was heated to 80° C. with stirring and kept warm for 45 minutes to obtain a primary amine mixed solution; 30 parts by mass of epoxy resin was dissolved in 10 parts by mass of propylene glycol methyl ether, and stirred at room temperature for 10 minutes to mix them uniformly; and then the mixture was added dropwise to the primary amine mixed solution. After the addition was complete, the temperature was slowly raised to 110° C., the stirring speed was 380 r / min, and the reaction time was 3 hours to obtain an amino-modified epoxy resin;

[0117] 50 parts by mass of dicyclohexylmethane diisocyanate was added to 80 parts by mass of pentaerythritol triallyl ether, and the mixture was stirred and heated to 60°C for 2 hours to obtain an unsaturated double bond intermediate;

[0118] 100 parts by mass of amino-modified epoxy resin and 50 parts by mass of unsaturated intermediate were mixed evenly, heated to 80°C with stirring, and reacted for 2 hours to prepare unsaturated water-based epoxy resin. Subsequently, 500 parts by mass of distilled water were added and stirred at a speed of 5000 r / min to obtain sizing agent emulsions with different solid contents.

[0119] Step 2: Preparation of modified nano-silica: 60 parts by mass of nano-silica powder were dried in a vacuum drying oven for 8 hours at a drying temperature of 60°C. The dried nano-silica and 30 parts by mass of KH-570 were added to a mixed solution of 100 parts by mass of anhydrous ethanol and deionized water (the volume ratio of anhydrous ethanol to deionized water is 9:1) at a temperature of 100°C, stirred for 3 hours, and centrifuged to obtain a modified nano-silica (MSiO2) emulsion.

[0120] Step 3: Preparation of carbon fiber sizing agent: 50 parts by mass of sizing agent emulsion and 30 parts by mass of modified nano-silica were mixed evenly, stirred for 2 hours at a temperature of 60° C. to obtain a carbon fiber sizing agent.

[0121] Performance testing:

[0122] The properties of the sizing agents obtained in Examples 1 to 10 were tested, and the test results are shown in Tables 1 and 2.

[0123] Table 1 Performance test results

[0124]

[0125] Table 2 Performance test results

[0126] Sample number Emulsion particle size / nm Static stability / ≥days Dilution stability Example 1 80～90 120 qualified Example 2 80～100 120 qualified Example 3 60～80 120 qualified Example 4 70～80 85 qualified Example 5 90～150 90 Unqualified Example 6 80～100 72 Unqualified Example 7 70～120 100 qualified Example 8 80～120 100 qualified Example 9 80～90 88 qualified Example 10 100～110 90 Unqualified

[0127] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0128] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A corrosion-resistant epoxy resin composite carbon fiber sizing agent, characterized in that: The corrosion-resistant epoxy resin composite carbon fiber sizing agent is prepared by blending amino-terminated polyether modified epoxy resin emulsion with different double bond contents and modified nano-silicon dioxide; The mass ratio of the amino-terminated polyether modified epoxy resin emulsion with different double bond contents to the modified nano-silica is 5-10:5-10; The amino-terminated polyether-modified epoxy resin emulsion with different double bond contents comprises, by weight, 30 to 60 parts of epoxy resin, 50 to 100 parts of amino-terminated polyether, 80 to 200 parts of aliphatic primary amine, 50 to 100 parts of isocyanate, 80 to 100 parts of enol ether, 10 to 30 parts of cosolvent, 10 to 20 parts of reaction solvent and 300 to 500 parts of water.

2. The corrosion-resistant epoxy resin composite carbon fiber sizing agent according to claim 1, characterized in that: The particle size of the modified nano-silica is 20 to 50 nm; The preparation steps of the modified nano-silica include: mixing nano-silica, a silane coupling agent and a mixed solvent and reacting the mixture to obtain the modified nano-silica.

3. The corrosion-resistant epoxy resin composite carbon fiber sizing agent according to claim 2, characterized in that: The mass ratio of the nano-silica, silane coupling agent and mixed solvent is 6-10:3-4:10-15; the silane coupling agent includes one or more of KH550, KH570 and KH-560; the mixed solvent is water and ethanol; the reaction temperature is 80-100° C., and the reaction time is 2-3 hours.

4. The corrosion-resistant epoxy resin composite carbon fiber sizing agent according to claim 1, characterized in that: The preparation steps of the amino-terminated polyether modified epoxy resin emulsion with different double bond contents include: According to the prescribed amount, the amino-terminated polyether, the aliphatic primary amine and the cosolvent are heated and mixed to obtain a primary amine mixed solution; the epoxy resin is first dissolved in the reaction solvent to obtain a mixed solution, and the mixed solution is then dropwise added to the primary amine mixed solution and reacted to obtain an amino-modified epoxy resin; Mixing isocyanate and enol ether in the prescribed amounts and subjecting them to a first heating reaction to obtain an unsaturated double bond intermediate; According to the prescribed amount, the amino-modified epoxy resin and the unsaturated double bond intermediate are mixed and subjected to a second heating reaction to obtain a water-based epoxy resin, and water is added thereto to obtain the amino-terminated polyether-modified epoxy resin emulsion with different double bond contents.

5. The corrosion-resistant epoxy resin composite carbon fiber sizing agent according to claim 4, characterized in that: The aliphatic primary amine includes one or more of dodecylamine, tetradecylamine, hexadecylamine and octadecylamine; the cosolvent is a mixture of alcohol ether and n-butanol; the alcohol ether includes propylene glycol methyl ether or ethylene glycol methyl ether; the heating and mixing temperature is 80-95° C. and the time is 45-60 minutes.

6. The corrosion-resistant epoxy resin composite carbon fiber sizing agent according to claim 4, characterized in that: The epoxy resin includes one or more of a solid epoxy resin, a low-viscosity epoxy resin E51, and a hydrogenated epoxy resin; the reaction solvent includes one or more of propylene glycol methyl ether, ethylene glycol methyl ether, and tetrahydrofuran; the reaction temperature is 110-120° C., the stirring speed is 300-500 r / min, and the reaction time is 2-4 hours.

7. The corrosion-resistant epoxy resin composite carbon fiber sizing agent according to claim 4, characterized in that: The isocyanate comprises one or more of toluene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate and diphenylmethane diisocyanate; the temperature of the first heating reaction is 60-70° C., and the time is 2-3 hours.

8. The corrosion-resistant epoxy resin composite carbon fiber sizing agent according to claim 4, characterized in that: The temperature of the second heating reaction is 70-90° C., and the time is 2-3 hours; the solid content of the amino-terminated polyether modified epoxy resin emulsion with different double bond contents is 30-50%.

9. The method for preparing the corrosion-resistant epoxy resin composite carbon fiber sizing agent according to any one of claims 1 to 8, characterized in that: The steps include: The amino-terminated polyether modified epoxy resin emulsion with different double bond contents and modified nano-silicon dioxide are mixed and reacted to obtain the corrosion-resistant epoxy resin composite carbon fiber sizing agent.

10. The preparation method according to claim 9, characterized in that The reaction temperature is 50-60° C. and the reaction time is 2-3 hours.

Images